New Toy - TS (GSO) RC12 with Backplate / Focuser mods

[derrickf]

I ordered a 12" GSO RC from Teleskop Service about 7 weeks ago; I ordered their modified backplate and heavy duty  R&P focuser. The backplate and mirror cell were sent  away to the TS machine shop for the mods which took about 5 weeks.

Big box and a smaller one with accessories arrived today

Pretty securely double boxed for shipping:

The focuser was in the accessories box with the shroud and a few other bits

No broken bits :grin:

The backplate

Focuser attached:

Generally the construction looks pretty good and everything seems to be in order. The focuser was not quite collimated but a few minutes with a Howie Glatter laser and a couple of Allen keys to adjust the collimation ring fixed that. If it ever stops raining long enough for me to carry it across the garden,  I'll post some additional pics when I have got it set up on the Mesu 200 in the observatory

Looking at he weather forecast it looks like it may be a while until first light :-(

Derrick

[laudropb]

Very nice looking scope. I hope the weather improves soon and allows you to get a first light.

[JamesF]

That looks rather nice

James

[MattJenko]

I think this is known as living the dream. Great choice of mount/scope and top of my "one of these days" lists!

[xtreemchaos]

nice scope mate, work of art,hope you get clear skys so you can get firstlight all the best charl.

[cotterless45]

Cloud bringer !

[JamesF]

I think this is known as living the dream. Great choice of mount/scope and top of my "one of these days" lists!

"They're always telling me to live my dreams. But I don't want to be naked in an exam I haven't revised for..."

James

[derrickf]

Thanks for the comments all. It certainly does look the d's bs especially now it is mounted -see photos below.

I'll be really interested to see if the mods to the mirror cell and backplate have solved the well documented collimation stability  problems that affected earlier versions of this model.

For those with short memories the strange looking stuff in the top right corner of one of the photos below is blue sky

Derrick

[BlueAstra]

I have the 10" version. You may be interested in my thread where I described the installation. I changed my focuser to a R&P Feathertouch since the supplied Crayford slipped a little at zenith. I don't use the secondary cover, frightened it might fall off and hit the primary! Either that or I'll start an imaging run and forget to take it off. Is that an elasticated end cover?

http://stargazerslounge.com/topic/218952-altair-rc250-tt/

[derrickf]

Thanks, I read your thread on the 10" whilst I was making up my mind whether to buy the 12" or not - real life experience counts for a  lot.

My OTA has had extensive rework of the mirror cell and backplate including replacement of the stock focuser with a heavy duty R&P similar to the FT.

Now that you have had yours for a while, is your impression of it still favourable?

Derrick

[algady]

Congratulations. Very nice setup.

[laser_jock99]

Looks nice- not at all envious......

[ollypenrice]

Any imager not following this thread must have a problem, either psychological or, more probably, financial! (I have both but it won't stop me.)

Looking forward very much indeed to more news and very best of luck for the commissioning.

I'm impressed and very optimistic. Well done that man!

Olly

[triton1]

No nor am I

[derrickf]

First light - seeing was pretty awful, a lot of moisture in the  atmosphere and the moon was close to full but I could see the stars so here goes. Other than a small tweak to the collimation of the focuser adapter this image was produced with the scope out of the box. Some collimation needed but not a bad start, I'm pretty happy that I can make the needed improvement to the collimation without too much drama - M76: stack of 7 x 600s (no flats so a few dust bunnies are visible) other than dark subtraction,  processing was just a quick stretch in PI.

Atik 383L + EFW2 (Luminance only for this image) Atik OAG and Lodestar2 on Mesu 200

Regards

Derrick

[BlueAstra]

Thanks, I read your thread on the 10" whilst I was making up my mind whether to buy the 12" or not - real life experience counts for a  lot.

 

My OTA has had extensive rework of the mirror cell and backplate including replacement of the stock focuser with a heavy duty R&P similar to the FT.

 

Now that you have had yours for a while, is your impression of it still favourable?

 

Derrick

I like it very much. I've actually never collimated it since delivery. I assume it must need it but I'm still trying to get my head around the best way to do it. I don't want to make it worse! What method do you intend to use? I have a laser collimator, but only used it to align the focuser when I changed it. At the time I also fitted the focuser tilt ring, so the laser was useful to get the axis tilt back to where it was before fitting the new focuser. The stock Crayford struggled under my 3kg imaging load, the FT R&P is much better. I'm thinking of trying a focal reducer to speed it up a bit, but I do like the magnification of the basic system. The weather has been terrible in my area for what seems like the past year, so actually not had a lot of opportunities to use it. However, here are a few images from the scrapbook:

Graham

[derrickf]

Graham, it  certainly doesn't appear from your images that you have any collimation issues that need attention so, in your shoes, I would not touch it - when I had my RCOS 12.5" it held collimation for more than 3 years without needing attention.

I used a Takahashi Collimation Scope in the past but I no longer have it so I plan to tweak collimation of this scope using a star - it seems close enough that no major movement of either mirror is needed. I may also try the holographic concentric circle adapter for my old Howie Glatter laser if I run into any issues.

I have had reasonable success using the AstroPhysics CCD T67 reducer with 3 different RCs and their reasonably inexpensive so you could try that - be aware though that it will shift the focus point inwards which might mean that you have to remove one of the focuser extension rings from the scope.

Derrick