Colour space

[M.Chapman]

1 hour ago, Harry Harrison said:

 

Excellent, a long thread and a lot of work for you, but worth it.

 

I don't want to sound churlish but if they'd posted that statement publicly to all contributors when they joined up none of this would have been necessary. Commercially sensitive? Surely not.

 

Or at least corrected the early posting in this thread where Alamy are quoted as saying. "This is totally up to you and your own workflow, but we work with Adobe RGB and ignore any embedded ICC profiles when we process your images so before sending we recommend saving all images as Adobe RGB (1998)."

 

That would have saved me buying two of my own images to check what was going on. I did at least get the commission though. 🙂

 

Mark

Edited July 16, 2019 by M.Chapman

[MDM]

16 hours ago, M.Chapman said:

I sought further clarification from Alamy as to whether the conversion from sRGB occurs when they receive our images, or only when they are supplied for download or display. I also asked why the profiles are stripped. This is the reply I have received.

 

We convert on submission, we don’t store any aRGB profiles. We’ve always worked in this way and there has been no customer demand for an aRGB file. In the past, it may have been preferable to process using aRGB but in reality, as a contributor it’s down to your preference. The images will be displayed on Alamy as sRGB.

 

We provide the images to the end user with the profile stripped because this is the most compatible and efficient way to do so. Software that supports colour profiles will assume that images without an embedded profile are in the sRGB profile. Software that doesn't support colour profiles will use monitor's profile, which is most likely to be sRGB as well in most cases.

 

I queried this reply, as I felt sure that when I first joined Alamy (in 2010) Alamy asked for AdobeRGB format submissions and the SizeChecker application (NB. not an Alamy application) also gives a profile warning if the profile isn't AdobeRGB. I've just had a phonecall from James Allsworth at Alamy who confirmed that the answer in blue above is correct and has been at least since 2005 when he joined Alamy. 

 

So there's the definitive answer which James said he was happy for me to post here. (Thanks James)

 

Mark

 

They certainly used to ask for Adobe RGB when I joined in 2009 - why is not clear if they have always been stripping the profile. It doesn't surprise me though. I guess they want a standardised approach across the board for all clients as it would no doubt be a sales nightmare to track and provide images with different profiles and for the vast majority of stock sales it doesn't matter, moreover because many photograpers are not using a colour-managed workflow in the first place. Clients who require really accurate colour will probably be commissioning images rather than licensing stock. 

 

I won't be changing my Adobe RGB workflow though as it is a trivial matter in Lightroom or Photoshop to export or save images with a different profile and there are  real differences when printing in terms of colour rendering - that includes home printing. 

 

 

[M.Chapman]

 

Yes, I'm sure they asked for aRGB when I joined in 2010. So something doesn't quite add up, especially given their fairly recent comment "This is totally up to you and your own workflow, but we work with Adobe RGB and ignore any embedded ICC profiles when we process your images so before sending we recommend saving all images as Adobe RGB (1998)."

 

Anyway the evidence is there, the images Alamy supply now are definitely sRGB with no profile and we have conformation from James Allsworth (Head of content).

 

22 minutes ago, MDM said:

there are  real differences when printing in terms of colour rendering - that includes home printing. 

 

That's interesting. I wonder how I can test the effect it has on my home setup? A side by side comparison of 2 separate prints never really works for me, unless perhaps I chopped them up, but even then the joins get in the way. I wonder if I set PS to aRGB workspace and then create an image with a decent colour range from RAW. Then save a copy as sRGB, then reimport it as a new layer over the top of the original aRGB and then erase strips or areas in the sRGB top layer to reveal the aRGB underneath and then print it out to give a perfect integrated comparison. Would that work? I suppose the sRGB will be converted back to aRGB when I import as a new layer above an aRGB original, but the process of converting to sRGB, saving and then converting back to aRGB on import should cause loss of colour info.

 

Mark

Edited July 17, 2019 by M.Chapman

[MDM]

35 minutes ago, M.Chapman said:

 

Yes, I'm sure they asked for aRGB when I joined in 2010. So something doesn't quite add up, especially given their fairly recent comment "This is totally up to you and your own workflow, but we work with Adobe RGB and ignore any embedded ICC profiles when we process your images so before sending we recommend saving all images as Adobe RGB (1998)."

 

Anyway the evidence is there, the images Alamy supply now are definitely sRGB with no profile and we have conformation from James Allsworth (Head of content).

 

 

That's interesting. I wonder how I can test the effect it has on my home setup? A side by side comparison of 2 separate prints never really works for me, unless perhaps I chopped them up, but even then the joins get in the way. I wonder if I set PS to aRGB workspace and then create an image with a decent colour range from RAW. Then save a copy as sRGB, then reimport it as a new layer over the top of the original aRGB and then erase strips or areas in the sRGB top layer to reveal the aRGB underneath and then print it out to give a perfect integrated comparison. Would that work? I suppose the sRGB will be converted back to aRGB when I import as a new layer above an aRGB original, but the process of converting to sRGB, saving and then converting back to aRGB on import should cause loss of colour info.

 

Mark

 

 

If you use the soft-proofing facility in Lightroom, you will see that there are very distinct differences in the out-of-gamut colours for Adobe RGB versus sRGB. I guess it is more about what you can't see than what you can see with soft-proofing. I agree it can be difficult to judge by eye and you would probably need a colourimeter to really check things out properly in print.I've spent most of the last hour trying to devise an interesting experiment that would demonstrate the differences clearly in print but haven't managed to come up with anything defintive and need to get moving on my day but it is really interesting. Will definitely return to this when I have a bit of time.

[Allan Bell]

 

And I am sure, as stated in an earlier post, that when I joined in 2008 I was asked to submit images as aRGB too.

 

Allan

 

[Alamy]

Just to clear this up, we may have recommended that Adobe RGB was a preferred workspace for processing back in the day for various reasons including processing compatibility, but it's never been a QC requirement. Some of our standard responses still included that reference and we've now updated them for clarity.

 

There is no conspiracy to uncover - just process your images in whatever works best for you then when you upload we will:

• Convert to sRGB
• Display in sRGB on the website
• When ordered by a customer, provide a file without a colour profile for compatibility reasons

We won't keep an Adobe RGB version of your file if you do send one. We have no recorded cases of a client asking for one, but if they did, we would contact you directly to see if there is one available.

 

Cheers

 

James A

[DJ Myford]

There was no 'may' or 'preferred' about it: the requirement was aRGB. Just as we were told not to sharpen, and turn in-camera sharpening OFF. Then the stance changed to "don't over-sharpen". Or did it? Did we ever get an official reply on that, or a definition of 'over-sharpen'? Were files that were submitted unsharpened subsequently sharpened to allow them to compete?

Communicating with its contributors has never been Alamy's strong point, and this thread has demonstrated that. If I hadn't read it, I would still be under the impression that aRGB was required. To paraphrase a certain sci-fi character, Alamy is starting to damage my calm.

[wiskerke]

41 minutes ago, Alamy said:

When ordered by a customer, provide a file without a colour profile for compatibility reasons

 

Profiles are there for compatibility.

Think of it as cutting off your power plug from your coffee machine to plug it in with just the copper wire. It will function as long as you're in the UK and the coffee machine is from the UK too. But don't try it with your US device in the UK.

It's also a quality thing: your UK device will sometimes work in the US, but your coffee will be bleak.

 

43 minutes ago, Alamy said:

We have no recorded cases of a client asking for one, but if they did, we would contact you directly to see if there is one available.

 

Maybe if you would tell clients that they could ask for it?

Maybe even with a check box, like click here if you would rather have an Adobe RGB file (- this may delay the delivery).

Or a pick list:

profile: - none (sRGB)

             - sRGB with profile

             - AdobeRGB with profile (- this may delay the delivery)

 

Maybe just put a question in the next customer satisfaction survey. You may well be right for the clients you have. OTOH maybe there still are clients out there...

 

wim

[M.Chapman]

On 17/07/2019 at 15:39, Allan Bell said:

 

And I am sure, as stated in an earlier post, that when I joined in 2008 I was asked to submit images as aRGB too.

 

Allan

 

 

Wayback machine shows the following Alamy submission guidelines for contributors in 2008 here

https://web.archive.org/web/20081222011649/http://www.alamy.com:80/contributors/stock-photography-technical-criteria.asp

1. RGB files

   The issue of colour management for digital images is complex. To simplify things, Alamy asks contributors to submit images in RGB format. This is because the CMYK format has a smaller colour space, and so contains fewer colours. Unless you have reason to do otherwise, set your RGB "Color Settings" to "Adobe RGB (1998)" on both a Macintosh and a PC - this has become the defacto standard for most imaging professionals.

By 2010 that advice changed and no longer appears to mention aRGB, for example see here

https://web.archive.org/web/20101119110707/http://alamy.com/contributor/help/prepare-images.asp

 

I couldn't spot any web-pages that stated contributors must use aRGB or that it was a QC requirement. However it's possible different advice was floating around on the forum or in emails at that time. Certainly I gained the impression when I joined Alamy that aRGB was required. So that's what I was submitting until recently.

 

Personally I think it's a mistake to ship images without a profile. Although many systems will assume sRGB if there's no profile, Photoshop may not.  If PS is set to use aRGB working space it will (depending on the colour preference settings) open sRGB images with missing profiles as if they are aRGB with no warning message. The customer then gets an incorrectly rendered (more saturated) image. It gets even worse if the customer is using ProPhotoRGB working space.

 

Anyway it's good that current situation is now clear - thanks James. Please let us know if Alamy change their workflow.

 

Mark

Edited July 19, 2019 by M.Chapman

[M.Chapman]

On 17/07/2019 at 09:28, MDM said:

 

 

If you use the soft-proofing facility in Lightroom, you will see that there are very distinct differences in the out-of-gamut colours for Adobe RGB versus sRGB. I guess it is more about what you can't see than what you can see with soft-proofing. I agree it can be difficult to judge by eye and you would probably need a colourimeter to really check things out properly in print.I've spent most of the last hour trying to devise an interesting experiment that would demonstrate the differences clearly in print but haven't managed to come up with anything definitive and need to get moving on my day but it is really interesting. Will definitely return to this when I have a bit of time.

 

I've also been looking at doing some tests. I tried comparing sRGB versus aRGB versions of one of my Passport colour checker images on my monitor and printed out. I could see subtle differences on my monitor (calibrated HP23xi), but not in my printouts... (I've only got a Canon IP4200 with 5 inks CMY, Black and PhotoBlack).

 

I thought I'd try a more severe test by creating a Granger Chart (takes 30sec in PS) which contains a very wide gamut. This has been much more illuminating and reveals there's so much mis-information out there. Many of the tests people describe are flawed and simply show what happens when you apply an aRGB or ProPhotoRGB profile to an image without converting the image data first. The differences between correctly rendered sRGB, aRGB and ProPhotoRGB are relatively small. But many tests take sRGB data and (incorrectly) render it as aRGB or ProPhotoRGB and then say "Wow - look at how much more colourful the results are" and therefore assume the differences are much more significant. It also needs to be remembered that soft proofing is just a "simulation" so may not represent actual results.

 

I've just sent an email challenging one of the "expert's" comparison test results. If he comes back and confirms my observations I'll post some correctly produced Passport Colour Checker and Granger chart files saved as sRGB, aRGB and ProPhotoRGB image files so folks can draw their own conclusions on their hardware..

 

Mark

Edited July 19, 2019 by M.Chapman

[wiskerke]

The main problem is when you're converting to CMYK: e.g. sRGB files can have duller skies.

 

As for when people are assigning the wrong profile: that's just a mistake that cannot be avoided by the maker.

Assuming he/she was not stupid enough to send the client a file without a profile. Not something a professional photographer will do unless the client specifically asks for it.

And yes clients can and still do make mistakes. Usually not because they're stupid, but because they have their software set up incorrectly.

 

wim (sorry about the double negatives)

[M.Chapman]

On 19/07/2019 at 10:53, M.Chapman said:

I'll post some correctly produced Passport Colour Checker and Granger chart files saved as sRGB, aRGB and ProPhotoRGB image files so folks can draw their own conclusions on their hardware..

 

As part of my investigation (which ended with Alamy confirming they convert all images to sRGB and shipping without profiles) I produced some test images in each colour space and developed an analogy to help me understand the differences between colour profiles, profile assignment and profile conversion. I ended up writing it up as an article which is available here. https://hubpages.com/art/SRGB-AdobeRGB-and-ProPhotoRGB-colour-spaces . The article has links to the test images.

 

I hope you find it useful. Any comments (positive or negative) welcome. I'm happy to amend if I've got anything wrong. 

 

Mark