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Spotting scope with high magnification.? (1 Viewer)


Well-known member
Currently I need a good spotting scope with which I can achieve magnitudes of the order of 80-90X with a good image and without excessive loss of luminosity, of course without C.A.
I do not know if there is a model that can provide me with this, I would be happy to hear your opinions and comments.
I have also thought of some small quality refractor with an ED lens, which can be fitted with an image erector and a zoom eyepiece, in fact I have the Baader Mark IV (with a 2.25 "barlow lens included in the set) ..
If any of you have had the chance to use this setup, I would also be interested in knowing your opinion.
Thank you very much.


Well-known member
Swarovski ATX 95 with 1.7x extender will give you a good image at 90x - but it‘s not cheap.



Well-known member

I'm afraid, the following describes the problem...

small, high magnification and bright image - choose any two...

An ED 120 would work just fine... but it is neither small nor light... some Mak or Schmidt-Cassegrain around 120mm aperture might be an option... but be prepared to test your example as the affordable ones vary in quality (and sometimes need some work to loosen a pinched primary).

An ATX 115 with extender will also work but is also not really light... but your wallet will be very light...



Well-known member
Opticron ES100 with either of their zooms will get you to 80x power. Now in mark IV guise. Kimmo did a review on an earlier version and deemed it a worthy, capable if heavy scope. Not mega expensive either.
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Well-known member
kona 883 w 1,6 extender, there is one for sale in norway on cloudynights, btw which ed refractor do you have?


Well-known member
kona 883 w 1,6 extender, there is one for sale in norway on cloudynights, btw which ed refractor do you have?


if you meant me - I do have a Skywatcher ED 120/900 with an FPL53 doublet - but the same Synta objectives are available from quite a few other brands - namely Celestron.



Well-known member
Maybe one small Maksutov 90mm or 125mm..for high magnification ?

Sure, but the tricky part is finding a good example... When you get one with bad astigmatism it is often helpful to take it apart and carefully reassemble without tightening the main mirror holding screws fully. If one does that, the mirror will be "pinched" and astigmatism is the result. A slight rattle is the desired result.



Old Berkshire Boy
Do Questar still produce a Field Model? They were used throughout the 1980s and early 90s by a few birders. For what main purpose are you seeking this high magnification.


Well-known member
I have used dozens of Maksutov Cassegrains and mirror lenses as terrestrial telescopes from 50mm to 150mm clear aperture.

They vary enormously in quality.

The Celestron C70 was poor.
The small Konus spotter was awful.
The Mirador 70mm superb.
The Skywatcher 90mm excellent at all powers from 65x to 190x with a best magnification of about 130x with a bright sun behind.
The Questar 89mm very good.
The Skywatcher 127mm (true 118mm), average.
Pentax spotter average.
Zoomatar 2000mm f/14 bad cooling and tube currents always.
Zoomatar 500mm f/5.6 quite good.
Celestron 500mm f/5.6 average.
Celestron 750mm f/6 quite good.
Nikon 500mm f/5 good.
Nikon 500mm f/8 good.
Canon 500mm f/8 good
Minolta 500mm f/8 good in AF and MD, different apertures.
Vivitar 600mm f/8 superb at 120x excellent at 180x Easily split 2.4 arcsecond double stars.
Optomax 500mm f/8 very good at 150x.
150mm f/10 custom Maksutov good.
150mm f/15 custom Maksutov superb.
BAS 90mm rather poor.
Russian 65mm or 70mm very good.
Russian 100mm Maksutov superb.
Russian 100mm MTOs they vary considerably and have tube currents.
Delft 140mm aperture military Maksutov superb.
Bell and Howell 650mm average.
Tamron 500mm f/8 good.
Sigma 500mm f/4 poor.

Etc. etc.

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Well-known member
Although the Skywatcher 90mm Maksutov is excellent with a bright sun behind, it is low on contrast in dull conditions.

The 150mm f/10 Maksutov was good in all conditions. I used a Porroprism erector.

Generally Maksutov Cassegrains lose contrast if they have large secondaries, unless very well designed.

For aircraft flying, I think a long focus 80mm refractor is better, sighting along the tube at 50x to 80x.
Possibly also an 80mm ED refractor, or 100mm ED or 120mm ED similar.
These will also have higher contrast and can use wide field eyepieces.

For aircraft on the ground far off, probably 120x, maybe more depending on location, observing height and conditions.

The advantage of the Maksutov is compactness.


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