What Next?

[groberts]

I started my astrophotography journey a couple of years ago, it’s been a steep learning curve but rewarding.  After starting with a Skywatcher 150PL, I purchased a William Optics GT81 which has been a real eye opener and I’ve used exclusively since the end of 2014, together with an AZ-EQ6 mount.

From the start the combination was a real winner – aside from the very good optics of the WO and pleasure of computer guided tracking etc, I have really enjoyed the convenience and speed of the WO for DSOs, which have become my targets of choice when possible.  Notwithstanding, the WO size struggles with smaller DSOs and galaxies and inevitably I now feel it’s time to move up to something with more grunt and would appreciate advice on what scope I should consider getting next?

I have an open mind but would like to see a noticeable gain with imaging, such as I did with the WO. Though I really like the refractor a lot, my inclination is perhaps an SCT next, such as the Celestron EdgeHD 800 or something similar? Given my objectives:

•      Is this big enough – if not then what?

•         Can this type of scope also be mounted on the AZ-EQ6 (I don’t really what another mount)?   

•         I expect that 90% of the time imaging will DSOs but I’d like to dabble with planetary imaging too, if possible.

•         Currently I’m only DSLR imaging but expect the next purchase after this with be a CCD, if that has any bearing on the choice of scope?

All ideas welcomed - thanks. Graham

[groberts]

Help still appreciated please. Any thoughts?

[Davey-T]

https://www.firstlightoptics.com/maksutov-newtonian/skywatcher-explorer-190mn-ds-pro-mak-newt-astrograph.html

Dave

[groberts]

Thanks, looks good but ideally would like something less bulky.

Any more suggestions please? 

  

[swag72]

Perosnally I think that the best improvement from your point would be a CCD camera rather than a new longer focal length scope. The CCD is more sensitive and you;ll also have the joys of narrowband. The summer is a great time of year for this

 

[groberts]

I guess I'm thinking aperture as much as FL.

Any particular camera; my leaning is colour - I know mono + filters is better but I just don't have the skies to do that.

Thanks.

 

 

[DHEB]

I am nowhere close to your level of expertise in AP, but if I were you I would seriously consider a Skywatcher Newtonian of the Quattro series. These are all f/4 Ttelescopes that come in 200, 250 and 300 mm apertures, i.e. 800, 1000 and 1200 mm FL. They are of course fit for your mount and are not so astronomically expensive either. The 200 mm can be considered relatively small and light. All are specifically designed as imaging scopes. Coma corrector is a must in these ones.

Just my 2 cents. Good luck!

[groberts]

Thanks for the thoughts - please keep them coming.  I remain uncertain + still interested in an SCT perhaps?

[Davey-T]

The only drawback with SCTs is their "speed" when imaging, I use mine for small galaxies, planetary nebula and planets / Moon etc with no problem but have other scopes for targets not suited to the SCT.

Dave

[groberts]

OK - I presume you mean they're too slow?

Notwithstanding, I like their compact nature - is there a compromise solution?

[DaveS]

Agree that a CCD and narrow band would make a huge difference, especially as you may have almost as much LP as I do, it's the biggest single improvement I made to my kit.

As for another 'scope I have to say too that the 190MN represents huge value, giving you 1000mm fl and f/5.3 without needing a coma corrector. Trying to do that in an apo 'frac leads into second mortgage territory.

Remember that for AP the aperture is the least important aspect of a 'scope.

[groberts]

Thanks. When you say "narrowband", what do you mean:  a narrow band filter?  If so what sort? Also any thoughts on CCD - I know mono's the way to go but with LP, cloud and the moon I'm inclined towards colour.   

 

[Davey-T]

There's been lots of discussion on mono versus colour on this and other forums, in a perfect world with clear skies and loads of money then mono whether  LRGB or narrowband is king, however in the UK , and strapped for cash, some pretty spectacular results have been achieved using DSLRs even unmodded ones.

A colour CCD  although saving on the cost of filters and filter wheel is probably not much of an advancement on your DSLR, so a second hand Atik314L and Atik EFW2 filter wheel could be around £650 to £750 without filters, an Atik 314 is well suited to an SCT if you go that route.

Dave

[matt-c]

15 minutes ago, groberts said:

Thanks. When you say "narrowband", what do you mean:  a narrow band filter?  If so what sort? Also any thoughts on CCD - I know mono's the way to go but with LP, cloud and the moon I'm inclined towards colour.   

 

Narrowband is your friend with light pollution and the moon to some extent but only worth while on a mono ccd.

As far as ccd go i know alot of people like the atik brand in particular the 16hr/314 and 383l for peoples first ccd.

There is so much choice though so dont feel like thats what you need to get.

Also even if i had amazing skies i'd still shoot narrowband because.....its amazing!!!! (slightly biased )

[uhb1966]

... i believe if you want to substantially improve, you might have to think "cooled" CCD, or the new cooled ZWO CMOS ... not my personal experience, though, only hearsay. I do own a skywatcher 200mm quattro w/ Baader flattener and i'm happy with it; it's about half the price of an 80mm apochromatic refractor which seems to be what many astrophotographers are using. The 200mm quattro, of course, also collects 5x the light of the 80mm at half the price...

decisions, decisions!

 

[groberts]

Thanks all, I'm taking it all on board and in my usual fashion will no doubt procrastinate for some time.

I have to take out all my equipment each time and absolutely love my WO GT81 as it's very well made, small, convenient, easy to use and quick to set up + outstanding optics + great FOV for larger DSOs + I also appreciate the closed nature of a refractor which is less hassle than Newtonians regarding temperatures and maintenance.  However, as mentioned in my OP I am increasingly feeling the lack of power with the WO when it comes to galaxies and smaller DSOs + is obviously inadequate for planetary - though that's less important.

I currently use a modded 550D + LP clip filter which for the moment does a decent job.  I realise CCD is generally better but by the time I've set up all this paraphernalia + aligned etc etc + what I'm finding are limited weather conditions the addition of taking x3 or more sets of images with filters is just a step too far.  I'm therefore inclined to the principle of KISS, which in this case means colour.

 

   

 

      

[DaveS]

You don't *have* to do colour. Have a look in the DSO imaging forum and you'll see plenty of mono images in H-alpha.

Going narrow-band with H-alpha also means you can image in moderate moonlight. OK a full moon high in the sky pretty well wipes things out, and [OIII] can be problematic, but otherwise you're OK.

[Davey-T]

Forget the new scope and build an obs'y 

Dave

[MattJenko]

To up the grunt factor, I presume you are talking about increasing focal length from your WO81. A good galaxy and PN focal length which remains very possible on the AzEQ6 is at around 1-1.5m. The SCT you mention is way past that and will make rather big demands from the AzEQ6 and even the reducer (which is a lot of $$$) will not help that much. There are more options than an SCT for longer focal length though, and the best have already been mentioned. The MN180, a decent 8" reflector and also you can delve into the world of RC imaging, with an 8" RC, coming in at 1.6m focal length without reducer.

[Starpaw]

I know nothing about AP, but a Celestron C6 has a 1.5m focal length and is F/10,  plus it's very compact.  You could also consider the Skywatcher ED 100, which is F/9, though less compact than the former.  I assume both would give you the extra grunt for small DSOs, plus planets, at the expense of longer exposure times (a focal reducer would help here?).  There's also a 6" GSO Ritchey Chretien Astrograph with a focal length of 1.3m and focal ratio of 9.  I'm only suggesting these because I have been considering them, bar the last one, for visual use and desire more grunt for smaller DSOs too.

[groberts]

1 hour ago, Davey-T said:

Forget the new scope and build an obs'y 

Dave

I would if I could but would need to move house first: I have no views to the north and limited viewing west/south/east due to trees and houses!

[Tyson M]

I think the RC scopes are compact, good for galaxies or smaller DSO's. 

 

SCTs are long focal length , unless hyperstarred- they are planetary imaging units. Or visual only, IMO. There are tons of ppl who do amazing work with 8" edge though. 

 

 I've seen great results with a C11 edge on galaxies and such, but you need a long focal length guide scope w/good guiding, heavy duty mount like an eq8. Lots of patience and time haha. 

[groberts]

Am now thinking, either:

1. The 800 Edge + focal reducer (=f7) or something comparable?
2. A compact (?) RC?
3. A bigger refractor: what size would give a noticeable improvement on the WO GT81 + makes?

All to work on AZ-EQ6 mount.

[groberts]

OK I am slowly making progress.  For various reasons have narrowed my choice to either a refractor or SCT + focal reducer, with the refractor probably favoured at the moment. The possible choices currently being:

1. Explore Scientific 127 ED APO 127 f7.5

2. A Celestron Edge or Meade ACF, probably 8"

Will these do the job + any comments?

 

Thanks, Graham 

   

    

[Andyb90]

I'm looking at a possible scope and camera upgrade. I've found the FLO fov calculator very useful.

You can input your scope choices, camera and object to get a good idea of the fov.

Andy.