From: Mark Gaffney <markgaffney@me.com>

Date: February 16, 2010 10:34:59 PM MST

To: Astro_IIDC@yahoogroups.com

Subject: agenda..

Milton,

I`ve written myself a brief agenda for next imaging night (maybe tonight..) I believe I have the  polar alignment done. I know you`re unfamiliar with All Star but I `ve followed it`s proceedures to the letter. Collimation hasn`t changed since the colour M 42 shots with the Flea 2 & the Mogg 0.3 FR so maybe it`s alright enough to try again. It may be I`m finding focusing the B/W camera more difficult than the colour one?

So if I do a 3 star, then attempt to line up the finder with the centre of the camera (Scorpion equipped with Mogg 0.3 FR) by shining a spotlight from the direction of the shed onto the small sign on the container. Then I can test with the Astro IIDC reticle whether a star ( slewed to & lined up) will stay centred in the reticle. If all goes OK & with the star focused best I can, I can then slew to M 42 & attempt to find a nebulous area in the finder if not already centred.

My question this time is when is it best to create a dark image? Before or after the imaged exposure? Does it matter when? Also how accurately must the length of exposure (which I have to shut off) match the length of dark image?If I have one dark image of 1 minute will the same DI be removed from each 1 minute frame of the film-supposing I get this far..?

Mark.