Export from Raw directly to an 8 Bit Jpeg

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stlbob

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I want to send files to a lab for printing. The lab requires JPEG files in SRGB color space and 8 bit files.

LR works great to export my files into JPEG in the SRGB Color Space but I cannot export in the 8 bit format.

This might be a good LR improvement.

The only fix I have found is to open the 16 bit JPEG into Photoshop and changing to 8 bits there which seems like an extra step that could be handled by LR.

Am I missing something or is there an easier way?
 
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Bob, by definition, standard JPG is an eight bit format; that's what Lr is exporting.

What makes you think the JPGs you're getting from Lr's export aren't 8 bit?
 
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That is a great point -- and great news!

OOOPS!

I opened the JPEG files in Photoshop and I thought it showed them as 16 bit.

Upon further testing -- you are absolutely right -- they are 8 bit!

How do I sheepishly withdraw my request a new LR feature??

Thanks for the correction -- this will really speed up my work!

Bob
 
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Brad, I hate to belabor this topic --

I exported a raw file from LR to obtain a 16 bit TIFF file upsized to 16 x 2' inches. I make final adjustments prior to printing on this file.

I then exported the TIFF to a full size JPEG in SRGB (with no re-sizing) to send to my lab for printing.

I then soft proof the JPEG file in PS CS4 using the lab printer profile. On my PS screen, PS reports on the tab at the top of the screen, the following:

file name.jpg (RGB/16*)

Also, if I click on Image/Mode both RGB and 16 Bits/Channel are check marked.

Does this mean I have a JPG file with 16 bits per channel?

My lab says I need to make the change to Image/Mode and check 8 Bits/Channel so that 16 Bits/Channel is not checked.

Appreciate your advice.

Bob
 
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Bob, I've had a look at this and can replicate your result. However to do this I have Camera Raw set to open jpegs in PS. Then the jpeg opens as 16bit IF you have that selected in the file options at the bottom of the ACR window. You can easily select 8bit. 16bit is an option as some may want to save as jpg2''' which takes 16bit I believe.
 
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[quote author=stlbob link=topic=7374.msg5'3'3#msg5'3'3 date=1248811255]
Does this mean I have a JPG file with 16 bits per channel?
[/quote]

No, a jpeg, by definition, is only 8 bits. When you come to save that 16-bit file, it won't let you save it as a jpeg - it'll force you to save as TIFF or similar format, or drop back to 8-bit again.

When you've opened that 8-bit jpeg using ACR set to 16-bit, you've literally put that 8-bit depth of data into a 16-bit amount of 'space' (that's not the techie word!). Imagine pouring half a pint of beer into full pint glass - you won't get any more beer by doing that.
 
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[quote author=Victoria Bampton link=topic=7374.msg5'424#msg5'424 date=12489'5492]
When you've opened that 8-bit jpeg using ACR set to 16-bit, you've literally put that 8-bit depth of data into a 16-bit amount of 'space' (that's not the techie word!). Imagine pouring half a pint of beer into full pint glass - you won't get any more beer by doing that.
[/quote] Actually, you start with a half pint and fill it up the rest of the way with water. (Kinda like Lite Beer). Once you have applied a filter your 8 bit colors get diluted into 16 bits of color. Like Lite beer, it is not as great as a stout ale, but it is better than nothing.
 
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