The $64,0000 question!

[Les R]

Ok, my query is a bit of an ambiguous one!

I'm completely unclear what I would need to be looking at to do some Astrophotography. I appreciate that Photos of the moon and planets is relatively straight forward and wouldnt be a problem for most telescopes. From what I can deduce, Fork type mounts - even with a wedge are not the best to use for DS and I expect everything revolves around using an equarorial mount and the actual scope itself is a secondary consideration. (ie without that mount, forget DS)

Now the above is all assumption and guesswork as I just keep seeing different answers! It gets confusing! So rather than keep fumbling online, I thought I could ask direct!

So baring in mind budgetry restraints, what would be recomended - or more to the point, what should I be looking towards? I am looking to buy second hand. (I did almost "buy it now" on an 8" almost new LX90 with loads of extras 2 days ago... but because I was unsure, held back, asked some questions and someone beat me to it 2 minutes after I posted my question on ebay!) - For the record it was all 8 months old and receipts for £2400ish and went for £1150

I keep looking at the Meade and Celestron, but not sure if the (perceived) restrictions would keep me happy for long! Obviously ease of use is important. My old 8" Newtonian was 100% manual on an equatorial mount. I just didnt have a clue what I was doing with it and soon lost interest.

Sorry if this has been answered several times (I have looked), but I'm just so itching to buy something! lol

Cheers

[Jim]

Hi Les

Everyone has to tread there own path on this. There really is no right way. However if I was starting again for Astrophotography it would be a HEQ5, a small refractor 70-100mm max, a DSLR and a webcam/finderscope for the guider. Just look at what some of our members have achieved with similiar setups. So be clear about what you want to do and proceed accordingly. My experience of imaging is that you have to do it to learn it, it will involve countless nights of frustrating equipment problems, but that finally, if you persevere, you will gain the skills to become more successful.

[RobertM]

I agree, get used to something with a short focal length first then you'll know what you're letting yourself in for.

Robert

[Carole]

I agree, I would go for an HEQ5 and small refractor.  The ED80 is much recommended and I bought one because of that, it's an excellent scope, but I suggest getting one with a decent finderscope certainly as a beginner as if your mount does not GO TO the right place you'll be messing around for hours trying to find where you are in the sky.

If you're also wanting to do planetary and observing, you can always mount a second much more powerful scope on the HEQ5. 

(N.B. I started out with a 2nd hand CG5 GT which is slightly cheaper see First Light Optics, and a William Optics Megrez 72 APO and this did me well for a couple of years, but if you think you might want to use a heftier telescope you might need the NEQ6 - a lot more expensive). 

Then once you have your telescope and mount, you'll need all the trimmings, imaging camera, dew heaters, power sources, guide camera, guide scope, guide cables, flatteners etc etc.  Don't want to put you off, but this can be an expensive hobby, forewarned is forearmed. 

Oh and also lots of patience and endurance - big learning curve, but very rewarding when it all comes together. 

Carole

[The Thing]

I did the LX90 thing and now I have an HEQ5 and the scope OTA is de-forked and mounted on that. I should have bought something like that in the first place but unlike you, I didn't ask the right people . I wasted years trying to get the fork mount to do astrophotography but it was a dead horse well and truly flogged that had to be put down...

[MarkS]

Hi Les,

I agree with all the previous comments - go for a refractor (since there are no collimation issues) on an HEQ5 (or maybe an EQ6 if you might eventually buy a heavier scope) and use your DSLR (which I think you already have?)  This will be the cheapest way to get into astro-imaging.   Once you need to do longer exposures (for deep sky stuff) then use a finderscope with webcam plus a laptop.  Once you have the basics of imaging sorted you can decide whether to get an additional scope (with different focal length) or a dedicated astro-camera or indeed both!

Make sure a compatible field-flattener for the refractor exists, for imaging. For instance, the Skywatchers generally have compatible flatteners.

Mark

[Les R]

Hi Les

Everyone has to tread there own path on this. There really is no right way. However if I was starting again for Astrophotography it would be a HEQ5, a small refractor 70-100mm max, a DSLR and a webcam/finderscope for the guider. Just look at what some of our members have achieved with similiar setups. So be clear about what you want to do and proceed accordingly. My experience of imaging is that you have to do it to learn it, it will involve countless nights of frustrating equipment problems, but that finally, if you persevere, you will gain the skills to become more successful.

Im confused with the DSLR / Webcam option!

I was under the impression a DSLR wasnt a good tool to use? I expect thats not true for planets / moon, but for DSO?

OK.... taking on board what youve said, what would you recommend as a telescope - or better still what to avoid? (Cheap ebay seben stuff aside!)

I'm still rather surprised that the meade and celestron stuff is on paper market leading brands, but not really recommended! If the mounts are so poor, how are they so popular - or is it just great marketing?

[Carole]

A DSLR is a good astro camera, but get a Canon as that is the one recommended for astro work.  The only drawback with it is the noise as it is not cooled.  Take a look at some of our images on the gallery.  Several of us have DSLRs.

A cooled CCD is better for noise levels but is far more expensive, but many people go for a DSLR to cut their teeth before spending a lot more money.  There are ways around the noise problem such as a hyperstar or Mark's Tak Epsilon, but these are not for the beginner.

Webcams are used for Moon and planets and you can use a telesocpe with a long focal length/high magnification for this as you are capturing a video (unlike the deep sky imaging when it is done via long exposure).  The video gets stacked in software such as Registax to produce a better result than you would get with a single frame.  Long exposure needs to be guided to keep the tracking as accurate as possible and this is also stacked.

If you decide to go for a DSLR, try to get one that has live view and one that will do long exposures (some of the older models will only do 30secs and that will introduce a further set of problems).  This eventually will need to be modified by removing the IR filter in order to capture better data.

Hope this is a bit clearer.

Carole

[RobertM]

A lot depends on your budget Les.  If you have lots of light pollution then you may well get frustrated with a DSLR very quickly on the other hand it is a 'one shot colour' so captures everything in one go.  There's no doubt that data from a cooled mono camera is a lot easier to deal with but takes more setting up (camera/filter wheel + extra power requirements) in the field.

For uncooled cameras like DSLRs you will need to capture many more subs to help subdue the noise generated by the image sensor.  I think that is what Carole is alluding to by mentioning the Hyperstar and Epsilon as they allow you to capture subs quicker because of their faster optics.

Robert

[Les R]

A DSLR is a good astro camera, but get a Canon as that is the one recommended for astro work.  The only drawback with it is the noise as it is not cooled.  Take a look at some of our images on the gallery.  Several of us have DSLRs.

A cooled CCD is better for noise levels but is far more expensive, but many people go for a DSLR to cut their teeth before spending a lot more money.  There are ways around the noise problem such as a hyperstar or Mark's Tak Epsilon, but these are not for the beginner.

Webcams are used for Moon and planets and you can use a telesocpe with a long focal length/high magnification for this as you are capturing a video (unlike the deep sky imaging when it is done via long exposure).  The video gets stacked in software such as Registax to produce a better result than you would get with a single frame.  Long exposure needs to be guided to keep the tracking as accurate as possible and this is also stacked.

If you decide to go for a DSLR, try to get one that has live view and one that will do long exposures (some of the older models will only do 30secs and that will introduce a further set of problems).  This eventually will need to be modified by removing the IR filter in order to capture better data.

Hope this is a bit clearer.

Carole

Clearer? lol Not really! 

I have 2 canons, a 300D and last year a 550D. Not sure what the maximum is for the 550D? I have seen reference to cooling and whilst I appreciate there is something to it, I don;t understand it. (Its ok.. no explanation needed!) I completely understand why the long exposures are needed and why tracking is necessary, though stacking images is weird. Is this to bring out better whats there - or reduce noise with the stacking software?

So a webcam is no use for anything other than the moon or planets? Is a DSLR ok?

Got to say, I still dont get why Meade and Celestron are so popular if there are much better available (and I assume its just the mount that gets the big criticism from you guys?) Or is it just for photography?


How does this one stand up to scrutiny? (Based on whats been said)

[Ian]

I reckon you're budget is about right.

[The Thing]

So you are sorted for a deep sky camera (you have two already). You really need a refractor for ease of use, I think the one you linked to would get you started but you also need a guide scope and camera if you are going to do deep sky imaging.

A suitable webcam and fittings for planetary imaging can be had from Morgan Computers (SPC880 flashed to SPC900, 1.25" nosepiece and IR/UV filter). This scope would be OK to start with as long as you aren't expecting miracles. No guiding needed for planets but you will need a 4x or 5x powermate (a sort of barlow lens) or the image of the planet will be very small. I use my telescope with two 2x barlow lenses giving a focal length of 8000mm (it's 2000mm to start with). Mars is still less than 100 pixels across on a 640x480 pixel chip. It would be a fat dot on a DSLR image.

What I would concentrate on first, knowing what I do now, is a good mount - an HEQ5 is the only way to go as it will give you options later on e.g. guiding. Concentrate on getting that first, not the scope. The mount can be had for around £500. http://www.ebay.co.uk/itm/SKY-WATCHER-EQ5-PRO-SynScan-Goto-Equatorial-Mount-/270874151373?pt=UK_Telescope_Mounts&hash=item3f115b89cd

Hope that helps,

Duncan

[Carole]

Les, I think you will need an Apochromatic telescope for imaging or you'll get chromatic abberation.  The one attached is an Achromatic. 

Carole

[Les R]

I reckon you're budget is about right.

haha  Very good! 


Oh lawd! I've gone and done it!

During the week I set up some ebay items to snipe using goofbay! I forgot all about it and have just bought a Nexstar 6SE (which retails for approx £950) for £510. OK, I know already its not going to do what I'm hoping eventually to do, but at least I have a toy to play with and at the price I paid, won't lose much if at all when I eventually decide to move on.

Looking on all previous 6SE scopes, they never sell below £600 and this is meant to be in new condition and rarely used. Only the standard stuff and a dew cap.

Has anyone got one of these or have first hand knowledge? I am a bit annoyed I forgot to cancel the bids to be made, but I also think thats a reasonable stopgap so maybe not so bad after all....... unless ya gonna tell me different! lol

[MarkS]

Hi Les,

That Nexstar 6SE scope has excellent reviews as a visual scope - powerful and easily portable.  It would also be good for planetary/lunar imaging with a webcam or similar.

However, for deep sky imaging you'll probably find there's not much room for a camera on the back when imaging objects high in the sky.  Also it will be difficult to balance the scope with the additional weight of the camera. Although it has a guiding port (I believe), the biggest problem is that the mount is Alt-Azimuth instead of Equatorial.  This means that you will suffer from an effect known as field rotation unless you mount it on a wedge angled towards the pols star (which is awkward).  

When I first began imaging, I used a Celestron mount very similar to this.  Planetary imaging was no problem but for deep sky objects it made image acquisition difficult and processing a nightmare.  I think I was lucky that it didn't put me off imaging for ever!

Mark

[Les R]

Hi Les,

That Nexstar 6SE scope has excellent reviews as a visual scope - powerful and easily portable.  It would also be good for planetary/lunar imaging with a webcam or similar.

However, for deep sky imaging you'll probably find there's not much room for a camera on the back when imaging objects high in the sky.  Also it will be difficult to balance the scope with the additional weight of the camera. Although it has a guiding port (I believe), the biggest problem is that the mount is Alt-Azimuth instead of Equatorial.  This means that you will suffer from an effect known as field rotation unless you mount it on a wedge angled towards the pols star (which is awkward).  

When I first began imaging, I used a Celestron mount very similar to this.  Planetary imaging was no problem but for deep sky objects it made image acquisition difficult and processing a nightmare.  I think I was lucky that it didn't put me off imaging for ever!

Mark

lol..... and there was me taking my time and making informed judgments on a purchase! Dunno what quite happened there... I did it over a week ago! Yes I understand what you are saying re equatorial mount and ive seen all the comments re using a wedge so wont even try that. Not quite sure what the limitations will be (apart from the obvious ones already mentioned) and as I alluded, as long as the littlun gets to see stuff without a mountain of hassle, it would probably not be a bad thing.

So apart from the moon and planets..... what can I visually expect to see clearly? I do understand why the need is there for long time exposures for photos, but I'm still unclear if those objects are taken blindly and pieced together on a PC in layers!

Anyway.... I'm quite excited at getting it now.... Just a shame its a way down in Chippenham! And with the littluns football until midday, Im struggling to think when I'll be able to get it. I dont want it posted!

[MarkS]

So apart from the moon and planets..... what can I visually expect to see clearly?

The 6SE is an SCT type of scope and has a high magnification which means it has a much narrower field of view than a refractor.
Visually, the moon and planets will look superb.
Unfortunately the narrow field of view (0.8 degrees) means that a star cluster such as the Pleiades will not fit in the eyepiece.  You will be able to see a piece of the very bright Orion Nebula but it will look grey.  The Dumbbell and Ring Nebulae will look well defined (but grey).
Globular clusters such as M13 will look magnificent through that scope.
Galaxies will look like faint grey fuzzy blobs unless you are viewing from a very dark place in which cases you might even be able to just make out arms.
If you are viewing from somewhere less dark I would definitely recommend a light pollution filter in the eyepiece.

I do understand why the need is there for long time exposures for photos, but I'm still unclear if those objects are taken blindly and pieced together on a PC in layers!

I'm not sure what you mean about taking objects "blindly".  We spend a long time carefully lining up the telescope on our target and making sure the focus is perfect.

If you take one long exposure (say 1 hour long) then you may see the following problems:
1) The CCD pixels start to saturate so parts of the image become patches of bright white.
2) The image will be full of aircraft trails, satellite trails, cosmic ray hits etc.
3) A gust of wind might upset the tracking and you waste a whole hour of data.
4) You might not be perfectly aligned to the pole star so the image frame will gradually rotate during the hour, giving tiny star trails.

It is best to take 12 exposures of 5 minutes and add them together:

If these images line up perfectly then they can be literally added together by the computer.  We call this process "stacking".  However in practice they are added using an algorithm that removes the aircraft trails etc.  These things are easily spotted by the algorithm because they appear in one single image but not in the others.  The other slight problem is that the 12 images may not align exactly so the computer has to align the images before adding them.

So there you have it - a quick guide to stacking!

Mark

[Les R]

The 6SE is an SCT type of scope and has a high magnification which means it has a much narrower field of view than a refractor.
Visually, the moon and planets will look superb.
Unfortunately the narrow field of view (0.8 degrees) means that a star cluster such as the Pleiades will not fit in the eyepiece.  You will be able to see a piece of the very bright Orion Nebula but it will look grey.  The Dumbbell and Ring Nebulae will look well defined (but grey).
Globular clusters such as M13 will look magnificent through that scope.
Galaxies will look like faint grey fuzzy blobs unless you are viewing from a very dark place in which cases you might even be able to just make out arms.
If you are viewing from somewhere less dark I would definitely recommend a light pollution filter in the eyepiece.

OK, that makes sense. I always had the impression that without reasonable magnification, things would just be a mere spot in the viewfinder. I didn't think stuff would fill the viewfinder. So there is no colour anywhere (planets aside) visible and everything is down to filters and Photoshop in those marvelous colour images.

I'm not sure what you mean about taking objects "blindly".  We spend a long time carefully lining up the telescope on our target and making sure the focus is perfect.

If you take one long exposure (say 1 hour long) then you may see the following problems:
1) The CCD pixels start to saturate so parts of the image become patches of bright white.
2) The image will be full of aircraft trails, satellite trails, cosmic ray hits etc.
3) A gust of wind might upset the tracking and you waste a whole hour of data.
4) You might not be perfectly aligned to the pole star so the image frame will gradually rotate during the hour, giving tiny star trails.

It is best to take 12 exposures of 5 minutes and add them together:

If these images line up perfectly then they can be literally added together by the computer.  We call this process "stacking".  However in practice they are added using an algorithm that removes the aircraft trails etc.  These things are easily spotted by the algorithm because they appear in one single image but not in the others.  The other slight problem is that the 12 images may not align exactly so the computer has to align the images before adding them.

So there you have it - a quick guide to stacking!

Mark

Thanks Mark...... so in a briefer description, its purpose is mostly error correction which multiple images can detect, remove and enhance. And what I meant by "blindly" was thinking that images being made of things that were too feint to see properly and only visible with really long exposure on equipment more sensitive than our eyes.

Anyway.... I had a long drive down to Chippenham and back this afternoon to pick it up. See the motor drive working and visually, the optics looked fine. (I thought the lens was marked when I arrived, but it turned out it was just in need of a wipe.) It only came with a 25mm eyepeice the diaganal star and dew guard and t adapter.

The guide scope had been removed /lost. (I have a feeling the guy it secondhand and was just knocking it out! I may be wrong - just had that impression) Anyway - so I would need a guidescope for it I guess and an external power source, since imagine the internal batteries would last long.

[MarkS]

So there is no colour anywhere (planets aside) visible and everything is down to filters and Photoshop in those marvelous colour images.

Not exactly.  The colour really exists but unfortunately the human eye is not sensitive enough to see colour in dim objects.  The camera does not have this problem and images the real colour that is actually there.

There's an easy experiment you can do to prove this - go out into the garden in the dark and you won't see the grass is green or that the flowers have different colours.  Now take a long exposure (probably a few minutes) of the garden - you'll notice that the camera picks up the colour you can't see.

That's just like is for faint nebula and galaxies.  It's an amazing experience to see a grey fuzzy blob in the eyepiece and then take a long exposure of the same thing with a colour camera.  All the colours suddenly spring into life.  It is one of the joys of astro-imaging.

By the way, enjoy your new scope!!

Mark

[Les R]

So there is no colour anywhere (planets aside) visible and everything is down to filters and Photoshop in those marvelous colour images.

Not exactly.  The colour really exists but unfortunately the human eye is not sensitive enough to see colour in dim objects.  The camera does not have this problem and images the real colour that is actually there.

There's an easy experiment you can do to prove this - go out into the garden in the dark and you won't see the grass is green or that the flowers have different colours.  Now take a long exposure (probably a few minutes) of the garden - you'll notice that the camera picks up the colour you can't see.

That's just like is for faint nebula and galaxies.  It's an amazing experience to see a grey fuzzy blob in the eyepiece and then take a long exposure of the same thing with a colour camera.  All the colours suddenly spring into life.  It is one of the joys of astro-imaging.

By the way, enjoy your new scope!!

Mark

I know I didn't say as well as you've explained.... but that was what I meant! ie naked eye cant see the colours but long exposure pulls in more light. (Though I did think filters player a part!)

I need to make up a list of things I need to buy... or more to the point, details of the things so I can search online to buy secondhand.