Starting up astronomy and have a few questions

[BradB]

I used to do astromony near a decade ago and I have been thinking of picking it up again. I currently have a Celestron 80mm Firstscope EQ but I can not find all of my lenses for it. Instead of buying the parts and peices I have been looking at getting a new telescope, possibly a astromaster 114 az or an astromaster 130 eq. I have been out of the look for so long I was wondering if people could give me some recomendations or advice? I have a moderately low budget, but would like to get something with descent bang for the buck.

[Siguy]

At less than $200, I do recommend the Astromaster 130. It has a nice big aperture and a decent mount. The 114AZ is great for less than $100, but I don't recommend Bird-Jones design particularly. I also would consider an Orion XT4.5 (http://www.telescope.com/control/product/~category_id=reflectors/~pcategory=telescopes/~product_id=09804), if an equatorial mount isn't a necessity.

But by all means, keep your FirstScope 80EQ. It's okay if you lost a few eyepieces, the eyepieces standard with that scope probably weren't that great to begin with. Eyepieces aren't like replacement parts, there are thousands to chose from in no short supply.

[BradB]

Sweet! thanks for the info. Makes me feel better. I did plan on keeping the 80mm. I was looking at a new scope partially due to the cost of replacing several eye pieces, I would nearly pay for a full scope that would come with what I am missing.

[redshifter]

IMO best bang for the buck is a 6 or 8 inch dob. You get enough aperature to see good examples of every type of astronomical object and with some detail and a nice sturdy mount (even more important than good optics) in a package that's very easy to learn on and for not a lot of $. Here are two examples:

http://www.telescope.com/control/product/~category_id=dobsonians/~pcategory=telescopes/~product_id=09185
http://www.telescope.com/control/product/~category_id=dobsonians/~pcategory=telescopes/~product_id=09707

The 8" is a particularly good deal at only $300 and has decent accessories as part of the deal. You could spend a bit more and go with the intelliscope versions, but IMO finding objects yourself is half the fun. Also, you'll now have a smaller 80mm for planetary work, and a nice 'light bucket' for deep sky work.

[BradB]

Thanks Redshifter. I like those orion scopes you and Siguy linked me to. I will now just have to save a bit and make a final decision on what to do. Ended up jerry rigging my celestron since they haven't gotten back to me on a few parts that were missing. Working great and now I just need a light bucket as you call it. I didn't realize how much I had missed doing this until I started back up.

[CollinofAlabama]

Brad,

Have you owned a reflector, and are you a tinkerer? Reflectors, especially fast F/5 reflectors, require frequent tweaking to perform well, unlike your 80mm Firstscope. Besides, no matter WHAT scope you get, you are going to get better performance out of better eyepieces, period.

If you ARE a tinkerer, I agree that nothing will beat a good old newtonian reflector, inch for inch. If you are NOT a tinkerer, and just wanna get out there and look, I recommend getting some better eyepieces and saving your money to get a bigger Maksutov or ED refractor.

For eyepieces, I recommend the Burgess Optical/TMB Planetaries on the high powered end (available at a number of dealers), the Hyperion (or Orion Stratus) 24mm on the low powered end (especially in your Firstscope 80) and probably the 15mm Antares Elite Plossl in the middle (cheapest from Agena). These ep's will perform VERY well in your Firstscope, a 4" ED refractor, or a 6" reflector, for sure.

Check out this site ...

http://www.davidpaulgreen.com/tec.html

to put any possible eyepiece you might want to buy and determine how it will perform in your scope (or some other scope you're thinking of getting) You can replicate these formulas in Excel or some other spreadsheet, btw.

Good luck,

CDS

[redshifter]

By 'tinkering' do you mean collimation? My XT10 seems to hold collimation well, and usually only requires slight adjustment of the primary before each observing session.

[Siguy]

Reflectors, refractors, catadioptrics, it's a matter of personal preference. I think that most modern reflectors hold collimation well enough to only need it once in a while. The little collimation necessary is totally worth the extra aperture. Sure, a good Mak or apo will have a sharper image than a reflector of the same aperture, but it isn't going to be of the same aperture for the same price. For the price of a nice 200mm reflector, you get an 80mm apo. Aperture always wins, and the reflector is going to have more resolving power no matter what with the five inch difference. Sure, small apos are really nice, and wish I had one myself, but they really don't have the versatility and bang for the buck of a nice mid size reflector.

I would suggest an apochromatic refractor if his primary interests were in astrophotography, planetary, and portability, but he mentioned "bang for the buck" and he also already has a small refractor.

[CollinofAlabama]

Siguy,

Your blanket statement on peformance does not jibe with my experience. Although a well collimated, thermally stable 12" refractor will always beat an 80mm ED/APO, if it's not well collimated, well, it can't. I've extensively used a friend's 12.5" F/4.8 dob and my 80mm ED refractor (and his own 120mm ED refractor), and can say unequivocally that, unless his dob was well collimated (mostly determined by the amount of tinkering he did, and even then sometimes to no avail), then the dob could NOT produce pinpoint stars. It also can't do this on cold nights when the temperature required about 2 hours of cooling time before the mirror had stabilized (by which time, we southerners had had enough freezing cold, and enjoyed the night sky with our refractors that exhibited no such problems, and were ready to head back to our respective warm beds).

Under ideal conditions, a 12" newtonian will nearly always outperform a sub 6" ED refractor, but in practical night to night use, it's light gathering advantages might not show up given the above factors. And Brad's own disposition to tinker with collimation and his own willingness to prepare a mirror for thermal stability are much more important factors than aperture alone. Reality always trumps theory. Brad's reality is for his own experience to decide, and no one else's.

Good luck, Brad

[RickJ]

Must be a poor mirror in the dob or some mechanical problem that prevents good collimation. There's a ton of stuff I've seen in my 10" Newtonian I've never been able to pull through with a friends 5" AP APO and its very high quality. Globulars show many times the stars in the Newtonian. The Newtonian sees far more faint galaxies and more detail in those they both see. Yes the background is darker in the APO and contrast in what it does see, higher. This is a look some prefer. That doesn't mean they see more however.

I've never seen a night the Newtonian didn't equal the AP on planetary detail and many nights it beats it with ease. No matter how many times I tried I never saw detail on Ganymede in the 5". It shows easily in the 10" and sometimes I see hints on IO, he sees a disk on all but that's all.

Yes stars are neater in the 5" but stop the 10" down and its stars tighten up as well. I suspect its due to less light rather than better optics.

Contrast is higher of course in the APO due to the lack of a central obstruction but stop a 12.5" down to 5" off axis and you have no obstruction and an image I can't tell from the 5". Yet you also have the aperture when you want it and lots of bucks left in your wallet.

So I guess if optics are faulty in some respect then yes the APO can do very well with its smaller aperture in comparison to a much larger Newtonian. For some things, typical planetary detail for instance a 5" apo and 8" Newtonian are about equal, central obstruction being the villain here, but when it comes to faint fuzzies the 8" will show far more and at far less cost.

We have club members who prefer the look of the image in an APO or high quality ED. That's fine. I can understand that but even they admit for the bucks the larger Dobs show a lot more.

I collimate my 10" once a year whether it needs it or not. Normally not is the word. Well built scopes hold collimation very well just as Siguy says, even under rather rough transportation conditions. Once I had to take to the ditch to avoid a head on collision with a drunk driver who thought it was a 4 lane highway. We went down into the ditch at 65 mph, up the other side, through the air landing in a grassy area. We crossed that and finally stopped almost sideways across another highway after going down and up the ditch on it. When we got to the viewing site we found some damage (fixable) to electronics but the 10 Newtonian was still in perfect collimation after hitting the roof of the car and slamming back down against the deck of the station wagon we were riding in. If it can hold collimation through that it can hold it through anything short of a tornado!

I'm sorry your Dob experience was so poor. From my experience that isn't typical at all.

Yes I own three refractors, one a 4.1" APO that cost more than my 14" LX200R -- and 6 reflectors including the LX200R. For certain things I like the APO, that's why I got it, but general viewing isn't one of them! For that I still prefer the 10" Newtonian.

Rick