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OSC CCD


dawson

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With the planets very low for the next few years, it might be time to dabble with DSOs. I don't want to get Olly Penrice quality images, just some basic colour images of the brighter DSOs.

The DSLR is handy as it is stand alone, but it takes an age to collect data. I'd like to avoid guiding and just do a load of 30-60 second subs, but capture as much data as possible in that time. I want OSC, none of this filter malarky.

So would a OSC CCD be greatly more sensitive than the DSLR, and if so which cameras do people recommend?

I'd probably starting using it with the C11, but would want it to be able to use with either a longer or short focal length scope.

Thanks for any replies.

Jd

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DSLR is good to start with


 


Forget the C11 for DSO its too long and the FOV too narrow


even I have not attempted DSO with the 11


 


 


usual mantra something like a ED 80 and the DSLR and a flattener will be good to start with


 


and if you have a fettled mount and great PA you might be able to get 2 mins subs (or even longer)- but don't hold your breathe and be prepared to throw out a lot


 


guidng is not that hard and you have a cam you camn guide with the ZWO and a finder


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As Steve says forget the c11, you WILL have to guide with that due to fl. I know I did it and thats what got me into guiding, unless your c11 is fastar/hyperstar that is.

I take images of dsos for my own enjoyment and am not trying to compete and get the best astro image ever taken by an amateur therefore Osc ccd was the ideal for me, rgb is just too time consuming FOR ME (caps just to make sure its obvious that this is my preferrence, in case an rgb imager decides to chip in on this). I use a 314l osc and its great, simples, to capture and process which is good for my remaining braincell. A shorter fl scope is a must if your looking to do unguided though, an ed80 as Steve mentions is the weapon of choice by many but there are lots of good fast small scopes out there

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I'd use a modded canon dlsr rather than spend more money on a smaller chip ccd where your choice of target will be less, m31 fills the chip on a canon lovely for instance, heart neb with a ed80 and a modded canon is a beautiful target and again fills the chip.

Smaller targets can be cropped of course. Guiding isn't hard, I know, I can do it, but very worth while.

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Thanks both.

Like philjay, I just want simple images for personal (and facebook) satisfaction.

I managed M57 recently with lots of 30 second subs (below), and i know this is a brighter object which is why i wanted something more sensitive than the DSLR.

I'm pretty keen not to guide, and quite like framing (size) that these smaller objects appear on the final image with the C11.

But if the consensus is, 30-60 second subs even with a sensitive CCD is pointless, then it is a non-starter.

Jd

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imaging DSO's with DSLR is quite fun, this was my first real one


 


http://i1164.photobucket.com/albums/q577/whysall1/stackngc700012p2_zps87db78c5.jpg


 


they were 5 min subd but lots of less time ones should achieve good results, just need to collect lots :)


 


must say i prefer CCD but to get the best you either have to go Mikes way with a mount and get 5 min ones or guide i think


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That is nice sheila. I'll never be able to get 5 minute unguided subs with the C11 and this mount. I think 60 seconds will be the limit.

Rob, i suspect many of the smaller targets (planetary nebula, galaxies, globular clusters) that i'd be going for only have a relatively small amount of hydrogen alpha so i'm not convinced a modified dslr would greatly improve my "sensitivity". It's a shame no one has done a side by side comparison of a canon 6d and one or more OSC CCDs.

Thanks again.

Jd

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James


As Sheila has pointed out.


30 / 60 second subs with a DSLR will get you some cracking DSO images you just need lots and lots of them.


Some of the best DSO images I have seen were taken by a guy on SGL who lives just up the road from me.


All his images are taken on an unguided rig and they are simply stunning.


The other advantage of shorter subs is you do not loose so much time on scrap subs due to aircraft or the like passing through your target area.


There is nothing more frustrating than finding trails through a 20 min sub :lol:


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nope but bright targets as i said, less sub length just lots of them :)  A modded DSLR as far as i know is not for Ha.  the pic above is from a modified canon 40D, unless


i am misunderstanding your 'modded'?


 


Sheila


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That is nice sheila. I'll never be able to get 5 minute unguided subs with the C11 and this mount. I think 60 seconds will be the limit.

Rob, i suspect many of the smaller targets (planetary nebula, galaxies, globular clusters) that i'd be going for only have a relatively small amount of hydrogen alpha so i'm not convinced a modified dslr would greatly improve my "sensitivity". It's a shame no one has done a side by side comparison of a canon 6d and one or more OSC CCDs.

Thanks again.

Jd

 

James if you scroll back through the history I did a side by side comparison of my Canon 350 and the Atik 314 L

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Guest Kheldar

If you just want images for personal use i'd say continue with what you have - there's no need or point throwing money at if if you're only half interested


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Graham it seems the quantum efficiency of my camera is 50% so there may be less difference in that parameter between my dslr and a cheaper CCD; differences in sensor size and whether cooled or not also need to be factored in. Maybe the 6D is better than i'd thought.

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It looks like a QHY8 has a QE of 60%; i'm not sure the extra 10% gained would offset the additional hassle of having to use the laptop to run the camera, so it seems the 6d is actually quite sensitive and tolerable hassle.

Useful exercise, thank you.

Jd

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Big advantage I noticed was the lack of noise in the CCD images allows more agressive processing compared to the DSLR.


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