Scope advice

[Biggz]

I am looking for a bit of advice. I'm trying to get in to astrophotography and my current equipment is an EQ1 tabletop, with RA drive, DSLR and 10x50 bins. I've got no usable images yet as I've yet to get to grips with it, plus the light pollution is terrible from my upstairs window. I really need to take this to darker skies.

However, I would also like a scope for visual use and maybe photography once I upgrade to a better EQ mount, I'm thinking CG-5 if I can find one second hand.

I think I've narrowed it down to a couple of choices.

1. Skywatcher Startravel 80 OTA, I could use this as a guide scope if I ever wanted one.

2. Skywatcher Explorer 130P DS OTA. I know this will be too heavy for my EQ1 but I have a good tripod rated to carry 6Kg and from what I've found this OTA is 3.66Kg. I could maybe attach my DSLR to this on my tripod to capture unguided images.

What are the differences between the ST80 and 130P DS for visual use?

Are there any other light weight OTAs that would be okay for visual on tripod, and usable for photography at a later time?

Am I stupid thinking about putting a 130P on a tripod?

Thanks for your help!

David

[Carbon Brush]

Hi David.

I'm surprised that you haven't had any replies yet.

Here is my 2pennorth, issued with the condition that free advice can't be worth less than you pay for it.

CG5 is a good choice for the size & weight scopes you are looking at.

With this mount you can go up to an 8" reflector like the SW200P definitely visually. But it is on the limit for photos.

The ST80 is fine for wide-ish views. If you turn up the magnification, chromatic abberation becomes noticeable.

I haven't used the 130PDS so won't comment on specifics.

But you tend to get what you pay for on Skywatcher scopes.

Awaiting the next replies....

[Brian Nordstrom]

good advice David on the mount the CG5 is a good one , but the 200mm scope is a little heavy for it I think , a 150mm f/8 is lighter and gives better views of the Monn . Planets and double stars , with only a small loss of light gathering on the 200mm .

The f/8 of the 150mm gives awsome views ( I had one of these for a long time and loved it , my mate had a 200mm f/5 and the views were compareable )

Dave , forget the 130mm and 80mm as these 2 will show all they can very fast and you will want for more , its called " Apateure Fever "

Go the CG5 and 150mm or the 200mm ( as said the 200mm is a lot heavier ) , if your budget will allow .

Brian.

[Capricorn]

I had read it earlier but didn't reply.

It is the statement "I am trying to get into astrophotograpohy" that is the problem.

Astrophotography: LARGE mount and small scope. Think of the HEQ5 as a start.

The OTA for the for the 130P may be 3.66Kg, now add on the DSLR and the attachments and consider that for AP it is recommended to go to half or two thirds of the mounts capacity. That is just the OTA with nothing else - no DSLR.

ST80: Lots of CA, OK/reasonable as a guide scope, but guide scope and guide camera and mounting rings weigh a fair bit, and you are over the weight already without them. Also you would need a flattener for an ST80, that short a focal length on a DSLR would give a curved field.

You need to get more information, also seperate putting a visual scope on a mount from putting an imaging scope on a mount. For example, you may get away with a 200P on an EQ5 for visual, for imaging a 200P has too long a focal length and you would need an EQ6 owning to the weight.

I was talking with someone Saturday that had replaced their HEQ5 with an EQ6 as it was better with regards to stability for astrophotography and they have an 80mm triplet as the imaging scope.

My point is simple: If you are going to go visual then a large aperture scope is the way to go. If you are going to go imaging then a large mount is the start point, you then build on the large mount.

Imaging is expensive, and more frustrating the visual. You can view for an hour and see things, it could easily take over an hour to simply get a mount set up for imaging, and twenty 30 sec exposures does not take 10 minutes, closer to 2 hours.

[hemihaggis1]

hmm yes

[Biggz]

I've pretty much decided on a second hand CG-5 GOTO (if I can find one) as that's about the best I'll get for what I'm willing to pay at the moment.

You're all making me learn towards the 150pds but I cant for the life of me find how much it weighs. My idea was, if my tripod could handle it, was to use it for visual only until I upgraded my mount.

hmm yes

My thoughts exactly!

Thanks very much for your help so far!

David