Photoshop selection for Masks

burstintoflame81 · Jan 18, 2010

I am trying to make an intricate selection. I need to select a white walkway and also isolate rose petals laying on the ground so that I can mask those in addition to the white walkway and leave the ground unmasked. I tried using color range, but can only seem to get a good selection on the white walkway. If I choose the flower petals it doesn't select all of the red and eventually as I add more samples on the flowers it eventually selects 70% of the entire picture ( none of which is even remotely close to the shade the petals are ).

I guess I am just looking for an easier way to make this selection without having to manually paint out each petal. Also, is there a way to add to a mask? ( I know I can paint white and black, but if I create a mask using Color Range and then want to go back in and select another chunk using color range and then add that selection to a mask that was created with a seperate selection, how do I do that? I have many pictures that have this same setup and need the same adjustments so if I can figure this out I can probably save myself about 20 hours or work. Thanks in advance for any help anyone can give.

HikinMike · Jan 18, 2010

I just use the Brush Tool on a Layer Mask. I set my 'default' brush at 300px and Hardness at '0'. By using the '[' and ']' keys, you can increase or decrease the size of the brush. You can also select the opacity to refine image.

Hope this makes sense and hope it helps.

Big Mike · Jan 19, 2010

There are many different ways of making selections and you can then use those selections to add or subtract from your mask.

Have you tried the Magic wand tool? Give it a try and remember that you can adjust the 'sensitivity' of it. I might start with a setting of 20, but then move down to 15, 10 etc. as the areas have less contrast.

One good trick, is to use an adjustment layer, to boost the contrast of the areas that you are trying to select. For example, create a levels layer and adjust the sliders so that you have the most contrast between the areas you want to select and their 'background'. The photo might look terrible but that's OK. Make your selection, then trash the adjustment layer.

Similarly, you can use the channels tab to view only certain color channels. Try looking at the image in only the red channel, for example. You may see that it has much greater contrast, and thus would make it easier for you to make a complex selection.

Once you have your mask, you can add or subtract from it in many ways. The simplest is, of course, to use the brush and paint it white/black/grey. But you can also use the selection methods. Just make a selection and then right click on the mask (in the layers palette). It will give you options to 'add selection to mask' and 'remove selection from mask'.

Also, there is the 'quick mask mode' (q), which is for making/viewing your selection. It basically gives you an opaque color overlay so that you can easily visualize the selection. You can use that mode, or just recreate the effect by adding a solid color layer and adjusting the opacity to where it works for you. Create this layer behind the layer with the mask, it is then very easy to see your mask as you paint it on and off.

burstintoflame81 · Jan 19, 2010

Big Mike said:
There are many different ways of making selections and you can then use those selections to add or subtract from your mask.

Have you tried the Magic wand tool? Give it a try and remember that you can adjust the 'sensitivity' of it. I might start with a setting of 20, but then move down to 15, 10 etc. as the areas have less contrast.

One good trick, is to use an adjustment layer, to boost the contrast of the areas that you are trying to select. For example, create a levels layer and adjust the sliders so that you have the most contrast between the areas you want to select and their 'background'. The photo might look terrible but that's OK. Make your selection, then trash the adjustment layer.

Similarly, you can use the channels tab to view only certain color channels. Try looking at the image in only the red channel, for example. You may see that it has much greater contrast, and thus would make it easier for you to make a complex selection.

Once you have your mask, you can add or subtract from it in many ways. The simplest is, of course, to use the brush and paint it white/black/grey. But you can also use the selection methods. Just make a selection and then right click on the mask (in the layers palette). It will give you options to 'add selection to mask' and 'remove selection from mask'.

Also, there is the 'quick mask mode' (q), which is for making/viewing your selection. It basically gives you an opaque color overlay so that you can easily visualize the selection. You can use that mode, or just recreate the effect by adding a solid color layer and adjusting the opacity to where it works for you. Create this layer behind the layer with the mask, it is then very easy to see your mask as you paint it on and off.

Awesome, I didn't think of altering the picture first to get a better selection. Thanks for the tip, thats exactly the type of advice I was looking for. I will give it a try today.

burstintoflame81 · Jan 20, 2010

Well, I chose a selection with ColorRange and created a mask in a saturation panel. then created another selection using ColorRange. However, when I clicked "Add to mask" on the same mask, it brought up more "marching ants" on the screen and left the mask the same. I am confused. Any help would be great.

Big Mike · Jan 20, 2010

OK, I think I messed up the advice on my last post. When you have your selection and then click on the mask, it lets you 'add mask to selection', which isn't really what we wanted. But we can still make it work.

OK, so you've got your mask and you want to add to it so you make a selection. You can then use the bush took and paint over the selection with a large brush (make sure that the mask is active and not another layer). Since you have an active selection, the brush will only paint in the areas that are selected, so you don't have to be precise.

Another way to do it, would be to go ahead and click 'add mask to selection'. Then your total selection will be the shape of the mask that you want. You can then right click on the mask and and delete it. Then simply use your selection to create the new mask.

There are probably easier ways, but that's all I can think of for now.

Dominantly · Jan 20, 2010

Read over this page, and check out how their program works.
It's free to try for 30 days, so why not see if it makes your life easier (it did mine).

Topaz ReMask - Masking Made Easy

burstintoflame81 · Jan 21, 2010

Big Mike said:
Another way to do it, would be to go ahead and click 'add mask to selection'. Then your total selection will be the shape of the mask that you want. You can then right click on the mask and and delete it. Then simply use your selection to create the new mask.

There are probably easier ways, but that's all I can think of for now.

Thats what I ended up doing. Just deleting and adding a new mask. Seems to work. You would think Adobe would make it easy to simply click and add to the mask. Seems overly complicated. I know you can paint to add, but with all the selection methods, they should ALL be able to add to the mask. Oh well. Thanks for the help.