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Oh god the trauma! Tell me if this setup is any good!


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Hi guys

After attempting to ingest hordes of information for what kit I need to get going in astrophotography, I've finally come to what might resemble a conclusion. However I still have questions, hopefully you can help!

The basic set up I'm looking at is:

Mount - Skywatcher HEQ5 Pro GoTo https://www.myastroshop.com.au/products/details.asp?id=MAS-030G

Scope - Skywatcher 200mm Newt. reflector
https://www.myastroshop.com.au/guides/sw600.asp

The one thing I've been reading about is achieving prime focus on the reflector - Is there any other way of achieving this without having to cut the tube up? Do you really need prime focus to have sharp images?

Whats the overall impression of this setup? Any good for a beginner trying to do DSLR AP?

Thanks in advance for any response..


 

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Think of the scope as a replacement for the lens. All lenses have a focus point and so too do telescopes - that's the idea of imaging at prime focus. Also the scope has a larger aperture which is good for gathering light from distant faint objects. But consider the relationship between the aperture and the focal length. This is key to the whole thing.

If you have a focal length of 1000mm and an aperture of 200mm then the focal ratio is f-5 (1000/200). This is ideal for imaging dso's. F-5 will give you images in half the time taken by an f-10 scope. Of course f-10 is very useful for imaging near, bright, objects like planets and moon.

The only slight concern is the weight of the scope, camera, guiding equipment, and other accessories - it all adds up and you may find you're close to the HEQ5 limits. I prefer no more than around 80% of the mount weight limit. For observing only the 200P is fine - and imaging has been done successfully with this combo - but more usually in an obsy.

So do pick a calm, windless night. Other than that you're choices are pretty sound imho. :)

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You could do worse than getting hold of a copy of the book 'Making Every photon Count' available in the book section of the FLO website. It's really something of an imagers bible for DSO's and will really help you understand what you need and why. Read it through twice ........... then again ............ before spending a single penny. It will save you time, effort and money in the long run.

Have you had a look at a field of view calculator (http://www.12dstring.me.uk/fovcalc.php) - Put in your preferred scope and camera combo and have a look at the DSO's that you are thinking of imaging - Does that combo work well for you?

I ask as many start off with a shorter focal length scope such as an ED80 at 500mm. This may sound odd, but many DSO's are huge.

You will also want to be looking at some form of guiding setup soon, as DSO's require long exposures to really get the best out of them. You will place minimum stress on the mount with regards long exposure work with a shorter focal length scope as well.

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Yes, as above but from my own experience I wouldn't exceed 60% of the mount capacity for DSO imaging. I own a HEQ5 pro so limit the full imaging load to 11kg. Above that it struggles.

Enjoy!

Sent from my iPhone using Tapatalk

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I own exactly the setup you are considering - HEQ5 and a SW 200 - I went for the PDS and can achieve focus on camera and visually no bother at all.

Its great for visual and on a calm night - I mean FLAT calm it is great for imaging. BUT - any breeze at all and forget imaging with it.

Given that we are in a windy location (Hebrides)  flat calm nights are a rarity and within 2 weeks I had bought an ED80 for imaging and the HEQ5 barely knows its there.

HTH.

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If it's soley for imaging, I'd seriously concider a small(ish) refractor. the sw 80ED seems a very popular choice (I've gone even smaller with an altair astro 60mm). On the issue of focus, I have a 200p and a canon 1100d and have no trouble with focus..cannot say what other cameras are like though.

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Looks like were all reading that same book? The SW ED80 at present (on recommendations)  would be my choice, should I want to expand into astro photography. 

That said,  Will they still be available to me when the time comes, or will the latest version be out by then? There often comes a time, where something so highly recommended, goes out of stock/fashion, and is superseeded, and sometimes due to cutbacks, becomes an inferior product?  
If I were to go ahead and purchase the SW ED80 now, I would  try it out first, simply beacuse I'm lowering my Aperture, and no hands-on experience with refractors, Just to be certain thats what I need.
Problem is, there are no astronomy shops in my part of Scotland, and the nearest scope I'm aware of is On the West Coast with SB? 
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