Seeing the older version now , I remember that one in buy and sell thinkining it could be a handfull . .. May it RIP
It was a bit awkward to setup up and collimation was, well, a total bugger, but the Barry Adcock mirror in it - Peter rates it as "up there with the best".... "exceptional quality".
The real issue with the old scope is that it didnt hold collimation, and I had to shim the primary with paper to stop it moving too much in its cell, but this was introducing astigmatism. The cell itself was poorly ventilated, with literally no ventilation from the bottom. The spider was rusted and impossible to properly adjust. However, I bought the whole rig (and got some goodies including a SkyAtlas 2000) for $600, and it came with a couple of eyepieces which I already had so sold those, recovering about $150 from that price. So effectively I payed $450 for the scope. Now to put that in perspective, a 12.5" mirror from OMI goes for $1650 US.
Congrats on the new scope. As I said to you on Cloudy nights I saw it pre delivery, partly assembled and in pieces at Peter's place and it really is a looker. So much so that I gave a lot of though to doing my 10"/F5.3 the same way. Ultimately, I am a "wood" man and I decided to stick with a wood stain "similar" to my 14" SDM.
I think you need to arrange an observing session with someone who owns a paracorr, either a private session or at a public event.
I have an 18"/F4.5 and a 14"/F4.5, both with premium mirrors and I find the desire to use a paracorr to be a very subjective thing.
In both scopes I use the paracorr with the 31mm Nagler, 20mm and 14mm Pentax XW's and the 17mm Nagler T4. I don't find a need or desire to use it with the 12mm Nagler T4 or with the 5,7 and 10mm Pentax XW's or with the 8.5mm Pentax XF. Most focal lengths of the Vixen LVW eyepieces are very well corrected at edge of field, and also have minimal astigmatism and field curvature and some of them, particularly the shorter focal lengths, may be fine without the paracorr at F4.4.
I can only suggest you try "your" eyepieces in "your" scope and then make a decision from there. The paracorr will definately help with some of your eyepieces but it really is a subjective personal decision at F4.4 IMO as to whether the cost (over $500) is worth it. For instance if you spend 80% of your time observing planetaries and galaxies at high power you may not need it. If you spend 80% of your time observing open and globular clusters and nebulae at low to medium power you will probably find a benefit from it.
Thanks all, yep I picked it up on Sunday and we even managed a test drive as the thick broken layer of ex-Melbourne Cloud magically cleared.
Upon arriving, Peter gave a thorough tutorial on assembly and disassembly of the scope, how the components work etc - basically he demonstrated it, then had me do it. I have to say, the new scope takes literally 1-2 minutes to assemble and tear down, while the old version was a frustrating, especially when it came to attaching the UTA, having to wrestle with it to fit it onto the poles then tightening up several screws. But with the new scope, it just slips on, a flick of the clamp and that's it.
One thing that really stood out for me is the collimation of the secondary. Now, the secondary mirror *used* to be the bane of my existance, fiddling with those bloody screws and tools only to get it moving in random directions. Now, it can be accomplished in exactly 0 seconds using the ultra smooth hand nobs and laser collimator. Primary collimation is just as easy using the barlow attachment on the laser. That Astrosystems laser is a beautiful thing. Goodbye flashlight and squinting thru the cheshire in the middle of the night
Peter suggested we try the scope, but it was quite cloudy so I was skeptical, but it actually cleared up quite nicely. So we set up the scope in the field - to be greeted by horror seeing and rapid onset of Dew. Peter did explain that seeing in that area is often poor. However, the moon looked good, even if seen from the bottom of a swimming pool and could immediately pick out 2 Plato Craterlets with an 18mm eyepiece.
We also tried a Paracorr on the Jewel Box, and bloody hell what a difference! Granted, we used a 35mm Panoptic, so coma was much more than what I'll be seeing with my 22mm and shorter LVW's but the Paracorr dramatically cleaned up the edge of the field.
Then, we packed the scope in the car as it was getting late and went inside for a bite. Then I was on my way, running into deck of Melbourne cloud as I hit Wallan and even some rain by the time I was on the Monash. Gee, who didn't see that one coming
Many thanks to Peter and Kim for their hospitality and to Peter for creating this masterpiece!
Little Gem indeed! I cannot be more pleased. Peter even put on an entirely new Telrad even though my old one was working properly, but he didn't let it go on due to the velcro and marks all over it... I guess that just shows his commitment to customer service and his immaculate attention to detail. Now I have 2 perfectly functioning telrads
Forecast for a clear Saturday night still looking good.... Full moon but I don't give a donkey's last crap!!
Last edited by pgc hunter; 29-04-2010 at 03:53 PM.
Just lovely Sab. Between you and Erick you've got me thinking about what I might do to my 12" GSO!
You should send pics to Barry Adcock, sure he would be chuffed to see one of his creations getting a new lease of life,
Im a little surprised to see an 18pt cell for a 12" mirror. My 15" sits on a 9pt.
Hi Geoff,
I can give you a little insight into the 18 point cell. When Peter and I set the design specs for my 14" scope at the beginning of last year, I requested a "stainless steel cable mirror sling" system. The reason for this is that I need to rinse my mirror about 4 times per year because I live right on the salt water. The stainless cable/velcro system makes it much easier to get the mirror in and out of the scope than the traditional kevlar sling/double sided tape system, which is what my 18" Obsession has. In addition my 14" Zambuto mirror is only 34mm (1.33") thick, to aid cooling. Peter decided to avoid any possible risk (however low) of having mirror cell induced astigmatism, to use an 18 point mirror cell. Basically my 14" was the first of the small scopes with an 18 point mirror cell and stainless cable sling. You will notice SAB's scope also has the stainless steel cable mirror sling system.
As a result of how well this works and how easy it is to get the mirror in and out of the scope, Peter has decided to use the cable sling system on all future scopes, notwithstanding it makes quite a bit of extra work for him. Why he used the 18 point cell on these 12" scopes with thicker mirrors I don't know, because there is clearly no need for it, moreso having regard to the fact these mirrors are fairly thick. However, I guess it comes back to Peter's motivation which is to build the best possible telescope that he is physically capable of building. Having seen these 12" scopes in the flesh they are clearly "overengineered" for their aperture, but it makes for an exceptionally performing high quality product which is what Peter strives to achieve. My 10" scope will have a 9 point cell with the stainless cable sling.
.. May it RIP 
I thought I saw a few flowers doing the mexican wave as I walked past on the way home ... in the rain 
