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Matthewstewart
07-11-2012, 10:00 PM
So I've been doing stargazing for about 2 years now, I live in a suburban area where light pollution isn't too big a deal and I am currently using a Skywatcher 127 mm Maksutov Cassegrain.

After all this stargazing I now want to start getting into deep sky photography, this is the equipment I'm leaning towards so far and would appreciate if could get people opinions and or criticisms of the list.

Orion SSDS Monochrome Imaging Camera III
Orion 1.25" Filter Wheel LRGB Set
Skywatcher HEQ5 pro
Orion starshoot autoguider

and of course my Maksutov Cassegrain OTA, though I'm thinking of changing that to something more suited maybe. Any suggestions on that would also be much appreciated.

Thanks in advance

Matt

blink138
07-11-2012, 10:43 PM
thats a very hard way to start i reckon!
monochrome imaging is quite a difficult discipline even for someone more seasoned
if you have a dslr i recommend trying that first as you can manage that just with a $40 adapter
pat

blink138
07-11-2012, 10:52 PM
this was one of the very first stacks i done just with a stock 1000d
it was actually one of the very first times i picked up a dslr!
they get better every time
pat

Matthewstewart
08-11-2012, 01:09 AM
I understand the difficulties of Monochrome and have spent a bit of time looking into the technicalities of it, but I am determined and have a lot of time on my hands at the moment.

I would use a DSLR if I had one, the reason I want a specialised CCD is because I want to spend my money on something that will last me a long time and get the best results, instead of getting a DSLR then moving up to a CCD.

Matt

Matthewstewart
08-11-2012, 01:27 AM
Oh and I have done a bit of planetary photography and video stacking before, just no deep space. So I'm not jumping off the deep end too much I hope, but I understand where you are coming from.

Matt

naskies
08-11-2012, 08:22 AM
Your Mak is a bit slower than ideal for photography (at f/11), which means you'd need very long exposures (4x as long as an f/5.6 refractor), and very good tracking & guiding - especially at the 1500 mm focal length.

It's doable but most people (myself included) find it a bit frustrating to spend night after night getting no reasonable data to tiny problems, like having a number slightly off in the guide settings.

Also, the camera you're looking at has a smaller sensor so you'd want a scope with a shorter focal length to fit an entire object (eg nebula) into one frame.

Something like a 60 or 80 mm apo refractor is a popular way for people to start out - and for good reason too!

Matthewstewart
08-11-2012, 02:08 PM
Yeah that's one of the things I was wondering about, thanks for that. Is there anyway to work out what sort of field of view I would be getting with the camera? I also have a 8 Inch f/5.9 dob, would it be worth getting that to GOTO status, and using that instead? Iv'e just never seen goto dobs being used for photography.

Matt

blink138
08-11-2012, 04:51 PM
matt there is a fantastic download called ccd calc
you can put your aperture, f ratio and camera type into the boxes and it will tell you your chip area
pat

Matthewstewart
08-11-2012, 09:00 PM
Ah thanks pat, just what I needed!

Matthewstewart
08-11-2012, 09:41 PM
So I think I have a solution for my problem, i just have to get a decent 80mm f/5 refractor as my guidescope. That way i can just switch to the refractor when I need a larger field of view or having problems with my Mak. Hopefully fixing it to my Mak will be no problem?

hows that sounding?

matt

blink138
08-11-2012, 10:18 PM
get a good 80mm triplet refractor........ get shut of the mak!
thats what my brother done and has never looked back
pat

Matthewstewart
08-11-2012, 10:26 PM
@Dave "Your Mak is a bit slower than ideal for photography (at f/11), which means you'd need very long exposures (4x as long as an f/5.6 refractor)" I was looking into this and apparently it's a myth? http://www.stanmooreastro.com/f_ratio_myth.htm

Matt

Matthewstewart
08-11-2012, 10:36 PM
@ Pat

Unfortunately a triplet seems to be out of my price range, I can't find any cheaper than $2,400. I am thinking of a Bintel GSO RCA-200 f/8 Astrograph though.

Matt

naskies
09-11-2012, 12:46 AM
It's the same maths - it's just as much of a myth to say that f ratios don't matter. The article you linked to assumes you keep the aperture constant and have an unlimited detector (CCD) size.

Neither is true in your case - you're choosing a scope, thus also choosing your aperture. Furthermore, the image sensor doesn't change size - so when the f ratio increases, your framing changes.

If you keep the framing (ie focal length) and sensor size constant - such as to fit the Orion Nebula into the whole frame - then f ratio matters because it inversely correlates with aperture.

Matthewstewart
09-11-2012, 01:18 AM
Yes I understand what you're saying now, in what you originally said it sounded like you were saying larger f/ratio out right means longer exposure times needed, which is only the case with film photography according to what I linked. My mistake.

Matthewstewart
09-11-2012, 01:40 AM
so this is what I'm leaning towards now for my CCD and imaging scope;

Bintel GSO RCA-200 f/8 Astrograph
Orion Starshoot Pro V2 Deep Space Colour Imager

now thinking of the colour imager, just because I can't find a monochrome within my price range that will give me a decent FOV with that scope ( I've heard its great for deep space photography and its got a good price as well). I could also go for a similarly priced refractor and get the monochrome (because then it would have a decent field of view) but I'm not sure of how good a refractor I could get for $1000. I'll probably end up going with the monochrome/refractor set up just because monochrome photography is what I want to be doing in the long run.

I actually have no idea :mad2:, I think I'm having a bit of an information overload now. I'll just have to let all this new info settle in my head over a few days then make my decision. Thank you both for the help so far.