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Crisp look? Sharpening in LAB?

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  #61  
Old 04-19-2012, 02:22 PM
kav kav is offline
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Re: Crisp look? Sharpening in LAB?

I'm only adding to this because of the discussion of prophoto (I keep wanting to type "profoto" like the lighting, bleh). Anyway if you guys are going to edit in that, be careful. It breaks details easily regardless of bit depth, and you can produce some wacky colors which if not handled correctly can cause more problems later. I guess it has some advantages if you need to contain highly saturated elements, but the irritating behavior is really really irritating. I'm not sure why Adobe doesn't just use an input profile internally in raw processing rather than converting the data into a generic profile. There has to be some conversion there given that it has to interpret the data relative to the camera type given the amount of variation between them. I personally work primarily with Adobe 1998. It works fine. You do have to be careful with saturated primary colors so as not to lose detail, but you'd have to be concerned with what will reproduce anyway. If you do any crazy s-curves when dealing with highly saturated colors, you're asking for trouble, but I see it frequently.
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  #62  
Old 04-19-2012, 02:26 PM
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andrewrodney andrewrodney is offline
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Re: Crisp look? Sharpening in LAB?

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Originally Posted by kav View Post
Anyway if you guys are going to edit in that, be careful. It breaks details easily regardless of bit depth, and you can produce some wacky colors which if not handled correctly can cause more problems later.
Can you provide some files or step by step instructions in how to break detail and produce wacky colors?

You do have to be careful, aware that there are “colors” (quotes on purpose) one can define numerically that don’t exist (fall outside human vision thus are not colors) in ProPhoto. I’d like to see an example of a raw process were this crops up however.
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  #63  
Old 04-19-2012, 02:34 PM
kav kav is offline
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Re: Crisp look? Sharpening in LAB?

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Originally Posted by andrewrodney View Post
Can you provide some files or step by step instructions in how to break detail and produce wacky colors?

You do have to be careful, aware that there are “colors” (quotes on purpose) one can define numerically that don’t exist (fall outside human vision thus are not colors) in ProPhoto. I’d like to see an example of a raw process were this crops up however.
I could probably look for some later. I meant during adjustment. If you're processing to that, it'll look exactly the same on your display as Adobe 1998 tagged output. I was saying that when it comes to painted adjustments in difficult surfaces (paint, fabric, skin folds) masking in adjustment layers can produce problems faster than it would in a smaller gamut.

On the topic of wacky colors, many people on here like curve layers a bit too much :p, and if they do that under prophoto, they can pick up a lot of unwanted saturation where it would not naturally exist.
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  #64  
Old 04-19-2012, 02:59 PM
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andrewrodney andrewrodney is offline
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Re: Crisp look? Sharpening in LAB?

ProPhoto (ROMM) RGB by Kodak has been around at least as long as 1999-2000 and used by a lot of people (consider ever raw image out of ACR and LR for one). Bruce Fraser did a lot of work for Kodak testing it, even on 8-bit per color images (which isn’t recommended) and didn’t provide any information I know of that there were issues other than dealing with numbers mathematically constructed that fall outside human vision (for example B255).

I can make wacky colors with or without adjustment layers in sRGB.

After working with Kodak, Bruce did write this piece on color spaces which include some information about ProPhoto:

http://www.creativepro.com/article/o...n-color-spaces

It’s dated in the discussion on color spaces revolves around which can contain the gamut of film! But a modern DSLR has a far wider (and quite different) “gamut” (quotes again on purpose as digital cameras don’t technically have a gamut), hence when Thomas Knoll decided on ProPhoto as a raw processing space, I’m pretty sure he do so with good reasoning.
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  #65  
Old 04-19-2012, 03:39 PM
creativeretouch creativeretouch is offline
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Re: Crisp look? Sharpening in LAB?

I agree with kav here. Some colours can be exported slightly over saturated, that's why I like to desaturate them in ACR and prefer to deal with them within Photoshop.

But I have to admit that Adobe made huge jump forward regarding dealing with highlights (I am talking about luminosity, obviously) in new ACR. That makes me very happy and after long, long time, I can say "Thank you, Adobe ..."

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  #66  
Old 04-20-2012, 04:50 PM
santoro80 santoro80 is offline
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Re: Crisp look? Sharpening in LAB?

Whats the difference between unsharp mask and smart sharpen?
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  #67  
Old 04-21-2012, 04:48 AM
RobertAsh RobertAsh is offline
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Re: Crisp look? Sharpening in LAB?

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Originally Posted by Der_W View Post
Sharpening in LAB has the benefit that you can create impossible colors (are they called that way in English as well?), e.g. a 100% white that is red or a 100% black green.
However this is in most cases only useful when you're intending to apply a whole lot of sharpening to your images that will completely blow your channels.
Hi Der W,

You are right. LAB can produce impossible colors. These colors can be 'impossible' using one or both of two definitions:
  1. Impossible for the human eye to discern
  2. Impossible for the output device to reproduce
One neat thing about LAB is that it maps those 'impossible' colors back into reproducible colors. Dan Margulis has a neat example in his LAB color book where he uses that remapping to fill in a blown-out area in a face with the surrounding flesh tone without masking. I've never used that technique but it's nice to know it's there if I need it

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Originally Posted by jarulex View Post
Hello Folks! LAB color seem to be the trendy stuff or the 'it' color of the season, but can really give something different to the beauty retouch?
Maybe in the right hands For me personally, I use LAB color for my fine art landscapes (often combined with RGB) and I use ProPhoto RGB for my fine art portraits (I get better flesh tones with RGB). Then I convert to Adobe RGB if I'm printing the images myself, or to sRGB if I'm sending them to a lab.

Both of the color spaces have their advantages. For me, LAB color makes color rendering and even some color corrections much easier than doing them in RGB. I'm getting better with RGB for color corrections but for color manipulation LAB makes it easier for me and provides effects that I like better.

Quote:
Originally Posted by kav View Post
I'm only adding to this because of the discussion of prophoto (I keep wanting to type "profoto" like the lighting, bleh). Anyway if you guys are going to edit in that, be careful. It breaks details easily regardless of bit depth, and you can produce some wacky colors which if not handled correctly can cause more problems later. I guess it has some advantages if you need to contain highly saturated elements, but the irritating behavior is really really irritating. ....
Agreed. In particular, I need to convert to Adobe RGB before printing images myself, or the blues can really go crazy.

Last edited by RobertAsh; 04-22-2012 at 09:48 PM.
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  #68  
Old 04-21-2012, 08:30 AM
santoro80 santoro80 is offline
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Re: Crisp look? Sharpening in LAB?

What do you think its better - unsharp mask or smart sharpen?
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  #69  
Old 04-22-2012, 09:45 PM
RobertAsh RobertAsh is offline
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Re: Crisp look? Sharpening in LAB?

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Originally Posted by santoro80 View Post
What do you think its better - unsharp mask or smart sharpen?
I would try both. That's what I did when I first started sharpening. Smart Sharpen gives you better control and allows you a choice of sharpening algorithms. I'd recommend searching for some sharpening tutorials, experimenting with different setting and see how it works for you. Use enlarged images cropped to 4x6 or 8.5x11 pieces to avoid wasting paper.

Nowadays I use Nik Sharpener Pro for sharpening. It does a much better job than I ever did with Unsharp Mask or Smart Sharpen. For me, even Nik's defaults work better than what I could ever do in Photoshop. Plus Nik provides useful enhancements like Structure which are more fine-grained than Unsharp Mask or Smart Sharpen.

For enlargements I use Alien Skin Blowup with sharpening set to None and then sharpen the enlarged image with Nik Sharpener Pro.

Undoubtedly the Sharpening gurus here can do similar or the same thing or better using only Photoshop but I've not been at it that many years and those two products do a good job and save me a lot of time and frustration.

Last edited by RobertAsh; 04-22-2012 at 09:51 PM.
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