General Rules...
* Here's an interesting one I ran across: for 400 ASA films in a good dark sky, expose no longer than the square of your f/ratio or you'll start to sky fog (your dark sky will go gray). That means with an f/1.8 wide open 50mm lens, 3.5 minutes. Through a telescope like our Orion Short Tube at f/5, that's 25 minutes. Reciprocity failure comes in too, though, so if you're thinking of taking several and stacking, you may save time (but not film $$$) by taking several shorter pictures.
Film Selection...
I've looked at these sites in hopes of getting the best choice before ordering my own films. Don Westergren's site seems to be the most up to date. However, there are yahoo groups for astrophotography and their discussion groups may have anecdotal comments of use too. A good choices for slide film are Fuji Provia 400F, and Kodak Elite Chrome 200 / Ektachrome 200 (same film).
Links...
* Don Westergren's astro film evalution page. Good, ( as of June 2004).
* SkyNews page on modern astrophoto films. An interesting comment made on this page is that modern slide films scan better into digital form than print films.
* Petermann's page on astro films
* B&H Photo in New York is my favorite for getting gray market film at great prices, and other hard to find gizmo's.
* Michael Covington's insights on film for astrophotography, and Robert Reeves' page. Reeves site is excellent, but apparently several years out of date. This may be a big problem as films are coming and (mostly) going at an increasingly rapid rate.
* Jerry Lodriguss' site has incredible photos and many great ideas. This page has a photo-linked index of many of the nicest astro subjects. If you're looking for your next object to nab, this is a great starting location to get a feel for image size, exposure length etc for your equipment.
* Pennington's Primer on astrophotography
* A table of exposures for astro subjects
You can download a free Windows-based image scale calculator with a ton of preset telescopes and CCD camera's which will show you the image and border for each. This is really great! Download CCDcalc here.
Your digital camera probably output jpeg (.jpg) files, like our Dimage 5. Our SBIG ST7 CCD camera outputs .st7 files. For astronomical research purposes, files should be in the FITS format (.FTS). Photoshop has their own format too, although you can import many different formats in the Photoshop. Somewhere along the way, you'll want a program to convert images from one format to another. For the PC, in my browsing so far, the best deal seems to be OmniFormat. It's free, and converts over 75 different formats. You can read about it and download it here.
Our new SBIG ST2000XCM outputs color pictures taken with a single shot. The 1600x1200 pixel detector is arrayed in 2x3 groups of tricolor filtered pixels, giving a color picture of 800x600 color resolution, but 1600x1200 luminance resolution. Use of CCDOPS and other digital processing instruction can be found on the Starizona site.
DCRAW - DC Raw is a software program which will convert the raw output files from over 90 different digital cameras into a variety of formats. I'm still learning about this program, but you can check it out for yourself. My goal would be to use DCRAW to be able to do dark subtractions using our Minolta Dimage 5 camera. Our Minolta will optionally save frames in RAW format, but we need software to be able to read this format and do image manipulation, including addition and subtraction of other frames, in order to do dark subtractions. Read about and download DCRAW here.
Here is a good site describing digital processing with Registax (here is a Registax tutorial) on planetary images.
Kodak has, free digital imaging software which you can download, called EasyShare, for organizing and sharing your digital images..
Registax sometimes has a hard time stacking large numbers of large files (it was originally made for stacking small video frames). You can also do a good job of stacking by hand in Photoshop. Here's a good cookbook how-to for stacking images in Photoshop using layers.
And there is a terrific free program for doing quite a number of image manipulations. In particular, you can assemble a montage from a series of overlapping images in Windows by using Iris.