How to make a perfect selection of hair ?

[loornard]

Ciao,
This is my first time here, I m writing you because I hope someone can help me: I don't know how to make a perfect selection of hair.

I have some photos and I'd like to change the backgrounds but I can't select the hair...no chance with the pen or lazo, somebody told me I shoud use a mask but I don't know how to do it for hair?
Does anybody know step by step how to make a perfect selection of hair?

Thank you so much
Ciao
lorenzo

[WilliamD]

In a situation like this the first place to look for a mask is in a channel. Sometimes one channel will offer a lot of seperation between the hair & background colours. On this occassion there is little tonal difference & sadly not much colour seperation either. Try a dupe of the red channel, Levels, drag the left (dark) slider in a little & move the mid & right sliders way over to the left - this should give you the best shot at a mask that can be refined with the paint (or any other) tools.

You can develop this trick by duping the image & converting to any other mode, such as CMYK, and grabbing a channel from that image to make a mask. Here you might even be lucky with the K channel, as the hair is quite dark & the back ground quite neutral, so may be lighter in the K. Incidentally, you can go even further if you're really keen/desperate: You can control the K channel generation.

Apart from that, IMHO the best application (disguised as a plug-in) for this kind of masking job is Knockout. A bit of a pig to use, but I've never found anything better for hair masks & I've had to do a ton of them over the years.

Good Luck!

[philbach]

Why don't you post a larger size image. With a bigger file like 800 x 600 pixels you might be able to get more specific instructions from members of this group.

What I've seen a lot of the pros do is to shoot these shots with a high key white background. That makes extraction a whole lot easier.

[venivedi]

I agree with philbach.
Oh?! you can also use 'difference blending mode' with 2 photos. I mean...one with background and object...and the other with only background...of course they should be taken at same lighting circumstance.

By the way, here are my example...I hope that to be some help.

[WilliamD]

Blending modes can help, but on their own often leave halos, as in the lit strands at the top of your example, which have dark halos from the original background.

If you are going to re-shoot on a different background give thought to 1) the colour & luminosity changes you will be making on the background 2) Your prefered method of masking/blending 3) The hair colour of your subject e.g. avoid blondes on white backgrounds if you want to go to a dark colour!

Hope that helps.

[venivedi]

Thanks a lot WilliamD for pointing out my mistakes and making suggestion.

[CJ Swartz]

Russell Brown, a Photoshop guru, has an excellent Quicktime movie tutorial online that will show you how to get started -- it explains some of the good ideas above. Read, watch, and then practice, practice, practice!

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Note: may require broadband connection -- some folks on dial-up faced 40 min. downloads and then the tutorial didn't work correctly -- it's an excellent piece to look at IF you have a fast connection.
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http://www.russellbrown.com/images/t...cedMasking.mov

[Flora]

Ciao Lorenzo,

Welcome to RP!

You got great tips on how to do this .... particularly CJ's link and tip are a must in these cases!!!!

For your picture, I found that the 'Channel Masking' suggested by William was more than enough...

Last year, I actually wrote this Tutorial about using Channel Masking in difficult selections .... If you've never done this before, it might be worth reading as it takes you through it step by step....

For your picture I used the Blue Channel as the one with the better contrast between hair and background ....and, to increase its contrast, I used Image>Adjustments>Brightness&Contrast instead of the Levels....

Hope this helps .....

P.S. Please.... help us to help you ..... posting an image which is slightly bigger than a postage stamp makes working on it very, very difficult and, sometimes, downright impossible .... Our Help requested and Restoration, Retouching, and Manipulation Forums provide links to instructions about size, and resolution for posting images at RP or you can just follow the bottom link under my signture .... Thank you ....

[Gary Richardson]

Hi CJ, have tried your link. Using dial up, I have "appeared" to download it successfully using both Firefox and IE only to find I've got the sound but no video. Really frustrating since the download on both occasions took about 40 mins. So I think I'll be giving this one a miss. I am using the latest version of Quicktime.

[saby]

Hi Lorenzo!

A quick method to mask the hair:

1. save a copy of orig.
2. chechk the best channel of contrast (usualy blue)
3. channel mixing: set blue fill it 100% red and 100% green
switch monocrome button decrease contrast (if it needed)
4. mode: gray
5. open: orig
6. split channels
7. merge channels as multichannel (your adjusted file is still open)
8. mode: RGB

some more curevs and brush and blur tools following
for fine-tunes use the smuggle tool very good

have fun
saby

[CJ Swartz]

Originally Posted by Gary Richardson

Hi CJ, have tried your link. Using dial up, I have "appeared" to download it successfully using both Firefox and IE only to find I've got the sound but no video. Really frustrating since the download on both occasions took about 40 mins...

YEEOUCH!! Very sorry, Gary and whoever else finds a similar problem -- I'll add a note to that post that it may require a fast connection. I'm lucky enough to use a broadband cable connection, but remember how frustrating dialup could be with big files.

[loornard]

Thank you all !
Your suggestion really help me,
thanks particularly to Saby, William and Flora , her Tutorial is really Great.
I can't find a forum like this in italy ...you guys really have a step more.
Grazie & Ciao
Lorenzo

[Gary Richardson]

Hi CJ, have been having more trouble with Quicktime opening inside browser, so did a repair install, this seems to have cured problem, so may have another go with russelbrown. I've got my fingers crossed this time.

[Gary Richardson]

Just successfully opened and saved russell's excellent tutorial. Thanks for the link CJ, it brought to my attention the problem with my copy of Quicktime, and gave me an excellent tutorial on masking. Must have been the crossed fingers that did it.

[CJ Swartz]

and a big YIPPEE !!!