11 replies to this topic

[Blair]

I had a 6" f/5 Discovery Dob and Orion's 120mm f/8 scope at the same time. I liked the look of Jupiter better in the Dob but then I never used a Violet filter with the refractor. I sold both. The Dob because I did not like the position I had to sit in to use it. The 120mm because it was heavier (on an equatorial mount) than what I wanted to deal with on a regular basis. I now have a 100mm f/6 rich field scope on a AZ-3 mount and am really happy with it. I can go from 15X to 120X which is a good power range. The 120mm OTA will work on the Astroview mount but when looking at the apex of the sky the eyepiece will be very close to the ground (below sitting in a chair to view) if the scope is balanced and there will be a vibration issue at high powers. Hope this helps.

[Stacy]

I have been eyeballing those for awhile. But the mount is a serious consideration. I have my 5” f/9.3 on a CG-5A, which I believe extends a little farther than the Astroview, and still find myself on the ground when looking near zenith. Since it seems planets and the moon are rarely directly overhead, that may not be an issue.

OTOH, I love the views out of the refractor! Not better or worse than a reflector, but different in a good way. I love my reflector as well, but the contrast is better with the unobstructed reflector. At $319 + it’s hard to go wrong.

Since the clouds don’t appear to be going anywhere soon, you may want to hold out for a sale from Orion (although their sales usually apply to their package deals) or check their 2nd’s. Or better yet, check out Astromart. Great deals on refractors appear there often. Don’t waffle though … you gotta be quick! I got my Meade 5” almost new with rings, finder, diagonal & EP for $275. Missed out on a Skywatcher 6” for $250 though.

Good luck!

Stacy

[Trever]

Well since in the last 2 months I have owned an 8 inch Dob and a 6 inch refractor, I can say that it is somewhat easier to carry the refractor tube on my shoulder. It also seems to me that the images are brighter through the refractor. Especially the DSO's....

[SAL]

Kileak: I'm going to weigh in on this discussion because I have owned two versions of the Orion 120mm f8.3, one on the AstroView mount and aluminum tripod, and a second on the SkyView Pro mount and steel tripod. First let’s address quality control issues. Mt first 120 OTA arrived from Orion with fantastic optical performance, (once I collimated the scope). My second version arrived with terrible performance even after collimation (greatly increased false color, color spiking, and distortions near the edge of the field of view). Orion customer service was terrific, and offered to either replace or repair the OTA immediately. I let their repair department test my OTA, and they found there were problems with the focuser. However, it had better Ronchi and star test results than three “new” versions they tested it against, so I elected to keep this OTA with a repaired focuser. The end result is a 120mm f8.3 that actually outperforms my original Orion, which I really loved.

So, why did I upgrade my original AstroView 120 for the SkyView Pro 120? The short answer is the AstroView mount and tripod system. By Orion’s own service tech’s admission, this OTA pushes the AstroView to the edge of its capabilities. I found the AstroView system was usable with this OTA, but focusing at higher magnifications was quite difficult due to mount movement and tripod vibration. There was a large amount of “slop” and free play in the mount. Tightening the adjustment screws reduced this condition, but did not eliminate it. Placing the tripod on grass helped, and I’m told the anti-vibration pads also help a bit. There are web sites that provide suggested tweaks to further decrease AstroView vibration, but this OTA is simply asking a lot from the AstroView system due to its weight. The SkyView Pro mount and steel tripod on the other hand, are a completely different story. This OTA is rock steady on the SkyView Pro system. If I had to assign a numerical comparison, I would say the SkyView Pro is three to four times steadier than then the AstroView for the 120 f8.3 OTA

I have no real experience with reflector telescopes (I’m a refractor enthusiast), so take this into consideration when reading my comments. It is true that at zenith the viewing position is low, but I don’t find it impossible. (The SkyView Pro tripod does give you additional height that helps with this issue). The views are sharp, stars are nice bright pinpoints, and a 120mm worth of aperture is a good amount to see many DSO’s beyond the planets. Fellow astronomer friends of mine have commented on how ridiculously good the views are from the OTA for the price. Is false color evident? Yes, but when properly collimated it is relatively little, and then only shows itself mostly on bright stars like Vega. I do not use a minus violet filter at this point. (Admittedly CA false color does not bother me like it does some folks. I’m sure that if I became accustomed to high-end APO views, it would be more noticeable to me). I have very little cool down time, which is important to me during cold Midwest winters.

My point is that I consider this OTA a fantastic bargain for the price. You certainly can use it with your AstroView system, but will probably need to tweak the tripod and mount to get optimum performance. I wouldn’t let Synta quality control issues scare you away as Orion is one of the most dedicated companies I’ve found when it comes to insuring their customers satisfaction. If you get a bad sample, they will make it right. Hope this post helps make your decision a little easier… (Scott)

[RGM]

I just have to add my 2 cents worth. The mount makes all the difference. I have a Vixen SP eq head on a 4 inch diameter pier. This set up will take any magnification with no vibration. If you use a tripod, modify it the best you can. The only things I have done to the OTA is to take the focuser apart and clean it, and collimate the objective. I use a Lumicon MV filter and just keep it on for everything. I am glad to see all the interest in this telescope. This is a great telscope for the money. Leaves you enough money for eyepieces and filters. Bob