You're doing the right thing by seeking information "before" you do anything to start a business. Do note that if your state also taxes personal income, you may find it more helpful to seek professional help in your area, as the tax laws differ state to state.
- Start up costs -- These are cost incurred during the process of starting a business, before the business is actually "open for business". Start up costs are reported/claimed as startup cost in the first year the business is "actually" open for business. It flat out does not matter in what year those startup costs were incurred either. But the main thing is, you can't "claim" your startup costs until the tax year you are actually open for business.
You can claim/deduct a maximum of $5000 or up to the amount of actual taxable profit the business makes in that first first (whichever is lower). Anything after that is amortized (not capitalized) and deducted (not depreciated) over the next 15 years.
Some expenses are not expenses, but are assets. Assets are capitalized and depreciated over time. The period of time over which an asset is depreciated, depends on the classification of that asset. For example, photographic equipment is depreciated over 5 years. Basically, an asset is any item used to "produce" income on a recurring basis. For you that would be things like cameras, lights, stands, enlargers, developing equipment, etc.
So it's important to know the difference between a startup expense, and a business asset.
