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Giada
2004-Apr-16, 02:17 AM
Hi everyone,

I'm a long-time lurker, first time poster. I'm interested in doing something with CCD astrophotography for my high school physics class, but I have no experience with it at all. I don't own a CCD camera and there is no way I can purchase one, though I do own a telescope (an 8-inch Meade LX200). Are they available for rent at camera shops? Do you have any advice to give a beginner like me regarding taking photos with them? I have experience with film astrophotography, but none whatsoever with CCD. I know enough to understand that astrophotography is vastly different from conventional photography, keeping track of exposure times that work is essential, and that most of the photos I'll be taking won't turn out well, but beyond that, I have to admit I'm pretty ignorant.

Jigsaw
2004-Apr-16, 02:32 AM
I've seen digital cameras for $80. I know that's probably not real helpful, but the point is, don't think you need to be using some $1,000 state-of-the-art baby. Prices are coming down fast. And lots of people do astrophotography with Best Buy digital cameras.

http://groups.yahoo.com/group/digital_astro/
http://www.fvastro.org/articles/digital/

dakini
2004-Apr-16, 02:37 AM
i did a little astrophotography for a class project and i'm thinking of makign it a hobby... but i used a film camera so i'm not much help, sorry.
i recall reading about using digital cameras though and here are some links that i found while looking...

http://www.covingtoninnovations.com/astro/digital.html
http://skyandtelescope.com/howto/ <--the astrophotography stuff is at the bottom.

those will tell you what kind of camera is necessary and some basics on how to get started...

Argos
2004-Apr-16, 12:54 PM
Welcome to the board.

Here´s a good site on digital imaging (not exactly astronomy-oriented, but features useful info).

http://micro.magnet.fsu.edu/primer/digitalimaging/concepts/concepts.html

And here´s a page on the CCD anatomy.

http://micro.magnet.fsu.edu/primer/digitalimaging/concepts/ccdanatomy.html

Giada
2004-Apr-16, 09:50 PM
Thanks for the information. I'll definitely look into digital photography.

aurora
2004-Apr-16, 10:50 PM
Another way to get started cheaply is with a Web cam.

Do some searching on the web, and you should find articles about connecting a web cam to a telescope, and examples of images that people took.

tngolfplayer
2004-Apr-17, 01:24 AM
I have gotten decent pictures of the sun and moon just by holding the camera up next to a 40 mm eyepiece in my telescope. A lot of people get good photos with little webcams you can buy for under $100. They require some modification, but there are plenty of webpages that describe what o do and how to do t.

Jpax2003
2004-Apr-17, 08:23 AM
It depends on what you want to take pictures of. If you want to capture pictures of the moon then a cheap CCD/CMOS camera would probably suffice. However you would need to jerry-rig the camera to the telescope because most cheap digicams don't have an lens adapter. Some more expensive cameras use adapters and can be mounted to the Telescope.

The main problem with astrophotography is exposure duration. Most digicams do not have extended shutter settings. There is no Bulb or T setting with DCs because the sensor is a charged device running on battery power, so there is a limit to it's capture duration.

Many of the Kodak Digital Cameras I market can take up to a 4 second exposure. More than enough for a moonshot, nominal lightning, and I have no experience with aurora. A few of the Kodak Digital Cameras can take 16 second exposures. There is only one current Kodak Digital Camera that exceeds this. The Kodak EasyShare DX7630 can take an 6.1 Mega Pixel exposure of up to 64 seconds duration. The DX7630 also has 3x optical zoom and an adapter can allow it to accept additional converter lenses. I have not yet tried it with a telescope, but I will inquire about this.

A corallary to exposure duration is earth motion. Any photo will end up with motion blur due to the rotation of the earth. A good motorized equitorial mount for the telescope is a must. A moon shot will often take less than a second's exposure at high magnifications, but planets and starfields will take a longer time. The ability to change exposure value, ISO speed and aperture may be important.

If it is for classroom instruction, you might consider looking at CCD videocams made for telescopes. I remember seeing them at the Orion Telescope website. It can be plugged into a monitor so they can be recoreded and shown to lots of people live.