I am a photographer. I have lab fees to print portraits and I am not sure what category that goes under as a business expense?

You can include your lab fees as an "Other Miscellaneous Expense".

In your schedule C:

1. When you get to the screen that asks "What kind of expenses did you have for <your business>?", choose the drop-down for "Less common expenses" and select "Other miscellaneous expenses"
2. Click "Continue"
3. Scroll down to Expenses; find "Other miscellaneous expenses"; click on the blue Start button
4. Enter a description such as "Lab fees" and enter the expense