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Thread: Tech Cams, Cubes and Tilts

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    Tech Cams, Cubes and Tilts

    -- Cambo 1250 w/ Rod 40 TS; Arca C1

    i) The spirit levels on my cube don't appear to agree with those on the camera body itself. Would this mean that there's likely an issue with the mounting plate?

    ii) I've been shooting buildings thus far using what seems to be a relatively foolproof f/11 and focusing to infinity. Out of curiosity - what's the 'short' side of infinity with this lens? Would I be better off trying to find the hyperfocal distance on the barrel and leaving it at that/would it give me a little more breathing room?

    iii) On the IQ380: what constitutes as a long exposure/when should I be enabling noise reduction?

    iv) Will shooting shots of 1-2s in duration cause image degradation if I do say.. five in a relatively short time frame with the back heating up?

    v) Is there a way to calculate how much tilt is required (with respect to the indicators on the cube) when aiming higher/lower than the horizon?

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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Tech Cams, Cubes and Tilts

    Quote Originally Posted by colorspace View Post
    -- Cambo 1250 w/ Rod 40 TS; Arca C1

    i) The spirit levels on my cube don't appear to agree with those on the camera body itself. Would this mean that there's likely an issue with the mounting plate?

    ii) I've been shooting buildings thus far using what seems to be a relatively foolproof f/11 and focusing to infinity. Out of curiosity - what's the 'short' side of infinity with this lens? Would I be better off trying to find the hyperfocal distance on the barrel and leaving it at that/would it give me a little more breathing room?

    iii) On the IQ380: what constitutes as a long exposure/when should I be enabling noise reduction?

    iv) Will shooting shots of 1-2s in duration cause image degradation if I do say.. five in a relatively short time frame with the back heating up?

    v) Is there a way to calculate how much tilt is required (with respect to the indicators on the cube) when aiming higher/lower than the horizon?
    #1) Pretty common, in fact there are a number of threads here at GetDPI about the futility / measures required to match levels on the head, tech cam body and MFDB. Ultimately it's easiest to pick one set of levels and just keep with it.

    #2) You can use a DoF calculator using the chip CoC for the IQ380 - sorry I don't know the exact CoC to use for the IQ380 but I'm sure that someone here can give you a number. In the past the most picky CoC was calculated as something like 1.4x the sensor pitch (sqrt 2 x pitch), but only you can decide what really gives you acceptable sharpness ahead of hyperfocal distance. The best thing to do is perform your own tests by measuring a number of focus distances around hyperfocal and comparing infinity results and foreground detail results to come up with your 'preferred' hyperfocal distance.

    Btw, photopills recommends 10ft for IQ280 & Rodie 40HR @ f/11 for 5ft to infinity.

    #3) The back will do it's own dark frame processing as required dependent upon a number of factors such as ambient heat, exposure time, etc etc. You don't need to do anything yourself unless you intend shooting exposures of several seconds (my IQ260 used to kick in with a warning if more than 10s).

    #4) Unlikely unless you are using the back in zero latency mode.

    #5) Get yourself a copy of the Snapi lens tilt iPhone app and you can measure the tilt of the body/back and hinge line height and get recommended tilt angles for the lens. Highly recommended if you want to just dial in tilt using the math vs live view focus/adjust.
    Last edited by GrahamWelland; 2nd January 2016 at 02:42.
    Remember: adventure before dementia!

    As Oscar Wilde said, "my tastes are simple, I only like the best"

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    Senior Member kdphotography's Avatar
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    Re: Tech Cams, Cubes and Tilts

    You could also have John Milich pimp your Cube. http://www.getdpi.com/forum/medium-f...brication.html
    I believe you can also calibrate the dual axis level in the IQ MFDBs.
    I think it best to simply stick to one of the leveling standards, and not worry too much over the camera body level vs. cube level vs. IQ levels not being exactly in harmony. Most of us here in Dante's Inferno aren't exactly perfectly level in the head either. It just depends on who's asking...

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    Re: Tech Cams, Cubes and Tilts

    i wanted the cube levels to be accurate; not only that, when they read level, i want the panning axis to be dead plumb. this way, you should be able to retain perfect level, both ways, of the film plane when rotated in 90 degree increments

    and then, when you clamp your camera onto a leveled cube with plumb rotation axis, the film plane should also be plumb and level.

    good luck with that, as there are several interacting "machined" surfaces that are not all perfect.

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    Senior Member stephengilbert's Avatar
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    Re: Tech Cams, Cubes and Tilts

    I believe you can also calibrate the dual axis level in the IQ MFDBs.

    Sure: you just take it into the back room at RRS and put it on the level table.

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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Tech Cams, Cubes and Tilts

    Quote Originally Posted by stephengilbert View Post
    I believe you can also calibrate the dual axis level in the IQ MFDBs.

    Sure: you just take it into the back room at RRS and put it on the level table.
    Indeed yes you can

    Quote Originally Posted by kdphotography View Post
    . Most of us here in Dante's Inferno aren't exactly perfectly level in the head either. It just depends on who's asking...
    What Ken said!
    Remember: adventure before dementia!

    As Oscar Wilde said, "my tastes are simple, I only like the best"

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    Re: Tech Cams, Cubes and Tilts

    Steve: all that will do is confirm the camera (or cube) base is as level as the surface plate they use; not a bad requirement, of course.

    so if you put your cube on their plate, you are still not confirming anything about the top of the cube, the clamp, that holds the camera

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    Re: Tech Cams, Cubes and Tilts

    The best way I have found to solve his is to use the iPhone's Levels feature in the Compass app. I stand it on the top of the Rm3DI and then hold it by the side against the back of the camera body. Once I have centered in both planes by adjusting the Cube or the tripod I then calibrate the IQ back's level utililty. It doesn't entirely solve the problem of rotating the Cube for a stitched pano but I tend to use lateral shift for this.

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    Subscriber & Workshop Member GrahamWelland's Avatar
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    Re: Tech Cams, Cubes and Tilts

    Quote Originally Posted by jlm View Post
    Steve: all that will do is confirm the camera (or cube) base is as level as the surface plate they use; not a bad requirement, of course.

    so if you put your cube on their plate, you are still not confirming anything about the top of the cube, the clamp, that holds the camera
    Steve was referring to the task I had RRS do for me when we visited a few years back. For most of us, finding something calibrated to be level is a challenge and so getting at least one part of the system, in this case the MF body, set level on a plate was the goal. That way the cube and body levels could be ignored (although the levels in the Alpa STC did prove to be correct too although the Cube never did). I agree that it did nothing about proving out the accuracy of the Cube levels as you can appreciate given the amount of work it took you to correct for the design and manufacturing tolerances of the Cube itself and their glued in levels.

    Of course even getting the back set to a known level was an exercise in frustration as the built in Phase One leveling would drift anyways after a while .

    Eventually I learned to chillax, pick a level somewhere on the system, shoot a little looser and fix it in Capture One later.
    Remember: adventure before dementia!

    As Oscar Wilde said, "my tastes are simple, I only like the best"
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