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| Example of a excellent setup for deep sky astrophotography: nice small telescope over a robust mount and a CCD camera specific to Astrophotography. |
"You are a rare case of the correct equipment right the first choice. Most Astronomers I know do not evolve in astrophotography because they not acquire the correct equipment and spend years insisting on a wrong setup". I friend of mine said to me these days. Of course I got very happy with the comment.
Based on this and on a answer I gave to a user in a internet forom that was very praised, I decided to make a small guide here for those who are interested in acquiring good equipment for deep-sky astrophotography.
- Mount: Always get the most robust possible, at least a CG-5 or a motorized EQ5, and for very small telescopes, like refractors of 80mm or smaller. For larger telescopes, such as reflectors above 150mm or larger refractors, prefer a EQ6. Also prefer the mounts that have autoguiding.
It is important to know that many telescopes sold with mounts have it sized just for observational astronomy or planetary astrophotography. So avoid buying them if you want to shoot galaxies and nebulae. Always prefer to buy separate telescope and mount, because to photograph deep sky, when the assembly manual says it can carry 30 pounds, is good to use a optical tube not weigh more than 10 pounds You should always consider that besides the telescope, you will put the camera and other acessories, like a filter wheel and autoguiding setup, which can add a lot of weight over the mount.
I'm not saing that it's impossible take pictures with larger telescopes over less sized mounts, but it is more difficult and the error rate increases greatly. A small telescope on a sturdy mount will always be better and more appropriate.
- Cameras: At least one DSLR or for a specific cooled CCD for Astrophotography.
- Telescopes: Refractors like small EDs or APOs are the best options for EQ5 and EQ6s. Avoid the achromatics but you can get good results with reflectors of 200mm or greater on bigger mounts.
Telescopes with more aperture are faster (The smaller aperture/focal distance, the better the light gathering), but are harder to get a good focus.
A good option is to buy a good camera lens and use it for astrophotography. Prefer models of fixed focal distance and aperture of F2.8 or more.
I notice that very experienced astrophotographers often use the type-Maktusovic Casegrain Telescope eith 14 inches or more, for fabulous photos of deep sky. But we are talking about another level of astrophotography. These telescopes are almost always used in observatories and mounts that can cost tens of thousands of dollars. Maybe one day I get at this level.
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| A C11 on a CG5 mount is an excellent setup for observation and can give good results with planets and the Moon, but is not suitable for deep sky astrophotography. |
Rodrigo Andolfato
