[snaggs]

I have ordered a Tak Sky 90 and p2z. That was my budget, since then I've gone over by ordered the field flattener and camera bibs and bobs.

Now, using a Mamiya 645 on a Sky 90 @ f/4.5 with a p2z @ a periodic error of 8 (+- 4). If I do a drift alignment etc.

How long can I expose the film for unguided given that a 400mm focal length and a period error of 8? Will it be long enough to get an image?

Daniel.