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Tandum
02-07-2011, 03:26 AM
I finally got my Orion OAG and this is a quick test of the device between clouds. I still see flex issues between the subs, so you get what you pay for I guess. The OAG guide camera mount slops around all over the place and definately needs work, this is obviously where the flex I see is coming from. I have only just managed to get maxim to calibrate through this device tonight. Previously maxim was drawing an hourglass on the screen instead of an L. PHD however calibrated just fine, go figure.

This image is about an hour of Lum in 5 minute subs binned X1 and half that in RGB binned X2. I was more interested in star shape than anything else but thought I'd see more colour in the stars than is showing with these short exposures :( I think binning RGB x2 stuffs the colours on these 8300 cameras. I've read they use a standard pixel during sensor readout so binning would flood that easily.

The other image is S2 data on M16, a mixture of 20 and 30 minute subs, cloud dependent, again looking for star shape but with 30minute subs, rotation should start to sneek in. Stars on the bottom of both are deformed and that is probably focuser droop. There is now a very long chain of stuff hanging out the back of the scope. This OAG added another 50mm to the chain.

No flats on either of these.

Once I had both cameras in focus, finding a guide star is easier than I thought it would be, using a qhy5 guide camera with 2sec subs. Clamping off the OAG and retaining that star is the hard part that I'd like to fix.

I guess the good news is that weight on the mount has now dropped by about 8Kgs. One 5Kg weight, one 60mm guide scope, sbs bar and other mounting gear.

strongmanmike
02-07-2011, 06:42 AM
All looking ok Robin, even if you are not perfectly happy, you got some good results from the evening.

Mike

RickS
02-07-2011, 07:23 AM
Good to see you're making progress, Robin. Shame you can't make it to Ten Chain tonight...

TheDecepticon
02-07-2011, 09:57 AM
I really like the Helix Robin, it seems to have potential! I think if you added some more data, and calibrated the image, it would look great.

Glad to know not to buy the Orion OAG. I'm about to go down this path myself.

Also, I never bin my colour data anymore. I don't like the results.

Tandum
02-07-2011, 12:20 PM
I recon I might be able to tweek it up Mike. Maybe I just expect everything that turns to work like a Tak camera rotator :)

I haven't had a cigarette since last Monday Rick. Trust me, you don't want me at 10Chain tonight :lol:

Gray, I was tossing up between the orion and the starlight. I borrowed Ricks starlight a while ago and it worked well. I went this way so I could remove it when using reducers on the Tak scopes. The SX one would have bolted to my SX wheel and the back distance for the reducers would then be stuffed. Plus the SX one has a C-Thread for the guide camera, this one has a good old T-Thread so the qhy5 goes straight on. It works ok, just needs to be tweeked.

h0ughy
02-07-2011, 12:44 PM
like the test shots - be great to see the long term effort

Hagar
02-07-2011, 12:49 PM
Looking Good Robin. It is sad but seems that everything you buy these days requires modification or add ons to get it to work.
Kep at it you are definitely making headway.

Tandum
02-07-2011, 04:27 PM
So long as everything is stable for Astrofest Dave :)



Tell me about it. I just cut a strip of plastic from the back of a pack of cable clips, pulled the OAG apart and slipped the plastic in between the inner and outer tubes and put it back together. That removed 99% of the slop in the thing. Why they sell them half baked I'll never know :confused2:

I'll try it after dark but it should be way better than it was.