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Thread: Talking Technical on Tech Cameras

  1. #51
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    Re: Talking Technical on Tech Cameras

    Distance Measurement with Laser RangeFinder


    I have two Laser Rangefinders to measure the object distances; Leica Disto 5 and Leupold RX1000. Each has its own strengths for a landscape photographer like me who focuses a tech camera based on the distance measurement.

    Leica Disto 5:

    It uses both a 'red' laser point and 'digital pointfinder' which is a built-in video camera with up to 4x zoom. The 'red dot' laser pointer is difficult to see and is almost useless in outdoor application. The 'digital pointfinder' is easy to use, as long as it is on a tripod, and very accurate. A simple distance measurement can be done in 'digital pointfinder' mode in two-steps; aim an object with crosshair in LED viewfinder then press Red 'Distance' button. To measure x and y distance of an object for Tilt/Swing, you have to first locate the object with LED viewfinder then use proper 'function key' sequences.

    The specification claims the distance range up to 100 meters but I haven't been successful to measure farther than 40 - 45 meters in actual field application. I did measure an object (aluminum Street sign) that is 65 meters away but the range is more limited with 'natural objects' such as tree trunks or rocks. It claims 1.5 mm accuracy up to the distance of 30 meters (I haven't verified it ).

    Leupold RX1000:

    It is very small, a monocular with 6x optical viewfinder and use 'pulse of infra red' to measure the distance. It is designed for handheld use and does not have a tripod mounting screw hole.
    I needed a rangefinder which can measure the distance between 50 and 100 meters accurately (of tree trunks and rocks) and Leupold does very well. Leupold has a model with a built-in Inclinometer (to measure the angle from the horizon) but I chose the one without it.

    I made several measurement soon after I got it while walking a nearby nature/bike trail. The trail has 'half mile' markers (805 meters) and is winding, so I had to make 5 - 8 measurement of varying distances while covering a 'half-mile' increments. I picked non-reflecting objects; tree, power poles, bench, rocks, etc., from 40 meters to 350 meters distance, and added up for each 'half-mile' marker to see the combined accuracy. I was handholding it and made two readings for each object and keep the average. The overall accuracy of my measurement was approximately 5% higher, never lower. I concluded that it was an operator's error, not able to hold it steady and got the reading for the tree behind.

    The specification claims the distance range up to 640 meters of non-reflecting surface (such as tree) with 2.5% accuracy the distance beyond 110 meters. The minimum distance is 5 meters.

    Jae Moon
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    Re: Talking Technical on Tech Cameras

    Check this out (repost form Arca Rm3di) :

    https://itunes.apple.com/us/app/tilt...529611767?mt=8
    Arca Swiss Rm3di | XF | P1 IQ380 |

    http://www.awolfphotography.com/

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    Re: Talking Technical on Tech Cameras

    Anyone that has a tip for a small compact optical rangefinder (not laser)? It does not need to be that accurate, I'd just like to have something that could help me figure out if the distance is about 30, 50, 80 or 130 meters...

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    Re: Talking Technical on Tech Cameras

    Leitz and Fotoman both made small optical rangefinders. I used to have both, but sold my Fotoman to some guy in Carmel.

    You could check eBay.

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by awolf View Post
    Check this out (repost form Arca Rm3di) :

    https://itunes.apple.com/us/app/tilt...529611767?mt=8


    Let us know how it works and how you like it.

    Jae Moon

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    Re: Talking Technical on Tech Cameras

    I was hoping some of you "pros" can tell me
    Arca Swiss Rm3di | XF | P1 IQ380 |

    http://www.awolfphotography.com/

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by stephengilbert View Post
    Leitz and Fotoman both made small optical rangefinders. I used to have both, but sold my Fotoman to some guy in Carmel.

    You could check eBay.
    Thanks for the tips. The Leitz fokos rangefinder looks really cute, quite expensive though. I have an all-mechanical camera, mechanical watch for longer exposures, so of course I want a retro-looking mechanical rangefinder to use with my DoF tables . Unfortunately the prices on it seems quite high...

    Tried the Disto D5 and it's nice, but it's a heavy thing with batteries with overkill precision. As a ground glass user the D5 precision is not necessary. The rangefinder would be used to find out which aperture to use for sufficient DoF, or if it's useful to tilt, but setting the focus is done by looking at the ground glass with loupe.

    I do nowadays carry a small key-ring laser pointer though, which can be used in very poor light conditions to get a spot to focus at.

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by torger View Post
    Tried the Disto D5 and it's nice, but it's a heavy thing with batteries with overkill precision. As a ground glass user the D5 precision is not necessary. The rangefinder would be used to find out which aperture to use for sufficient DoF, or if it's useful to tilt, but setting the focus is done by looking at the ground glass with loupe.

    Ander:

    You may look into Leupold series if you don't mind its 'non-retro mechanical', but it comes in hunter' camouflage . It is very small, half the size of cigarette pack (a bit thicker). It's shortcoming, as stated in my previous post, the minimum distance range is 5 meters or so. However, I found it much easier to use than Disto for general distance measurement. Target marker and distance measurement are visible in viewfinder such that you can locate, aim and measure the distance in one motion.

    Jae Moon
    Last edited by Jae_Moon; 3rd May 2013 at 08:49.
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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by torger View Post
    Thanks for the tips. The Leitz fokos rangefinder looks really cute, quite expensive though. I have an all-mechanical camera, mechanical watch for longer exposures, so of course I want a retro-looking mechanical rangefinder to use with my DoF tables . Unfortunately the prices on it seems quite high...
    The Ansco DeJur is is a really nice rangefinder modeled after the Leica design--this is the one I used with a Horseman SW612 and I still have. Waterman and Voightlander made good rangefinders too. Waterman has a close focus model. The Kodak rangefinders, while sophisticated, can yellow and darken with age.

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    Re: Talking Technical on Tech Cameras

    Hello everyone on this forum!
    I just registered on get dpi in order to let you know that this a great thread.
    Can't wait for this app to be available.

    I'd also like to point you to this app (maybe you already use it) called Snapi, made by Guillaume Sébire. The app works well for calculating tilt angle and focus distance to get a horizontal or slanted plane of sharpness, even with a tilted camera.
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    Re: Talking Technical on Tech Cameras

    As a very beginner in the Tech Cam world this is one of the most helpful threads I've read so far. Still heavily on the learning side for me these posts are of such incredible value in so many ways.

    Thousand Thanks Jae for starting and to all others for contributing loads of knowledge to this great discussion!!

    Arved

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    Re: Talking Technical on Tech Cameras

    i've tried the tilt-calculator app which awolf mentioned today, but can't get it right so far... :-(

    i set the sensor type, and the focal length (unfortunately there is no 43mm lens so i set it to 45mm).

    situation: my gardenfloor - grass and concrete entranceway
    43mm schneider lens - wide open / 130mm hight of the lens axis above ground / no camera tilt

    it calculates: 2° lens tilt / focal distance: infinity to set the plane of focus to the ground

    but that didn't work - the ground was sharper than without tilt, but not sharp.
    if applied 3° tilt it was tack sharp at the bottom of the image, but it seemed that the POF was pointing downwards - only the foreground was sharp...

    you can set the actual FD to get a different angle of the POF. so i tried to focus at 15m it seemed to get quite right. (the calculated near limit of the DOF is -76,9° and the far limit -93,4° / -90° = right-angled to the sensor plane without camera tilt)

    but basicly if i set the POF to the ground, it should be tack sharp.
    but it wasn't...

    but i can't figure out why.

    jae moon, could you please verify the given calculation (see screenshot) with your formulars?
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    Re: Talking Technical on Tech Cameras

    in reply to Photomgraphy's test of the Snapi app :

    I checked as well as I could the results of the Snapi app, using the Merklinger formulas and Snapi seems to be working correctly. Although I am not super at math.

    About the rm3di : The only thing I disliked about the rm3di is the tilting mechanism. The knob that sets the tilt, has some play in it. At least on my camera.
    So I checked with an iphone bubble level app (not the most precise tool) whether a setting of 3 degrees on the rm3di was tilting the lens by 3 degrees and the conclusion was that it was closer to 2,5 degrees. I tried different settings with the rm3di and my impression is that the play in the tilt-knob results in about half a degree less tilt that you want to set.
    What seems to give more accurate settings on the rm3di is to first turn the knob to maximum tilt (5 degrees) and then turn it back to the desired setting. This has worked fine for me. This may explain your results, why your test seemed to work better when dialing in more tilt than Snapi indicated.

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by Malaba View Post
    About the rm3di : The only thing I disliked about the rm3di is the tilting mechanism. The knob that sets the tilt, has some play in it. At least on my camera.
    As I also discussed in my previous post, the 'wheel' to adjust the lens tilt in Rm camera is the weakest design feature which should be improved upon immediately. However, I think the problem you have (some play in it) is a defect and you should contact your dealer for repair.

    Jae Moon

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by photomgraphy View Post
    jae moon, could you please verify the given calculation (see screenshot) with your formulars?
    I am posting this to let everyone know that I communicated with Thomas concerning his question via PM. I prefer not to comment on someone else's products without thorough evaluation in a public forum.

    Jae Moon

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by Malaba View Post
    About the rm3di : The only thing I disliked about the rm3di is the tilting mechanism. The knob that sets the tilt, has some play in it. At least on my camera.
    I agree with Jae. The knob is not my favorite part of the design, but it works well, and it should have no play at all. I'd take it to your dealer for inspection/adjustment/service.
    Doug Peterson , Digital Transitions | Email
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    Free Trial of NuvoFocus (Spreadsheet version)

    A while ago, I posted (and removed soon after) a short story concerning my experiences of developing an App called NuvoFocus, which performs several critical tasks for Tech Camera users.

    I decided not to bring the App to market after extensive beta testings and market studies. There were several reasons for my decision and the following were most critical.
    1. iOS App Store does not allow 'free trial' period.
    2. Selling and maintaing an App via iOS App Store requires a substantial investment both in money and time.
    3. Difficulty of providing technical supports.
    4. iOS App Store is not designed to sell an App which is 'professional, expensive and with small potential market.' (Today, the average price of an iOS App is16˘, while 90% are free and 6% is at 99˘)

    I have decided to give it another try, this time as a spreadsheet running on iPhone or iPad, and distribute it independently, since I strongly believe many benefits to Tech Camera users.

    The program have following functions:
    1. Calculate HFD (for given focal length, aperture and CoC settings).
    2. Calculate the DOF for a given subject distance (for given focal length, aperture and CoC settings).
    3. Calculate the focus distance for given Near and Far DoF distance.
    4. Calculate the required Lens Tilt Angle, with or without camera tilt, and required focus distance setting.
    5. Indexed Focus Setting with Lens Equation (translate focus distance into an index)

    The program is designed in three separate modules; Simple DoF (items 1, 2 and 3 above), Lens /Camera Tilt Calculator (item 4), and Indexed Focus System (item 5).

    I am starting Free Trial Tests with anyone who would sends me a PM with her/his email address and name. I will send you a Free Trial version in EXCEL format.

    The Free Trial version is a fully functioning with following limitations:
    1. The trial period is for 14 days, and the program will not function after that.
    2. It is 'encrypted and protected' so you will not see the mathematical equations.
    3. It cannot be exported to NUMBERS.
    4. Simple DoF module will function beyond the free trial period.
    5. Lens Equations for SK35XL, one for AS RM focus system and another for ALPA (or Cambo) HPF focus ring, are included for you to experience the benefits of Indexed Focusing System.
    6. Up to three user's lens data can be added for Simple DoF and Lens/Camera Tilt without Lens Equations.

    Final pricing has not been determined yet but I am planning for a two-tiers pricing for the program.
    1. Simple DoF and Lens/Camera Tilt calculator at $$
    2. One Lens Equation for Indexed Focus Setting at $$, and additional equations at $$ each.

    The final release program will be in NUMBERS format, so it can be used in either iPhone or iPad. You will need to buy a copy of NUMBERS (iOS spreadsheet program from Apple at $10).

    Notes on Lens Equation:

    Simply put, a lens equation is a mathematical formula that translate the lens calibration data into a simple computer code by means of regression analysis. For example, an AS RM mount lens is provided with a 44 points calibration data on a laminated card. An ALPA (or Cambo) HPF style lens is available with calibration data which are in 7 pages of PDF file.

    AS RM camera has built-in Index to set accurate focus while an HPF ring has tick marks and distance marking at each 5 degree rotation. A thin adhesive plastic strip, with a linear scale of 0-270 will be provided with each lens equation purchase, to be affixed on the top of HPF ring scale.

    General notes:

    It will be easy to understand the program to many of you. However, it requires a little bit of mathematical knowledge and full understanding of Disto operation. I hope to answer any technical questions in this forum during Free Trial Period. 14 days trial period starts from the date when I email you the program.



    I will follow up with a "Quick Start' intro of the program.


    Jae Moon
    Last edited by Jae_Moon; 14th August 2013 at 19:50.

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    Free Trial of NuvoFocus (Spreadsheet version)

    NuvoFocus has three sheets; PROG, DATA and CALC. CALC is protected and cannot be viewed.

    Cells that are shaded in Light Blue is for user INPUT and in Light Yellow is calculated OUTPUT.





    DATA PAGE



    You enter data only once, when you first start. Select prefered Unit of Distance, meter or feet. All measurement should be in decimal. NOT 5 feet 2 inch, BUT 5.17 feet.

    Next, enter DB and Lens information. Up to 5 lenses data maybe entered. For Free Trial Version, first two spaces are reserved for SK35XL, one for AS RM mount and another for ALPA (or Cambo) mount with HPF ring, and Lens Equations are pre-installed.

    Try to get an accurate data for lens focal length. SK35XL has nominal focal length of 36.4 mm instead of 35 mm according to their data sheet.

    Select the type of Lens Mount; AS RM or ALPA (or Cambo). I made a BIG assumption that no one would have both AS RM camera and ALPA (or Cambo) camera.

    In Trial Version, lens # 1 is AS RM mount and lens # 2 is ALPA (or Cambo) mount.





    PROGRAM PAGE



    DOF

    Select a lens to be used. The same lens is assumed for both DOF and Lens Tilt Calculation.

    Select CoC as # of pixel pitch. It can be any number, ie, 2 or 3.3 or 1.4142. The same CoC value is used for LENS/CAMERA Tilt calculation.

    All distance measurement should be done with a Disto mounted on a tripod or on camera, especially, if you want to do Lens/Camera Tilt. You have to measure two distances once Disto is mounted; the horizontal distance between Disto sensor and DB sensor and the vertical distance between the axis of camera lens and Disto Sensor. The program expects you to enter the 'horizontal distance offset' into a Disto. My setup has 50 mm distance between Disto sensor and DB sensor, so I entered 50 mm as OFFSET into my Disto, and the Disto reading automatically shows the distance between the DB sensor plane and Subject.



    One way a Disto can be mounted

    A2 in the diagram is the horizontal distance between Disto sensor and DB image sensor, D is tripod height and C is the distance between Lens Axis and Disto Axis.



    LENS/CAMERA TILT

    Enter the height of Tripod and the vertical distance between the two axis, Disto and camera lens. My set up has 119 mm distance between two axis. The camera height is calculated by adding these two numbers.

    Now make two distance measurement using a Disto, Near and Far Subject (both horizontal and vertical distance). Learn how to do it by reading Disto Manual pg 11, 'Direct Horizontal Distance'.

    Enter Camera Tilt Angle (if you are tilting the camera in addition to the lens tilt). The program use the convention that the tilt angle is POSITIVE when the camera is tilted forward (however, Disto displays forward tilt as a negative value).

    The program provide the required Lens Tilt Angle and the focus distance. It also calculate the Wedge of Dof at a specific distance.

    The program will display the message, 'Indexed Focus is not abled for this lens' if you select other the lenses without Lens Equation (Lens # 1 (with AS RM camera) or Lens # 2 (with ALPA (or Cambo) HPF mount with Trial version).


    INDEXED FOCUS SETTING

    With this option abled, all calculated and/or measured subject distance will be displayed in simple and easy to use Index Numbers.




    OUPUT with AS-RM mount Lens


    HFD, Subject Distance, Target Distance with Near/Far DoF and Lens /Camera Tilt Subject Distances are displayed in both in distance measurement unit (meter or feet) and also in AS-RM Focus Index, including the Color designations.




    OUTPUT with ALPA (or Cambo) HPF Ring Lens


    Again, HFD, Subject Distance, Target Distance with Near/Far DoF and Lens /Camera Tilt Subject Distances are displayed in both in distance measurement unit (meter or feet) and also in in degree of rotation (0 - 270).


    PM me with your name and email address if you want to try a Free Trial version of NuvoFocus. I will start send you the copy beginning next Monday, August 19.



    Jae Moon
    Last edited by Jae_Moon; 14th August 2013 at 20:00.
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    Free Trial of NuvoFocus (Spreadsheet version)

    I forgot to state clearly that the Trial version runs on computers not on iOS devices; iPhone or iPad. It may run on iOS devices if you have MS Office 365 (I don't have the service and don't know if it works or not).

    Jae Moon

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    Free Trial of NuvoFocus (Spreadsheet version)

    The Free Trial is still available. In the mean time, I would like to show a 'Sneak Peek' of the Release version on iPhone, running on NUMBERS.

    You can re-size and scroll the program.


    Screen Shot:






    PM me if you want to have a free trial copy of NuvoFocus.


    Jae Moon
    Last edited by Jae_Moon; 23rd August 2013 at 17:11.

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    Re: Talking Technical on Tech Cameras

    Jae,

    the trial version is working well so far. I have not put it fully through its paces yet, but it is looking very good. If you release an IOS version, you can put me on the list. As per previous posts, I think your pricing is in line with the functionality, just my two cents

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    Re: Talking Technical on Tech Cameras

    Jae,
    The screen shots of the iPhone 5 'trial' in your post above does not show for me.

    Cheers, -Peter
    Alpa TC • STC | IQ140 | 24XL • 35XL • 120N-ASPH
    www.peterlomdahl.com

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by PeterL View Post
    Jae,
    The screen shots of the iPhone 5 'trial' in your post above does not show for me.

    Cheers, -Peter
    Move the pics to Flickr. Hope it works better.

    Jae Moon

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    Free Trial of NuvoFocus (Spreadsheet version)

    A quick note.

    If you open the web page with iPhone 5, you can size the screenshots to see the approximation of NuvoFocus's look running on NUMBERS.

    Jae Moon

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by jagsiva View Post
    Jae,

    the trial version is working well so far. I have not put it fully through its paces yet, but it is looking very good.
    Jag:

    Make sure you try lens/camera tilt before the free trial runs out. If you have a Disto, it will be reasonably quick even without a 'fixed' Disto mount.

    Jae Moon

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by Jae_Moon View Post
    Jag:

    Make sure you try lens/camera tilt before the free trial runs out. If you have a Disto, it will be reasonably quick even without a 'fixed' Disto mount.

    Jae Moon
    Thanks Jae. I do have a Disto, and will put it to test.

    Thanks again for all the hard work on this.

    Jag

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    Free Trial of NuvoFocus (Spreadsheet version)

    Many have asked about the Disto mounting method and the reason for a fixed mounting platform.

    It is critically important to have accurate positional relationship between camera and near/far object locations if you want to calculate the lens tilt and the required focus distance.

    By industry convention, the center point of camera is the center of DB sensor plane instead of the nodal point of lens. Therefore, one should measure the distances (horizontal and vertical) between the center point of DB sensor and both Near and Far object using a Disto. Having a 'Fixed Mounting Platform' for both Camera and Disto makes this process much easier.



    My 'Fixed Mounting Platform'

    A/S Cube or similar device is the perfect tripod head for Lens Tilt application since it gives very accurate 'pitch' control. I am using a clone, PhotoClam.

    I have RRS MPR-CL II as a base plate to mount both camera and Disto. RRS Mini Clamp Package is used for mounting Camera on MPR-CL II, and Disto is attached to Oben QR-10 and lock onto the integral clamp of MPR-CL II.





    Making Measurement


    Two 'offset' measurement are needed to make repeated Disto readings easier. Horizontal offset is the distance between Disto sensor and DB image sensor planes, and Vertical offset is the distance between axes of Disto sensor and camera lens.

    You are recommended to enter the 'horizontal offset' into Disto setup so the reading will automatically compensate the offset.

    Vertical offset should be entered into NuvoFocus data sheet (only once).

    You are also required to measure the Disto height from the ground, so the sum of Disto height and vertical offset gives us the camera height.





    Jae Moon

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    Re: Talking Technical on Tech Cameras

    Hello Jae,

    The software appears to work great -- though I did have to go read my Disto manual for the tilt measurements

    Many thanks for the effort and thought that you've put into this, and for all of your useful and informative posts.

    Best, John.

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    Re: Talking Technical on Tech Cameras

    Hello Jae,

    To elaborate a bit more on my previous post -- my context to evaluating Nuvofocus is that almost all my work with my Rm3d is architectural, especially interiors. So my primary interest is in the indexed focus -- this is great! -- just what I've wanted to stop me having to do interpolations in my head every time I measure the distance to focus a shot.

    I've very rarely used tilt (probably less than 10 times) -- hence the reason why I had to go find the Disto manual! So I just tried a simple set-up here at home hand-holding the Disto to see whether I could understand the process and mechanics using your (excellent) instructions & software and get what seemed sensible results -- I'm pleased to say that I could follow it all and it seems to work, so maybe I will get to use tilt a bit more in the future!

    Best, John.

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    Re: Talking Technical on Tech Cameras

    Jae, with the Disto setup, I assume you'll need to adjust an offset number if you're using a rot amount/rotaslide and removing the spacer ring on the lens. Doing this has a net effect of moving the entire system back about .5", so subject distance would increase by .5". Am I correct in this thinking?

    Cheers...

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by jagsiva View Post
    Jae, with the Disto setup, I assume you'll need to adjust an offset number if you're using a rot amount/rotaslide and removing the spacer ring on the lens. Doing this has a net effect of moving the entire system back about .5", so subject distance would increase by .5". Am I correct in this thinking?

    Cheers...
    Jag:

    It is correct.

    The reference point (indirectly, since the Hinge Point is the real reference point which is directly below, parallel to sensor plane, on the ground) is the center of DB image sensor, and all object locations should be measured from it. Add the additional offset whenever you use rotaslide.

    Again, it has been lot easier for me since I established a 'fixed mounting platform'. With my setup, the horizontal offset is 50 mm and the vertical offset is 119 mm. I entered 50 mm into my Disto and 119 mm into my copy of NuvoFocus. However, I have to remember to subtract 50 mm when I measure the Disto height.

    Jae Moon
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    Re: Talking Technical on Tech Cameras

    Jae,

    Thanks for the Nuvofocus trial spreadsheet. I was able to spend the morning testing this with very good results.

    I suspect that my measurements were not 100% accurate and I am going to need to find a way of mounting my Disto on a tripod. Handholding it in approximately the right position is probably not good enough. My other concern is how to look 'down' onto the Disto screen. If I have the tripod set to hold the camera at my eye level it's then very difficult to look at the Disto screen. I could take a stepladder or a plastic crate I suppose but there must be a better way.

    The other thing I do not understand is the Wedge of DOF at distance, Xr meter. I understand the wedge of DOF but cannot interpret the numbers represented by 'Xr', 'Bottom', at 'PSF' and 'Top'. I'm still learning.

    Overall I am impressed and would seriously consider buy Nuvofocus at a reasonable price.

    Incidentally, this whole question has scrambled my brain more than a few times since buying my Factum. Your posts have been very helpful indeed. I also found that Harold Merklinger's book "Focusing the View Camera" is available from Merklinger's Photo Books Chapter 2 gives a very concise and clear explanation which others delving here may find as useful as I did.

    Keep up the good work. A simple iPhone/iPad app will be very useful. Now to find some light-weight folding steps for the Disto.

    Miles.
    Last edited by MILESF; 27th August 2013 at 10:00. Reason: Sign-off name

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by MILESF View Post
    I was able to spend the morning testing this with very good results.
    I am glad that you figured the program out in short period of time and got very good result.


    If I have the tripod set to hold the camera at my eye level it's then very difficult to look at the Disto screen. I could take a stepladder or a plastic crate I suppose but there must be a better way.
    Let me know if anyone comes up with the idea. I think it would have a better potential for financial success.


    The other thing I do not understand is the Wedge of DOF at distance, Xr meter. I understand the wedge of DOF but cannot interpret the numbers represented by 'Xr', 'Bottom', at 'PSF' and 'Top'. I'm still learning.
    I will post a 'Manual' soon, which will show lot more details in how to use the program.


    Overall I am impressed and would seriously consider buy Nuvofocus at a reasonable price.
    The version that runs on iOS devices are ready and I am finalizing the prices for modules.


    Jae Moon

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    A Manual for NuvoFocus (Final release version)

    NuvoFocus


    This software is NOT an iOS app but a 'spreadsheet' that runs on iOS devices with NUMBERS. NUMBERS is an app by Apple and can be purchased at $10 from AppStore.

    There are two sheets; PROG and DATA, for data input and output. Light Blue shaded cells are for user data input and Yellow shaded cells display the result.




    DATA sheet is for entering your lens inventory, DB info, unit of measurement, type of lens mount, the vertical offset of Disto from lens axis. You are required to enter these data only once. In addition, you will enter your lens selection and COC for the shoot.

    PROG sheet includes Simple DOF, Lens Tilt, and Indexed Focus.



    Simple DoF:

    1. Calculate HFD at user defined lens aperture.
    2. Calculate Near and Far DoF at user defined subject distance.
    3. Calculate the required subject distance with user defined Near and Far DoF.


    Lens Tilt:

    1. Calculate required Lens Tilt Angle and Focus Distance with two user defined location (Near and Far) with or without additional camera tilt. Also, required is Disto Height.
    2. Calculate the shape of DoF Wedge. It calculate the location of Near (Top Wedge) DoF and Far (Bottom Wedge) DoF at any user defined distance from camera. Data to be entered are Disto readings (horizontal and vertical distance )of two locations (near and far).


    Wedge of DoF:

    1. PSF (Plane of Sharp Focus) is the plane on which the tilted lens is focused ON and everything on it are in sharp focus, and it intersects with both Near and Far Subject locations.
    2. The shape of Top and Bottom Wedge allows the user to verify if a subject from a certain distance from camera is within the boundary of acceptable DoF.
    3. Both Top and Bottom Wedge are defined in X-Y coordinates, where the point on ground (on which tripod sits) directly below the DB image sensor is zero point (X=0, Y=0).
    4. For example (see 1), the boundary of acceptable DoF at a 10 meters distance from camera is between 0.5 meter below and 3.04 meter above the ground. PSF is at 1.28 meter above the ground.
    5. Refer to the diagram shown in post # 3 of this thread for detailed explanation of above mentioned geometry.


    Indexed Focusing:

    1. It translates both measured and calculated distances into easy to used Indexed Focusing.
    2. AS-Rm series already have Indexed Focusing concept, however, NuvoFocus takes extra steps to make the workflow much simpler.
    - Eliminate the needs for looking up 'laminated cheat sheet.'
    - You can create your own specific Lens Equation instead of generic calibration provided by manufacturer. All SK35XLs do not have the same optical characteristics.
    3. HPF ring requires 'mental interpolation' since it only has distance markings for every 5 degree of rotation.
    4. It gives the Index in Degree, and can be used with a thin self adhesive plastic strip (provided with Lens Equation) affixed over the distance scale of HPF.
    5. It gives precise focus setting ability to take maximum advantage of very high quality cameras, lenses and DBs.
    6. Lenses with Lens Equation are marked 'Y' in column titled LE (see 2).


    Jae Moon
    Last edited by Jae_Moon; 28th August 2013 at 07:28.

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    A Manual for NuvoFocus (Final release version)

    NuvoFocus


    Input Method:





    1. Most data are entered by 'double tapping' on the cell. A key pad will be displayed and you tap 'Green Check Mark' to complete. You may enter both TEXT and NUMERIC data, by tapping on 'T' or '42' at the top of screen, respectively (see Pic # 1).

    2. Selection of measurement unit is done by tapping on the cell, then the choice of METRIC or IMPERIAL will be displayed. Select and touch 'Done'. (see Pic # 2)

    3. Selection of Lens Mount is done by tapping on the cell, then choice of AS RM or HPF (ALP or CAM) will displayed. Select and touch 'Done'. (see Pic # 3)

    4. Selection of CoC is done by tapping on the cell, then UP or DOWN button will be displayed at the bottom of screen. Tap button until desired value is displayed, then touch 'Done'. You may select from 0 to 10 in 0.5 increment. (see Pic # 4)

    5. You can select a lens by tapping on the cell, then the selection (1 - 5) will be displayed. Make selection then touch 'Done". (see Pic # 5)

    6. Lens aperture are entered by 'tapping' on the cell, then f-stop from 4.5 to 32 in 1/3 stop are displayed . Tap on desired setting then touch 'Done'. (See Pic # 6)


    A couple notes using NUMBERS with iOS devices.

    1. iCloud will back up the file as soon as you close a particular file if any changes are made to it, including any changes to data.
    2. It is recommended to open NuvoFocus as a copy, not original, just in case.
    3. Size the screen to fit the tables to your liking.


    Jae Moon

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    A Manual for NuvoFocus (Final release version)

    NuvoFocus



    Two big attractions of a Tech Camera are; the availability of the best optical quality lenses; and capability of 'movements' - shift, tilt, swing.

    Two big challenges of a Tech Camera to a photographer are; difficulty to focus accurately; and less than ideal means of composing the images.



    NuvoFocus was designed to solve the first challenge; means of accurate focusing with or without lens TILT, SWING, or CAMERA TILT.


    A quick comment on built-in screen of DBs:

    It is my humble opinion that no matter how great a built-in display of DBs becomes, with or without LiveView, it will not meet the expectations of most photographers with Tech Cameras. Display screen is TOO SMALL since we are accustomed to staring at 30" high resolution screens, with 100% view at a click of mouse. We cannot go back composing and focusing on 3.2" screen when an iPad gives us 9.7" screen and an old 4x5 View Camera gave us 6 +" ground glass.

    I do not have any better solution. For now, I am content with lugging 13" Retina MacBook Pro and tethering to DB for fine adjustment of my composition, and relying 100% on NuvoFocus for accurate focusing.


    A Simple Argument for Precise Focusing:

    It may seems silly to some that a photographer should use 'mathematical' formulae to get a focus setting while creating 'art with soul'. My only argument would be, 'IT IS A TOOL' just like paint brushes or color pigments for artists.
    It is a step which allows a photographer to make her workflow simpler and to take advantages of her lenses and DB for better results.


    Distance Measurement:

    A Disto is preferred device, especially, if Lens Tilt is to be used. It can be handheld for Simple DOF but should be mounted on a tripod if Lens Tilt is used.

    The specification claims that Disto can measure distance range up to 100 meters but I haven't been successful any farther than 40 - 45 meters in actual field application. I did measure an object (aluminum Street sign) that was 65 meters away but the range is more limited with 'natural objects' such as tree trunks or rocks.

    HFD (Hyper Focal Distance) with CoC of 20.4 microns and f = 8 is 50 meters for SK90, 61 meters for SK100, and 88 meters for SK120. Which means, a Disto may not cover the needed distance measuring ranges for lenses longer than 100 mm or so.

    In Lens Tilt application, it is not necessary to select 'FAR' object at greater distance since we are using 'Wedge of DoF'. The boundary of acceptable DoF extends to 'Infinity' within defined angles.

    For example shown in post # 84, the vertical range between 3.04 meter above and 0.5 meter below the ground level is within the boundary of acceptable DoF at a horizontal distance of 10 meters from camera, therefore, roughly 60 meters above and 10 meters below the ground level will be within the boundary of acceptable DoF at a horizontal distance of 200 meters from camera.

    It is an absolute necessity to have a 'Fixed Mounting Platform' for both camera and Disto in order to measure accurately the needed distances for Lens Tilt. See Post # 77 for explanation and an example.


    My workflow using NuvoFocus for Lens Tilt:

    As I indicated earlier, I tether my DB to a Retina MacBook 13 for critical composing.

    1. Select a right focal length lens for the selected composition.
    2. Frame the image using whatever method you use. Tilt the camera if needed but no tilt of the lens yet. Review image on built-in display just to see if four edges are properly located.
    3. Fixed the camera height and the camera tilt (if you are using it). Measure and note the camera tilt angle and the Disto height.
    4. Aim at Near Object point with Disto laser point using Cube's pitch control. Measure X, Y location. Repeat the same for Far Object point.
    5. Reset the camera to the tilt angle that you noted before (so camera is again set for the desired composition).
    6. Enter the data into NuvoFocus; Disto height, camera tilt angle, camera focal length, near and far object location coordinates.
    7. Set Lens Tilt angle and the calculated Focus Distance (and Index Setting with Lens Equation) per NuvoFocus output.
    8. Take picture and review the composition.
    9. You may want to adjust your composition.
    10. Many adjustments can be done by 'shift R/L and raise U/D' instead of changing camera height or camera tilt angle. No adjustments are needed to the lens tilt or focus setting when you do 'shift'.
    11. If you decide to use different focal length lens, let say 47mm instead of 35mm to tighten the composition, only thing you have to do is to select other lens in the program. No new measurement are needed. Change the lens, adjust the lens tilt angle and focus setting, and shoot. You have another pin prick sharp image.



    Jae Moon
    Last edited by Jae_Moon; 28th August 2013 at 21:32.

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    Re: Talking Technical on Tech Cameras

    So Jae, when is the IOS version ready for sale? My Paypal balance needs to be used soon

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by jagsiva View Post
    So Jae, when is the IOS version ready for sale? My Paypal balance needs to be used soon
    Jag:

    Thank you for your interest. I am planning to announce the the pricing and methods of distribution and supports next week. Don't spend it all in 'HARDWARE'.

    Jae Moon

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    NuoFocus

    NuvoFocus is finally ready for release. It is a 'spreadsheet' that runs on any iOS devices, iPhone, iPad and iPod Touch, with an app, Numbers.

    It is available in four different modules:

    1. Nuvo_DoF: Performs DoF calculations.
    - Calculates HFD (for given focal length, aperture and CoC settings).
    - Calculates the DOF for a given subject distance (for given focal length, aperture and CoC settings).
    - Calculates the focus distance for given Near and Far DoF distance

    2. Nuvo_LE: Performs DoF calculations with Indexed Focusing with Lens Equations.
    - Includes Nuvo_DoF
    - Translates focus distance into an easy to use and highly accurate indexed focusing.
    - Supports both AS Rm and HPF (ALPA and Cambo) mounted lenses.
    - Standard Lens Equations are based on calibration data provided by both AS (laminated cards) or ALPA HPF lens data.
    - Special Lens Equation can be developed based on your own calibration (to complement or improve AS data) on AS mount only.
    - Developed with mathematical regression analyses to insure the accuracy in full range of focus distance, from 0.3 meter to infinity

    3. Nuvo_Tilt: Performs DoF and Lens Tilt calculations, with or without camera tilt.
    - Includes Nuvo_DoF
    - Calculates the required Lens Tilt Angle for both subjects on horizontal and tilted plane.
    - Calculates the required Lens Tilt Angle*with or without camera tilt.
    - Calculates the required focus distance setting required with Lens Tilt Angle.
    - Calculates the Boundary of Acceptable DoF, above and below the PSF (Plane of Sharp Focus), at any given distance from camera.


    4. Nuvo_Pro: Performs DoF, Lens Tilt calculation with Indexed Focusing with Lens Equations.
    - Calculates HFD (for given focal length, aperture and CoC settings).
    - Calculates the DOF for a given subject distance (for given focal length, aperture and CoC settings).
    - Calculates the focus distance for given Near and Far DoF distance
    - Calculates the required Lens Tilt Angle for both subjects on horizontal and tilted plane.
    - Calculates the required Lens Tilt Angle*with or without camera tilt.
    - Calculates the required focus distance setting required with Lens Tilt Angle.
    - Calculates the Boundary of Acceptable DoF, above and below the PSF (Plane of Sharp Focus), at any given distance from camera.
    - Translates focus distance into an easy to use and highly accurate indexed focusing.
    - Supports both AS Rm and HPF (ALPA and Cambo) mounted lenses.
    - Standard Lens Equations are based on calibration data provided by both AS (laminated cards) or ALPA HPF lens data.
    - Special Lens Equation can be developed based on your own calibration (to complement or improve AS data) on AS mount only.
    - Developed with mathematical regression analyses to insure the accuracy in full range of focus distance, from 0.3 meter to infinity.






    Please visit NUVOFOCUS.COM for more details and how to order. Contact us at [email protected]
    Last edited by Jae_Moon; 3rd September 2013 at 13:20.
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    Re: Talking Technical on Tech Cameras

    Jae, looks great. Couple of questions:

    1. So the Pro version includes all the bits?
    2. On your site, there is a reference for user configurable custom equations, what does this offer over the standard equations?

    Cheers...

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    Re: Talking Technical on Tech Cameras

    Quote Originally Posted by jagsiva View Post
    Jae, looks great. Couple of questions:

    1. So the Pro version includes all the bits?
    2. On your site, there is a reference for user configurable custom equations, what does this offer over the standard equations?

    Cheers...
    Jag:

    Pro includes all features with up to 3 lens equations. See the note below for lens calibration.

    Jae Moon



    Lens Calibration

    When I got my Rm3di, I was told that Arca-Swiss calibrates all lenses individually prior to shipping them to buyers. I don't remember if I heard it from A-S itself or by my dealer. I got SK35, SK47 and SK90, and the I was disappointed with the accuracies of calibrations; SK35 was good, SK90 was mediocre and SK47 was bad. Earlier this year, I received 'new and improved' calibration data from Rod, and it leads me to question the veracity of the claim, 'individually calibrated.' How can they have 'new and improved' calibration for my lenses without testing them? I believe it uses 'generic' lens calibration data. SOMEONE TELL ME IF I AM WRONG.

    I calibrated all my lenses by myself. It is somewhat time consuming but it worked for me. I made approximately 30 - 40 readings per lens at f =11, the half of the readings are between 0.5 and 5 meters, and the rest for 5 meters to 100 meters or so. I used the 'calibration cards' from A-S as starting points.

    For example,
    - Select a target at 1 meter (need not to be exact)
    - Focus the lens per A-S calibration and take picture
    - Move the focus setting +/- 0.5, then take picture.
    - Select the best focused setting
    - Move the focus setting +/- 0.2, then take picture
    - Select the best focused setting
    - Repeat until you get the best result.

    The calibration data provided by A-S for SK47 requires one curve fit at shorter focus distance range in addition to using 'modified lens focal length', however, my own custom calibration data requires three curve fits (for different focus distance ranges) in addition to using 'modified lens focal length.'

    Is it worth the time and effort? I could have lived with the generic data for SK35, but absolutely not with SK47.

    The standard 'Lens Equations' are developed from the data provided by Arca-Swiss, therefore, for example, all SK35s will have the same equation. The custom equation will be developed from your own calibration.

    Based on my 'limited' exposures of calibrating and analyzing data, in general, SKs have higher 'focus shift' than RDs, thus requiring better calibration for Lens Equations.


    FREE TRIAL VERSION IS STILL AVAILABLE. PM ME.
    Last edited by Jae_Moon; 4th September 2013 at 06:38.

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    Better method of calibrating lenses at Infinite subject distance

    There have been extensive discussions in this forum regarding the benefits of calibrating lenses at infinite distance with Tech Cameras. It has been recommended to calibrate them by picking a far but clearly visible stationary object for this purpose, 1,000 - 2,000 meters away if possible.

    The latest calibration cards from A-S for Rm camera have the calibration data up to 150 meters for all focal length lenses, and the ALPA HPF rings are calibrated to 47, 81, and 290 meters for SK35, 47 and 90, respectively. I was interested in knowing the magnitude of change in focus setting, even it may be small, between the factory maximum calibration distance and a real close to infinite distance setting, i.e. 1,500 meters.

    For example, the focus settings should be 0.48 and 0.02 for the distance of 150 and 1,500 meters, respectively, for SK47 with Rm3di using a lens equation. This difference may be translated to 5 angular degree of rotation, which is not an insignificant step change. You may get a different value from an actual infinite distance calibration (at approximately at 1,500 meter), but there still exists a step change.

    The advantage of having a lens equation is its ability to 'smooth out' the step change by making two or three additional 'far distance' calibrations, i.e., the readings at 500, 1,000 and 1,500 meters, and include them in making a lens equation. The calibrating distances do not have to be exact 500 or 1,000 meters, but known distance, i.e. , 545 meters, 980 meters, and 1,750 meters, etc.

    Then, the challenges are how to come up with accurate and known distance without using professional surveying equipment? The answer is Google Earth. I live in Annapolis, MD, and by using Google Earth I can locate several prominent landmarks in varying distances from river front park and find out exact distance between them. Google Earth has very accurate satellite images for almost all major metropolitan areas around the world.

    The screen shot below is for the subject 1,060 meter away from where I stood along Severn River, looking at the US Naval Academy.







    Jae Moon

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    Subscriber Member Georg Baumann's Avatar
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    Re: Talking Technical on Tech Cameras

    Jae,

    for someone who is new to tech.-cam's, this thread of your's is very valuable and highly educational. Thank you for the considerable effort in sharing your findings.

    I am surprised that none of the "big three" have contacted you yet on purpose to pick up and develop further your development. I can plenty of mutual beneficial synergies if Alpa, Arca Swiss or Cambo would cooperate with you. They could take care for the marketing aspects and sales, you could further develop and have available some more technical resources from the manufacturer etc..

    Best
    G
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    NuvoFocus

    Quick NuvoFocus Updates:


    - As all of you may know by now, the suite of iWork; Numbers, Pages and Keynote are available for free when you purchase a new iOS device. Each module can also be purchased at $10 from App Store for existing devices.

    - The standard Lens Equations that are included in Nuvo_LE and Nuvo_Pro will have an option to include 'infinity' calibration. You may include up to 3 calibrated measurement at no additional cost for each lens. See post #92 in this thread for detailed explanation.


    Jae Moon

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    Re: Talking Technical on Tech Cameras

    Jae,
    Thank you for your efforts on this calculator. I’ve been revisiting tilt calculations now that I’ve had some time in the field with my Alpa tilt adapter. I reread this post and it appears your spreadsheet will do something close to what I am interested in.

    Most of my photography is landscape. If you think about most of that type of shooting, there are a few “normal” conditions:
    1. We normally want the ground in focus from the point the scene gets rendered by the lens out to infinity.
    2. We normally prefer to level the camera.
    3. There is usually something, of some height and distance away from the camera we want rendered sharp.

    So these things add up to a few characteristics: the hinge line should be at or below ground, and the bottom DoF angle should maintain focus along the ground, i.e. be close or equal to zero (horizontal).

    If I use the ALPA Calculator drawing below as a reference (2nd drawing on the Tilt Calculations page), the points of interest are:
    Point 1: Entered by the photographer – Height and distance of subject. not necessarily on the lens axis as in the drawing, but this point along with point #3 defines the upper DoF line.
    Point 2: This point is not important because of the requirements of points 3 and 4
    Point 3: Calculated from camera height and lens coverage angle, and is the point at which the foreground comes into focus (equal to point 5 in the drawing)
    Point 4: Should be as far as possible, i.e. angle as close to zero (horizontal) as possible. Definitely needs to be greater than the subject distance, otherwise part of the “subject” will be out of focus. Of all the points, this one can have the most “give”, meaning it is what should change as the f-stop is increased.



    For example, I plug in the “coordinates” of Point 1 – height and distance, along with focal length and sensor definition including CoC, and f-stop. The calculator then figures the required hinge point and focus point that allows Point 1 to fall within the cone of DoF and the foreground that is in the lens's field of view, while maintaining the flattest, most horizontal bottom DoF angle. I can then experiment with smaller f-stops to see the best compromise between minimum f-stop and largest Point 4 distance.

    I am wondering if your spreadsheet could be useful for the above situation? Essentially calculating Point 5 and setting equal to Point 3 (I think your N DOF), then maximizing Point 4 with the most appropriate hinge point and focus distance. Or if I could take the outputs to create a matrix of tables...?

    Dave
    How glorious a greeting the sun gives the mountains! - John Muir

    davechewphotography.com

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    Re: Talking Technical on Tech Cameras

    Dave:

    Thank you for the inquiry, I will try to answer you as clearly as possible, however, the thought processes may differ between us.

    In addition to your diagram, please note attached diagram. It is an exaggerated representation of view camera in Lens (and/or Camera) Tilt application. I know many do not like to use camera tilt but it is needed in certain situations.



    Figure # 1


    In the application of Lens Tilt, there are GIVEN (or REQUIRED) and VARIABLES that a photographer can change.

    - Given is the Plane of Sharp Focus (PSF) which is defined by two objects you want to be in sharp focus. The plane intersecting these two points is the PSF.
    - The DIRECT variables are Camera Height and Lens Focal Length, and INDIRECT variables are Lens Tilt Angle and Lens Focus Setting.
    - Lens Tilt Angle and Lens Focus Setting with a Given PSF, selected Camera Height and Lens Focal Length are calculated.
    - We can vary the angle of the Wedge of DoF by changing the Lens Aperture Setting. The angle of the Wedge increase as lens aperture closes.
    - The Wedge of DoF is ‘Vertical DoF’ which extends from the hinge point to infinity, and all within that wedge are in acceptable sharp focus.
    - Therefore, a photographer would want to know the top and bottom of the Wedge vertically at any given distance from camera location.
    - A photographer needs to change Camera Height and/or Lens Focal Length if all important points of her composition are not within the Wedge of DoF.
    - Camera Tilt comes in the situation when Camera Height and/or Lens Focal Length changes do not bring all important points within the Wedge of DoF.



    Figure # 2


    My Workflow:

    - Identify two objects; Near and Far, to define the PSF.
    For example, a short Cactus flower in foreground and a tall Saguaro Cactus in background. I will pick the center of the Cactus flower as Near Object and about 2/3 way to top of Saguaro Cactus as Far Object. I am hoping to have the Wedge of DoF will envelop from top to bottom of Saguaro Cactus and short cactus flowers.

    - Determine Camera Height based on the selected Lens Focal Length for proper composition (Disto Height in Figure # 2).

    - Measure the location of two objects relative to the nodal point of camera lens (HOR/VERT & NEAR/FAR in Figure # 2).

    - Calculate the required Lens Tilt Angle and Lens Focus Setting (TILT ANGLE & FOCUS DIST in Figure # 2).

    - Check the location of Top and Bottom of the Wedge where short cactus flower are and where Saguaro Cactus is. See if both cactus are within the Wedge. Change the Aperture setting to adjust the angle of the Wedge (Note 1 of Figure # 2. For example, at distance of 10 meters from camera, PSF is at 1.28 meter above, the lower wedge is 0.5 meter below and the upper wedge is 3.04 meter above the reference level).

    - Adjust the Camera Height if needed.


    Dave, we are doing the same, but as I said earlier, our thought processes are slightly different. I start with what should be in focus while you want to setup your camera to maximize the Wedge of DoF along the cone of view of your selected lens.

    Hope I answered your question.


    Jae M

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    Senior Member dchew's Avatar
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    Re: Talking Technical on Tech Cameras

    Jae,
    Thank you! Your program looks to be a lot closer to what I think is necessary than some of the others out there.

    I do agree there is a subtle difference between how we are looking at this. I care a bit less about where the precise plane of focus is vs. what the DoF cone covers. I want to force the bottom wedge to be horizontal, then see if the top wedge covers what I need it to cover. If not, then I would enter a smaller f-stop until it did.

    But I see now that if I pick a point at the important distance, but only ~ 1/2 the subject height, essentially the same thing is accomplished.

    Ciao,
    Dave
    How glorious a greeting the sun gives the mountains! - John Muir

    davechewphotography.com

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