Hello, I am considereing buying a pentax 6x7 camera as my first medium format camera and have some questions. I see there are versions which have a metered prism and some without. If I have the unmetered version, can I effectively meter a scene with a hand held meter? Will this be accurate if for the exposure or should I look for a metered prism camera? If anyone has any other suggestions about a decent first medium format camera, I do not want to spend a large amount of money (max maybe $400 for the body). Thankyou.