Luminosity masking: part one / 15 comments + post
online tutorials

This is the first of a two part series of tutorials on luminosity masking, a powerful technique that you can use to selectively enhance your images. Unlike conventional masking techniques, which often require you to manually create a specific selection to mask an area of an image (and then feather, or otherwise alter the mask to blend the change with the remainder of the image), luminosity masking creates selections and masks that based solely on the brightness of the pixels themselves. As such, masks created using this technique often blend seamlessly with one another and the unchanged areas of the image, obviating the need to predetermine the selection area, or repair/refine the mask subsequent to its use.

Both parts were co-written with Tony Kuyper, a recognised authority in this field.

oldest comments first
comment by Roger at 02:06 PM on 1 May, 2010

Another outstanding tutorial David filled with the most detailed information and is definitely one to keep returning to. I will definitely be using these techniques in the future... Had a look at Tony's site and the images are breathtaking. Thanks for sharing this with us :-)

comment by Bill grisaitis at 10:59 PM on 4 May, 2010

Wow this another great tutorial explained clearly with great examples. Thanks from central florida!

comment by krizzo at 03:04 PM on 6 May, 2010


OH! This is excellent! I had not known about luminosity masks and this plus Tony Kuyper's website are a revelation. Thanks so much! I have a question (perhaps it was answered in another tutorial and if so apologies for missing it), but I wondered if using the luminosity layer mode has any advantages or disadvantages? I noticed on your Example 1 downloadable file that your curves are on "normal". The masks are "normal". The color change layer is "color". Thoughts?

comment by djn1 at 04:18 PM on 6 May, 2010

Roger and Bill: thanks.

krizzo: the masks could be used in conjunction with Luminosity blend mode, as can any adjustment. The advantage of doing this would be that you could adjust the luminosity of the masked area without significantly affecting the saturation. For the images in the tutorial, this wasn't an issue - the increase in saturation was a good thing - but for other images it would be less appropriate. In essence though, this is a decision that you'll need to make on an image by image basis.

I hope that answers your question, but get back to me if there's anything else you would like to ask.

comment by Justin Photis at 03:48 PM on 7 May, 2010

David, like the other comments before mine, this is a tutorial and a half alright, packed full of useful information.

As you said in your round-up and Tony's opening remarks, the concept can be difficult to understand at the beginning, but the Luminosity Masks seem to me like the perfect solution for those images that need miltiple masks and curves, with the inevitable problems with accuracy and feathering. A very inetersting read indeed. Thanks. JP

comment by Florian at 10:10 PM on 9 May, 2010

Great tutorial, again! I have been trying to use these already and the luminosity mask technique seems super useful. Thanks for sharing!

comment by Jean Eichenlaub at 03:01 PM on 10 May, 2010

This is a wonderful tutorial. Makes perfect sense in theory. Now I need to get the practice.

Slightly off topic question -- Is it necessary to convert to RGB to print with inkjet printer?

I read that inkjets actually convert from RGB to LAB to print. If so, then converting back to RGB might not be necessary.

comment by djn1 at 03:46 PM on 10 May, 2010

Justin and Florian: I'm glad you like it.

Jean: if you're printing from within Photoshop then the colour space you're working with isn't really relevant. If you're sending work out though I'd definitely suggest converting to RGB first if the image is going to be printed on an inkjet as they don't convert to LAB first (at least not as far as I know).

comment by Jean Eichenlaub at 11:29 PM on 10 May, 2010

Thank you. I'm printing myself, so will stop converting back. LAB color is becoming my favorite. Luminosity masks may become even more of a favorite.

comment by Jonas (americanvirus) at 04:04 AM on 19 May, 2010

Great tutorial! This one was especially good because it really did cover some new ground. It does look difficult in theory, but I imagine as I start playing around with different combinations of luminosity masks on my own pics it will just start being intuitive. Thanks again for a great tutorial!

comment by steve deer at 01:44 PM on 20 May, 2010

dave

this is excellent... I really can't wait for the next installment! The only thing I found was that the naming of the various mask channels was confusing to my little mushy brain.

It helps me greatly to call the channels...

l
ll
lll
llll
d
dd
ddd
dddd
m
m+
M++
m+++
m++++

steve

comment by April Pinsonneault at 08:13 AM on 1 June, 2010

Hi Dave,

These two tutorials on luminosity masking answer to all of my frustrations. This is very inspiring. Of course; I am still trying to make sense of it all. I never did lamase training but I had to remember to keep breathing. I started to read it a second time and that was a little bit more comfortable. By next year I should be fine with it :) It would appear that a great deal of manipulation can be achieved with these techniques. Every kind of tonal and detail adjustment seems possible; and even a somewhat of an HDR result appears to be achievable here. I am curious to know what kind of limitations do you find with these techniques? Thanks for sharing all of this with us...

comment by james at 10:42 AM on 6 June, 2010

Interesting stuff, i noted my file size went up dramatically with the masks and I deleted them once I had a play around. File went from 400kb to over 1gb so something to watch.

comment by djn1 at 10:48 AM on 6 June, 2010

Thanks all.

James: yes, that is something to bear in mind as the masks contain a lot of data - hence the large file sizes.

comment by Justin (LightAsMagic.com) at 05:36 PM on 8 June, 2010

This was a fantastic tutorial. I learned an great deal of useful information here. I have very excited to begin applying it.

Thanks again!