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mark RD

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Everything posted by mark RD

  1. Yes it looks that way, Its now a fairly decent scope. I will be looking into a smaller secondary mirror possibly upgrading the focuser and a paint job.
  2. OK an update, I had clear skys here and the chance to test out this little project. I found no major issues with CA and the stars looked consistent across the field of view. The only issue I have found is that the secondary mirror been closer to the primary mirror is noticeable and really needs to be reduced in size. The result is that its a little fussy getting your eye in just the right spot. Overall I am really happy with the result, I was not expecting it to work as well as it did.
  3. Thanks for all your info. There seems to be a lot of miss gudence on the internet about bird-jones and I have most likely fallen victim . That was what I felt regarding the Barlow lens. And this was most likely done to keep the size of the scope down and to play the number games on people who think that high magnification makes a good scope.
  4. Thats a possibility. Or I could just rebuild the original tube with fibreglass resin. As I got a good deal on the mount and scope I can get my money back on the going rate for the mount so its not going to be an expensive experiment. In daylight the scope preforms very well,
  5. Bit of a back story before we get to the juicy bits. I have had a really long break from astronomy and was looking for a reasonable telescope, Ideally a short tube refractor. Well anyway I know they are looked upon as been a pretty poor telescope I ended up buying a Seben Big Boss mainly as the EQ3 style mount looked like it would handle something like a SW 80ED with ease however the mount turned out to be little better then the EQ1 and the so called short tube 6" reflector turned out to be a bird jones at 1400mm. I finally got a break and got a good deal on a BRESSER Messier AR-127L/1200 and scope and a EXOS-2/EQ5 mount. So if you have been paying attention you may have worked out that the mentioned scopes are far from rich field. So here comes the fun part. The Seben big boss has a lens in the focuser. I discovered this could be unscrewed. This got my hopes up. I dropped any eyes in it and bang I could not get it to focus so taking the focuser off I lowered the eye piece by hand undil I found a point where it would focus but sadly not anywhere close to the focuser rang. So I though there is only one thing for it. I removed the mirrors and focuser and got the table sew out and cut 50mm of the primary mirror end. reassembled and it was closer to getting into focus but no cigar. A second attempt of another 50mm and boy it was just half a turn on the focuser short. Today I went for another 50mm cut and we have cloudy skys but I think this time I will have a 6" reflector at F4. with a mount that can handle it no problem. Once I get a chance to get this under stars I will update. Pictures to follow soon.
  6. I was intending on buying a decent 2" diagonal anyway so if that will solve the problem then that is great.
  7. I did look up the parts that come with the scope and everything does appear to be there. I am using a 1.25 diagonal so that would be where the problem is. Besser do offer extension tubes of diffrents lengths but to be honest I have a small lathe and could knock up the parts for way less money. There was a couple of extra eye pieces included and the previous owner claims he had only used it three times. It does look in unused condition so I would guess he had the same problem and gave up on it.
  8. I just bought a Bresser AR127 second hand. And I have a bit of a problem. There is not enough outward travel on the focuser to reach focus on the eye pieces it come with, Or my Meade 4000 series. I have took the lenses out of an old 3X Barlow and used this as a spacer and managed to get it to focus I also had to use a different diagonal as with my spacer the diagonal it come with still will not reach focus.. Surly it did not come out the factory too short or am I missing something obvious?
  9. That is a Seben ET8 mount, Its about the size of a EQ3 but no where near as good. There is a lot of plastic parts inside which really should be metal. and it also uses a 12mm Stainless steel rod similar to the EQ1 mount which is held in place with plastic bushings. The clutch is also made from plastic so you cant really lock it in place too well. I have the same mount and am currently machining the plastic parts with metel parts and to tighter tolerances in the hope to improve the mount a bit. They used to be green but they changed to colour to black. I am not sure if Konus bought up Seben but they also supplied there scopes with the same mount as Seben used to Its payload would be 5Kg going by the big boss scope they used to supply it with but been realistic its nearer to 3.0kg Its barely on par with an EQ2 even though its about the size of an EQ3 Hope this helps.
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