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Thomas Boysen
08-01-2010, 11:42 AM
I am looking for advice on how to avoid overdoing the yellows in LR. The histogramme shows no blowing out whatsoever and I have a hard time assessing visually whether they are or not. But when I open the finished pic in Brezzebrowser, it looks aweful. Is there a setting that I am missing that makes LR more "sensitive" to individual colours being blown out? I prefer to do almost all my editing in LR and only really tough stuff in PS but if I can't resolve this all yellows bird will end up in PS, which would be a pain.
Thanks for any ideas

Thomas

Axel Hildebrandt
08-01-2010, 12:50 PM
Do the overexposed yellows show up before or after jpg conversion? Do you use ACR and then PS and what role does Breeze Browser play in your work-flow?

Thomas Boysen
08-01-2010, 01:00 PM
I shoot in raw and use Breezebrowser only to look at pics. My workflow is normally only LR3. When I take a pic with strong but according to LR3 not overblown yellows into PS as a tif file it shows up as overblown. If I just convert to jpg and look at it in Breezebrowser the overblown yellows are apparent. I know how to deal with the overblown yellows once I am in PS but I don't like working in LR thinking everything is ok and then having to redo files because LR3 doesn't show me what is going on.
hope this clarifies my problem, thanks for answering, Axel

Thomas

Axel Hildebrandt
08-01-2010, 01:10 PM
Do you save the TIFF as 16 bit Adobe RGB and is there a change of color space between RAW and TIFF file?

Thomas Boysen
08-01-2010, 01:20 PM
I save it as 16 bit adobe RGB but I am not sure about the colour space of the raw file. Is there one? I thought that just comes up after conversion. The camera is also set to adobe RGB b ut as I said my understanding is that this has no effect on raw pics.

Axel Hildebrandt
08-01-2010, 01:24 PM
I was wondering if you convert the RAW file to a color space with a different color gamut. If not, then I would expect that the histogram in ACR and PS should not differ much. You only see this in the yellow channel, not red?

Thomas Boysen
08-01-2010, 01:29 PM
I should add that I when converting to jpg I convert them to sRGB since I mainly view the pics on screen and rarely print.

Axel Hildebrandt
08-01-2010, 01:32 PM
I should add that I when converting to jpg I convert them to sRGB since I mainly view the pics on screen and rarely print.

This is usually when you can see problems in the red and yellow channel. I've never noticed it when converting RAW to TIFF.

Alfred Forns
08-01-2010, 08:12 PM
Hi Thomas Good thread !! Glad you mentioned the conversion to jpeg !! Best to convert to TIFF since you will still be working in 16 bit for any PS work and a good way to save your master file !!

Roger Clark
08-01-2010, 09:46 PM
Thomas,

Several things here.

Whenever one displays a histogram, select the color mode so the red, green and blue channels are independently displayed. That way one can see if one channel is clipped. I do this on camera too. If your software does not do this, I suggest using different software. Light meters in most cameras do not seem to expose strong colors well. For example, the blue channel is often overexposed on blue skies. Red and yellow flowers often have the red channel clipped. If you have the histogram for all 3 colors displayed on the camera, one can usually diagnose the problem at the time of capture and fix it. Same with processing.

Raw does not have a color space. Color space is set at the time of conversion.

If you convert to a broad gamut, like adobe RGB, then convert to sRGB, the smaller gamut can saturate some colors and clip the shadows too.

If you want to do 16 bit and space is a concern, consider jpeg 2000. Jpeg 200 will do 16-bit and lossless compression. Note, however, 16-bit data does not generally compress well.
Fortunately disk space is very low cost and getting lower by the day. Photoshop does not ship with jpeg 2000, but adobe provides the addition at no extra cost.

Roger

Thomas Boysen
08-02-2010, 10:53 AM
Thanks to all for the replies. I will have to be more aware of strong colours during capture and in processing and experiment a bit with my workflow.

Cheers

Thomas