Smart Sharpen 16 bit vs 8 bit

<p>I have an action which creates a smart filter layer and then applies a Smart Sharpen filter to the layer. I notice a significant speed increase in performing the action in 8 bit. 16 bit is much slower. What sort of quality penalty, if any would I be incurring by performing this action in 8 bit.<br>

thanks,<br>

pat</p>

<p>none, sharpening should be done at the end of post processing, after all color adjustments, and resizing for final output. As you always should convert to 8bit before printing, i would do that before sharpening also.</p>

>>> none, sharpening should be done at the end of post processing, after all color adjustments, and resizing for final

output.

 

No, sharpening is done at several stages of processing; at input, during editing selectively, and at output.

 

 

>>> What sort of quality penalty, if any would I be incurring by performing this action in 8 bit.

 

Best to run an experiment to see if there's a significant quality penalty with respect to your needs. It's easy.

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<p>none, sharpening should be done at the end of post processing, after all color adjustments, and resizing for final output. As you always should convert to 8bit before printing, i would do that before sharpening also.</p>

 

 

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Wow...lots of wrongness in this post...in point of fact you would be better off adopting a sharpening workflow workflow not just a single pass at the end. See <a href="http://www.creativepro.com/article/out-of-gamut-thoughts-on-a-sharpening-workflow"><em>Thoughts on a Sharpening Workflow</em></a> by Bruce Fraser.

 

Second, it would be foolish to take 16 to 8 bit for printing...if you are doing the output yourself, you want Photoshop to do the transform from working space to output profile in 16 bits/channel otherwise you'll have wasted your time working in 16 bit in the first place.

 

Back to the OP, if you want the benefits of working in 16 bit/channel then you need to keep your image in 16 bit for the duration. You can't go into and out of 16 bit and expect the reap the benefits. Yes, 16 bit is slower because the file size is 2X the size of an 8 bit file. That's life...

<p>Jeff. Thank you, I was going to answer this but couldn't summon up the energy to do it. I have PK sharpener, based upon Bruce Frasers book that outlines capture, creative and output sharpening. It has been covered on PN many times and many ways. The OP should search out these threads. Better yet read Fraser's book. He is now deceased but still regarded as the best on this subject as well as color managment. As he says capture sharpening, done before cropping, is to correct for a small amount of sensor resolution loss of sharpness at the outset. Creative is to correct local sharpness issues and output sharpening is to establish sharpening based upon output size and desired resolution for specific types of media, i.e. web, print, publication etc. </p>

<p>Thanks everyone for your input. I didn't mention in my post that sharpening is the last thing I do before saving the file. Well, I am trying to decide if I should Sharpen then convert to 8 bit or convert to 8 bit and then Sharpen. There has been a lot of discussion on Pnet regarding 16 bit vs 8 bit but not much on how it affects Sharpening. The last post I found on this was in Oct of 2007 but it was not really definative so I decided to ask again.<br>

I do not know anything of the algorithims used by the Smart Sharpen filter. I have tried it both ways and cannot see a difference. But I may not be as critical as some. I was hoping to get feedback from someone who has tried both and could perhaps offer an explanation for their preference.</p>

<p>I have sharpened with PK sharpener, with smart sharpen, with unsharp mask at 16 and 8 bit and as far as I know there is no difference except 16 bit makes a larger and probably better file. I usually use 16 bit. I do not convert before printing. The only time I convert to 8 bit is when a plug-in requires it or I convert from Adobe RGB to sRGB to post on the web in jpeg which you cannot save in 16 bit. I use 16 bit for almost all of my printing after at least using capture and output sharpening either with the PK plug-in or using smart sharpen for capture sharpen and unsharp mask for output sharpening. </p>

<p>If the printer driver is converting the image to 8-bits, what is the advantage of sending the printer a 16-bit image? Please leave RIPs out of the answer. Also, printers that will accept 16-bit images don't count either as I don't own one. Let's just discuss the 8-bit printer driver and the 16-bit image. </p>

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<p>what is the advantage of sending the printer a 16-bit image?</p>

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<p>...it would be foolish to take 16 to 8 bit for printing...if you are doing the output yourself, <strong>you want Photoshop to do the transform from working space to output profile in 16 bits/channe</strong>l otherwise you'll have wasted your time working in 16 bit in the first place.</p>