Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: Joseph Holmes Ekta Space with Gamma L

  1. #1

    Join Date
    May 2018
    Posts
    32

    Joseph Holmes Ekta Space with Gamma L

    Dear photographers, as many of you i use for the scanned output an excellent color space Ekta Space PS 5 by Joseph Holmes. This space fine represent a color gamut of scanned transparencies.
    But with gamma 2.2 these images lacks details in shadows, and often have a steps in the tonal gradients. Joseph on his site offer a paid modified version of his space, called Chrome Space 100, with the same primaries and gamut, but modified tone curve, as he wrote, - "very carefully designed to match the tonality of perceptually linear printers". Here i do not have enough skills to design such a complicated curve, but i decided to simply replace the curve in the Ekta PS5 profile with the perceptually linear L* tonal curve. This takes desired effect with more smooth tonal gradients but more bright blacks. Here i want to ask dear photographers to test this colorspace especially against paid Chrome Space 100.

    Click image for larger version. 

Name:	06.07.2018_ 3.24.13_ 0010.jpg 
Views:	22 
Size:	25.3 KB 
ID:	180150

    A link to Holmes comparison
    https://www.josephholmes.com/profile...ail-comparison

    Get profile

  2. #2
    Peter De Smidt's Avatar
    Join Date
    Jan 2001
    Location
    Fond du Lac, WI, USA
    Posts
    8,954

    Re: Joseph Holmes Ekta Space with Gamma L

    I have Joseph’s spaces. I can compare them tomorrow.
    “You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
    ― Alexander Den Heijer, Nothing You Don't Already Know

  3. #3

    Join Date
    May 2018
    Posts
    32

    Re: Joseph Holmes Ekta Space with Gamma L

    Dear Peter, i will appreciate!

  4. #4
    Peter De Smidt's Avatar
    Join Date
    Jan 2001
    Location
    Fond du Lac, WI, USA
    Posts
    8,954

    Re: Joseph Holmes Ekta Space with Gamma L

    I took a file and converted to Ekta Space, the original, and then duplicated it. For the first one, I then assigned Chrome 100. It lightened everything. For the second one, I assigned your space. It darkened everything. So if the goal is to get more shadow separation, then you're moving in the wrong direction.
    “You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
    ― Alexander Den Heijer, Nothing You Don't Already Know

  5. #5

    Join Date
    May 2017
    Posts
    232

    Re: Joseph Holmes Ekta Space with Gamma L

    Quote Originally Posted by yeolde View Post
    Dear photographers, as many of you i use for the scanned output an excellent color space Ekta Space PS 5 by Joseph Holmes. This space fine represent a color gamut of scanned transparencies.
    But with gamma 2.2 these images lacks details in shadows, and often have a steps in the tonal gradients. Joseph on his site offer a paid modified version of his space, called Chrome Space 100, with the same primaries and gamut, but modified tone curve, as he wrote, - "very carefully designed to match the tonality of perceptually linear printers". Here i do not have enough skills to design such a complicated curve, but i decided to simply replace the curve in the Ekta PS5 profile with the perceptually linear L* tonal curve. This takes desired effect with more smooth tonal gradients but more bright blacks. Here i want to ask dear photographers to test this colorspace especially against paid Chrome Space 100.

    Click image for larger version. 

Name:	06.07.2018_ 3.24.13_ 0010.jpg 
Views:	22 
Size:	25.3 KB 
ID:	180150

    A link to Holmes comparison
    https://www.josephholmes.com/profile...ail-comparison

    Get profile
    Hi, what do hope to achieve that you could not achieve, with just 16 bit input, a modern floating point image editor, and profiling?

    His approach makes sense if you need to conserve space, but in 2018 is this really best practise?

  6. #6

    Join Date
    May 2018
    Posts
    32

    Re: Joseph Holmes Ekta Space with Gamma L

    Dear Peter, thank you for the experiment! Looks like Joseph space have curve really differs from L*

    Dear Ted, my goal is just to have a color space for editing, which, when being assigned, correctly represent slide look, instead of assigning a large spaces with unnatural colours

    Sent from my MI MAX 2 using Tapatalk

  7. #7

    Join Date
    May 2017
    Posts
    232

    Re: Joseph Holmes Ekta Space with Gamma L

    Quote Originally Posted by yeolde View Post
    Dear Ted, my goal is just to have a color space for editing, which, when being assigned, correctly represent slide look, instead of assigning a large spaces with unnatural colours
    Hence my post, there is nothing that Joseph is offering that can't be achieved with a more modern method. IMHO The stuff he is discussing is very complex, easily misunderstood and hence is easy to go down the wrong rabbit hole.

  8. #8

    Join Date
    May 2018
    Posts
    32

    Re: Joseph Holmes Ekta Space with Gamma L

    Yep, but what is the modern method?

    Sent from my MI MAX 2 using Tapatalk

  9. #9
    Peter De Smidt's Avatar
    Join Date
    Jan 2001
    Location
    Fond du Lac, WI, USA
    Posts
    8,954

    Re: Joseph Holmes Ekta Space with Gamma L

    Why not just buy it? It's not expensive. " 10) All eight Holmes Master Profiles only (DCam 1, DCam 2, DCam 3, DCam 4, DCam 5, Chrome Space 100, Ekta Space PS5, and Monochrome): $30
    You can use this 8 profile set to help you decide which full set(s) you may want or just to use by themselves. Please refer to the extensive information on these four pages: first second third fourth to help you choose what's best for you."

    Ted's right that the theory behind all of these is complex, but on the other hand, they're very easy to use. My serious work is with BW, though, and so I rarely use them.
    “You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
    ― Alexander Den Heijer, Nothing You Don't Already Know

  10. #10

    Join Date
    May 2018
    Posts
    32

    Re: Joseph Holmes Ekta Space with Gamma L

    Dear Peter, its not a money questions, im experimented with a profile editing to improve a look of slides and give a space for the editing.

    Sent from my MI MAX 2 using Tapatalk

Similar Threads

  1. Replies: 11
    Last Post: 20-Dec-2014, 04:57
  2. Convert Gamma 1.8 to 2.2
    By sanking in forum Digital Processing
    Replies: 2
    Last Post: 16-Aug-2011, 20:11
  3. Joseph Holmes Ekta Space P5
    By Kirk Gittings in forum Digital Processing
    Replies: 51
    Last Post: 17-Aug-2006, 18:08
  4. Joseph Holmes website revisited
    By Paul Schilliger in forum Announcements
    Replies: 10
    Last Post: 9-Mar-2004, 23:02
  5. Joseph Holmes website
    By Paul Schilliger in forum Business
    Replies: 4
    Last Post: 1-May-2002, 22:50

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •