Scopes (which one?)

[rabbs]

I have been looking a scopes for a while now, just something to get me started (read budget).

For about the same money I have a choice of a 900mm f12 refractor or a 500mm f4 reflector, both are skywatchers.
By my way of thinking the f4 on the reflector would be the way to go, and I guess this post is just looking to validate my way of thinking.

With the focal length, I relise that the 500 has a wider field of view, but because I have never looked through anything that long I just can't picture it in my minds eye.

I would be grateful for your views.

[chris.bailey]

Hi Jason

What are your intended targets? I am assuming you want something to image with rather than pure visual use or at least have the option to image?

A 900mm f12 refractor is very long and at the same time very slow for imaging. The 500mm F4 Newt would be a better prospect but getting focus onto an imaging device normally means having to retrofit a low profile focusser. Add in collimation and cool down and Newts are a bit of a frustration if you dont have a lot of patience. Probably fine for visual work but I would not recommend one for a beginner trying to image.

For sheer ease of use in imaging a refractor takes some beating.

I you want a cracking scope for imaging, go for the 500mm Equinox f6.2. Good field of view and fantastic optics for the money. I know lots of people who image with them with a 0.8 or 0.63 focal reducer/field flattener and produce images that outgun scopes costing much more. Its got a pretty fine Crayford focusser and good back focus for imaging.

May stretch your budget a bit as it does not come with a mount but will be a scope that you keep for a while.

[chris.bailey]

...another fine little scope is the Williams Optics ZS70 which in the UK is on special offer with the W/O TRF tripod. The ZS70 is 430mm f 6.2 which makes it a nice setup for wider field imaging. I have one and other than a bit of colour fringing at the edges its a great little scope. Very portable too!

[Adrena1in]

So the 900mm has a 75mm aperture, and the 500mm has a 125mm aperture? Look at it like this...put a 2x Barlow on the 500mm and you have a 1000mm f/8...which is better than the 900mm f/12. I'd say get the 500mm personally.

However, if you want to image through the scope then I think you want to go down the Refractor route.

[cruiser]

Hi Rabbs,

When getting your scope, if your thinking that astrophotography might be an interest make sure the mount it is attached to is sturdy enough to take the extra weight of the camera etc. Nothing kills a star shot quicker than a bit of shake in the breeze.

Brett

[Adrena1in]

I've also just re-read your post and say the choice is between a refractor or reflector. Not always that easy taking photos through a reflector...thought I'd point that out.

[rabbs]

Thanks for the advice guys.
I think what I will do is invest in a mount first and save for a better refractor later down the line.

Thanks again.

[A.S.I.G.N. Observatory]

Jason, I may be able to help with some info for you. I started from scratch with no knowledge and no help. Good way to learn.

Here's a page I wrote some time ago.
http://www.asignobservatory.com/tips_and_advice.aspx

There's lots more in the menu's on the left too. hope it helps mate.

Baz.

[rabbs]

Thanks for the link, some great reading.
btw you do some fantastic work.

[A.S.I.G.N. Observatory]

Thanks for the link, some great reading.
btw you do some fantastic work.

My pleasure mate. Thankyou.