spotting scope for astronomy

[rowan46]

I was looking at the celestron 100 ed-f spotting scope

pro's

under £500 for an ed 100 apo

rugged

small for an ed 100

takes astro eyepieces

light enough to carry as I have no car

cons

that 45 degree prism

have I missed anything?

[E621Keith]

A good tripod with a fluid or geared head, and some kind of finder.

Sporting scopes has tapered optical tube and slightly offset prism which makes aiming a target much more difficult than a similar astro scope.

A 45deg prism isn't too bad in practice, and more comfortable to use than a straight trough system. Most spotting scopes are also very light which is perfect for a grab and go.

You need to be aware most spotting scopes are not designed for high magnification work, the image in my old Pentax PF80 EDA began to deteriorate between 60-80x magnification. Most 80mm astro apo can handle double that magnification without much problem. I think this is caused by the complex internal focusing mechanism and multiple prisms in the spotting scope which is absent in an astro scope.

[moriniboy]

How about a C90 mak not the best for dso's but great for birding and planets. I flocked mine to improve contrast - well worth it.

Dont use the 45 deg prism which came with the scope and just use a 1.25 diagonal

[rowan46]

How about a C90 mak not the best for dso's but great for birding and planets. I flocked mine to improve contrast - well worth it.

Dont use the 45 deg prism which came with the scope and just use a 1.25 diagonal

thanks for the replies i have a c5 on a nexstar mount but fancied something a little faster for photo's

[E621Keith]

thanks for the replies i have a c5 on a nexstar mount but fancied something a little faster for photo's

If you plan on using the spotting scope for imaging, then you should just get a astro scope. Most spotting scopes have very limited focus travel and often the only way to image is using eyepiece projection. My old Pentax won't even reach infinity focus with some of my astro eyepieces.

[rowan46]

thankyou keith. as usual there is a problem in my quest for a portable system to view and take a couple of pics with. I was hoping that i would be able to take a few of the brighter dso's and have enought apparture to view I really am looking for portability as I am so fed up having to take the push chair with all the astro gear out at night I can get it all on my back but it can be very heavy after a long day at work. anybody got any ideas for a scope that fits the bill at about £500. needs to be portable, fairly rugged big enough apparure to view with from a fairly polluted sight and fast enough to stick a camera on and get some of the brighter dso's and hopefully light enough to be carried by a photo tripod?

[E621Keith]

thankyou keith. as usual there is a problem in my quest for a portable system to view and take a couple of pics with. I was hoping that i would be able to take a few of the brighter dso's and have enought apparture to view I really am looking for portability as I am so fed up having to take the push chair with all the astro gear out at night I can get it all on my back but it can be very heavy after a long day at work. anybody got any ideas for a scope that fits the bill at about £500. needs to be portable, fairly rugged big enough apparure to view with from a fairly polluted sight and fast enough to stick a camera on and get some of the brighter dso's and hopefully light enough to be carried by a photo tripod?

An ED80

The Celestron Regal 100ED spotting scope is a f5.4 scope, which is very fast for a refractor. The only apo refractors with that kind of focal ratio are very expensive Petzvals like the Takahashi FSQ and TV NP101. I'm skeptical of the benefit of the ED element in this spotting scope, I think it will only reduce the false colour to that of a good achromat / semi apo. It should be a bit better than a F5 achromat like the ST102, but I don't expect it to be close to the ED100/102.

Big aperture, low cost and portable are contradictory terms. For portability (size) and aperture, folded reflectors like SCT and Mak usually wins, but they loose out on durability. If durability and portability is your main objective then a refractor or a spotting scope will be your first choice, but they are expensive and small.

The only 4" apo close to your budget is the Altair 102 ED doublet, but the reviews of Altair ED doublets are not very encouraging. IMHO, the proven ED80 will be your best bet