victor truglio said:
I am trying to decide between a Meade 12" lx90GPS or
a teeter 10" with sky commander and Stevens mirror
Scope will be my main scope and will not be trasported just used at home in my light polluted backyard
I have a 6" mak as a quick view scope as well
I have owned in the neighborhood of 40 scopes in the past 2.5 years, maybe more.
The small scopes just dont show me much.
Anyway for general viewing, no photography, both used, same price both in excellent condition
12" Sct or 10" dob
Thanks
Like you, I have owned a bunch of telescopes over the past 15 years or so, including 5 Starmasters, an AP refractor, Tak FS128, TMB 100/800, etc. but I can't say that I have owned 40 telescopes in 15 years, let alone 2.5!
I also used to own the Teeter dob that I think you are talking about, and I can tell you that it us absolutely superb in every way. Excellent optics, easy to set up, and beautiful to look at. The planetary views in that telescope are amazing, and it doesn't need a Paracorr. I sold it back when I thought that I was getting out of the hobby, and three months later I bought a Nexstar11GPS when I realized that I still wanted to observe, but I wanted to be comfy when observing, and I wanted goto and tracking.
Optics: IMO, optically the SCT gives nothing up to that dob other than fov and perhaps a bit of cooldown time. I am sure that a bench test would show the Stevens mirror superior to the SCT's optics, but to my aging eyes any difference is negligible. Maybe I got lucky, but I find the optics in my SCT to be very good to excellent. This is the second SCT that I have owned in my 15 years in this hobby, and I found that the optics in my NS8i were also very good.
Setup time: I can set my NS11GPS up in about half the time it took to set up the dob when you consider installing 8 truss poles, setting the OTA atop them, then collimating the telescope. With the SCT, I pull the tripod out of the shed and carry it about three feet, put the fork/OTA assembly on the tripod, and tighten three bolts. That's it. I collimated my SCT when it arrived, check it each observing session, but have only had to recollimate it once in the last year.
Cooldown: I use a Lymax Cat Cooler on the SCT and find that I reach ambient within a half hour or so. Keep in mind, however, that I keep the scope in an unheated, uncooled, well ventilated shed next to my observing pad. The Teeter probably cooled down a tad faster when running the boundary layer fans thanks to the open tube and thin primary mirror. My cooling issues down here may be a bit different than yours though.
Observing position: I enjoy sitting behind the SCT to do all of my observing, and I am not on my knees when observing just above the trees like I was with any of the dobs that I have owned. I love the goto because I am a lazy observer who doesn't like to hunt for stuff, and I am lousy at reading a star chart anyway. Oh, I also use a Denkmeier Power x Switch so I can get three magnifications (.66x, 1X and 2x) out of one eyepiece. I find that often I only use my 30mm Vernonscope WF for an entire session.
Dew: the biggest killer for the SCT, IMO. Not really an issue with the dob except on the wettest nights. You will at least need passive prevention, i.e. a dew shield, with the SCT, but I think that most prefer active prevention like a Dew Buster. I just use an Astrozap shield and it keeps me going for as long as I am likely to stay out, which is usually not past 2:00 am.
Sorry to ramble, but since I did own the dob in question, and am now happily using a SCT, I thought that I might be able to offer a different perspective.
As Jon said, however, only you can answer the question as to what type of observing you prefer. If you like knowing that you have optics that are above reproach, and you prefer the simple nudge-nudge style of a dob, you can't go wrong with the Teeter. If you like to have tracking without the need to add a platform or ServoCat, sitting behind the scope to observe, having the ability to do imaging, and still get great views, go with the SCT.
Doug
Midway, FL
