Hi! I'm a total noob to pinhole photography and I aim to start my attempt with a simple paint can pinhole camera. The paint can is approx 8 in (20 cm) diameter and about 7.5 in (19 cm) tall (deep?). I will try to shoot 12 x 7 in (30 x 17 cm) paper negs with it. As the "focal length" is set and will be about 8 in / 20 cm, will a .6 or .7 mm pinhole be alright? I tried the Mr. Pinhole thing on the net, and that gave me apertures in the 280-330 region. I have no idea if that will look good or bad... Advice?