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Paradox
12-25-2010, 03:32 AM
So, christmas has seen me gain a telescope, DSLR adaptor, and a motor drive, and I'm looking to (Weather and location of 4 D size batteries permitting) get out and take some photographs sometime in the near future! I imagine a few people on here have had a crack at it in the past, and I'm looking for any tips and tricks you might have, being new to the art of photographing the sky.

I have a few random imaginings floating around my head about taking multiple reasonably long exposures and merging them together in software to get a brighter image of planets, seriously increasing the shutter speed for the moon, and trying to figure out which (if any) galaxies might show up as a curiously shaped blob rather than a dot. Any ideas?

Graystar
12-25-2010, 05:03 AM
The first thing you want to do is to join Cloudy Nights Telescope Reviews at www.cloudynights.com. It is THE forum for all things astronomy, including astrophotography. Thatís where you want to ask your questions. You should be able to find astrophotographers in your area there.

You didnít say what kind of telescope you got. The level of detail youíll see depends on the size and focal length. With a 6Ē scope you should see Jupiterís cloud bands and Saturnís ring system (although it will be a few more years before the rings look really great.) Deep Space Objects (DSOs) require very dark skies, which are becoming harder to find. If you live in or near a city, you will have much trouble seeing anything but the very brightest of DSOs.

The mount matters a great deal in your ability to take long exposures. Although people have made great exposures with inexpensive mounts, where they saved in dollars they reinvested in elbow grease and other modifications to improve accuracy. Ask an astrophotographer if a 1000 GBP mount is good enough for astrophotography and heíll say ďjust barelyĒ. That said, with a good polar alignment you should be able to take exposures of 30 seconds or more before any drift is visible, using an inexpensive mount.

Download Stellarium. Itís a simple planetarium software thatís really well written. In the future youíll probably want to get software designed to produce viewing schedules and such, but for now Stellarium is just fun and will start to teach you about whatís in the sky.
http://stellarium.org/

Also check out Tonightís Sky at http://tonightssky.com/MainPage.php Itís a bit much for you right now, but it canít hurt to look at the kind of stuff youíll be learning. Tonightís Sky is great...you say where you are and what you want to see, and it generates a list of objects along with their location in the sky. You then use the Setting Circles on your mount to find the objects. Or, if you have a GoTo mount you simply give the computer the name of the object and the mount will point the telescope in the correct direction.

http://en.wikipedia.org/wiki/Setting_circles

Like anything worth doing, thereís a learning curve. But if you stick with it and have good skies, youíll be rewarded with an enjoyable hobby. The biggest problem by far is avoiding the Aperture Fever. As far as I know, the infection rate is still 100%. :p

Paradox
12-25-2010, 06:38 AM
Thanks, incredibly helpful post! :D Luckily I live out in the sticks so there isn't a lot of light pollution, tiny bit on one side of the house from a town about 10 miles away but not a lot. Just went through the rigmarole of assembling, balancing, and collimating the bugger. Process itself was very easy, but my word was the instruction manual ambiguous. Collimating I ended up twiddling screws randomly to see what did what and working it out for myself. Still, all nicely set up now, and gives good views of the local flora. Now fingers crossed for good viewing conditions tonight! :)

I'm not entirely new to astronomy, been to a fair few meetings at a local club and have done a lot of observing through binoculars and with friends telescopes, but now I finally have my own I'm looking forward to attempting some photographs. I'm not expecting the Hubble deep field, but I'll enjoy trying anyway. :p