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Playing around with the Hy6

Guy Mancuso

Administrator, Instructor
We will just drink a lot that night so i don't feel the pain of the Voodoo needles.:ROTFL::ROTFL::ROTFL:


As you know making is right cost a fortune:wtf:
 

LJL

New member
We will just drink a lot that night so i don't feel the pain of the Voodoo needles.:ROTFL::ROTFL::ROTFL:


As you know making is right cost a fortune:wtf:
The only more problematic issue for you, Guy, may be missing both her birthday celebration AND wearing the numbers off your credit card(s) with even more toys you buy :bugeyes: :ROTFL:

Yep...making it right later is going to be expensive....but worth it :thumbs:

LJ
 
T

thsinar

Guest
LJ,

my file was PURPOSELY under-exposed, and I did not use any metering, but the histogram on the back's display.

It is always better, in a normal situation, to get the exposure on the spot, thus using the "best" part of the sensor's dynamic range.

This being said: when using the lightmeter, one has the possibility of 3 methods (average - centre weight - spot). Depending which one is set and how this is used, the metering can be completely out. Apart from this, I have made perfect exposed files when using it and "balance" as indicated in the display of the handle.

There is no "designed"/"built-in" under-exposure.

Best regards,
Thierry

My first reaction to your file, as well as to Thierry's garden shot was that things were leaning toward underexposure by a stop or more....

... The underexposure may be real and designed to prevent blowing things out, much like Nikon film cameras always were. Not a bad thing in the case of the Sinar files.

LJ
 

LJL

New member
Thierry,
I understand what you are saying. Thank you for the clarification on how the Sinar Hy6 and back record the meter reading. The use of the correct metering mode, and the placement of the metering patch is important to getting a proper reading for correct exposure. How sensitive those areas are (average, center weight and spot) can be critical. My own observations with different camera systems is that the meters are "tuned" to yield a best approximation for exposure, but some err more toward slight over-exposure, such as Canon has recently, while others may chose a slight under-exposure, as Nikon has for many years and models, even today. I am not suggesting that Sinar is doing the same, but it would not surprise me if their metering method had its own correction. That is fine if it does, and one just needs to learn a preference.

In David's shot, it looked as though the sky was dominating the reading, hence the darker image that showed what I would call under-exposure. What is interesting is that a larger portion of the image is actually a darker subject, so one could expect metering to boost exposure to compensate. If David was using area or spot and had selected a portion of the image with more sky, his original exposure looks about right....a couple stops dark to compensate for the sky. If he was using an average reading, I would have thought it to be a bit brighter overall to compensate for all the darker foreground, but that would just be a guess or speculation on my part, not knowing what kind of "pattern" for reading, and how sensitive each is on the Hy6 and Sinar back.

So, my apologies if it sounded as though I was attributing something to the Sinar kit that was beyond actual or design. It was just my impression from seeing David's image. Still does not take anything away from how robust the files actually are, and how much detail and DR they contain. That is all good. I know that you said you had purposefully underexposed your shot. My impression upon opening the RAW file you posted was that it was at least 2 stops darker, and it also already had some brightness applied already, so I was guessing total underexposure of nearly 3 stops. Only you know for sure what the real light was, and what you specifically metered, and I am not challenging that at all. I am merely giving my "guesstimate" of how much underexposure both images appear to have from my own experiences of working with lots of files (not Sinar).

Does that help explain my comment and set things a bit straighter?

LJ
 
T

thsinar

Guest
hi LJ,

nothing to apologize at all, and not even an argument between us: I do absolutely agree on your observations.

Some more information about light-metering, which are relevant when it comes to have a well-exposed file:

the first question one has to ask, is to what the actual (nominal) ISO is corresponding and related. There are of course ISO norms, but those are rather thought for the consumer field and leave open a big "playing gap". Therefore, the manufacturer has to decide by himself to what this ISO should be related.

When doing a lightmetering, the result should lead to a medium grey (Lab 50/0/0) rendered as medium grey. One has to be aware here, that a RGB medium grey does not necessarily correspond to 128/128/128, respectively a centered histogram does not necessarily lead to a correct exposure.

This is strongly depending on the Gamma value of the chosen Colour Working Space: in sRGB, a RGB value of 119/119/119 correspond to a medium grey. In ECI RGB, a medium grey is given with a value of 101/101/101.

The goal of the ISO sensitivity "finding" should therefore be to reach the above value for a medium grey, with ALSO taking in count the used "contrast curve". This has lead to the value of ISO 100 as nominal sensitivity for the eMotion 75, and ISO 50 for the eMotion 54 (resp. eMotion 22), with a "default" or "standard" contrast curve of "3" in Captureshop/eXposure.

When one makes use of a "linear" contrast curve, one typically "looses" 1/3 of a f-stop in the sensitivity.

Best regards,
Thierry





Thierry,
I understand what you are saying. Thank you for the clarification on how the Sinar Hy6 and back record the meter reading. The use of the correct metering mode, and the placement of the metering patch is important to getting a proper reading for correct exposure. How sensitive those areas are (average, center weight and spot) can be critical. My own observations with different camera systems is that the meters are "tuned" to yield a best approximation for exposure, but some err more toward slight over-exposure, such as Canon has recently, while others may chose a slight under-exposure, as Nikon has for many years and models, even today. I am not suggesting that Sinar is doing the same, but it would not surprise me if their metering method had its own correction. That is fine if it does, and one just needs to learn a preference.

In David's shot, it looked as though the sky was dominating the reading, hence the darker image that showed what I would call under-exposure. What is interesting is that a larger portion of the image is actually a darker subject, so one could expect metering to boost exposure to compensate. If David was using area or spot and had selected a portion of the image with more sky, his original exposure looks about right....a couple stops dark to compensate for the sky. If he was using an average reading, I would have thought it to be a bit brighter overall to compensate for all the darker foreground, but that would just be a guess or speculation on my part, not knowing what kind of "pattern" for reading, and how sensitive each is on the Hy6 and Sinar back.

So, my apologies if it sounded as though I was attributing something to the Sinar kit that was beyond actual or design. It was just my impression from seeing David's image. Still does not take anything away from how robust the files actually are, and how much detail and DR they contain. That is all good. I know that you said you had purposefully underexposed your shot. My impression upon opening the RAW file you posted was that it was at least 2 stops darker, and it also already had some brightness applied already, so I was guessing total underexposure of nearly 3 stops. Only you know for sure what the real light was, and what you specifically metered, and I am not challenging that at all. I am merely giving my "guesstimate" of how much underexposure both images appear to have from my own experiences of working with lots of files (not Sinar).

Does that help explain my comment and set things a bit straighter?

LJ
 

fotografz

Well-known member
Still learning this new kit folks so don't expect the best that this back has to offer yet. Anyway, went down to the train bridge this evening to see if I catch a good sunset but no dice. So I shot the bridge instead. This first shot was underexposed by about two stops. So I bumped exposure up by two stops in Aperture to see the level of detail that was available. The third shot is a crop of the second to show the detail. My early impression is that this back generates excellent files that can be pushed hard in processing. A valuable feature for me :)
David, as I am still seriously considering this whole end of the spectrum to replace my RZ/Hassey-V 6X7/6X6 systems for studio and some location work (the H3D-II/39 645 will remain in the arsenal) ... I have a few questions.

In the 3rd detail image you posted there is noticeable red fringing on the edge of the sign and other areas where the sky butts up against a darker edge. What lens was used for this shot and what are your thoughts concerning this?

I ask this because it is an issue that can present itself when using strobes to back light products, and can also manifest itself when shooting items with specular highlights like jewelry or many highly finished industrial products ... all of which are frequent assignments I would be using this gear for.

For example I just completed an assignment shooting a bunch of 2009 GM wheels that all had to be backlit to knock out the neg. areas because they would be appearing on a white catalog page. CA or color fringing is not an option even if correctable in PS because the quantity of images precludes such additional labor... and the client has an eagle eye for such things.

I would show you an example of this except I need prior approval because of a non-disclosure agreement ... these are 2009 products not yet public.

Your thoughts?
 

David K

Workshop Member
Marc, the lens that was used for this capture was the 80 2.8 PQS that comes with the kit. My feeling about the color fringing you refer to is that this is a poor image to judge whether this would present itself in your application. I say this because the image is seriously underexposed and, for example, the color fringing in the netting protecting the light on the far right of the image does not show in the image prior to the exposure adjustment, which leads me to believe that if you had a properly exposed image you might not have this issue at all. If you will suggest a test shot that would better address this issue I'll be happy to take it for you and post the results...
 

Guy Mancuso

Administrator, Instructor
We can do this in San Juan also when David and i are together and actually shoot a side by side of the same scene with a P45 plus , P25 or P30 plus and my ZD backs.

David we can shoot a corner of a building against a sky and expose for the shadows and see if we get fringing on the edges of the building. Or the same thing with trees into the sky looking up. Two really good test for fringing
 

irakly

New member
marc, chances are, you won't be using the 2.8/80 planar for this. the lens of choice is schneider 150 apo-symmar, which is just as good as contax 120 apo makro. no fringing, unless it comes from the back :)

David, as I am still seriously considering this whole end of the spectrum to replace my RZ/Hassey-V 6X7/6X6 systems for studio and some location work (the H3D-II/39 645 will remain in the arsenal) ... I have a few questions.

In the 3rd detail image you posted there is noticeable red fringing on the edge of the sign and other areas where the sky butts up against a darker edge. What lens was used for this shot and what are your thoughts concerning this?

I ask this because it is an issue that can present itself when using strobes to back light products, and can also manifest itself when shooting items with specular highlights like jewelry or many highly finished industrial products ... all of which are frequent assignments I would be using this gear for.

For example I just completed an assignment shooting a bunch of 2009 GM wheels that all had to be backlit to knock out the neg. areas because they would be appearing on a white catalog page. CA or color fringing is not an option even if correctable in PS because the quantity of images precludes such additional labor... and the client has an eagle eye for such things.

I would show you an example of this except I need prior approval because of a non-disclosure agreement ... these are 2009 products not yet public.

Your thoughts?
 

gogopix

Subscriber
Still getting the feeling that the HB/H3D and Hy6 are in the "studio" camp while the Contax, Mamiya and even HB V are more 'outdoor' cameras.

David, am I wrong? but you have had the Contax, yes? isn't this quiyte a handful compared to that?

In fact, as I look at these backs and cameras, the more I think it is the glass and feel that dominate, rather than other features, for outsidew work.

The flash synch, WB, 'look' etc seem pretty much the same.

For IQ, it will come down to glass

For usability, it will come down to easy of handling..

Everytime I pick up the Contax it just makes me so #%^%%$%^ mad that nobody is picking it up.

Ah well, at least the Sinar has a C645 mount and can be mounted on the Alpa (yes??)

I may just go that route. I do then have the option of the Dalsa vs Kodak (I do think thgere are trades that the board cant eliminate)

So, who's got a deal on a SInar for me!!??

Victor
 

gogopix

Subscriber
:ROTFL::ROTFL:

Absolutely nothing! (but don't tell anyone)

But I do have a second Contax body sitting there and I was looking for a backup
maybe a sinar
maybe the 30+

Actually, I am tired of swapping the back (the P45+) from my Alpa, and I am ready to invest in some more lenses. T^he idea is to have the C645 with faster lenses (incl HB) and a higher Iso back for interiors on travel, and then keep the P45+ on the Alpa with Schneiders for high res, outside and trekking. Often I can get6 around town, the catherdrals etc with anything, but need something lighter for the trail. If I can get a decent rangefinder I am actually thinking of t6rekking with the ALpa TC and a 24/35 and 47/60 (much lighter than comparable C645 lenses) and use the C645 with C and HB V (like the 180, or 40 or 110/2) for town work.

Regards
Victor
 

lance_schad

Workshop Member
Victor,
You can just get another Phase back in the Contax mount and use it between your ALPA and Contax, thus having one work-flow and one set of batteries. You have been satisfied with the Phase-One image quality after all these years?
Plus if you go for a P30+ for your Contax system you will have up to 1600iso.
Just my 2 cents.
L
Lance Schad
Capture Integration - Miami/Atlanta
305-394-3196 cell | 305-534-5702 office
Capture Integration
My Blog
[email protected]
 

gogopix

Subscriber
Lance,

Yes that's the trade. What would be good would be an underexposed shot, at 1600 ISO on the P30+ to compare with the new board 74LV.

I say underexposed, but only part needs to be. I would like to 'push' similar to the 74lv shot. In that, I was able to push 3 stops beyong 800 for an equivalent ISO 6400 . Pushing the P30+ by 2 stops would be the same.

I will give Phase the better resolution, and workflow. It's all about getting the high ISO.

Now in the case of the P30+ the 74lv has the advantage (31/33 MP? yes?) Then again, the P30+ is considerably cheaper, no?
Victor
 

David K

Workshop Member
David, am I wrong? but you have had the Contax, yes? isn't this quiyte a handful compared to that?
Victor
Don't know where you got that impression Victor but these pics should answer it for you. Contax has RRS L plate and prism finder making it larger, film back is obviously smaller than digital back. Hy6 has a RRS plate on the bottom as well. Both with their respective 80mm lenses. The Sinar is obviously smaller but when you change lenses, e.g. 110 F/2, the Sinar can catch up pretty quick weight-wise
 
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