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Tom the Tenor
19th May 2008, 18:22
I am thinking of taking the plunge and buying a telescope or more correctly a spotter scope. A pal of mine whom is a big astronomy fan is urging me to to be sure to get an angled (45 degree) 'scope for comfort of viewing rather than the straight variety. My pal is assuming the use of a tripod but I am not too sure about that except for maybe the back garden.

So, what do you think? My sight is far from great and I wear fairly thick glasses lenses in spite of a high refractive index on my specs so good eye relief would be important for me on any new 'scope.

Thanks and a big hello from Cork!

Playamar2
19th May 2008, 18:45
A straight scope every time for spotting. You'll never find an aircraft in flight with an angled scope. Angled scope OK for aircraft on the ground and taxi-ing speed.

Playamar2

HEATHROW DIRECTOR
19th May 2008, 20:37
I have considerable expereince with high power telescope for bird watching. An angled scope allows you to look up at a higher angle and it's quite easy to get on target with a bit of practice. One solution is to tape a small tube - even a piece of drinking straw - along the side of the scope. View a fixed object through the scope and then align the tube on the same object. Then when you need to find anothe object simply line up the viewing tube and slook through the scope. It really does work.

Bushfiva
20th May 2008, 06:10
A flip mirror (either integral to the 'scope or as an accessory) will give both options.

If you're not sure whether you want to use a tripod, then consider image-stabilized binoculars. Firstly, you won't be able to hand-hold a serious telescope, and secondly you won't be able to locate/track a moving target with an angled viewfinder.

HEATHROW DIRECTOR
20th May 2008, 09:12
I'm not familiar with a "flip mirror". All the scopes I've owner have used prisms.

Whether one can hold it depends on experience - and strength of muscles!! There are many aircraft spotters to be seen using old fashioned brass draw telescopes which they hand-hold with great effect. I can't do it, but i can use my heavy 15x60 binoculars which some people can't.

If you are going to buy a good telescope expect to pay many hundreds of pounds or you may get junk. Optolyth and Swarovski are pretty good, but pricey.

Bushfiva
20th May 2008, 09:46
I'm not familiar with a "flip mirror".

It's just a generic term which can cover a range of technologies. It's a good search term to start with. My telescope has one internally for astrophotography: I can leave the camera attached at the end, set up the shot with the top eyepiece, and flip the mirror out of the light path for the actual shot. This is front-silvered stuff, of course, so the image degradation is minimal. I know there are eyepiece extensions out there and telescope designs that allow "rear look" and "side look" on the same telescope. I was just trying to demonstrate that they're not mutually exclusive.

And of course, since I'm into astrophotography, I can navigate guru-like through a right-angled lens and an inverted image. But my brain would explode if I tried to follow an aircraft with this setup. Hand-held, I'd probably fall over, too.

Tom the Tenor
20th May 2008, 20:31
Thank you, gentleman, for your contributions to my query. The straight through scope or the angled scope question is definitely a good topic for discussion from the aviation enthusiast point of view. Now, if money was no object one of the more expensive draw scopes from Swarovski from about £549 up would be the job but it is hard to justify such an amount of expense as per Heathrow Director's comment above on pricey scopes so that is out of the running for me. I am inclined to consider the Celestron Ultima models that are more modesty priced and the brand seems to be well got amongst the astronomy enthusiasts. Birdwatching magazine are recommending an Avian model, the Avian Multiview 80, but in their review they would like a tad more eye-relief.

Thank you, Heathrow Director, for the tip about using an attached straw to line up the object for viewing with the angled scope. Such effective simplicity! :D