Photoshop Elements 8 blending / air brushing

Question

I am adding a rock formation to a Raytrace I made in architectural software.  I used the eraser tool to blend the rock formation into my picture and it doesn't look bad but I want to improve the way it looks.  The issue I am having is where the rock formation starts and stops in the photo.  I added trees in the background to smoothe transition.  I want it to look like the rock formation is actually in the patio.  Right now it looks like I pasted it in and feathered the edges, which is basically what I did.  The transitions needs to be abrupt but realistic.
Can you advise the proper process for doing something like this.
Thanks in advance

Answer 1

Hi,
Let me start by saying that the best option would be to find or make a rock formation model and render it in the software. Assuming you can't do that, this image presents several problems merging 2d with 3d.
1. First, your 2d pasted image isn't seamless.You should go in and use the clone tool to remove straight lines. Try to make it flow with the rock formation. I'll post an image of this postworked at the end.
2. I used your image and bumped it up to add more rock formation then I masked out what I didn't need. You can use the eraser and erase what you don't need if you prefer. (I tried cloning and it just looked better just using what you had. To be clear, I duplicated your image then moved it up to cover the insert area over the pool area. I removed everything but the rock I wanted to use. I used the move tool to adjust where the formation fell in the image.)
3. The 2d rock formation is casting strong shadows. Either render the image again and try to duplicate the rock shadows or remove the shadows from the rock formation. To remove the shadow, create a blank layer over the rock formation. With the clone tool selected, look in the options bar and check the box that says something like "Use all layers" or "Sample all layers". Change the blank layer's blend mode to "Lighten". Now use the clone tool to remove the shadows. Leave the edges.
4. The 2d rock formation sides are not crisp enough. You can use the clone tool to firm up the edges. I would suggest doing this on a blank layer. Leave the blank layer in Normal blend mode. Try to contour the rock so it looks natural.
5. The 2d rock formation is the wrong tone. It's too light and lacks contrast. Use a levels adjustment layer to try to match contrast and tone. Use the mask to limit the effect to just the rock formation.
6. The 2d rock formation is too detailed when comparing it's texture with the surrounding 3d objects. Use the Smart Blur filter to reduce detail.
Note: You may need to clean it up a little by using the clone tool on a blank layer after running the smart blur filter.
Other items....
1. I would fix the corner around the swimming pool deck tile. (See yellow arrow in the image showing problem areas.)
2. Floating tree. Use the clone tool on a blank layer to copy the tree trunk and lower limbs to the left of the pool furniture. Use move tool and bring it over floating tree. (I cloned some of the brown area around the tree also to firm up around the rock formation.
3. I would firm up by using the clone tool the tree around umbrella. You could get away with through the railing and the side of the house the way it is currently feathered.
4. I also used a levels adjustment layer to make the water fall lighter.
Above shows problem areas that I fixed to show you what can be done. (If your software has the capability to render shadows you might consider doing that. If your software allows you to render out objects with an alpha channel, I would suggest doing that. You could get much better results with the trees if you did that.  Basically, you could render the image with trees and render it with only the trees visible. Sandwich the rock formation between the two renders. Load the alpha channel so you only get trees for the tree render. Either mask out or erase tree trunks and branches you don't want overlapping your rock formation. Note: Although Elements doesn't have a channels palette, you can access one if your software renders one out with the image. To get the alpha channel selection if that's possible, use Selection<Load Selection.)
Above shows the what it could potentially look like postworked as I mention. I just hit the items that really caught my eye and stood out as problems. I think if this was my image. If this was mine, I would also add some more trees or work on the right hand side of the image behind the pool deck...
If possible, add the trees as postwork. X-frog has some free sample models that might work out. (Some of the tree models include a PSD of the models rendered over transparency. It might be worth downloading a couple just for that. I think the Autumn Acer Japanese maple and Basic Sweet Birch and Japan Japanese Walnut would work in your image. I believe each of those include PSD files of the items rendered over transparency that you could use. It says on the site that commercial renders are okay...you just can't resell his models or distribute his models. X-frog goes over the what's okay in the blog if you read through the comments.
Here's a link:
http://www.xfrog.com/2011/01/130-free-xfrogplants-now-available/