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Frustrated and confused


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Help I am totally frustrated and confused of the mine field that is astrophotography. I've done some with hints and tips from the guides in the sky at night mag, but still I am confused. The kit im using is Celestron nexstar 6se scope on mount it comes with, Canon 1100d dslr and a Barlow t- adaptor 1 1/4 with t-ring. I've been looking into getting a CCD and the one I've looked at is the Orion starshoot g3 colour , Firstly is my current set up any good and is the CCD I mentioned any good for my scope ? What I'm after doing is DSO'S. Any advice will greatly appreciated.

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Not great for DSOs. Camera is fine. Scope pretty much needs a focal reducer for deep-sky imaging (and I'm assuming a reducer can be had for the 6se). Mount isn't stable enough and is alt-az, you need equatorial for DSO imaging.

The scope and mount are much better for planetary, where an alt-az mount is OK because exposures are short, and the long focal length becomes a good thing. But the DSLR isn't the best for planetary imaging, a webcam or a specialist planetary camera would be better.

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Thanks, I was kinda thinking my mount wasn't any good for DSO'S, but deep down I was hoping I could still use it ( oh well shopping it is then ). I think I can get a focal reducer for my scope, I'll have to do a bit of digging around as I'm sure I've seen one advertised somewhere... again many thanks for your help.

Happy Gazing.

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Another recommendation here for 'Making Every Photon Count' - It really is an imagers bible for DSO imagining. Read it ................ twice or even more .............. before deciding how to spend your cash. You will then have a better idea of what you need and why.

You say that you are getting frustrated and thinking of buying a CCD camera. Your DSLR isn't the weak link in your set up, for DSO imaging it's going to be the mount. I recommend that the HEQ5 is a good starting point for DSO's, but others recommend less. You can pick up a second hand HEQ5 off ABS for about £450.

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Sara and Cantab are absolutely right - the mount is the real weak-point here. For long exposure seep sky imaging you must use an equatorial mount. Whilst you telescope would not be the first choice for deep sky imaging, with a focal reducer and guiding an equatorial mount it would capture some great images of planetary nebulae, galaxies and globular clusters as well as zooming in for close-up of specific regions of emission nebulae. Long- term though, a shorter focal length telescope should be on your shopping list. For now, concentrate on the all important mount.

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U can still give DSOs a go before u get a mount, I have the exact setup and I have an ok pic of Orion neb from lots of 15s subs stacked so u can get sum decent pics of the brighter DSOs but u are very limited. I have myself just brought a reducer but it does add vignetting to the pics and u will also need to buy spacers and 2" adapter to get the required 105mm distance from sensor to reducer.plus before spending loads of money on a new mount it can give u an insight to post processing as well to see if u still want to do DSOs

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I thought you might like to see the difference in tracking with an alt/az and an equatorial, so you can see why yours isn't the best. But some have got some cracking planetary images with your set-up, so don't give up! Sort out a cheap webcam for imaging, to start with (there are tutorials on the web on how to do that for certain cams) and have a go.

http://www.astrotx.com/Field%20Rotation.htm

Alexxx

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So if you buy a heq5 mount, can you use it with any telescope? I also have a celestron 8se and everything else necessary for taking pictures, a Webcam and a dslr and I am really new to this but I have been reading a lot so eventually, I would like to either buy a wedge or a decent mount but would the heq5 work with celestron nexstar telescope or others that I may want to buy in the future? Thanks.

Sent from my GT-N7100 using Tapatalk

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You should be okay with an 8se on an HEQ5. I have a C8 XLT, Startravel 70 guide scope with a Starshoot Autoguider camera and a Canon 1100D for my imaging set-up. That all comes in at 9.2 kg. The HEQ5 has an imaging limit of 11kg so you should be okay weight wise.

hth

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At f/10 you can definitely do even faint DSO's - this is my M33 version at f/11.7:

get.jpg

The problem is - you either have to stick to very bright objects where short exposures are still ok on an Alt/Az mount, or (if you want to afford it) - an EQ5 with at least one motor (but I'm not sure how to guide with that mount) - or a HEQ5 (which I have and am very happy about - latest used sale on eBay 667£).

For the above image you will need quite long exposures though (600s). And you will still have to really pull things out in post processing.

The difference with a "fast" Newtonian is quite remarkable. It cuts the exposure time by over 50% (depending on the scope).

Your camera is fine - don't throw your money on a CCD just yet. Learn the ropes first (including post-processing) - I've seen a lot of sub-optimal images from massively expensive kit!! I'd suggest reading a book on DSLR photography by Lodriguss! Helped me a lot!!!

For now, go for globular clusters and M42. Forget about all the extra stuff. Save up for an equatorial mount and go from there!!

Good luck!

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  • 3 weeks later...

Thanks all I've been looking at an eq mount on the celestron website a computerised G5 mount and tripod and the faqs on their website says the dovetail joint on my scope will fit it, so looks like that might be the one. I have one book so far long exposure astrophotography, and I will be getting more once I've moved. I've got some good shots of the moon and The Orion Nebula but nothing fancy, I've managed to get a small but reasonable shot of Jupiter with my DSLR, and soon I should be getting some better shots and something to be proud of..... again thanks everyone for your help it is very much appreciated.

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I think you will find little difference in the max exposure times you can manage on an alt-az mount and on a normal EQ mount which is not autoguided (by normal I mean under 2K!), if you are imaging at a reasonable long focal length like the 6se.

It is also a myth that you can only successfully image bright DSOs on an alt-az. If you can manage 30s or so on 6 or 8 inch scope then all the Messier and many NGC objects are quite doable.

NigelM

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