Step 1
Bring up Photoshop and create a document to the size you'd like. Make sure to set the color to RGB mode. We will start by making the stars. Fill the background with black
Step 2
Add some noise. Click Filter-Noise-Add Noise. Change the amount to 400% and the distribution to gaussian.
Step 3
Blur the stars a little, click Filter-Blur-Gaussian Blur. Change the radius to .6px.
Step 4
Add a levels adjustment layer. Click Layer-New Adjustments Layer-Levels. Drag the black slider to the right until you have a number of stars that you like. The benefit of using an adjustment layer, is that it is non-destructive and you can go in and change it later on.
Step 5
Add a new layer. Click Layer-New-Layer. Call it something like 'Red Clouds'. Change your foreground color to a red (I used #a71c28) and the background color to black. Click Filter-Render-Clouds.
Step 6
Lets hide some of these clouds with a layer mask. Click Layer-Layer Mask-Reveal All. Click on the gradient tool and set up a black to white radial gradient (drag from the top right area to the bottom left area) to reveal the stars underneath around the edges. Drop the opacity to 90%.
Step 7
The key to getting the illusion of depth and colors in Photoshop is using lots of layers. We are going to use two more cloud layers to help us. Add a new layer, call it 'Blue Clouds. Change the foreground color to a bright blue and render some more clouds (you can use shortcut 'ctrl, f' to repeat the last filter). Add a layer mask and make the same kind of radial gradient mask as we used in the last step. Change the blend mode to hard light and the opacity to 70%.
Step 8
Add the last cloud layer, call this one 'Purple Clouds'. Render some purple clouds. This time make the mask gradient go from top left to bottom right. Change the blend mode to hard light and keep the opacity at 100%.
Step 9
Next up, I wanted to add more interest to the background so I grabbed a lighting effect image. If you downloaded the images at the beginning of this tutorial, open up the one that's named 'Blue Lights'. Place the image on the top layer. Resize it and move it the the top right area.
Step 10
Click Image->Adjustments->Desaturate (keyboard shortcut, ctrl, shift, u). Change the blend mode to overlay and the opacity to 40%.
Step 11
Open up the image named 'Flames'. Place it on a new layer at the top of the layers palette. Position the flames on the right side of the canvas. Change the blend mode to overlay. Add a layer mask, and change your foreground color to black. Grab a round soft brush at around 50% opacity and begin painting away some of the flames. This is a bit tedious, but try to make it blend nicely, keep it subtle.
Step 12
Open up and place the image called 'Space Debris' on the top layer. Resize it to fit just over the size of the canvas. Press 'ctrl, shift, u' to desaturate it. Add a layer mask and mask a black to white radial gradient from the top right area to the bottom left, just like the clouds. Change the blend mode to color dodge and the opacity to 70%.
Step 13
Open up the image called 'Space Craft'. Extract the space craft from it's background, using some combination of the lasso, magic wand, pen tool, etc. There are numerous ways to do this. Once the background is gone, place the image on the top layer of your document, rename it 'Space Craft'. Resize and position it like below.
Step 14
Create a new layer at the top and call it 'Exhaust 1′. Change your foreground color to white and grab the brush tool. Change the settings to a round soft 30px brush. Click and drag a stroke from the top circle exhaust, just like the image below. If you are like me and can't draw a straight line, then hold down shift as you drag, and use a free transform to rotate it into place afterward.
Step 15
Double click next to the layer name to bring up the layer styles window. Add a color overlay of 70% opacity and #f4d0c6 for the color. For the outer glow change the blend mode to color dodge, the opacity to 90%, the color to #ff65ca, the noise to 10, the size to 51 and the range to 63%. This will give our exhaust a nice glow.
Step 16
Grab the smudge tool (shortcut 'r' on the keyboard). Set the opacity to around 20% and make the brush soft and 60px. Click towards the end of the exhuast and drag to smudge it.
Step 17
Add a layer mask and use a black to white linear gradient to mask a little of the end of the exhaust streak.
Step 18
Copy the first exhaust streak and place a new one into it's own layer and position it on the other pipe, then do it again for the third pipe.
Step 19
I dropped the opacity slightly on the streaks that were further away and re-did the gradient layer mask to help with depth. Also grab the eraser tool (shortcut 'e') and go in and erase some of the exhaust trail that covers the pipe to help with realism.
Step 20
What's the fun of a space scene if you don't add a lens flare? Add a new layer to the top and fill it with black. Then click Filter-Render-Lens Flare. Move it to the top right and use 77 for the brightness and 50-300mm zoom for the type. Change the blend mode of the layer to lighten and the opacity to 95%.
Step 21
I added a levels adjustment layer to the top in order to help with contrast. I also put in a little sci-fi type; and here is my finished product.
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