It looks wrong because the A-10 is 3d and the M1A1s are 2d

Hi, Chris! Thanks a lot, M8! Very kind of you! 

Considering how new you are to this editing business it's really outstandingly good work, M8! The image as a whole is quite good, IMHO. You really have an intuitive sense for what makes a good, interesting image. 

It's a bit rough, as we knew it would be at a larger size. That's no surprise. We wanted that so we could better see where things could be polished up a bit. 

Please permit me to offer a couple of suggestions for your consideration, Chris:

1) Choose a high quality background image.  When you start out with one this rough it's almost impossible to smooth it out and still have it look good. A better quality background image would, IMHO, offer an immediate,  100% improvement to this image. Not a very "hi tech" suggestion, is it! However, it is one of the basic things that we all learn somewhere along the way! 

2) If you get a background which is a little rough, you may be able to fix it with one of the various types of blurs the editor offers. I don't know if you editor has "Gaussian Blur" but that can work quite well on the rough areas in low doses. Too much and you'll quickly see what happens, hee, hee! 

3) If you have work to do on the background, do it first. You can also do it later as long as it is still on a separate layer. Once you've merged or flattened things, it's a lot harder to work with. This also gives you the opportunity to see if you can bring the background around to an acceptable level before you invest a lot of time and effort in it.

I think that's enough from me for now, hee, hee! What I'm trying to do is to focus in on what appears to be the biggest single thing rather than throwing a bunch of stuff at you all at once. We'll get around to the other stuff as time goes by. No rush. 

So, just keep makin 'em and postin 'em. You might consider the idea of setting a goal for yourself in your next one to start out with a background image which looks good at 800 pixels wide. Don't forget that you can always crop a piece out of a much larger image. I do that more often than not and most of the guys I know who do composites do that as well.

Keep up the good work! You're on a roll!

Tallyho!
Don

You gots it, Red Ryder! Go get 'em! 

thanks a lot Spitfire!! i'll try to work on the tanks 

thanks sytse much appreciated!! i'll try to fix it up some more!! 

Of course, you need to go the way that seems right to you, Chris, but I've found that what Sytse has suggested to be the best way for me personally. Just seems that you can progress and learn faster that way.