So this is how I generally go about combining 2 or more photos of the same subject to come up with a composite of the two (not “expansion” but I intend to make a tutorial on that soon).
As far as taking the actual photos it is best to have the camera on a tripod and make sure the model doesn’t move except where needed, or if it is a self portrait and you’ll be going back and forth to the camera that you have a point of reference for where to be for all the photos (mark your spot with a leaf, or rock, or what ever you can find) and that you remember your pose (if you’re on the ground remembering things like where sticks are poking you etc. is helpful, if you’re standing remember feet positions etc.) The point is to try and make sure everything is the same in all the photos except for the element that needs to be added.
For this tutorial I’ll be using one of my “Icarus” photos. Because I use a sheet for the “wings” I have to take separate shots for each arm. Because I was on a stump body placement was easy, I just had to remember foot placement and try and be consistent with my arms.
So here’s the photo I started with of the right wing
Then I opened the photo of the left wing and drug it in. Since the camera didn’t move between shots I don’t have to try and line up the environment. If I had moved the camera for some reason after draging I would put the second layer into transform mode (Ctrl+T), reduce the opacity of the layer (in the layers pallete) to about %50, and try to line the two up.
With the layers in place over eachother I added a layer mask to the second layer (layer 1) so that I could remove and add parts of the second photo.
Then using a black brush (In a layer mask black “masks” the photo, thus erasing it and white is areas that are “un-masked” so the layer it’s attached to shows through, shades of grey are inbetween so they will be partially masked) I masked away the area of the second layer that was covering the right wing in the photo below. The red areas in the photo are areas that are masked (when a layer mask is selected, if you press the “" key it will show masking in shades of red.)
Next, to get the wing shap I masked and un-masked areas. On the right I un-masked (white) the second layer so that it would show through effectively covering up the wing in the photo below and on the left I masked (black) the layer so it would disappear, showing the layer below. For these I used a medium hardness brush just to rough it out (to control this open up the brush settings box by right clicking with a brush) Note: the balck and white in the photo below were just painted on to demonstrate. Unless you have the layer mask selected you will just simply be painting on top of your photo.
Here’s what it looked like afterwards. (please ignore the sliver of an image on the top of the next photos. I think it’s because I used MS paint for the screen shots…)
Next I feathered the brush (%0 hardness) and went with the edge of the brush along the areas where I didn’t want any hard edges (the bottoms of the wings) remebering to use white on the right and black on the left. The I took the opacity of the brush down to %20 and started fading the wings.
I kept working at this making multiple passes to remove more and more in various areas until I was satisfied. (I also ended up adding in images of each of my feet w/o my sandals on, I didn’t want them in the photo but the top of the stump was too sharp to be completely barefoot so I alternated feet to relieve pressure. For these I first selected each of the feet with the rectangular marquee tool and then right clicked and chose “layer via copy” and then drug in those layers so I wouldn’t have to deal with a whole photo just for the feet. I then repeated the same process of masking out certain parts so I just had what I needed.)
In the end here’s what ended up being masked, so the red parts are where the second layer (layer 1) is covered up letting the first photo to show through.
This was a pretty simple one to show the general process. If I were working with 3 or more different images each one above the ”background” image would get a layer mask and I would basically be going back and forth between the diferent layers blocking or revealing certain parts of each. In that case it’s important to remember that if say Layer 3 were un-masked in the top right corner, what ever you did to Layer 2 in that area wouldn’t show up because it can’t bee seen through Layer 3. So it’s just a matter of figuring out what’s blocking what and what needs to be seen through.
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