These are some pictures I would like to recreate eventually (or at least try to) so I would like to know what type of lenses would best suit me. As you can see, dusk and nighttime are my preference.
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Take pictures. Take lots and lots of pictures. Take pictures with the equipment you already have. The
only way to improve as a photographer is to take pictures... lots and lots of pictures. I'm not saying that classes aren't important - they are - but until you actually go out and take lots and lots of pictures using the new skills, you will not improve.
Work with the equipment you already have. It will, no question, limit some of things you would like to do... but figuring out how to work around those limits will make you better photographer. The equipment does not make a good photograph, the photographer makes a good photograph. However, good equipment makes a good photographer better.
So.... become the best photographer you can without going crazy on the equipment. Upgrade when you need to, for sure. But don't go crazy. The most expensive part of a good kit are the lenses. And a good tripod.
You have a tremendous opportunity with your access to Disney. However, very quietly do some research. It is possible that you may not be able to do much with the images you take on Disney property. Your case is a bit different because you are a Disney employee, and your contract may have some clauses that Disney will claim restrict what you can do with photos - even on your days off.
So first, read your contract. Second, if you see a clause that seems to restrict what you can do with photos taken on Disney property, check with a lawyer to see if the clause is legal. Third.... even if the clause isn't legal, decide if it's worth risking your job to fight it.
But first.... take photos... lots and lots of photos. Edit them down to your absolute best and show them around.