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LAB color space equivalent in AE?
Hi
Can someone tell me if there is a LAB color space equivalent in AE? I’d like to try applying filter effects and curves to the luminance value of a layer, and not the colors.Local is the new global
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18 Replies
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you can probably get similar results by duplicating the layer, setting the top duplicate’s blending mode to ‘color’, then do the effects on the lower duplicate.
if you are working in 8-bpc, then you can do this with a single layer, using cc composite as the last effect and setting composite original to ‘color’.
Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW -
channel combiner1 set RGB to YUV
Effects
Channel combiner2 set YUV to RGBCurves Effects
RGB= don’t use
Red= lightness
Green=a
Blue=bThe God Of Color Of The Universe Will Rise Again!
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cc composite CS5 has a bug… Color blending and Luminosity blending are flipped
The God Of Color Of The Universe Will Rise Again!
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Thanks!
Now if only channel combiner were 16bit:(HDR Compander I suppose if I’m using a 16 or 32bit workflow.
Haven’t done a lot of testing with HDR Compander…for 8 bit effects in a 16-32bit project. What are the drawbacks?
Local is the new global
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With compression and uncompression you can lose some precision in values that you can’t see 95% of the time.
Maybe you want to start another thread!The God Of Color Of The Universe Will Rise Again!
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[jim bachalo] “Haven’t done a lot of testing with HDR Compander…for 8 bit effects in a 16-32bit project. What are the drawbacks?”
It is not a good option if you have a huge range of values. You have to use the Compander to compress ALL of the color information (that you want to keep) into an 8bpc range (0-1) and then expand that color information back out to its original range. This is problematic when you perform an operation in between the compression and the expansion that changes the bit depth.
So if you have values ranging from 0-50 the process of compressing those down to 0-1 is not inherently bad in 32bpc, but once you apply an 8bpc effect you have limited each color channel to only 256 unique values. When you expand that back out to 32bpc it will have superwhites, but it will show the worst banding you’ve ever seen in your life because it’s taking only 256 unique values and expanding them out to cover a range of values 50 times as large as 0-1.
All of that said, it’s a very valuable effect if you’re dealing with smaller ranges of values (0-5) or you don’t mind clipping the values at some superwhite level. Also it will be happier with 16bpc effects as you’ll be limiting to 65536 unique values instead of 256.
Darby Edelen
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[rona gales] ” cc composite CS5 has a bug… Color blending and Luminosity blending are flipped”
Weird, I don’t see this problem on my system.
Darby Edelen
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[jim bachalo] “Now if only channel combiner were 16bit:(“
Which is why I always use blend modes for this 🙂 The Luminosity or Color mode is perfect for your purposes. You’ll have access to the luminance and colors separately that way.
The only downside is that you don’t have access to the color difference channels (you’d have to use the Channel Combiner to do that), but there are very few reasons I can think of that any non-super-human-techno-graphics-compositor would ever need access to color difference channels.
Darby Edelen
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You’re probably not using HDR Compander the right way!
Also you’re not understanding the need and use of LAB/YUV color mode properly.The God Of Color Of The Universe Will Rise Again!
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[rona gales] “You’re probably not using HDR Compander the right way!
Also you’re not understanding the need and use of LAB/YUV color mode properly.”Make a Ramp, then use Exposure +5 stops and 0.5 gamma, add your HDR Compander effects, wedge your round trip Channel Combiner between them and find your best settings (Gain 5, Gamma 2).
I guarantee your ramp is going to look terrible on the other end of the HDR Compander effects with an 8bpc effect wedged between them.
Thanks for trying to fix my workflow though.
As for the need and use of Lab and YUV, in the original poster’s case they are entirely unnecessary. There is no need nor use for them in his scenario as he’s described it.
If you like to use curves to adjust the color difference components in YUV that’s fine, but that’s not what the original poster asked about and it’s not the ideal usage for what he wants to do.
If you’re disagreeing with something specific I said, please do tell me why you disagree.
Darby Edelen
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