Your best masking techniques.

KR1156 · #1 09-21-2006, 02:37 PM

Lately there's a lot of work on skin going on, i would love to see everyones effort on an image that requires a lot of masking work, something high-end, like a shot of a female model with plenty of flowing/fly-away hair, etc. Where she needs to be totally silo'd from her background, and placed onto another flawlessly.

I have the perfect image for this, but can't get the photog's permission...does anyone here have any images they would like to provide for learning purposes?

I would love to see everyone's techniques and input, there are a lot of talented ppl on here...i think anyone who is interested in high-end beauty retouching would greatly benefit this "challenge"

-any takers?

pellepiano · #2 09-21-2006, 03:08 PM

Heres an example of mine.

http://www.pellepiano.com/studiobild...s/imageb14.jpg

I find the extract tool can give a pretty good start and the Russell Brown Layer Mask method is good but quite timeconsuming.
I shoot against a bluescreen.

KR1156 · #3 09-21-2006, 05:16 PM

extract is great when you have the contrast to work with, i would love to see how people manipulate channels to get their refined mask,,,what techniques are out there. what people are doing to separate those flyaways from a background with no contrast.

i have the masking book by katrin eisman, which is really good.

bart_hickman · #4 10-06-2006, 02:22 AM

Quote:

Originally Posted by KR1156

extract is great when you have the contrast to work with, i would love to see how people manipulate channels to get their refined mask,,,what techniques are out there. what people are doing to separate those flyaways from a background with no contrast.

i have the masking book by katrin eisman, which is really good.

NO contrast? Well there's got to be some contrast. Here's a pathalogical one to torture yourself with:

http://www.pbase.com/zumbari/image/6...7/original.jpg

Bart

Daviskw · #5 10-07-2006, 12:50 AM

Well sure not my best ... bart that is a tough one. I think if I spent a little more time on the puppy's back edge it would not come out too bad... just more work than i want to do now... But if i was of a mind all it would take was a little work on the mask and some blurring.

To get where I am...

Duplicated the background

I used the pen to make a outline . Then converted the outline to a alfa channel. Then used that channel along with the extraction tool.

Made a selection mask of the extracted dog. and attached it to the duplicate layer... then erased the extracted layer.

Inserted my picture in the middle.

Butch

bart_hickman · #6 10-07-2006, 01:00 PM

Excellent job Butch. I didn't post my extracted version because it's a lot harder to explain than it is to do.

I usually start with the extract tool, then plan B is the background eraser. In this case I didn't think extract would work, so I skipped to the BGE which handled about 70%. 20% was image-based masking, 10% was manually erasing with a stipple brush (the part of the dog that has no contrast at all).

First attachment shows the beginnings of BGE work. After using the BGE, I do the rest of the extraction using other methods and I'll focus on a section extracted using image-based masking (more or less what Russell Brown describes in his video tutorial.)

In the places where the BGE doesn't work well, this image has some contrast information in all color channels,not just one, so I use the info from all three. The second attachment shows how that works.
1. Original
2. Sample the hair color near the edge of the hair, but where the hair completely blocks the background. Floodfill a new layer with this color and set blend mode to difference--now the edge hair is black, and everything else is some other color.
3. Add channel mixer--set the coefficients to 50,50,50 Could have done 100,100,100--the import thing is they are equal because I'm using information from all three channels equally. Choose monochrome to convert the color difference into a greyscale image.
4. Add a levels control to accenuate the contrast
5. Use a brush to clean the areas away from the edge of the hair. Good idea to make a marquee selection in case you accidentally slip while brushing.

That's my 2-minute tutorial on converting information from all channels into a single mask.

There's more finish-up work I'll describe later--gotta go right now. As a preview, the final attachment is my final result.

Bart

Kraellin · #7 10-07-2006, 08:47 PM

this is all mask, back and forth, black and white. i added the neutral gray to really show the work. masks are great because you never have to alter the work itself, just the mask.

craig

Gary Richardson · #8 10-08-2006, 01:49 AM

This is mine, made from the red channel.

Got it something like, then adjusted the mask using levels. Final tweaking done with a low opacity black/white brush.

BillFrey · #9 10-08-2006, 06:46 AM

My masking didn't turn out great, so I used hair brushes to fix it up.

Ying · #10 10-08-2006, 09:10 AM

I have a question: What if you need to extract a grey object from grey background?

I had to do this type of work a while ago and ended up creating custom clipping paths, which took forever to draw and adjust!

Attached is an example:

Gary Richardson · #11 10-08-2006, 11:23 AM

In this case there was quite good contrast, and the extract tool did a passable job, needed a little hand touching with eraser and history brush, but whole job only took about 5 mins.

Of course if getting in really close, a clipping path will be the route of choice because of the crisper edge definition.

bart_hickman · #12 10-08-2006, 06:41 PM

Well I didn't challenge you guys at all--nice work one and all. Okay, I'll have to dig up something more difficult.

Bart

Kraellin · #13 10-09-2006, 08:01 AM

Quote:

Got it something like, then adjusted the mask using levels.

now that's an interesting idea, gary. i sometimes blur the masks but hadnt thought that much about using adjustment layers on them. good tip!

bart,

we've had some wild challenges like this in the past. it's one of those areas that i wish Paint Shop Pro did a better job of. i did notice when i was working on this image that psp xi has changed some things in the magic wand, so going to have to study that a bit more. it's always struck me a bit odd that the human eye can discern the differences necessary but that the graphic editors cant seem to very well. ah well, gives the coders something to work on, i suppose

craig

bart_hickman · #14 10-09-2006, 08:54 AM

Quote:

Originally Posted by Kraellin

we've had some wild challenges like this in the past. it's one of those areas that i wish Paint Shop Pro did a better job of. i did notice when i was working on this image that psp xi has changed some things in the magic wand, so going to have to study that a bit more. it's always struck me a bit odd that the human eye can discern the differences necessary but that the graphic editors cant seem to very well. ah well, gives the coders something to work on, i suppose

craig

Hi Craig,

Two reasons for this. 1) you (your brain) interpolates to find patterns where none exist, 2) not only can you see the boundary between color changes, but you can also see the boundary between texture changes.

In both of these cases, I just get a stipple brush and create the boundary I think I see in my mind's eye.

Photoshop is very productive for multistep extractions like this--the UI seems really geared for effortless manipulation of masks and selections and conversions between paths/selections/masks.

As for PSPXI, I was put off by the fact that the levels adjust tool has had the output slider removed--something I use quite a lot.

Bart

Kraellin · #15 10-09-2006, 12:00 PM

bart,

yes, and the mind plays tricks at times

but yes. i think it also may be a flaw in the entire digital system, at least the rgb system. this is something i've been studying recently and havent fully grasped yet. it's somewhat an inherited system from a time when computers were much more limited. it's probably also why LAB came about; someone else felt the same way, apparently. it's a bit limited that we divide the entire light spectrum into only rgb; why not rgbcmyk...or even more? i'll work on it

as for the levels tool, i noticed but wasnt concerned. i actually use levels a lot less than most here. and they did add white/black/gray points to it. i suppose that was their solution to the output part. but yes, in general, i hate when they take away a favorite function. you could always put it back, you know. there is that customization feature in Paint Shop Pro. i've added back quite a few things.

craig