cooled CCD options - Page 2

gbeal · #21 17-01-2009, 07:19 PM

Quote:

Originally Posted by AlexN

lol... yea.. hence why I bought a QHY8 for $1800

Not quite that much now though, $2450.
So $1800 would even be cheap used, LOL.
Gary

renormalised (Carl) · #22 17-01-2009, 07:39 PM

Quote:

Originally Posted by AlexN

1450's got you very close to a QHY8 (non pro) Theres not enough difference in the QHY8pro to make it worth the extra money you know.. sure regulated temperature, but you can DIY this into the QHY8 for about $40... unless you plan to use if on an SCT with Hyperstar/fastar, the standard QHY8 is a better price:performance option from what I can tell...

ps. congrats - $1450 is a good win!

I'd be stoked... I won $250 a few months back and was happy as!

I wish it was still $1800...they're $2450 now!!. Need another high dollar exchange rate. I was reading about Hyperstar....spun out way of mounting your camera!!!. I'd be a bit hesitant on pulling out the corrector place to mount the lens!!!

Thanks...I am stoked about the win. I was one number off the big prize...and the number I needed was on the next line!!!!

AlexN · #23 17-01-2009, 07:42 PM

Bah, removing the corrector is easy business.. I'd do it in a second if the hyperstar + conversion kit was 1/2 the price..

renormalised (Carl) · #24 17-01-2009, 08:10 PM

Quote:

Originally Posted by AlexN

Bah, removing the corrector is easy business.. I'd do it in a second if the hyperstar + conversion kit was 1/2 the price..

After seeing the results of the hyperstar lens from various scopes, I've just become an expert corrector plate remover!!!

AlexN · #25 17-01-2009, 08:15 PM

heh.... yeah... getting the horse head with good signal to noise ratios in 30sec subs did it for me... now I just need the funds..

I figure 10 minute subs of the horse should be marvellous at 11" F/1.8

renormalised (Carl) · #26 17-01-2009, 08:37 PM

With that much detail in so little time, 10 min subs and it'll look like it was taken by the Hubble!!!!

Move over Jase, Marcus, Mike, Peter and Co......

Here comes Alex...with Hubble 2

AlexN · #27 17-01-2009, 09:00 PM

lol..

I think im a long way off their level.. you can acquire all the data in the world.. without proper processing the data is useless..

Ps - Woah.... gone waaay off topic.

Alex

renormalised (Carl) · #28 17-01-2009, 09:03 PM

You'll become a processing guru in no time

Not really off topic, just gives Frank something more to think about

jase (Jason) · #29 17-01-2009, 11:02 PM

Frank,
Given the focal lengths you're talking about...worst case a C14 @ F/11 delivering 3910mm F/L...you'll want to be guiding on the same optical axis as the imaging camera. Whether that be in the form of a guide chip on camera (SBIG) or via an OAG is up to you. An OAG will alter your imaging train and as such the F/L. Guide star selection will need to be considered with both solutions. Its not really a issue, but you'll need to plan framing/composition. If you're happy with an OAG, clearly you can choose any CCD camera manufacturer.

AlexN · #30 17-01-2009, 11:24 PM

As a matter of interest, I've been used an OAG a few times (every night I've been out since I got it) and it does give great results.. the only downside is that my guiding camera isn't very sensitive.. I'm about to get my hands on an SBIG ST4 auto guider to give that a go, but failing that working for me, I'll be getting a Starlight Xpress Lodestar - From what I've read it is a very very sensitive camera, being able to detect stars at 9th magnitude with a 60mm guide scope in a 1sec sub... I hope the ST4 can deliver similar results (documentation claims that when used in an 8" SCT it can get to mag 10 in 1 second..) So given I'll primarily be using it in an 11" sct, I hope to be able to find guide stars with relative ease... the downside is that the field of view will be very small indeed... I suppose it cant hurt to try...

In my 102mm refractor using the DBK31 in the OAG I've had good results on star rich targets, and havent really tried anything that is overly sparse... targets like M42/Eta Car and the horse head have been fine with a 1sec exposure...

I think the OAG is a good idea provided your camera is sensitive.. Your QHY5 should be fine with 14" of light gathering power at its disposal

That said, I'd still look at a self guided SBIG...

renormalised (Carl) · #31 17-01-2009, 11:52 PM

An OAG will certainly save you a bit of money when compared to a guidescope, but as has been mentioned, if you can afford a camera with an inbuilt self guiding chip, like a SBIG, then get one. The only downside of "through the optical axis" guiding is the small FoV in a large scope. That's where a fast refractor used as a guidescope is good. You'll get a decent FoV to play around with, so your choice of guide stars is greater.

In the end, your best bet is to go with what you can afford and what you feel you can handle

spearo (Frank) · #32 18-01-2009, 07:28 AM

Thanks everyone,
I suppose that since I already have a QHY5, I could experiment with a pick-off prism OAG in front of the Canon 20Da.

I'm operating at 2 inch opening now (focuser etc) anyone where I could get an OAG that would fit 2inch?

That would get me a sense of what the QHY5 can pick up as guide stars through the main scope.

Where could I get a 2 inch OAG?
thanks
frank