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Bruce Jamieson
04-09-2007, 02:06 PM
I am handling the Photoshop work for a bunch of rendered images that my coworkers produce in Lightwave and every single image they give me has no color profile attached to it. Is there such thing as a Lightwave RGB profile?

Without a color profile, the renders are mystery meat. What's the white point? Gamma? Lab values for primaries? I can assign sRGB, Adobe RGB or any ol' RGB to the shot and each one can look radically different. I've generally used sRGB in the past when this issue has come up and have been fairly happy with the results, but I was wondering if LightWave has a particular RGB colorspace that would eliminate any question over the meaning of the image's color numbers.

Thanks,
Bruce

JeffrySG
04-09-2007, 02:24 PM
...are they (and you) running on Macs or PCs?

Bruce Jamieson
04-09-2007, 03:12 PM
I'm running a Mac, the images are rendered on Macs usually but sometimes are done on PCs. In either case, the rendered images have no icc profile attached to them, and this would be a problem in on either a Mac or PC.

JeffrySG
04-09-2007, 08:47 PM
What I've found typically on the Mac is that if the 3d software doesn't use any ICC profiles, the images are actually being rendered in whatever the Screen Color Space is. So for me even though they may not have an ICC, I would ASSIGN (not convert) them, in Photoshop, to my screen ICC space which is my DELL Calibrated Profile.

I'm not really sure if the same would apply to the images on a PC as I'm not really familiar with the way Windows handles Profiles.

One way to test this is to do a test render and leave the image open in LW. Then also open the image in PS and assign the screen ICC to that image. Move the windows so you can see both of them and they should look the same.

Give that a shot and see if it works!

Jeff

Giacomo99
04-10-2007, 07:06 AM
One way to test this is to do a test render and leave the image open in LW. Then also open the image in PS and assign the screen ICC to that image. Move the windows so you can see both of them and they should look the same.

Unless I'm missing something, I can't imagine why anyone would want to do what you're describing--what you're suggesting is, in effect, to de-calibrate Photoshop to the monitor settings so the image looks the same as in Lightwave.

The goal here, though, is to create and apply the profile *in Lightwave* so the image remains the same when viewed in Photoshop.

I've certainly spent a lot of time re-rendering images that suddenly became way too dark when viewed with Photoshop's superior color-management capabilities, and I also would appreciate any help in this area. As far as I know, there are NO color-calibration tools in Lightwave, and it's been a huge headache at times.

JeffrySG
04-10-2007, 07:19 AM
^What I was suggesting does not CHANGE the colors in the image... I simply applies the CORRECT color ICC profile to the image that does not have a ICC tag. Photoshop does not have any better knowledge of what color space an image is really in if there is not an ICC profile associated with that image. What you need to do is ASSIGN (not CONVERT) the CORRECT ICC profile to that image so the colors look accurate and true to the original intent.

What PS does to an image if there is not ICC profile is totally dependent on how you have your color space setting set in PS. This is VERY critical - as it can convert or assign different profiles with out your knowledge if you don't know what those settings are.

If there is a way to assign an ICC profile in LW that is always the best. ;)

Photoshop does not have superior color management viewing capabilities, it simply honors what profiles it finds and if it doesn't find any it will do what you have it set to do - which may be a bad thing if you don't understand what colorspace your untagged images are in.

Bruce Jamieson
04-10-2007, 12:24 PM
I've given a try to assigning (not converting) these renders to the monitor profile of the computer that rendered it. Though it may not be the final answer, it actually helped open up the shadows in the shot and calm down some strange coloration. Hadn't had the chance to compare the render to the Lightwave scene side by side yet, though.

If anyone does work with untagged renders and Photoshop, you can see what importance it is to have the right profile simply by selecting different RGB profiles in your color settings. As you go down the list of profiles you'll be shocked by what it does to your render, sometimes leaving you with truly horrible results.

I don't know a whole lot of the history of Lightwave, so maybe someone who does might be able to shed some light on this. Was Lightwave originally intended purely for video? In the US or Great Britain (NTSC or PAL)? If it originally was for still frames it might be geared toward sRGB which is kind of a PC standard. Just some guesses. I'm surprised that Lightwave doesn't have a color space, as if the RGB numbers it generates are kind of arbitrary and it's up to the user to determine what RGB colors mean to Lightwave.

-Bruce

Thomas M.
04-10-2007, 03:43 PM
Don't assign any monitor profiles. That's ridiculous. If you want to assign anything, then open the images with PS, let PS ask you what to do about the profile and choose Assign "GenericRGB" and convert to working RGB. Your working RGB should be sRGB, AdobeRGB or any other profile of your choice. Your monitor profile is of no importance to anybody else except your graphic card. Don't even think about selecting your monitor profile in any application as a profile.

JeffrySG
04-10-2007, 03:57 PM
^I agree. I would never use a monitor profile as a working profile in PS or use it in any application for a working profile - if anyone thought that is what I was saying, then they did not understand my explanation.

Bruce, I would do a little research on your own and see what you find. In my experience with rendering with Strata3d on a Mac and Photoshop, what I said is 100% accurate and true. You may find other info to be true with LW on the Mac and/or PC.

Feel free to PM me with any other questions! :)

cheers!
Jeff