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I became interested in astronomy a few years ago and started with a Celestron AstroMaster 70AZ refractor telescope. That seemed nice, and I wanted to upgrade to a go-to telescope that was also more much more powerful, so I bought the 8 inch Celestron Schmidt-Cassegrain.

It's great, but honestly I'm a bit disappointed because the magnification doesn't seem all that much stronger than my 70AZ. I haven't done a side by side comparison. But for example when looking at Saturn, I was expecting to see more than just a white ball with a ring around it - I was able to see that with my 70AZ. I thought I'd see colors, and maybe be able to differentiate between some of the bigger ring bands.

I haven't tried any deep sky objects. I'm using various lenses starting from 30mm down to 6mm.

Am I doing something wrong?

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  • $\begingroup$ Related: Telescope Problems. $\endgroup$ – Mitch Goshorn May 31 '15 at 5:23
  • $\begingroup$ related? barely. $\endgroup$ – guntbert May 31 '15 at 8:30
  • $\begingroup$ The 70AZ has a focal length of 900 mm, while the most popular Celestron eight incher has a focal length of 2032 mm, so with the same mm eyepieces, you should get roughly 2.25 fold the magnification with the larger scope. (Magnification = FLobjective/FLeyepiece) rocketmime.com/astronomy/Telescope/Magnification.html $\endgroup$ – Wayfaring Stranger May 31 '15 at 18:49
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Keep in mind that many of the photos you see with colors are composite images. To differentiate colors try to use some various color filters.

To see bands on Saturn, try using a yellow. This will bring out different details in what you are seeing.

This link provides some more details for using various filters. http://www.telescopes.com/telescopes/howdifferentfilterscanbetteryourviewarticle.cfm

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  • $\begingroup$ Thanks @Schleis, that link (and the whole site, it seems) are really informative. What about making Saturn appear "bigger"? It doesn't seem any bigger using this telescope than it did on my other one. I know I'm using the same eye pieces, but even so, I thought there would be a difference in the size and just overall detail. $\endgroup$ – Mike Willis May 31 '15 at 16:29
  • $\begingroup$ As WS said, you should be getting more than twice the magnification with the same eyepieces, but subjectively this may not be very obvious. To benefit from the highest magnifications you need good seeing conditions to match, especially with regard to atmospheric turbulence. I would expect there to be a much greater difference between the two instruments on dim DSOs than on planets: the 8" aperture can capture more than eight times as many photons as the 70-mm, so should provide access to fainter objects. Many of these are fairly large, so are best viewed with medium- to low-power eyepieces. $\endgroup$ – Odysseus May 31 '15 at 23:25

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