Newbie Help!

[imballinger]

I am interested in getting into imaging, I have a Celestron Evoultion 8, and am thinking of getting a ZWO ASI1600mm camera https://www.firstlightoptics.com/zwo-cameras/zwo-asi1600mm-cool-usb-3-mono-camera.html

What else would I need to buy to go with the camera? Would these two be a good combination? and what sort of images would I be expecting to get from these together?

[Joel Shepherd]

That will be a challenging combination to start imaging with. The Evo 8 has a long focal length and therefore has little tolerance for poor polar alignment and anything that causes it to track less than perfectly. The ZWO has relatively small pixels which will only exacerbate any tracking problems you might have. FWIW, I've been imaging for 18 months, recently starting working with an 8" Celestron Schmidt-Cassegrain -- same basic design and focal length as yours -- but with a reducer to shorten the focal length by 30% (making it more tolerant of tracking errors), a decent off-axis guider, a camera with bigger pixels than your ZWO ... and I'm getting not-so-round stars.

I'd suggest looking for a scope with a shorter focal length -- a fast 80mm APO refractor is one option, a smaller Newtonian might be another -- and/or consider starting with lunar or planetary imaging (which needs only very short exposures but lots of them) with the Evolution 8.

[Astralprojection]

Hi there! Thanks for your reply!  We (myself and imballinger) have been trying to make sense of how to get started. While it is all still confusing, we essentially want to be able to adapt the scope to all kinds of astroimaging. In my (our) limited understanding, a reducer, a wedge and an autoguider could help achieve that (along with probably more, which is unknown to us as of yet) with the above camera. But frankly, the question is, what do we need to buy to make that scope perfect for all kinds of imaging? 

 

Many thanks in advance

[happy-kat]

Have a look at the no eq challenge thread, two members use that/similar mount but with refractor or camera and camera lens. You still get to try dso imaging but with within the limitations of your mount while you decide what you want to do. You may already own a dslr and lenses.

link here

[ollypenrice]

There is no scope which is perfect for all kinds of astro imaging. It simply does not exist.

If you read the manufacturers' blurbs you will end up believing that with a wedge and an autoguider and a focal reducer you will have a good scope for deep sky imaging. If you look at the deep sky imaging board, right now, you won't see this combination, or anything like it, represented there. There is a reason for this.

I'll be honest: before thrashing around in the dark and throwing money in all directions you should read up on the basics of astrophotography. You need to understand focal length, focal ratio, chip size, pixel scale, polar alignment and autoguiding. These parameters define what does and does not work. Much of this is highly counter-intuitive. That really is the hurdle you need to overcome. I would start by reading a good introductory text like Making Every Photon Count by Steve Richards. If you buy the best racing bicycle wheels and tyres in the world, and the best Ferrari in the world, and put the best bicycle wheels/tyres on the Ferrari you will have neither a good car nor a good bicycle.

Olly

[imballinger]

8 hours ago, ollypenrice said:

There is no scope which is perfect for all kinds of astro imaging. It simply does not exist.

If you read the manufacturers' blurbs you will end up believing that with a wedge and an autoguider and a focal reducer you will have a good scope for deep sky imaging. If you look at the deep sky imaging board, right now, you won't see this combination, or anything like it, represented there. There is a reason for this.

I'll be honest: before thrashing around in the dark and throwing money in all directions you should read up on the basics of astrophotography. You need to understand focal length, focal ratio, chip size, pixel scale, polar alignment and autoguiding. These parameters define what does and does not work. Much of this is highly counter-intuitive. That really is the hurdle you need to overcome. I would start by reading a good introductory text like Making Every Photon Count by Steve Richards. If you buy the best racing bicycle wheels and tyres in the world, and the best Ferrari in the world, and put the best bicycle wheels/tyres on the Ferrari you will have neither a good car nor a good bicycle.

Olly

That is why we are asking for advice first

[ollypenrice]

4 hours ago, imballinger said:

That is why we are asking for advice first

Sure, and my advice is not to start with the details of the kit but by building up an understanding of the principles of astrophotography. The ones I personally think essential in deep sky imaging I mentioned above. They are...

Focal length, focal ratio, chip size, pixel scale, polar alignment and autoguiding. 

Before thining about kit, get your head thoroughly around what all these mean and imply. Someobody who had most certainly done that when I started out a decade or so ago was Ian King. When I explained that I was struggling with a fork mounted LX200 SCT on a wedge and not really getting anywhere he gave me the advice to start with a small refractor on an autoguided german equatorial mount. That was the advice which got me going. All I can do, hand on heart, is pass it on.

If you already have a fork SCT and are thinking of a wedge, here's the catch: a wedge is a disproportionately expensive item. It costs almost half as much as a fully operational HEQ5, a compact and highly predictable german equatorial mount which will work with a small refractor. If you are a mobile imager rather than observatory based then polar aligning a fork and wedge is far more tricky then a german equatorial. Will you succeed with a fork and wedge? Maybe. Some do, some don't. It's a risk. Will you succeed with a GEM and small refractor? If you stick at it, yes.

No single aspect of astrophotography is difficult but astrophotography is  quite difficult simply because there are so many individual things you need to have working and understood at once. If you minimize the difficulty of each one of those things before you start you'll be doing yourself a favour.

It is well worth the effort though...

Olly

 

[RayD]

3 minutes ago, ollypenrice said:

No single aspect of astrophotography is difficult

Apart from explaining and subsequently quantifying the cost of equipment to the Mrs of course 

[ollypenrice]

Just now, RayD said:

Apart from explaining and subsequently quantifying the cost of equipment to the Mrs of course 

Impossible, I agree - even for me when I earn my keep from it!

But 'buy once' makes life easier...

Olly

[iapa]

On 08/01/2017 at 09:59, ollypenrice said:

No single aspect of astrophotography is difficult but astrophotography is  quite difficult simply because there are so many individual things you need to have working and understood at once. If you minimize the difficulty of each one of those things before you start you'll be doing yourself a favour.

It is well worth the effort though...

Olly

 

I have to wholeheartedly agree with both sentiments, there are multiple ideas to understand and tie together and at the end of the day, even your first out of focus overexposed image feels worth every second of the time.

As suggested 'Making Every Photon Count' is a good first point. Read a chapter an night. Then repeat and ask questions here.

Ultimately, OK, initially, there is also less 'upgrade' expenditure that requires approval from the Finance Director.

 

[tomato]

To the budding astro  imagers in Shropshire, I can only endorse the advice already posted. When I got back into Astro imaging after a twenty year break, I did a lot of research first (principally on SGL) and I purchased Making Every Photon Count.

I ended up buying a short focal length refractor and a substantial Equatorial mount, closely followed by an auto guider scope and camera. I Imaged initially with an existing DSLR, a dedicated CCD camera was the most recent equipment purchase.

I'm  not saying you cannot image with your scope but you will probably enjoy more initial success (and that's important in this game, believe me!) with a different set up.

I'm sure others will disagree and say don't follow the mantra, press on with what you already have, but that's what has worked for me.

Incidentally if you haven't already done so, try attending a meeting of the Shropshire Astronomical Society, my brother who lives in Telford  started out on the Astro imaging hobby 2 years ago and has had lots of support and friendly advice from SAS.