PS101 Group C - Selection Tools & Masks

05/12/2007 07:14:57 AM · #1

BAMartin,

meyers,

Delta_6,

jackal9,

jonfrommk,

juniemoon,

krnodil,

liltritter,

American_Horse,

ingridblue,

mamba

WORKING WITH SELECTION TOOLS & MASKS
Mentor for this Group & Topic:

simms
Topic Author: Art Roflmao

Introduction and Disclaimers
This, and all other lessons put together by me are mostly right out of my head based on my experience. I learn new things about PS everyday, so I encourage everyone to participate in the discussion on the use of tools and methods. You should also feel free to post links to additional resources related to the current topic. Always remember that there is really no "right" way to do anything in Photoshop - find what works best for your style and comfort level.

SELECTION TOOLS
The various selection tools in PS allow you to isolate parts of an image to apply effects or filters to just that area or to copy or cut out an area. There are actually a lot of ways to "select" parts of an image: use a selection tool, CTRL+A (select all), Select Color Range and also variations of some of these.

The primary selection tools I use are the Marquees and the Lasso tools:

- Selects a rectangular area. You can hold SHIFT to constrain the selection to a square. Option settings include a fixed size and fixed aspect ratio - both can be useful for cropping or copying consistent shape and size images.

- Selects a round or elliptical area. You can hold SHIFT to constrain the selection to a circle. Option settings include a fixed size and fixed aspect ratio. This one also has the Anti-Alias setting which softens jagged edges.

- These select a single pixel horizontal or vertical row or column from edge to edge. I have used this for very unique purposes before, but don't find them all that useful.

- Good for rough freehand selection. Hard to control precision even with a tablet and once you let go of the mouse button, the selection is closed/completed for you.

- Good for detailed work and straight edge selections - zoom way in and click from point to point, tracing edges of the part of the image you want to select. Use the spacebar and drag the image to reposition as you go.

- Good for detailed work, but only works well on high contrast edges, but provides a quick way to remove a subject from it's background. Takes some practice to get the tolerance and smoothness settings dialed in to work for a particular image.

- Good for selecting / removing large areas of solid or similar colors. Options allow for contiguous selection or selection of all colors within the tolerance setting. Can be used to work on the contents of a single layer or All Layers. The All Layers option will apply to creating the selection but keep in mind that when you apply filters and effects, they will only be applied to the contents of the selection on the active layer.

- You can ADD to a selection by holding down the SHIFT key and you can SUBTRACT from a selection by holding down the ALT key when using the selection tools. If you accidentally click without pressing a key to add or subtract and lose your selection, just UNDO to get it back. Also remember that the lasso tools have additional options that can be set on the options bar. These include "feather", which will softent the edges of the selection. I rarely use the feather options on a selection tool since I can feather the selection when I am done building it.

For any selection tool that requires fairly high contrasting edges, you can use CTRL+J to duplicate the current layer (assuming everything you want to select from is on this layer), then adjust the contrast, levels, curves for maximum contrast on the edges you want to select. Build your selection on this layer, then switch to the original layer, hide or delete the high contrast duplicate and perform whatever action on your selection now on the original image layer. This works especially well with the magnetic lasso.

Using only the lasso selection tools, remove the subject from its background and place it on a solid white background. Post your completed image thumbs here for discussion and feedback. You can either use this image below, or use one of your own, but try something challenging - not something like an already silhouetted subject. If you use your own, also post the original thumb.

That's all I have time for right now. I will post the subtopic: "Masks" in this same thread in a day or two. Some of this is very basic, but it is a 101 class, so bear with us or check back as the topics are posted if these are too fundamental for you or chime in with your tips & tricks.

krnodil

Canon EF 100mm f/2.8L Macro IS USM

05/12/2007 08:21:29 AM · #2

Ok, I tried the squirrel selection two ways:

First I tried the tip for making a high contrast layer and using the magnetic lasso tool to select. This didn't work so well, likely because there's not a lot of contrast and color difference between the squirrel and the surrounding gravel.

Second, I tried using the polygonal lasso, with the image magnified to 200%. I had far more control over the selection this time, especially when selecting the feet, although the image was so pixelated at this magnification that I had trouble distinguishing where the squirrel ended and where the gravel began.

I tried adding feathering to this second selection (not pictured), but frankly can't see any difference no matter what feathering amount I used - don't know if I'm doing something wrong there, all I did was change the amount in the box, am I supposed to click on something else to "activate" it?

I'd like to know more about how to select things that have very fine edge detail, like this squirrel, where you have a lot of fur strands making up your edges. Is there any really good way to mitigate the cutout look such subjects have when you select them, without having to resort to blurring the edges?

Message edited by author 2007-05-12 08:21:42.

krnodil

Canon EF 100mm f/2.8L Macro IS USM

05/12/2007 02:48:33 PM · #3

*bump*

suemack

Canon EOS-20D

05/12/2007 05:22:09 PM · #4

Hiya Karen, I blew my squirrel up to 300% and tried zig-zagging with the tool around that tail edge to give a more natural looking result (over did it of course). This was a tough assignment wasn't it.

ETA wrong group, but never-no-mind, we're all squirreling together :))

Message edited by author 2007-05-12 17:23:40.

05/12/2007 07:38:27 PM · #5

sorry, not to brag or anything, but, my skills in extracting images are a bit better than some tool on the tool pallet.

still 'gonna wait 'til this thread gets into the thicker beef of the brisket.

05/12/2007 10:50:45 PM · #6

Hope to get to trying this. didn't see the assignment untill 11 p.m Need to go to bed. Thanks for this one. I don't know anything about extracting.

05/13/2007 02:38:58 AM · #7

Ok - looks like

simms is unavailable today. Sorry, I should have checked in here earlier.

Originally posted by American_Horse:

sorry, not to brag or anything, but, my skills in extracting images are a bit better than some tool on the tool pallet.
still 'gonna wait 'til this thread gets into the thicker beef of the brisket.

I mentioned in one of the other threads, that the lasso tool is not the best extraction tool, but using it for an extraction helps learn the ins & outs of how the various lassos and their options work. Certainly if you feel the topic is below your level you are free to skip it and there is no need or usefulness in posting that you are not going to participate - just don't - nothing is going on your permanent record. ;-) But you are also free to jump in and help out with feedback on others or answer questions that may be getting stale.

Also keep in mind that this being a PS101, or "Basic" photoshop class, you may end up going hungry since there won't be any "beef" until an advanced class. You can review the list of topics that will be covered in this workshop here...

05/13/2007 03:08:49 AM · #8

And now for the second part of this topic...

MASKS

For this part of the topic, I am going to cheat a little and copy/paste some info directly from the PS help file.

Originally posted by Adobe Photoshop CS Help File - About Masks:

Masks let you isolate and protect areas of an image as you apply color changes, filters, or other effects to the rest of the image. When you select part of an image, the area that is not selected is "masked" or protected from editing. You can also use masks for complex image editing such as gradually applying color or filter effects to an image.

Masks and channels are grayscale images, so you can edit them like any other image. With masks and channels, areas painted black are protected, and areas painted white are editable. Masks let you save and reuse time-consuming selections as alpha channels. Alpha channels can store selections so you can use them again, or you can load a saved selection into another image.

Photoshop lets you create masks in the following ways:

Quick Mask mode

Lets you edit any selection as a mask. The advantage of editing your selection as a mask is that you can use almost any Photoshop tool or filter to modify the mask. For example, if you create a rectangular selection with the Marquee tool, you can enter Quick Mask mode and use the paintbrush to extend or contract the selection, or you can use a filter to distort the edges of the selection. You can also use selection tools, because the quick mask is not a selection. (See Using Quick Mask mode to make selections (Photoshop).) You can also save and load selections you make using Quick Mask mode in Alpha channels.

Alpha channels

Lets you save and load selections. You can edit Alpha channels using any of the editing tools. When a channel is selected in the Channels palette, foreground and background colors appear as grayscale values.

Layer masks and vector masks let you produce a mix of soft and hard masking edges on the same layer. By making changes to the layer mask or the vector masks, you can apply a variety of special effects.

The only thing I am going to add is my endorsement of Quickmask mode - I only recently started using it and it is great for doing detailed selection work.

The only assignment on this part of the topic is to experiment with it.

Remember "Q" takes you into quickmask mode and also toggles you back out. When in Quickmask mode, the masked part of the image (UNselected part) is the colored part - you paint the mask in with a pencil or brush. If your brush opacity is less than 100% when masking, whatever you do to the resulting selection will be applied accordingly.

--------------------------
**Don't worry if you are one of the group members and are just catching up with the thread - feel free to apply the use of quickmask mode to the original assignment and see if it makes things easier than the lasso tool. I won't be posting the next topic for a few days, so go ahead and experiment, post experiences, discuss, tawk amongst yuhselves. :)

05/13/2007 10:06:18 AM · #9

Hi guys,
sorry I was a bit useless with the assiting on the last topic, paid work comes first I am afraid. Anyway, virutally up to date on getting photos out to those happy couples now so should be able to spend a couple of hours a day helping out.. feel free to email/PM me if you are stuck on a particular area, I always answer my emails.

Anyway, I will post my take on Arts assignment shortly. If you can all take a few moments out at some point to thank the man for putting this all together I am sure he will apprieciate the feedback.

Cheers, Mark

Message edited by author 2007-05-13 10:07:42.

05/13/2007 10:22:18 AM · #10

Originally posted by Art Roflmao:

But you are also free to jump in and help out with feedback on others or answer questions that may be getting stale.

Also keep in mind that this being a PS101, or "Basic" photoshop class, you may end up going hungry since there won't be any "beef" until an advanced class. You can review the list of topics that will be covered in this workshop here...

Sorry if I ruffled your feathers.

I have my name to this list for the basic as a reference. To see other ways of doing things.

I made the said post only because I do not want to seem not interested, and not a participant.

It is not that it is beneath me KEN, but, simply just waiting patiently, watching, drinking in, standing by, simmering, hibernating in the shadows, listening, reading, taking in.....................

Just to be clear, I have jumped in at least once, to answer a question. But, this is your party, and I am just a guest, partier, passerby, pedestrian, drunk, bar fly, beer fan, lush........

Originally posted by Art Roflmao:

Alpha channels

Lets you save and load selections. You can edit Alpha channels using any of the editing tools. When a channel is selected in the Channels palette, foreground and background colors appear as grayscale values.

The only thing I am going to add is my endorsement of Quickmask mode - I only recently started using it and it is great for doing detailed selection work.

I have to disagree with the Quickmask assessment of being great for detail.

When using an Alpha Channel selection, you have two thing in your favor.

1) Greater detail of fractals. IE, hair, branches, trees, ect..

2) There is a great deal less of hand drawing from using an Alpha Channel selection than there is in using a Quickmask.

Believe me when I say, that after an hour of 'hand extracting', getting all the details in this way, will be tedious, and you hand will ache.

Message edited by author 2007-05-13 10:35:44.

05/13/2007 10:30:56 AM · #11

Horse,
if you ever see techniques posted on here and feel that a way you know is better then it would be great to post on here, I am with Ken by saying I learn new things about photoshop every single day, so anything I can learn on here whilst helping others really would be beneficial!

Cheers matey!!

Mark

05/13/2007 10:33:16 AM · #12

TIP!!

Some useful keystrokes.

Shift+D will turn off your current selection.

Shift+Ctrl+D will turn the selection back on.

05/13/2007 10:40:58 AM · #13

Originally posted by Simms:

Sorry, your too quick.

Edited my post to include an observation.

05/13/2007 11:11:54 AM · #14

OK, here is my attempt, using the magnetic selection tool on a high-contrast layer.. I have also included a `stroked` version to give you a better idea of the selection.

Taking your time really is the key, it is dull-work but a good mask/selection helps out in the long run.

HINT.
For those of you who want to investigate further, Extensis Mask Pro v3 is an incredible tool for complicated selctions with some very powerful weapons in its arsenal to create the perfecct selection. I will attempt this squirrel pic a bit later on to show you what it is capable of.

Message edited by author 2007-05-13 11:13:41.

05/13/2007 12:32:47 PM · #15

Originally posted by krnodil:

I'd like to know more about how to select things that have very fine edge detail, like this squirrel, where you have a lot of fur strands making up your edges. Is there any really good way to mitigate the cutout look such subjects have when you select them, without having to resort to blurring the edges?

OK, you had far better results with the polygonal lasso method, which is obvious from even the thumbnails.

Art was a bit sneaky with this shot due to the incredibly close colours/contrast between the squirrel and the background. On a shot like this, as far as I can tell using the standard suite of photoshop tools, patience will be your best friend. Hopefully Art will be kind enough to find an image for you guys to practice on, maybe splashing water.. Lots of different selections to be made on an image such as that with different techniques able to be applied to each area (the main splash, the droplets etc).. I wont hijack his tutorials though.. merely suggestions :-)

Tamron SP AF 17-50mm f/2.8 Di II LD Aspherical (IF) for Nikon

05/13/2007 03:42:01 PM · #16

Originally posted by Simms:

HINT.
For those of you who want to investigate further, Extensis Mask Pro v3 is an incredible tool for complicated selctions with some very powerful weapons in its arsenal to create the perfecct selection. I will attempt this squirrel pic a bit later on to show you what it is capable of.

Good tip! I used Extensis add-ons for many years, but PS native features started catching up with third party ones. I still use an old version of Extensis PhotoFrame filters for borders. We'll get into those later though.

Here's another tip I posted in the other groups:

One method for fixing up hair is to use a special brush for either erasing, or for quickmasking in the first place. I use the "Dune Grass" brush (for MANY things) and it can be adjusted in a zillion ways. Brushes can be used for burning, dodging, history brush, eraser, clone stamp and other things, so the many settings available for the brush in this palette make it very useful!

meyers

Canon EOS-6D

Canon EF 50mm f/1.4 USM

05/15/2007 12:03:28 AM · #17

I had trouble trying to create a high-contrast image that highlighted the edges of the squirrel, so I just used the polygon lasso. After my initial tracing, I did some additions and subtrations to try to get the missing pieces. This was fairly difficult; what's a better way to handle things like hair?

levyj413

Apple iPhone 15 Pro Max

05/15/2007 01:22:12 AM · #18

Layer masks: making masks permanent

Now that you're using the quick mask to create whatever shape masks you like, wouldn't it be nice to keep those selections? That's what layer masks do. Instead of marking out some selection and then actually deleting the rest, you tell Photoshop to only show what you want. But the rest of it stays there, so you can edit it the mask later if you want, adding and deleting as much as you like.

Art has asked me to take everyone through creating layer masks. I'm going to go through several steps as explanation, and then give you an assignment.

The first way we'll do this is using quick mask. So starting with the squirrel, I'm going to duplicate the original layer and then turn it off. It's always best to work on a duplicate.

Then using quick mask, I'll roughly mask it out (remember that I like to paint what I'm selecting, as opposed to what I'm masking - you can do it either way, but if you paint out the masked area, remember to invert the selection).

Next, I'll exit quick mask so you can see the selection:

I then create the layer mask using the layer menu. The exact location probably varies with the PS version, but here's how it looks in CS2:

Note that I can choose to reveal or hide the selection, so be sure you do what you intend. You'll see that whatever I didn't select disappears. But it's not really deleted - it's all still there, available to be added back in if you like.

Look at the layers tab. You'll see that next to the active image layer thumbnail is a new black and white box. That's the layer mask thumbnail:

In the layer mask thumbnail, the white shows the area that's visible and the black shows what's masked out:

So far, this is just like quick mask. The big difference is that the layer mask is completely editable. To edit the actual image, click on the thumbnail of that layer. But to edit the mask, click on the B&W mask box. For example, if I want to add a bit of the rocks in the upper left, I click on the mask and just paint in some white:

To remove some of the mask instead, I'd paint in black.

Three of the most powerful things to me about layer masks are that you can:
1) edit them
2) see them full size, and
3) temporarily turn them off:

It's often good to see the mask full-size, esp. to make sure you really painted it in as solidly as you like. To do that, alt-click on the mask thumbnail in the layers tab:

Alt-click again or just click on the normal image thumbnail to exit full-size mask view.

You can see that I didn't quite paint in solid white across the whole squirrel.

You also sometimes want to temporarily turn off the layer mask (for example, to make sure you didn't mask out something you really wanted to include). To toggle the layer mask on and off, use shift-click on the mask thumbnail. Note that while you're seeing the whole layer, the mask is still there, and can be turned back on again by shift-clicking on the mask thumbnail.

Now that you've seen how to create, edit, and toggle on and off layer masks, it's time for you to try it!

Layer mask assignment part 1: Using the original squirrel image, create a duplicate layer. Turn off the original layer so all you see is the copy. Now create a layer mask following the steps above.

Layer mask assignment part 2: Click on the layer mask thumbnail and edit it. Use the brushes, marquee and other tools, and other methods just like you did to tweak a quick mask. Try black, white, and grays to introduce various levels of transparency.

You can even apply gradients to the mask, which will apply smoothly varying transparency.

Layer mask assignment part 3: Now that you've created a layer mask beginning from a selection, try creating a blank layer mask using the layer menu - you can either reveal the entire layer or hide it, and then start painting in the mask as you see fit.

Extra credit: create a layer mask for an adjustment layer like levels. Adjustment layers automatically create layer masks (ever wonder what that white box was over to the right in the layers tab?) You can also create a selection first, and then when you then create the adjustment layer, the selection will be applied automatically as a layer mask.

Message edited by author 2007-05-15 01:45:20.

Tamron SP AF 17-50mm f/2.8 Di II LD Aspherical (IF) for Nikon

05/16/2007 07:17:05 AM · #19

Hi, all.

Not sure who to ask, but I had hoped I could do this workshop, but it is just too much for my schedule. I have been watching the thread, and have learned a bit, but can't keep with it. I just wanted to ask if I could be removed from the class. Maybe another time would have worked better, like in January when not much is happening. I have enjoyed the tips and techniques and will continue to look at it when I can, but don't have time for assignments.

levyj413

Apple iPhone 15 Pro Max

05/17/2007 11:31:50 PM · #20

Is anyone still out there?

I've found that for DPC advanced editing challenges, the main use for layer masks is for controlling various adjustment layers like curves, levels, and color changes (layer masks are selections, so are illegal for minimal and basic editing, and there are many more uses in expert editing).

But you can also have a lot of fun with "multiple personality shots" like my recent triptych entry. Take a look and then come back to learn how to do it:

At its simplest, this took three steps:

1) Shoot. Use a tripod and manual settings. You want the lighting to be the same for each shot.

2) Combine shots into one Photoshop file. First open one file as the "base" layer to provide the background for the others. Then open each additional shot and copy it as a layer into the base file.

One way to do that is to click and drag the new layer from the layers tab over to the base file and let go; it will then appear as a layer in the base file. You might need to move the layer once it's moved to get it aligned right.

3) Create layer masks . Just mask out the portion of each additional shot that you want to show. That way, minor changes in the background or lighting won't matter.

For my triptych, I used the leftmost shot as the base. Although there were a couple of girls chasing a ball in the background, I just masked them out of the other two shots.

Here's a composite showing the original three shots, the layer masks for the middle and right shots, and the final composite without the white lines:

You can get as complex as you want; changing clothes and hair really sells the effect well. The longer you take shooting outside, though, the more chance the light will change. And after you do the basics, watch for things like overlapping shadows, reflections, etc.

Set up a tripod (or just put your camera on a table), shoot a few pics, and make your own multi-personality shot.

Here are a few other examples to inspire you:

Bonus assignment: after doing it, try doing a triptych where part of one frame overlaps the other, like in the cartwheel shot above. You now have the layer masking tools to do it in any of various ways.

05/17/2007 11:50:15 PM · #21

Originally posted by JunieMoon:

June,

simply "Watch" the class. Don't quit. You can come back to it when ever.

I doubt anyone here would care if you couldn't do all the 'assignments'.

go to the top of the thread, on the left hand side, choose the menu that asks if you want to "Watch" , "Ignore", or what ever.

It would be a great loss to you if you just quit.

Delta_6

Canon EOS-7D

05/18/2007 03:08:35 AM · #22

I am in the same boat as JunieMoon. I will continue to watch and learn.

05/18/2007 03:14:38 AM · #23

Originally posted by American_Horse:

Originally posted by JunieMoon:
Hi, all.

Not sure who to ask, but I had hoped I could do this workshop, but it is just too much for my schedule. I have been watching the thread, and have learned a bit, but can't keep with it. I just wanted to ask if I could be removed from the class. Maybe another time would have worked better, like in January when not much is happening. I have enjoyed the tips and techniques and will continue to look at it when I can, but don't have time for assignments.

June,

simply "Watch" the class. Don't quit. You can come back to it when ever.

I doubt anyone here would care if you couldn't do all the 'assignments'.

go to the top of the thread, on the left hand side, choose the menu that asks if you want to "Watch" , "Ignore", or what ever.

It would be a great loss to you if you just quit.

Thanks for the advice. I will watch. I am just in a mode right now where dp has sort of taken over my life for the moment, and that is really unhealthy. Have to draw back a bit to get back into myself. It happens every so often. Still trying to learn the fine art of balance. This place has quite a hold on me. It has cast a spell. (lol)

What is with the warning? How did I do that? Must have pressed something wrong.

Right now, I have started waking up between 2 and 3 and so that is why I am here. Hoping to be able to get sleepy again.

Message edited by author 2007-05-18 03:22:53.

Delta_6

Canon EOS-7D

05/18/2007 03:27:38 AM · #24

Not to hijack, but I notice that you and I have the same camera Junie, as well as being in the same boat.