[Alex Jenyon]

First major piece of advice would be to stop painting random things straight out of your head! Getting perspective, colour theory, texture, form and so on is hard enough when the scene is right there in front of you. Learning them at the same time as inventing the scene in your head is not going to work.

Paint some real things, in the real world. Don't change it. Don't 'make it better' - just paint what you see. Make use of all the study you have been doing of perspective, colour theory and so on, seeing how they work in real life.

Only once you've nailed that (which won't be a quick process) you are in a position to start inventing, changing and subverting reality to make the images that are in your head.

Probably also worth pointing out that what you are showing here are concept paintings or illustrations - not matte paintings. Though not all matte paintings are photo real, you will need to be able to produce images that are in order to be a matte painter.

Hope that helps

AJ