Tip for finding composite horizon
I am working on making composite images and and I have found identifying the horizons and perspective very challenging.
To find the horizon in an image is easy if you have one showing, but what if you dont? I have been shown a technique that works most of the time can show you where the horizon may be.
Here is an image that I will use as the background where the horizon is not shown but you can have a pretty good guess where it is. I want to add a figure into the image so I need to work out where to place him and have his size in relationship to this image.
To find out where a horizon probably is I look for 2 items that I can use as perspective lines and draw on the image. This will give me a crossing point where I believe the horizon to be. I then draw a horizon line to use when placing the composite image.
I use the pen tool with the straight line and rubber band turned on and trace the direction the perspective line is going, where these 2 line cross is where I draw a horizon line by holding down the shift key so that it draws completely straight.
3 images with the background showing the perspective lines and horizon drawn in.
This is the figure I want to use and add into the background image, luckily it has a horizon I can use as a guide to draw it in.
I repeat this process to find the horizon with the whole image that has the part I want and draw the lines on in the same way to find the horizon (in this image of course I have the horizon shown so I use that as the guide to draw my horizon). Then I select and copy the part I want and paste it onto the background image.
Then I place the figure directly onto the horizon line and adjust its size, by holding down shift and dragging in one of the corners retains the perspective of the image when to making it smaller or larger.
There is a lot more to do to clean up the image but that is for another day.
I hope this is understandable and helps you in your compositing work.