Downsides of using Camera Profile (.DCP) for "wrong" camera

[Alpacalypse (Uli)]

Hi everyone,

Here’s the situation:
I’m shooting with a Sony A7ii and something has been bugging me about the colors I get in RT. Everything always seemed a little too yellow/greenish. I usually fixed it by lowering the yellows in the (L*ab) b curve like this:

…but obviously I was never really satisfied with this solution.

Now, I stumbled upon the DCPs @Andy_Astbury1 kindly provided for non LR-Users and I was hopeful to get a nice starting point with those.

Unfortunately those are even worse than camera specific profile I’ve always used within RT! It’s a ridiculous yellow mess!

I’ve tried some other Sony profiles and interestingly enough, the A7iv profiles seem to work A LOT better. At least in my eyes.

Now, finally, here are my questions:

• Can someone who’s shotting with an A7ii confirm that those profiles are rubbish? Am I seeing things? Are all my monitors (I used 4 different ones) rubbish?
• Is there a downside of using A7iv profiles for my A7ii images?
• Any other solutions? Anyone know about some DCPs I can check out?

Thanks!

If it helps I can look for some image for a playraw, but I’m hesitant to post images that contain skin tones (which this is mostly about) for privacy reasons.

Here’s an example, neutral user profile, only minor adjustments with 3 different DCPs:

RT ‘camera specific profile’

A7m2 Portrait DCP

A7m4 PT DCP

[Andy_Astbury1 (Andy Astbury)]

Can you supply an example raw file as I have no ARWs ?

[Alpacalypse (Uli)]

Hi Andy,

I was just looking for something that I can provide. I think this one should be fine…

DSC06011.ARW (23.8 MB)

I will look for some more…

EDIT:
another one:
DSC04917.ARW (24.1 MB)

[Andy_Astbury1 (Andy Astbury)]

Hi Uli

DSC06011.ARW.pp3 (13.5 KB)

Two screen grabs to show how I’ve set up the colour panel and Lab under the exposure tab.

Skin tone on the lady on the left looks a little “sallow”, but the one on the right doesn’t look too far off.

An RGBGrey balance of 4928 is what’s giving those neutral blacks in the dress.

Your camera WB for this shot is 7298, hence it too looks yellowish when opened with no adjustments.

Don’t know what you think of the colour balance in these screen grabs - I don’t think it’s too bad.

[Alpacalypse (Uli)]

Thanks, Andy.

Maybe it’s just a matter of preference but for my taste the A7ii one (of my screengrabs) is way too yellowish. I’ve used the “portrait” DCP though, you think I should generally go for the neutral one?

[Thanatomanic (Roel)]

Hi @Alpacalypse. The majority of DCP profiles that are supplied with RT are based on good quality calibration shots taken for two illuminants. However, in the case for the A7ii profile, there may have been some manual fiddling going on, as per the description here: Updated dual-illuminant SONY ILCE-7M2 DCP · Beep6581/RawTherapee@34cf39f · GitHub
Then again, this commit has been superseded with another Updated SONY ILCE-7M2 dual-illuminant DCP · Beep6581/RawTherapee@f900d60 · GitHub that doesn’t really tell me anything on what has changed. So perhaps it’s not as ideal as you might expect…

@Alpacalypse

Is there a downside of using A7iv profiles for my A7ii images?

YMMV. Usually sensor responses are different, so the profiles are different. But then again, if it looks all right, it works all right.

@Alpacalypse

Any other solutions? Anyone know about some DCPs I can check out?

If you want a good calibration, the best option is always to get a color chart and do it yourself. Only use stuff for which you know how the profile was made.

Edit: just to be clear, DCP profiles can be used for all kinds of creative stuff. For the RT provided profiles the philosophy is to provide a as-close-as-possible-true-to-nature color calibration.

[Andy_Astbury1 (Andy Astbury)]

@Alpacalypse

I’ve used the “portrait” DCP though, you think I should generally go for the neutral one?

I’ll invariably choose Neutral, though occasionally I’ll try a Standard.

Portrait profiles can warm things up, Landscape profiles can cool things down, but they will all have different tone curves.

You will still have to custom white balance, whatever cam profile you use, as input profiles don’t override recorded WB, as far as I know.

[apostel338 (HP)]

Have you activated the look table in the camera specific profile? It seems to be off by default and takes away some of the yellowish in the samples I’ve looked at.

[Alpacalypse (Uli)]

Thanks, Roel. After some experimening I’ve found that the A7iv profiles give me skin tones that I prefer but histogram seems to be stretched a little more stretched.

I guess you’re right, and I need to get a myself a color chart… well, not now, but some day…

[Alpacalypse (Uli)]

Yeah, I still do the white balancing manually.

I guess I’ll keep experimenting for a bit…

@apostel338

Have you activated the look table in the camera specific profile? It seems to be off by default and takes away some of the yellowish in the samples I’ve looked at.

Yes, I’ve checked all four boxes for my tests. You’re right, for the “camera specific profile” it takes away some of the yellow whereas for the A7 profiles it adds yellow (but unchecked it looks even worse).

[nosle]

@apostel338

Have you activated the look table in the camera specific profile?

Just a warning that sometimes those look tables are quite the look… For my cameras (different brand) those look tables in auto matched profiles are mostly unusable. I don’t know how those look profiles are made or who has decided what look should be included but it seems it’s completely up to whoever made the profile. Anyone knowing better please please tell me off.

If you like the results it’s probably fine but I’m not sure the quality can be fully trusted.