Telescope Reviews: Rebuild/Upgrade of my old 10" f4.66 newtonian OTA

Reassembled it this avo , lasercollimated it again.

Took advantage of the transmission of some laserbeam through the coating (beam visible at night on the back surface of the mirror, put a paper hole reinforcer on back surface of the mirror at the centre of the mirror's back face --- still waiting for my CatsEye spots to arrive).
Noted that the laser spot was dead centre in this ring when I believed the OTA was collimated. 86% reflectivity (standard Al + SiO2 == > 14% transmissity .... you don't need a spot on the front surface to centre the laser beam if you can see the diminished laserspot on the back face and you can see the centre of the back of the mirror (which I can).

This will do until I am ready to clean the mirrors (there are some finger marks on the edge of the primary , and some adhesive dust on the secondary).

Might knock up a Berry style dob rocker box for the OTA for those nights I don't want to muck about with polar alignment or cart the my Atlux out (weighs heaps , is a chore moving it about .... gotta get that ROR shed done .... SOON !!!!) for when I just to look and star hop.
My old rocker box went to the tip .... the old (standard plywood was very ordinary looking .... will use marine ply if I may an new rocker box).

First light this evening , was very pleased with the appearance of the stars at 100x at just on dark.

The old CG5 is not up to it , needs more counterweights , but was OK for finder alignment and initial star testing (using manual slo-mos .... RA was pretty jurky !

! not good , didn't bother powering up the drives , didn't want to risk frying them).

Next task is to check I can reach focus with the Esyguider and 40D attached to the focusor.
Wasn't game with the CG5 RA lock being a bit dodgey and prone to slipping with just the 2x CG5 counterweights attached and at the end of the CW bar, had to really clamp it's RA lock HARD !!!! , this can't be good for the old CG5.

I don't plan on using the 1O" astrograph on the CG5. Will be put on my Atlux which may need some extra counterweighting ( I need to weigh the OTA with/without the camera and OAG and CC attached , and need to calculate my OTA CoG for proper DEC balancing in both cases ...

The Atlux came with one 3.5kg (7.71 lbs) and One 7kg (15.4 lb) counterweight standard kit - this may prove inadequate).

Nothing for it but take the Atlux down to garage once I am sure I have the right amount of counterweights , to properly test it on the GEM intended for it.

Edited by Ian Robinson (09/29/09 08:07 AM)