CMOS vs CCD and colour profiles a quick and dirty comparison

[ErikKaffehr]

Hi,

As it happens, most photographers who's work I am familiar with use Lightroom. I would guess that vision, knowledge, subjects and workmanship are far more important than choice of tools. I would suggest that most photographers use Canon cameras and Lightroom so Canon and Lightroom are probably properly represented in any choice of great pictures.

A small point I would make is that experience matters. You find a way of processing your images. Learn what seems to be the best way to make the best of the tools you have at hand.

Best regards
Erik

Bart,

 I'm sure you're right. As for me - I simply don't use Lightroom
 Not using Lightroom is the single quickest way to make one's pictures better - if one can locate them

Edmund

[ErikKaffehr]

Hi,

Here are raw files from the P45+ / A7rII shot: http://echophoto.dnsalias.net/ekr/Articles/Colours/Raws/

I will post the calibration images later.

Just to make it clear, the intention with this thread is to discuss what differences are due to processing (that is profiles) and what is due to sensors. I would very much like to compare different sensors, but the samples I publish are based on the stuff I actually own.

According to Anders Torger's writing both the P45+ and the A7rII are difficult to handle. Oversaturation on the P45+ and excessive sensitivity in blue on the A7rII.

Tim Parkin and Joe Cornish say that the P45+ produces yellowish greens that are difficult to handle. I have this from Tim in writing but he makes it very clear Joe Cornish have the same issues. They also say DALSA based Phase One does not have that problem.

I guess that some may see it yellowish greens as a benefit, it is a warm and therefore pleasant reproduction.

Best regards
Erik

[eronald]

Erik,

 This happens to be one of the rare places where a majority of people might agree if I say "LR has nice workflow, but if you want good quality conversions, C1 is much better, especially for Phase files, and especially when it comes to color". I know people like to disagree with me, but I fear for once I might have both Synn and Doug at my side

 I hate LR conversions, although I love PS as a Tiff editor. There was a time when I ran every Canon image through LR automatically with a script, but when I wanted to do a large print I would use DPP.


Edmund

Hi,

As it happens, most photographers who's work I am familiar with use Lightroom. I would guess that vision, knowledge, subjects and workmanship are far more important than choice of tools. I would suggest that most photographers use Canon cameras and Lightroom so Canon and Lightroom are probably properly represented in any choice of great pictures.

A small point I would make is that experience matters. You find a way of processing your images. Learn what seems to be the best way to make the best of the tools you have at hand.

Best regards
Erik

[ErikKaffehr]

Hi Edmund,

Here is the P45+ image processed by both Capture One and Lightroom.

Adjustment, WB on grey card shots on both. LR +0.33EV C1 -0.4EV.

LR using profile created by DCamProf while Capture One using default P45+ profile.

Capture One uses the "film curve", which is default rendition. That is probably causing the exposure difference.

First crop: C1 (tiff file, on top)
Second crop: C1 (tiff file on the left)

Both processors do a lot of stuff under the hood. It is a bit easier to generate DCP profiles for Lightroom than for C1. That is the main reason I use LR for this comparison.

I will do the same comparison using RawTherape.

Best regards
Erik

Erik,

 This happens to be one of the rare places where a majority of people might agree if I say "LR has nice workflow, but if you want good quality conversions, C1 is much better, especially for Phase files, and especially when it comes to color". I know people like to disagree with me, but I fear for once I might have both Synn and Doug at my side

 I hate LR conversions, although I love PS as a Tiff editor. There was a time when I ran every Canon image through LR automatically with a script, but when I wanted to do a large print I would use DPP.


Edmund

[ErikKaffehr]

Hi,

What I may see is that I get more yellowish greens from the P45+, even when using DCP-profiles generated by DCamProf. In these cases I tried to do everything the same way, but there are some room for mistakes. One of the first mistakes was that I didn't have my WB card with me, so I need to get WB off a different shot, made something like 30 minutes later.

Using Capture One gives more yellowish greens on the P45+ than Lightroom with my profile.

So, what I see is that the P45+ back may render grass more yellow than the Sony A7rII I compare to. That is a bit consistent with some writing by Tim Parkin, who says that P45+ has issues with reproduction of chlorophyll greens. That could be an IR-filtering issue, as chlorophyl has high IR reflection.

If we check the flower crops I would say colour is pretty close, so I think that the colour profiles take good care of that part.

On Landscape (the Tim Parkin's on line publication) is unreachable right now, but here is what he said about P45+ colour in an e-mail to me:

"I'd love to try to get some good metamer pairs to test sensors with but it's tough finding good information about them. DxO use color checker targets for this and they don't realy work and I think they'we working with illuminant metamerism anyway. It's an 'indication' but not fact.

I spoke with Joe about the P45 endlessly and he had a whole workflow to try to 'fix' the colour which all went out of the window when the IQ180 came in. He now does almost nothing to the files to get what he wants. It's definitely mostly grassy stuff but quite often skies and reflected colour that are problematic. Also shadows in geology can be an issue (I presume infra red effects as well).

They're not a problem for some subjects and an absolute nightmare for others. I can still 'see' Joe's P45+ files as long as they have some greenery in them (or sometimes from the sky).

I'll have a think again about metameric pairs"

Joe is Joe Cornish, a well known British landscape photographer. He is presented in some of Phase One's marketing videos. The P45+ has a Kodak Sensor while the IQ 180 has a DALSA sensor.

Best regards
Erik

[ErikKaffehr]

Hi,

What i have observed from the experiments on this thread I would say that the first experiments, based on DT-s table top setup sort of indicated that profiles can by and large handle potential differences between DALSA CCD and Sony CMOS.

In my field shots using P45+ and Sony A7rII it may be differences that simple profiles cannot handle. It is possible to tweak profiles a lot, of course.

The major difference I have noticed was that the grass had a yellow tint on the P45+ shots. This was even more pronounced in Capture one processing.

So, what does this mean for an MFD buyer? Not so much. I would say that it is probable that CMOS and CCD can deliver similar colour with good profiles. But MFD shooters use vendor software, mostly, and in that case they get the profiles "The Image Quality Professor" develops or his colleague at Hasselblad. Pentax 645Z and Leica S shooters seem to be happy with their cameras, mostly shooting Lightroom.

Lightroom has a lot of profiling options.

With DCamProf we can generate profiles for both DCP and Capture One and those profiles are probably very good.

Best regards
Erik

[torger]

I'm one of those that think Capture One's color is overrated, and I'm sure that's one reason some have chosen Hasselblad over Phase One despite the more primitive backs and software.

Phase One has this thing about putting a yellow cast over everything, and I just don't think that's the right thing to do. Hasselblad does put a little bit warmth in there, and in my own subjective profiles I do put a little warmth into yellows and greens, but to a much lesser extent and less global than Phase One's profiles.

I can't deny that the profiles are really well made in terms of technical design, but I personally don't agree with their choice on how to render colors.

It's hard to discuss colors without having images to show though. What's is a "huge" difference to one person can be "small" or even not detectable to another. I'd love to see image examples of the color issues Tim mentions, and try to figure out if it's a profile issue or a CFA issue.

[synn]

I know what you mean by the "Yellow cast". it's quite subtle and it works for many scenarios, but if you don't like it, you can automate the 3 way color editor to your liking.

[torger]

Here's an example of what I think is a suitable addition of warmth. The first is a neutral rendering, and the second is with my own subjective look. At first glance they may look identical, but layer them on top and do a A/B swap the difference is quite easily seen. This level of difference is what I call subtle, and I think Phase One is way past that.

Unfortunately I did not have the original Phocus rendering left so you just have to take my word that the yellowness in that pretty much matches the yellowness in my subjective rendering.

I think the "color memory" of an sunny early evening is that the sunlight is somewhat yellow, and if you render a scene neutrally it becomes a tiny bit too cool, the sunlight looks too white. However I see little reason to apply yellowness to a blue sky for example, so warming up the green-to-yellow range I think is the right way to do, but stay out from the shadows which could stay neutral or even be cooled down a bit.

My intention when making a subjective look in a profile is to make it "look right", sort of a more neutral than neutral. The task to add a strong personal look I think should be left to the post-processing workflow, but there are of course different preferences.

[LDJ]

I totally agree that Capture One's colours are totally overrated. I find the yellow/warm cast pronounced and a real headache to deal with in many images; I shoot predominantly interior lifestyle and getting neutral paint colours to look right without other elements in images being adversely affected can be very tricky. The yellowing of greens in landscapes is also not a look I like (particularly when it is as pronounced as it was with my old P45+ back). On some jobs I have resorted to using Canon's DPP/Lightroom to process the files as they give much more neutral starting points, without a warm cast. Colour accuracy with C1 Pro is also poor in my view: try capturing a selection of fabrics showing vibrant and varied colours and getting accurate colours using C1 Pro without many adjustments using the Advanced tab of the Color Editor...

Although I don't have a need to shoot with digital backs as much these days, I am hoping that Phocus is improved just a little more, e.g. the addition of perspective tools which I need when tethering in front of clients/collaborators, so that I can start using Hasselblad backs instead of Phase, as I find the Hasselblad colours much better and the overall look far more neutral. My understanding is that Phase wanted to create a 'pleasing' look with it's colour rendering choice but, in my opinion, the aim should be for accurate and neutral colours as a starting point; leave the subjective colour to the photographer.

Best

Liam

[Christoph B.]

Interesting. I found the opposite to be true - Lightroom always gave my files a warmer tone while CaptureOne creates neutral images without any colours shifts.

Perhaps it's the profile of the P45+? I'm using a P65+ and that has a different sensor and profile. Or maybe it's an issue of white balance? Do you use grey cards or other means to get your WB right? And what about your screens - are they calibrated? And if so - how?

[LDJ]

Hi

When comparing C1 Pro with Lightroom, I'm specifically referring to my Canon files as I never processed my P45+ files (or files from any other Phase backs I have used) with any program other than C1 Pro. I always use a grey card (normally X-rite) and have a hardware calibrated Eizo monitor. I'd be interested to know how Phase create their colour profiles because the files have a warm cast even though the patches on grey cards show equal RGB numbers; it is almost as though Phase make sure that true neutral greys stay neutral whilst giving a warm cast to all other colours.

Perhaps users of other brands will have a different view on C1 Pro's colour rendering.

Best

Liam

[torger]

When you design a warm look you still need to keep the neutrals neutral, otherwise it's just a white balance offset. So yes the warm look often seen in Capture One is a designed look, it's not just a white balance offset. I'm not sure if all cameras are affected and to the same amount, C1 supports hundreds....

When working with my profiling software I saw results from P45+ and IQ260 which both had that tendency towards yellow. Obviously many like it, and it's not bad for a camera company to have a look that the customers identify with so they stay loyal to the brand. Leaf has a distinct different look from Phase One, and indeed some choose Leaf for that reason, and not only because of the more attractive price.

Partly to break free from "brand looks" I started to make my own profiles so I can more easily move between brands without significantly changing the look of my images.

I've tried more profiles from Lightroom, and they can vary quite much in look. A clear example is the desaturated look in A7r-II and Pentax 645z profiles and some others that are not mirrored in other of their profiles. Lightroom also provides extra profiles for the more popular cameras that contain looks that is supposed to mimic the manufacturers own profiles if I got things right, I have never made a comparison myself so I don't know how close they are.

[LDJ]

That makes sense to keep the neutrals 'neutral'; I find the fact that it is possible to keep greys neutral all the way from the shadows to the highlights, whilst giving an overall warm look to images, interesting. I often find myself using the Color Balance wheels in C1 to compensate for the yellow cast; this helps to create a more neutral looking file overall in many cases but naturally means that the greys are no longer perfectly neutral 'by the numbers', and there are times when this causes more issues than it solves.

Anyway, I guess the colours out of C1 are what they are and it is unlikely that Phase is going to change its approach to colour rendering any time soon...

L

[eronald]

Agreed.  The problem is that the difference appears to be almost entirely in saturation, which appears to have become an arbitrary parameter in current profiles since DNG 1.4.  Hey, the minute you buy into the idea that all a profile needs to do linearly is plop you into perceptual intent projection lines, the sky is the limit and Ken Rockwell is perceptually colorimetric.

Jack

My standard trick when I was younger was to go to the Kodak site and get the densitometric channel by channel data for their films; other types I got from old camera magazines, in the old days camera mags were really geeky. This allowed me to figure out their proprietary tints in the shadows and the highlight rolloffs. May not have been a scientific method for profile design, but it gave me profiles I could live with

I am happy people are debating this issue seriously here. It is time camera color improved, and it won't get better without debate, whatever the tool set.

Edmund

[Bart_van_der_Wolf]

That makes sense to keep the neutrals 'neutral'; I find the fact that it is possible to keep greys neutral all the way from the shadows to the highlights, whilst giving an overall warm look to images, interesting. I often find myself using the Color Balance wheels in C1 to compensate for the yellow cast; this helps to create a more neutral looking file overall in many cases but naturally means that the greys are no longer perfectly neutral 'by the numbers', and there are times when this causes more issues than it solves.

Anyway, I guess the colours out of C1 are what they are and it is unlikely that Phase is going to change its approach to colour rendering any time soon...

Hi,

I agree that correcting to achieve a different 'look' with the Colorbalance tools will change the neutral tones as well, so that's not the best method.

But Capture One is very capable of specifically modifying the (IMHO too yellow grass-greens) to less yellow, and even allows that to become the new default ICC profile to open new files with. The 'Advanced Color Editor' is our friend, so we are not stuck with how things are, we can change the (default) behavior.

Even if an image is mostly okay, but one wishes to change some tones, locally, that operation is hugely simplified by creating a Color Editor generated selection mask and use that on an adjustment layer. One can then locally modify the greens (or any other selection) by using a different Color Balance or with other tools, and e.g. even add some Structure to only those masked-in colors (e.g. to help foliage and grass definition).

Cheers,
Bart

[ErikKaffehr]

Hi Anders,

Here is an image I had some private conversations with Tim about.

http://echophoto.dnsalias.net/ekr/Articles/OLS_OnColor/BraheHus/

The raw files are here: http://echophoto.dnsalias.net/ekr/Articles/OLS_OnColor/BraheHus/index2.html

I have no grey card shots for those images, unfortunately.

http://echophoto.dnsalias.net/ekr/Articles/ColourCalibration/SLT99/

http://echophoto.dnsalias.net/ekr/Articles/ColourCalibration/P45+

http://echophoto.dnsalias.net/ekr/Articles/ColourCalibration/A7rII



I will try to put up more info.…

Best regards
Erik

I'm one of those that think Capture One's color is overrated, and I'm sure that's one reason some have chosen Hasselblad over Phase One despite the more primitive backs and software.

Phase One has this thing about putting a yellow cast over everything, and I just don't think that's the right thing to do. Hasselblad does put a little bit warmth in there, and in my own subjective profiles I do put a little warmth into yellows and greens, but to a much lesser extent and less global than Phase One's profiles.

I can't deny that the profiles are really well made in terms of technical design, but I personally don't agree with their choice on how to render colors.

It's hard to discuss colors without having images to show though. What's is a "huge" difference to one person can be "small" or even not detectable to another. I'd love to see image examples of the color issues Tim mentions, and try to figure out if it's a profile issue or a CFA issue.

[ErikKaffehr]

Hi Bart,

I played a little bit with the advanced colour editor in C1 and it seems to be very useful.

Best regards
Erik

Hi,

I agree that correcting to achieve a different 'look' with the Colorbalance tools will change the neutral tones as well, so that's not the best method.

But Capture One is very capable of specifically modifying the (IMHO too yellow grass-greens) to less yellow, and even allows that to become the new default ICC profile to open new files with. The 'Advanced Color Editor' is our friend, so we are not stuck with how things are, we can change the (default) behavior.

Even if an image is mostly okay, but one wishes to change some tones, locally, that operation is hugely simplified by creating a Color Editor generated selection mask and use that on an adjustment layer. One can then locally modify the greens (or any other selection) by using a different Color Balance or with other tools, and e.g. even add some Structure to only those masked-in colors (e.g. to help foliage and grass definition).

Cheers,
Bart

[ErikKaffehr]

Hi,

Here is another pair of images, shot on the P45+ and on the Sony A7rII, both processed in Lightroom using DCamProf profiles.
This page may give a better view and also has links to raw files: http://echophoto.dnsalias.net/ekr/Articles/Colours/GreenSeparation/

P45+	Sony A7rII

A few comments:

These two cameras not only represent CCD and CMOS, but also very different and somewhat problematic CFA designs. The P45+ has a CFA design favouring very saturated colours and the Sony CMOS has extended blue sensivity, all that according to Anders Torger who developed DCamProf.

Anders also says that the Pentax 645Z has similar issues to the but some other sensors (Phase One IQ3 100MP?) does not. It could be a different CFA or a different IR filter.

Vegetation has very high IR-content and digital camera sensors are quite sensitive to IR, so IR filtering clearly plays a role.

This time of the year, late sprint to early summer, we have a great variation of greens. In the samples above the tree in the backgrund had a very intense lush green.

What I see here is that rendition is quite similar, albeit the P45+ finds quite a bit more yellows in the greens. It may be that a program like RawTherapee would give even more similar rendition. I don't show RT samples, though, as I have found that I am prone to make mistakes in doing identical processing to images with RT.

We have seen in previous samples that Capture One adds quite a lot of yellow by default, so I left it out of this comparison.

My understanding is that most MFD sensors are more "main stream" now days. It would be very interesting to shoot with both DALSA and Kodak equipped sensors and compare with CMOS based cameras.

What I see is that a good profile maker can make two very different sensors quite similar and I would be not surprised if they could be even closer by adding some look.

Best regards
Erik

[alifatemi]

In my field shots using P45+ and Sony A7rII it may be differences that simple profiles cannot handle. It is possible to tweak profiles a lot, of course.

Erik, how can you tweet profile? Is it possible? When I profiling my cameras with Xrite profiler and compare the picture with passport, I like to fine tune the profile a little bit sometimes but don't know how. Thanks