yes you should charge them unless you already said you wouldn't. if you said you wouldn't then deal with it, hate yourself in the morning, and move on. along with photography i'm also a musician, audio engineer and video editor along with DVD authoring. yeah i love it all. anyway i have a lot of musician friends and this one singer and guitarist i have known for 9 years needed a song recorded. well, they are FRIENDS but i still charged them. i gave them a killer recording they needed for $100. so i made some money since it took 4 days of hard work with setup and tear down and mixing and mastering. $100 is nothing but i needed to make something. i told them i can do it and i won't charge you full price. if you're cool with $100 you have a song. i also added in, i don't want to charge you guys but i'm so busy with other projects, i need to justify it. they were cool with that. i HATE charging friends and i feel bad taking the money but it's a business. the way i see it, if they didn't want me, they would have paid 3X's that somewhere else probably for less quality.
i know it's hard to charge for your art and it is easy to forget there are people out there who can't do what you do and are willing to pay for it. there are also people out there who do garbage work and are charging for it. i learned awhile ago that if someone doesn't want to use my services, it's their loss. now i have more time to play guitar or be with my wife or play with my dogs. life is too short. their loss.
charge no more than $150 and let them choose maybe 5 shots to keep. if they want them all, charge another $100 or so to release the copyrights OR just give it to them for $150. but you have to set boundaries or they will take advantage. before you know it they will be taking you to a show and to a park and to their practice spot. so now you spent 2 days shooting in 3 areas and are making $150.
steve