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Posted: Fri Jan 19, 2007 7:56 am
by Tim Ellis
Hi matcad,
I ran an Auto colour & Auto levels with Photoshop, which strips out a lot of the yellow & red colour cast that's present. However that's more of a post process, rather than pre render.
I'm not sure if your material colours match the reference, which is adding to the colour cast.
Use Photoshop eye dropper, to take a couple of RGB readings from the photo, then use these as the basis for your MXM colours.
The incandescent lights will add to the yellow colour, try with a whiter emitter for those lights.
Did the flash go off when the photo was taken? A position matched flash plane would help if so.
The tiles don't need their colour map, or whatever is causing the darker areas, that's if you're going for an exact match. Just use the eye dropper RGB valus instead of the colour map, but retain the bump maps.
The mosaic tiling could do with more bump or a normal map.
Hope this helps,
Tim.
Posted: Fri Jan 19, 2007 8:51 am
by superbad
The problem is that digital cameras automatically set the white balance based on whatever lighting is present, so everything (usually) looks white, or close to it. Maxwell just takes it straight as is. You have a couple options- one is to just make the emitters white, and the other is to adjust the white balance after the fact in Photoshop. The former is usually easier.
Posted: Fri Jan 19, 2007 12:29 pm
by Mihai
Maxwells whitebalance is set at 6500K, so incandescent lights will look yellow. Just post process the image after the render.
Posted: Fri Jan 19, 2007 1:31 pm
by tom
I think your camera is applying auto white balance to the photo. Do you have a chance to turn the auto white balance off and fixing it at 6500K? I'm sure then the photo would come out yellowish, too

Or, as already suggested you can auto level your render in the post...
Posted: Fri Jan 19, 2007 2:50 pm
by tom
Yes, with the fixed balance (white point=6500K) it would surely come out more yellowish or orange.
matcad wrote:...we see in real life...
This is also auto-leveled in our brain. Preception is questionable...
Posted: Sun Jan 21, 2007 6:12 pm
by tom
1-In Photoshop open both the render and the reference photo.
2-Select the window of the rendered image.
3-From menu, select --> Image / Adjustments / Match Color...
4-Set the photo reference as source image and click OK.

Posted: Sun Jan 21, 2007 6:35 pm
by superbad
matcad wrote:I also boosted the monitor gamma to 3 in the Preview/MXI tab.
This is killing your contrast. You're generally better leaving gamma around 2 - 2.2, and adjusting the exposure if the scene is too dim.
As for color, I use Corel Photopaint, and it has an option to adjust white balance in degrees Kelvin- just slide it until it's right. I'm 99% sure Photoshop has the same thing.
Posted: Sun Jan 21, 2007 7:36 pm
by ricardo
Photoshop has 'image->adjust->photo filter' that mimics filters on lens, usually the cooling 82A(not sure) is the right choice for this kind of fixing.
Ricardo
EDIT: By the way, don't mess with gamma, it alters the way you see the image, but has no effect on data, so when you try to print it's all wrong...
Ricardo
Posted: Mon Jan 22, 2007 12:23 pm
by tom
I don't know what's different with the PSs we have, but this is what I have as a result of the method I've described above.
Very similar to photo ambiance, no?
Posted: Wed Jan 31, 2007 10:13 pm
by w i l l
ricardo wrote:
EDIT: By the way, don't mess with gamma, it alters the way you see the image, but has no effect on data, so when you try to print it's all wrong...
Ricardo
Is that right? What's the point in having this setting if it doesn't effect the data?
Posted: Fri Feb 02, 2007 7:32 am
by superbad
It definitely has an effect on my data.
Posted: Fri Feb 02, 2007 7:44 pm
by w i l l
Uh A-Team?
Posted: Sat Feb 03, 2007 2:48 am
by Mihai
By adjusting gamma, you are adjusting how that image is displayed on the monitor, for example to compensate the fact the Macs use a different gamma (1.8 ), then Windows (2.2). You can adjust the gamma so that it looks consistent across platforms, but ricardo is right, when you then print that image you might get completely unexpected results.
Posted: Sat Feb 03, 2007 2:55 am
by w i l l
oooooo shit.
Posted: Sat Feb 03, 2007 1:15 pm
by Tea_Bag
Question Bout the gamma,
My properties for my gamma on my desktop is 1.00? So does that mean that in the render window I need to change my gamma to 1.00? If I wack it up to 2.2 on my desktop its just to bright
