New dob questions

Hi,

I bought a DSO 8" from Antler Optics last week and have some questions. Before the questions, the scope is very nice and I can't believe what a value these Chinese/Taiwan dobs are. The Antler version has a 2 speed focuser, rollar bearings, upgraded finder and a fan. I had the scope out last night and I thought it did well considering the poor seeing here. I was able to make out the 5th star and had hints of the 6th star of the trapezium. I looked at Saturn but it was low before I had to bring the scope in although it looked sharp for very brief moments. The contrast on the Orion Nebualue seemed very good though I had no other scope out for comparison.


Now the questions- I was using a 22mm Nagler and a 6.7 UWA and I had to slide them out of the focuser with the focuser at max out travel to get them to come to focus. Is this a common issue? Should I live with it or try to get a shorter focal length mirror? Could this possibly cause the light cone to be cut off as the light enters the bottom of the focuser?

What are others using for counterweights? I have heard that magnets and ankle weights are good? Does anyone know a good source of heavy magnets? I would like to be able to use my Denk binoviewer with this scope.

I noticed one clip which extends over the face of the secondary. Is this typical of these scopes and does it interfere with performace?

The scope seems fairly easy to pick up and carry out in one piece but wondering if anyone has added extra handles?

Has anyone tried replacing the secondary collimation screws with thumb screws and if so where did you get them?

Finally, this scope seems so very user friendly in setup and use. I really like being able to carry it out in one piece and more than that have very much enjoyed sitting down and the comfortable eye position. I have been fickle in buying equipment in the past and have a lot of scopes but have the feeling of selling most of my other scopes and focusing on observing with this scope. I feel like I am going full circle since my first scope was a 6" f/8 dob
25 years ago. If I had bought this scope early on, I could have saved some money but I probably wouldn't have been happy without trying refractors/scts/etc. Has anyone else tried a bunch of different scopes and kept an 8" f/6 dob (or similar) as there main/only scope? Thanks!

Dave Adams

If this was an issue, Anttlers should sell the extension tubes at a very reasonable price. This would allow you to focus without sliding the eyepieces out.

I don't think you would cut off the light cone (vignette).

DBA used to sell those weights and Anttler's may sell those as well since they merged.

Hi Dave,
I bought my 8" Dobsonian a few months ago and these inexpensive scope systems are really fun to use. I had mine up to 400x on Saturn about a week ago. The ring structure looked like it was drawn with a fine-line pen.

For counterbalance, I bought four sets of flat square magnets from the hardware store and lined them with felt. I think these work well with an 8" Dob, I can move them around easily and the felt won't damage the finish. The heaviest eyepiece I use is a 2" 28mm Meade SWA and I can balance it with the magnets. At zenith, I slide the magnets opposite the focuser side for counterbalance.

My back isn't strong enough anymore to carry out even an 8" dob so I keep it assembled in the storeroom and carry it out with a handtruck. I bought one of those $20 ones at Tractor Supply.

In addition to my 8" Dob, I also have an assortment of refractors 4" and smaller. I really don't have a "primary" scope since I use them all rather equally. It depends on what type of targets I want to observe as well as sky conditions. I usually don't pull out my Dob unless I have a good, clean steady sky. Since all my scopes are "grab and go," I sometimes pull out more than one.

David E

I had the same problem with getting my eyepieces to come to focus when I installed a new focuser on my Dob. I have to use the 2 inch extension, kinda expensive, but it does the trick


Dave