Moon and Planetary Film Photography
Prime focus photos of the moon are relatively easy and a good place to start in astrophotography. Because of the fast shutter speeds, you don't need perfect polar alignment. All that is really needed is a prime focus adapter obtained new for about 30 bucks or less than 20 used, and a T-Ring for your SLR camera that can be obtained at most any camera shop or on the used market for less than 10 bucks. I tried prime focus photos of Jupiter and Saturn. Don't waste your time as the images are way too small. The only useful photo that can be obtained this way is Jupiter and it's moons with the planet overexposed and this would be only if you had at least 1000mm of focal length. For anything else, you will need a tele extension tube. These can also be found used and reasonably priced. They are usually machined aluminum tubes so unless the threads are stripped, not much can be wrong with a used one. New they are cheap also at around $40. I have noticed fewer of thesse on the used market. There are formulas available that explain how to determine the magnification obtained. I have found half way out on the Meade extender and a 7mm epiece work best for me. More extension dims the image requiring a longer exposure time which is further compromised by seeing conditions. I recommend experimenting.
You will want to take careful notes of the picture number, shutter speed, eyepiece used, and the extension on the extension tube. This way you can make sense of them all when you get them back from the photo finisher. Choose your photo lab carefully and I also recommend you choose on that finishes onsite rather than shipping them out so you can work with them otherwise, your photos are processed automatically which can lead to images being off center that were not shot that way. You can find fainter prints missing as computer did not "see" them in the printing process and also negatives being cut in the wrong place. I recommend you have them leave negatives uncut. Film is relatively cheap and finishing is more expensive. For this reason, I feel shooting shorter rolls such as 12 exposures, works best. This way you can take a number of shots, get them processed, then take corrective action. You pay a small amount more for the film this way, however it seems better than paying for 24 to 36 exposures of junk. If I get two or three good shots in each roll, I feel somewhat successful.
I have used both automatic cameras and manual cameras with this method. Since exposures are short, you need not worry about the battery going dead and closing the shutter prematurely as with deep sky shooting. I have had better luck with the Canon FTQL as you would with other "astrocams" as the mirror can be locked up. This prevents one of the sources of vibration that can kill the sharpness of the image. For these shots I found that a cable release not necessary and what may be better is a self timer. By the time that the shutter fires, vibrations from your contact with the camera have had time to subside. You will also want to lock down all the clutches on your mount if so equipped. The Losmandy among otehrs has ability to tighten so that the scope cannot be easily moved by hand, but drive is still engaged. You will want to use a flat field eyepiece inserted into the extension tube such as 5mm-10mm. I have found that my 7mm Nagler worked better than Televue plossls or Celestron Plossls and Kelners for this purpose. I have not tried an orthoscopic ep for projection, but I understand they work well also. The following image was actually taken with afocal ep projection.
Another viable method is to use afocal eyepiece projection. This is using the camera and lens on a tripod that is set up very close to eyepiece. I have obtained some good results this way on the moon. I have not tried it on the planets but others have with decent results. It actually may have some benefits in that the actions from the camera mirror and shutter do not vibrate the telescope optics. You could possibly use a non-SLR camera for this purpose if you can control shutter speed down to the 1/4 second or so that would be needed. If using an SLR, you will probably find it best to use a 50mm lens. You will also want to use a widefield eyepiece that has shorter focal length such as a 7-15mm. If you use a plossl type you will be restricted to 15mm or above. When the exit pupil and opening of the ep gets smaller, you will start to get a sort of vingetting as your seeing the end of the ep with the camera. You will also get this with wide angle camera lenses. You are able to obtain slightly higher f-ratios with this method as the camera may be able to be placed further away from the eyepiece than with a projection tube.
