Soft proofing ON or OFF?

[M.Chapman]

I've recently become more aware that the histogram shown by LR before exporting an image to an AdobeRGB jpg doesn't match that shown when I load the exported jpg into PS or any other editor. In particular the red channel may show clipping when viewing the exported jpg which isn't apparent when working with the RAW file in LR. This is presumably because the AdobeRGB is a smaller colour space than LR uses internally. Given that it's generally reckoned that images shouldn't have blown highlights (and colours?) when uploading Alamy, should I be using soft proofing in LR with profile set to AdobeRGB to check/adjust the histogram before exporting jpgs for Alamy?

 

 

[MDM]

The soft proofing clipping indicators show colours that cannot be displayed either in your monitor colour space or in the destination colour space, not blown highlights and shadows, so are mainly used if you are printing or sending an image away for professional printing where the lab has supplied a printer profile. So I would think you don't use soft proofing for images to be submitted for stock. However, it is very useful in demonstrating what you actually lose colour-wise if you start with a raw image and use AdobeRGB or sRGB as your destination space in the conversion. In particular, sRGB is a big loser.

 

The differences you are seeing in the histogram may be due to the 16-bit to 8-bit conversion which will occur when you convert to JPEG rather than the change in colour space. I don't think it is worth worrying about given that almost nobody who submits to Alamy will have even considered this. But of course one should always aim for the best one can I think so you may want to rework the 8-bit image in Photoshop before saving as JPEG rather than exporting as JPEG.

[M.Chapman]

9 hours ago, MDM said:

The soft proofing clipping indicators show colours that cannot be displayed either in your monitor colour space or in the destination colour space, not blown highlights and shadows, so are mainly used if you are printing or sending an image away for professional printing where the lab has supplied a printer profile. So I would think you don't use soft proofing for images to be submitted for stock. However, it is very useful in demonstrating what you actually lose colour-wise if you start with a raw image and use AdobeRGB or sRGB as your destination space in the conversion. In particular, sRGB is a big loser.

 

The differences you are seeing in the histogram may be due to the 16-bit to 8-bit conversion which will occur when you convert to JPEG rather than the change in colour space. I don't think it is worth worrying about given that almost nobody who submits to Alamy will have even considered this. But of course one should always aim for the best one can I think so you may want to rework the 8-bit image in Photoshop before saving as JPEG rather than exporting as JPEG.

 

I'm not so concerned about the indicators, it was more to do with the shape/clipping of the histogram. I'm pretty certain that is caused by changing colour space and has nothing to do with 8 and 16 bit mode. Here's what I tried. Open a RAW with strong reds in LR. In develop module I adjust exposure and/or white point to achieve full tonal range using histogram with no clipping on any channel. Export image to jpg with AdobeRGB profile, (ready to upload to Alamy, for example). Open jpg image in PS (to inspect it, not edit it). Histogram now shows clipping in the red channel. If I repeat the tests with sRGB the effect is even more significant (not really a surprise).

 

If I look at the soft proofed histogram in LR with profile set to aRGB or sRGB then the "soft proof" histogram in LR looks pretty similar to that I see when loading the aRGB or sRGB into PS. I suppose I'd naively thought the effect was so small I could ignore it. But for some images it seems quite significant and suggests (if avoiding clipping is a priority) that the histogram should be checked using soft proofing before exporting to aRGB jpg.

 

Of more interest (to me) I tried the same test using PS. I opened the RAW in PS, then in ACR adjusted the histogram, transferred to PS and then convert to aRGB and the histogram doesn't change (i.e. my adjustment still appears as I set it, max tonal range, no clipping). This is presumably because my working colour space in PS is already AdobeRGB. This seems good news to me because I only use ACR and PS and the histograms are then consistent. 

 

But, is it sensible to have my working space of aRGB in PS, bearing in mind my primary objective is to produce aRGB jpgs suitable for Alamy? It seems sensible to me, but am I missing something?

 

Mark

 

 

[MDM]

To the last question, I would say yes. That is what I do. Some advocate using ProPhoto as the working space as it is vast in comparison so you are throwing away data not using it. I used to but I got a wide gamut monitor which is supposed to show almost 100% AdobeRGB so I decided that it would be nice to be able to see the colours I am actually producing and went back to AdobeRGB. Also if you forget to change the colour space when creating a JPEG for online use, ProPhoto can give some very odd looking results on the web.

 

I'm sure you are right about changing colour space causing clipping of some colours if the lightness is close to clipping anyway. Looking at the histos, changing colour spacet certainly can have a strong effect but I'm only seeing clipping if it was already close anyway. Since Adobe introduced Process 2012, I think clipping of highlights is much less of an issue than it used to be ( for me in any case). I remember yellow used to run away in the highlights on Nikon D700 files but that is no longer the case. 

 

I don't check everything in soft proofing except when printing. Then I always make a proof copy which I use with the correct profile if printing myself. If sending to a lab, then I check the proof copy but I send a modified file based on the lab profile but with an embedded AdobeRGB profile. 

[M.Chapman]

1 hour ago, MDM said:

I used to but I got a wide gamut monitor which is supposed to show almost 100% AdobeRGB so I decided that it would be nice to be able to see the colours I am actually producing and went back to AdobeRGB. Also if you forget to change the colour space when creating a JPEG for online use, ProPhoto can give some very odd looking results on the web.

 

I can set my default workspace to AdobeRGB in PS, but I don't think this is possible in LR? The excerpt (in italics) below is from Adobe's website  https://helpx.adobe.com/uk/lightroom/help/color-management.html . Note the last paragraph. It would be nice if the develop module default colour space could be set to AdobeRGB (just like it can in PS), or have you found a way to do this?

 

How Lightroom Classic CC manages color

 

Lightroom Classic CC primarily uses the Adobe RGB color space to display colors. The Adobe RGB gamut includes most of the colors that digital cameras can capture as well as some printable colors (cyans and blues, in particular) that can’t be defined using the smaller, web-friendly sRGB color space.

 

Lightroom Classic CC uses Adobe RGB: for

• previews in the Library, Map, Book, Slideshow, Print, and Web modules
• when printing in Draft mode
• in exported PDF slideshows and uploaded web galleries when you send a book to Blurb.com (If you export books as PDF or JPEG from the Book module, however, you can choose sRGB or a different color profile.)
• for photos uploaded to Facebook and other photo-sharing sites using the Publish Services panel

In the Develop module, by default Lightroom Classic CC displays previews using the ProPhoto RGB color space. ProPhoto RGB contains all of the colors that digital cameras can capture, making it an excellent choice for editing images. In the Develop module, you can also use the Soft Proofing panel to preview how color looks under various color-managed printing conditions. 

 

Mark

[MDM]

That is all correct. The Develop Module in Lightroom colour space can't be changed to keep things simple I believe as the colour settings dialog in Photoshop has caused so much confusion over the years. If you want the background on this, check out Jeff Schewe's books:  Digital Negative and Digital Print. That is where I got most of my info as well as Martin Evening's Lightroom books.

[M.Chapman]

OK Thanks.

 

Mark

[giphotostock]

On 8/15/2018 at 00:01, M.Chapman said:

I've recently become more aware that the histogram shown by LR before exporting an image to an AdobeRGB jpg doesn't match that shown when I load the exported jpg into PS or any other editor. In particular the red channel may show clipping when viewing the exported jpg which isn't apparent when working with the RAW file in LR. This is presumably because the AdobeRGB is a smaller colour space than LR uses internally. Given that it's generally reckoned that images shouldn't have blown highlights (and colours?) when uploading Alamy, should I be using soft proofing in LR with profile set to AdobeRGB to check/adjust the histogram before exporting jpgs for Alamy?

 

 

Go for it. After I discovered the S button press in the Develop module, it saved me enormous amounts of time when trying to avoid clipping of those pesky saturated colors.

GI