What telescope should I get?

What telescope should I get?

• What is the best telescope for astrophotography (I want telescopes that can result in clean, clear and crisp photos of not only the nearer objects but also distant faint objects) and also deep-sky viewing? Also what would people regard as the best 3 telescope manufacturing companies? Example: I want a telescope that is equivalent in capability to a Canon EOS 40D in the world of photography and dSLR's.

• Answer:

  Well I am a keen astro photographer, but also have spent almost 45 years as a visual observer using different types of telescopes from Reflectors to Refractors. I know the sky pretty well (I was also lucky enpugh to spend much of my life in the S Hemisphere) and also what I like to image. I cannot speak for others, and you should take my answer as only my opinion, but you said you wanted a telescope that can result in clear and crisp photos. The first thing you need to know is that a Canon EOS 40D, whist an excellent camera will not even approach the sensitivity of an astronomical ccd camera when it comes to clear and crisp astrophotography images. These cameras are not designed for that unless you get it modified by removing the IR Filter (which vrtually blocks all the really interesting Ha wavelenths above 650 nano meters). Remember though this means daylight photography (and your warranty) is out. Secondly the mount is more important than the telescope (or camera). Unless you have a mount which can track stars unguided for 10 minutes or so (with PEC) you will need to autoguide the mount (with a smaller guide telescope) which will enable you to take longer exposures. Stacking short exposures is possible, to avoid noise and improve the signal/noise ratio but it is not the same as a single long exposure. Thirdly you should not decide on the equipment based upon your camera, but in the order of Mount, Telescope, then Camera. You seem to be doing it back to front and I have never heard of anybody asking for advice on a telescope that is equivalent to a camera. Finally you asked what telescope should you get. Assuming you want to do wide field astrophotography with your unmodified Canon, or maybe the Moon and brigter objects (faint objects will not be any good for an unmodified Canon) then I would recommend an Apochromatic refractor with an aperture of 100-125mm as a minimum and a focal length f6 or less. Some people say 80mm is a good size, but this is because these are relatively cheap with a wide angle, however this may be what you want.. As for the best 3 manufacturers of small refractors (80-150mm) and mounts these are Takahashi and Astro-Physics followed quite a way back by TMB. All make excellent astrographs with no abberations. Obviously I am a Takahashi fan. You need to do some research on what you want, because the Canon has an image scale of about 2 arc seconds per pixel, whereas the FSQ-106 from Takahashi can resolve to less than 1 arcsecond and the Canon 40D will not do it justice. But again, you need to take into account the seeing at your location, in many places resolution will never be better than 5 arcseconds, so you need a really dark site with still atmosphere to do better. If you want to take astrophotography seriously with good equipment your budget should be about U$20,000 in total. Some spend as much as US$30-40,000. And let me tell you from experience it takes an awful lot of time, money, effort and frustration to succed. Concentrate on the mount first, a decent mount (Tak or AP)will probably cost about US$6-10,000, the best mount for amateurs, the Paramount by Software Bisque, is about US$13,000. The Takahashi FSQ-106 is about US$7,000 and a decent CCD camera say SBIG is about $8-10,000. Software is also expensive, Maxim DL which I use is about US$500 just for starters, and dont forget the laptop computer because one nights imaging uses up about 1-2 Gigabytes. Never buy a Meade or Celestron as these are pretty poorly made. Good luck.