Joseph Holmes workspace examples

Thanks Eric for clarifying/confirming this.

I'm really not obsessed by the number of conversions. I was merely pointing out that it looks as if the Bibble/Holmes workflow means an extra step/conversion compared to for example LightZone that converts directly from its internal image processing space into Holmes. In reality the number of steps/conversions is exactly the same. It's just that the working space (image processing space) in Bibble is variable and fixed in LightZone.

Herman

One other issue about the use of J. Holmes' profiles related to working spaces was bothering me. I wrote this e-mail to Joseph:

I'm currently using your Chrome 100, Dcam 4, aRGB/ppRGB variant sets.

On your website you explain the reason for the specific 1024-point TRC
that is included in your commercial profiles (match with perceptually
linear printers).

I was wondering how your proprietary TRC impacts image editing? Put
differently, if one works with your profiles, how important is it to EDIT
images in one of your J. Holmes working spaces?

Take for example a raw converter like Bibble. Bibble does not (yet) allow
for custom working spaces. In order to get an image into one of your
commercial profiles, I have to use ProPhoto RGB as an intermediate working
space in Bibble and then convert to Chrome 100, Dcam x etc. (in Bibble,
Photoshop whatever).

Now, raw converters like Bibble have evolved from pure converters to
"photo editors". As described above, in Bibble I have to use ProPhoto RGB
as a working space. I suspect that image editing in Bibble (necessarily
based on ProPhoto RGB) should be avoided, as this image processing in done
on basis of ProPhoto RGB instead of one of your commercial
profiles/spaces.

Another example, LightZone brings raw files into its own linear gamma
wide gamut space. Besides a raw converter, LightZone is also a very nice
Photo Editor, but image editing is done in LightZone's internal processing
space instead of one of your profiles.

Thanks in advance for your help.

Joseph's reply:

Hello Herman,

I don't think the tone curve differences between the various RGB
spaces has much of an impact on the results obtained from the various
editing tools. There certainly is an impact, but the main reason for
my optimized tone curve is to minimize the quantization error when
converting 24-bit files to printer space at the end of the editing
process. I do think that the RGB tools are apt to work nicely when
files are in RGB spaces with tone curves that are like mine, relative
to gamma curves. But I'd not claim a substantial advantage in that
regard.

Don't worry about editing in ProPhoto. Just keep the data in 48-bit
(it naturally is inside raw converters).

I have never investigated this question as I've not thought it much
of an issue, but I should, especially now that Adobe is using gamma
1.0 for LightRoom. I need a more deeply informed opinion on this
issue.

Have a good evening,

Joe Holmes

thank you Herman, both for asking the question and sharing the answer. sounds like you struck a chord with him as well