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IQ180 with Phase One DF camera-colour issue

Guy Mancuso

Administrator, Instructor
Just another data point check your color editor as well and make sure nothing is selected. Your just to far off the mark here so something is off somewhere in the chain. Also when you post here on the forum make sure you are SRGB. Also check your red channel in C1
 

gazwas

Active member
Which camera profile are you using, flash or daylight? (Note that "daylight" truncates and bumps red and blue saturation and flash is a larger space and more even, and more accurate.
Jack, I always thought it was the other way around and "Outdoor Daylight" had a larger more accurate colour space than "Flash". :confused:
 

Jack

Sr. Administrator
Staff member
One other thing came to mind -- on import, make sure you are not applying a style or doing an "auto correct"
 
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GeoffRoss

Guest
First of all, thanks so much for all the suggestions!

Jack, I have now tried most of what you have suggested, except one, which is how do I check the red channel in Capture One? I have to admit I don't know where or how to do that in the program.

On checking all the other things, and changing them to the various options suggested, the result is pretty much the same. However, I am glad you agree that something is wrong, as it definitely is. I did send an email to Phase One about it, but so far only a confirmation that they received it.

I also contacted my local dealer, and he suspects that because I am using a very recent 12 core Mac, that there is likely a bug that hasn't been addressed yet. A few months ago, prior to the latest upgrade in Capture One, there were a lot of issues.

How can I edit the camera profile? I think that might be a solution.

Regards,
Geoff
 

Jack

Sr. Administrator
Staff member
Geoff:

You can edit the camera profile using color editor under the advanced tab. You select red then dial saturation back to an acceptable level. Actually, you could shoot a MacBeth and then build a new profile by setting everything exactly. Anyway, once you have all the colors the way you want, you can save it as an icc profile -- call it IQ180_DL_adjusted or whatever and then select it in the camera profile dropdown.

However, BEFORE you do any of that, have you processed both files and opened them in CS? And if so, do they still have the same difference? I suspect they will not, that the one showing saturated reds is going to look "right" in CS. That would tell us that is is how your system is rendering the preview and not an actual color issue on output. If not, then for sure, build a corrected profile per above...
 
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GeoffRoss

Guest
Jack,

Thanks very much for the information on how to edit the camera profile.

Yesterday, before I even posted anything on this forum, I had already processed images, and yes they reflect exactly what I see in Capture One. The saturation in the reds is pretty close to being -20 (which is a LOT!) on all images containing this red spectrum. At least it is consistent! I am just about to take my gear into the dealer, and we are going to check out my images on his computer. He feels that it is a problem Capture One has with the Mac 12 core computer, and after seeing the issues prior to the last couple of upgrades, I tend to agree that it is a very strong possibility.

I will post the results of my meeting with him later on, so that others can profit from it.

Regards and thanks very much again,

Geoff
 
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GeoffRoss

Guest
I have just returned from my dealer's premises, where we performed a number of test exposures on 3 different backs, 2 IQ180s and 1 65+, plus we now have viewed the results on two totally separate and different Mac computers. The bottom line is that there IS a problem in Capture One in accurately rendering reddish-browns and orange-reds.

If you all do the same test you will find the same results as we have. My dealer is today putting together a formal case to ledge to Phase One.

Regards,
Geoff
 
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GeoffRoss

Guest
Jack,

Both the dealer and I use the latest version of Capture One, and he also checked back on the last couple of versions, and they too have the same issue. It really is surprising that noone has reported it to Phase One, or else they haven't acted upon it yet.

The tests we did this morning really prove that there is an over saturation of the red-brown and orange brown spectrum. If you do some tests photographing similar colours whether they be bricks or whatever that you are familiar with, I am pretty certain you will see the same over saturation as well.

Regards,
Geoff
 

gazwas

Active member
Jack,If you do some tests photographing similar colours whether they be bricks or whatever that you are familiar with, I am pretty certain you will see the same over saturation as well.
Geoff sorry, I'm just not getting the results that you are.

The reds might be a bit too saturated but that could be to do with WB or exposure as the building looked 95% as it is in the image below.

700px square crop from a P65+, Schneider Digitar 120N, daylight WB and ICC profile straight out of C1 6.2.1 as sRGB jpeg 80% on an 8 core Mac Pro OSX 10.6.8.
 
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GeoffRoss

Guest
Gareth,

You say that "the reds might be a bit too saturated", so you are actually confirming what the results we are also getting. The fact is, we proved quite conclusively this morning that there is indeed an issue with Capture One's rendering of the brown-red spectrum, and Phase One really need to address this. We checked the 3D imaging of their colour gamut, and there is indeed a spike in the reds, which corresponds to the saturation I have been speaking of.

Regards,
Geoff
 

gazwas

Active member
Yes and No! ;)

I'm saying the reds look fine but if being very critical they are slightly over saturated but look in reality 95% as they do in the attached shot. In other words nowhere near as saturated as your attached image.

Put it this way, if you had not posted this question I'd never have noticed anything wrong as with my results its so minor.
 
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GeoffRoss

Guest
Gareth,

That image I posted is absolutely typical of the results I have seen in the past couple of days, with every image that has the reddish brown and orange-red colour. There has been no exception. This has also been using different backs, and on another computer as well. The dealer concerned has a great deal of knowledge in the workings of Capture One, and he had to conclude that yes there is an issue that needs to be rectified.

Regards,
Geoff
 
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GeoffRoss

Guest
Tim,

This is an entirely different sort of issue, and one that is not related to a particular back, but a problem with the Capture One software, and in particular the over saturated rendering of certain reddish tones. It's not a major serious problem, as it can be overcome by corrections in the colour editor, yet one that really ought to be fixed for such a high end product.

Regards,
Geoff
 

cunim

Well-known member
Geoff, I shot some bricks with my IQ/C1 on the PC. Appears to me that there is no trace of red oversaturation at normal exposure, but that the proportion of red becomes nonlinearly higher with underexposure. The left image is slightly overexposed and looks very like the real thing. Slightly undersaturated if anything. The right image is underexposed by 2 stops and then raised in LR. Note the proportional increase in the red component. I would guess the QE of the chip is higher in the red and this is not being well compensated in C1. Just a guess.
 
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tashley

Subscriber Member
Tim,

This is an entirely different sort of issue, and one that is not related to a particular back, but a problem with the Capture One software, and in particular the over saturated rendering of certain reddish tones. It's not a major serious problem, as it can be overcome by corrections in the colour editor, yet one that really ought to be fixed for such a high end product.

Regards,
Geoff

On reflection I agree on both fronts: I've never had a problem with it myself but you probably have more sensitive colour vision in this part of the spectrum and I can clearly see from your examples that it looks odd.
 

Jack

Sr. Administrator
Staff member
Sorry, but I am not seeing it Geoff. I went home today and ran a quick test on my brick walkway. This is the IQ180 back on the Phase DF body and 110 LS lens at f8, using the indicated body exposure of 160th at ISO 35, f8. I pulled them into C1 and they looked fine -- note they did NOT look fine until they finished rendering, and the red is over-saturated at that point in time, but that is typical -- after a few seconds they render and look proper. Anyway, I applied my basic style on import which uses Outdoor Daylight profile and bumps saturation 4 points. I returned sat to zero and did a dropper WB off the second white patch on the color checker which cooled the image down 50 K and about 2 points on tint from my style to 5130/-2.6 in Profoto color space. The center weighting of the camera under-exposed by about 1/3 stop for Profoto (typical) so I bumped it up in post to compensate. That's it.

Here you go, basically neutral out of the cam, but properly converted to sRGB for web view --- and this is exactly how my bricks look next to my (rather sad) drought dried California lawn:



Here is a close-up of the CC, and if you mouse over it with your dropper, you will find the grays are a few points off from each other, but still quite close, and that is a result of compressing Profoto into sRGB, not the camera profile:




So, in conclusion, I think you must have some other equipment profile issue, or possibly the way you are converting your images to web view is improper.

Sorry,
 

Jack

Sr. Administrator
Staff member
Jack, I always thought it was the other way around and "Outdoor Daylight" had a larger more accurate colour space than "Flash". :confused:
You are correct -- my mistake! I will edit and correct what I wrote above -- thanks for pointing that out!
 
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