With all the clouds over the past weeks I have been modding my scope more and more.
A couple of the major ones are:
- After having a play with NEWT the secondary supplied with the scope is way too large at 50mm. NEWT suggested a 33mm secondary so a call to Bintel and I settled on a 39mm Discovery secondary with a Novak cell and spider. In it went quite easily except the spider is a bit too wide for the tube so I just extended the round threaded bits at the end out of the vanes through the existing holes in the tube and made some plywood blocks to slip over them outside the tube so I could tighten them up without cutting the spider down. This part worked well BUT when I tried to collimate the secondary the Novak setup is a horror!! The three collimating screws are at the top of the secondary cell, combine this with a four vane spider and one of the screws is right under a vane. After much frustration it was aligned and I hope to never have to do it again but I know I will and it will be easier next time.
- The other mod was to use the metal plate most people take off the back of the GS mirror cell as a baffle for the fan. Cut out a 70mm diameter hole, cut out three slots for the collimation screws and mount the fan directly to the plate. Cut down the locking screws that I don't use, so they would hold the plate on the outside of the mirror cell without interferring with the collimation. On it went easily and wait for a clear night.
How did they go? Well Saturday night cleared up beautifully and it was off to Linden. The fan caused no detectable vibrations and the mirror settled down very quickly a quick win. As for the secondary, I had a great time with Saturn and the usual targets, Omega Centuri was a stunner but when I got Jupiter up about midnight I nearly fell over. For the first time I could see festoons without even trying!! The equatorial belts have always been easy but the temperate belts were visible, the GRS was clear, I couldn't believe it.
What are the outcomes? If you have a GS scope run NEWT over it and check the size of your secondary. For me the results have well and truely been worth it.