custom portrait masking

Miss Heather wrote:

Hi there,
I have a portrait studio and a reasonable amount of photoshop experience. Some of my customers have enquired about customized manipulated photos which I’m confident I could do if I knew the techniques involved. I have searched the internet forth and back, and downside up, trying to discern a definitive method of capturing and separating a subject and pasting it in a new scene. So…
Starting from scratch. What is the best background to shoot against? white, blue, grey, and why?

I’d never use white. Seen to many photos destroyed from a white background. It reflects light, excessively, making lighting critical. Also, you must consider what colors the person(s) you’re photographing is wearing. Would you use a blue background, if they were all wearing a similar color blue? Of course not. Would you use a gray background, if the person you were photographing had gray hair? 🙂

Uni

I’ve done many experiments but get messed up with fine details such as hair. I’ve found that no matter how accurately I manage to build a mask, or layer mask, when I inevitably convert it to a selection things fall apart and become quite crude, hair disappears, large blocks appear etc.
I realize this seems like a silly question in this day and age but I’ve searched the web without satisfaction. I’ll upgrade to CS if necessary. Any suggestions? Links? Good books? Tutorials?

Heather

Miss Heather wrote:

Hi there,
I have a portrait studio and a reasonable amount of photoshop experience. Some of my customers have enquired about customized manipulated photos which I’m confident I could do if I knew the techniques involved. I have searched the internet forth and back, and downside up, trying to discern a definitive method of capturing and separating a subject and pasting it in a new scene. So…
Starting from scratch. What is the best background to shoot against? white, blue, grey, and why?

I’ve done many experiments but get messed up with fine details such as hair. I’ve found that no matter how accurately I manage to build a mask, or layer mask, when I inevitably convert it to a selection things fall apart and become quite crude, hair disappears, large blocks appear etc.
I realize this seems like a silly question in this day and age but I’ve searched the web without satisfaction. I’ll upgrade to CS if necessary. Any suggestions? Links? Good books? Tutorials?

Heather

There is no one perfect color for backgrounds to cut out later. I find that a contrast to the hair seems to work the best. Contrast in both luminosity and hue will help cutting later.

Another key concept is to make sure that reflected light from your background doesn’t hit the subject. It’s a huge pain to cut out a green background and then find all this green tint on the edges of your subject. So, put the background as far away as you can and still be in the frame. Well, at least behind the subject; you can easily erase outlying areas in Photoshop.

One more key concept is partial selection. Hard edge selecting will always show. Of course, there are a number of techniques to help that.

When I shoot with my green background, I usually start my mask by checking out the different channels in different modes. Look at them in RGB, CMYK, LAB, etc. Actually for green I usually end up with the "B" channel for LAB. What I’m looking for is contrast between the subject and the background. Then I save a copy of that channel.

The next step I do is to adjust the contrast to make it stand out. Levels typically works fine for this step. I find what works best is to get the contrast as much as possible while leaving the edges and see-through of the hair as partially masked as possible.

I use this mask to cut out/erase the background. I may have to do some manual editing of the mask, but it isn’t too hard to do. This also doesn’t always work perfectly for the hair – particularly blond hair. Blond hair has much more see-through than darker hair. So, I often have to do some careful selecting, feathering, and hue changes in the hair. This will keep the semi-transparency while getting rid of tint. That semi-transparency is key to having natural looking hair over your new background.

This all works fine with my green background. I need to play more with Photoshop CS’s Replace Color command, but so far I haven’t got it to work as well. Part of the reason is that I’m not just replacing the color; I’m doing a whole lot more to the backgrounds I create.

This doesn’t really work for ambient backgrounds that I didn’t use a solid color. I’m not usually lucky enough to have enough of either contrast to find a channel that cuts the background out so nicely. In that case, I have more hand work to do.

I usually start with the Pen tool to do a rough selection around the subject. Then I go to Quick Mask to start Brushing what I want or don’t want to be masked. I typically use a soft edged brush and often work with less than 100% opacity. It can help to Feather the selection before jumping into Quick Mask.

Yes, this takes some work and time. It also takes some trial and error. I’d like to find a faster more automatic way, but haven’t. I doubt I will with current technology. If anyone else can enlighten me, I would be grateful.

BTW, CS doesn’t help any of this a bit. CS will REALLY help a pro with other workflow issues that I have found to be great.

Clyde

Miss Heather surprised us all by writing:

Hi there,
I have a portrait studio and a reasonable amount of photoshop experience. Some of my customers have enquired about customised manipulated photos which I’m confident I could do if I knew the techniques involved. I have searched the internet forth and back, and downside up, trying to discern a definitive method of capturing and separating a subject and pasting it in a new scene. So…
Starting from scratch. What is the best background to shoot against? white, blue, grey, and why?

I’ve done many experiments but get messed up with fine details such as hair. I’ve found that no matter how accurately I manage to build a mask, or layer mask, when I inevitably convert it to a selection things fall apart and become quite crude, hair disappears, large blocks appear etc.

I realize this seems like a silly question in this day and age but I’ve searched the web without satisfaction. I’ll upgrade to CS if necessary. Any suggestions? Links? Good books? Tutorials?
Heather

I frequently do this myself.
I use Photoshop CS which has the "Extract" filter where you can trace the subject and then pull it from the background. I found in a studio, the single best ‘colour’ if grey can be called a colour, is flat, 18% grey, the same as a ‘grey card’. To make it easier with PS 7 and earlier you could back light the person which will harden the edges.

If you use a coloured background, the often fine shadow around the subject can become contaminated and make the end result look false. Your experiments appear (from your description) not to have had the edges ‘feathered’ which is nothing more or less than making the boarder transparent and blending from zero to full density.

Douglas

You might want to take a look at Corel Knockout which allows you to cut out images from the background even if you have flyaway hair present. If you are photographing against a single colour background, then this tool is brilliant. It even does a fairly good job on more complicated backgrounds, but there is more work involved.

You can get it from
http://www.compusa.com/products/product_info.asp?product_cod e=50277318&pfp=c orelsc

Watch out for wrap around of the link.

Hope this helps.

Martin

"Douglas MacDonald" wrote in message

Miss Heather surprised us all by writing:

Hi there,
I have a portrait studio and a reasonable amount of photoshop experience. Some of my customers have enquired about customised manipulated photos which I’m confident I could do if I knew the techniques involved. I have searched the internet forth and back, and downside up, trying to discern a definitive method of capturing and separating a subject and pasting it in a new scene. So…
Starting from scratch. What is the best background to shoot against? white, blue, grey, and why?

I’ve done many experiments but get messed up with fine details such as hair. I’ve found that no matter how accurately I manage to build a mask, or layer mask, when I inevitably convert it to a selection things fall apart and become quite crude, hair disappears, large blocks appear etc.

I realize this seems like a silly question in this day and age but I’ve searched the web without satisfaction. I’ll upgrade to CS if necessary. Any suggestions? Links? Good books? Tutorials?
Heather

I frequently do this myself.
I use Photoshop CS which has the "Extract" filter where you can trace the subject and then pull it from the background. I found in a studio, the single best ‘colour’ if grey can be called a colour, is flat, 18% grey, the same as a ‘grey card’. To make it easier with PS 7 and earlier you could back light the person which will harden the edges.
If you use a coloured background, the often fine shadow around the subject can become contaminated and make the end result look false. Your experiments appear (from your description) not to have had the edges ‘feathered’ which is nothing more or less than making the boarder transparent and blending from zero to full density.

Douglas

In article <40713d59$>, Martin C
wrote:

You might want to take a look at Corel Knockout which allows you to cut out images from the background even if you have flyaway hair present.

I also see that Primatte Chromakey has just been introduced: http://www.digitalanarchy.com/section_psd.html

Tom Nelson
Tom Nelson Photography