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jshurak · 12-20-2007, 06:20 AM

I developed this picture in Lightroom and everything looked great. Nice exposure, good colors. Then I sent it over to PS for sharpening. I changed it to lab mode, and sharpened the lightness channel.......after which I noticed that it looked a bit darker. I sharpened like this after reading it somewhere.....I wonder if this is the issue. Although the .dng and sharpened .tiff didn't look too different exposurewise. Here is the shot. I'm going to post the pre-exported to PS shot when I get home......

**jfdavis58** · 12-20-2007, 07:29 AM

How complicated should I make the answer?

In a nutshell:
All color spaces are not equal; every conversion from 'A' space to 'B' space has the potential for loss and/or shift. It's not an 'issue', it's the math.

Originally posted by jshurak

I developed this picture in Lightroom and everything looked great. Nice exposure, good colors. Then I sent it over to PS for sharpening. I changed it to lab mode, and sharpened the lightness channel.......after which I noticed that it looked a bit darker. I sharpened like this after reading it somewhere.....I wonder if this is the issue. Although the .dng and sharpened .tiff didn't look too different exposurewise. Here is the shot. I'm going to post the pre-exported to PS shot when I get home......

jshurak · 12-20-2007, 07:58 AM

so nothing is regained when converting back to RGB?

**jfdavis58** · 12-20-2007, 08:21 AM

Losses are permanent and cumulative with each conversion; shifts are, at best haphazard and unpredictable in those areas of greatest shift.

Originally posted by jshurak

so nothing is regained when converting back to RGB?

jshurak · 12-20-2007, 08:36 AM

well I know what I won't be doing again!

I'm still going to post the pre export to PS. It doesn't explain why the DNG would appear the same as the tiff after the sharpening.....could just be my eyes though.

12-20-2007, 06:20 AM	#1
jshurak Veteran Member Join Date: Jul 2007 Location: philadelphia Posts: 627	Lab Mode issues? I developed this picture in Lightroom and everything looked great. Nice exposure, good colors. Then I sent it over to PS for sharpening. I changed it to lab mode, and sharpened the lightness channel.......after which I noticed that it looked a bit darker. I sharpened like this after reading it somewhere.....I wonder if this is the issue. Although the .dng and sharpened .tiff didn't look too different exposurewise. Here is the shot. I'm going to post the pre-exported to PS shot when I get home......

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12-20-2007, 07:29 AM	#2
jfdavis58 Site Supporter Join Date: Nov 2006 Location: 13 S 0357397-3884316 Photos: Gallery Posts: 882	How complicated should I make the answer? In a nutshell: All color spaces are not equal; every conversion from 'A' space to 'B' space has the potential for loss and/or shift. It's not an 'issue', it's the math. Originally posted by jshurak I developed this picture in Lightroom and everything looked great. Nice exposure, good colors. Then I sent it over to PS for sharpening. I changed it to lab mode, and sharpened the lightness channel.......after which I noticed that it looked a bit darker. I sharpened like this after reading it somewhere.....I wonder if this is the issue. Although the .dng and sharpened .tiff didn't look too different exposurewise. Here is the shot. I'm going to post the pre-exported to PS shot when I get home......

12-20-2007, 07:58 AM	#3
jshurak Veteran Member Join Date: Jul 2007 Location: philadelphia Posts: 627 Original Poster	so nothing is regained when converting back to RGB?

12-20-2007, 08:21 AM	#4
jfdavis58 Site Supporter Join Date: Nov 2006 Location: 13 S 0357397-3884316 Photos: Gallery Posts: 882	Losses are permanent and cumulative with each conversion; shifts are, at best haphazard and unpredictable in those areas of greatest shift. Originally posted by jshurak so nothing is regained when converting back to RGB?

12-20-2007, 08:36 AM	#5
jshurak Veteran Member Join Date: Jul 2007 Location: philadelphia Posts: 627 Original Poster	well I know what I won't be doing again! I'm still going to post the pre export to PS. It doesn't explain why the DNG would appear the same as the tiff after the sharpening.....could just be my eyes though.

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Lab Mode issues?

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