Zeiss gavia, vortex razor or Kowa 773 (1 Viewer)

[Glyn Watts]

Hello all would welcome opinions regarding choice between these scopes. I seem to be going round in circles !! I really like the idea of zeiss and it would be a lot easier to source where I live but l am open to all suggestions

 

[jring]

Hi Glyn,

I personally have not looked through the two Kamakura made options, the Gavia and the Vortex Razor. Henry Link has reviewed the Gavia and a 3rd member of the Kamakura family (called Brunton Icon) and was not impressed - but he is a very experienced reviewer and will find every flaw!

The 773 has also got its share of lackluster press, although mostly in direct comparison to its top of the line brother 883 which is not a lot larger or heavier and at least for many years also was not a lot more expensive.

I personally did not find the view through the single 773 I have looked through objectionable, but of course this was just looking through a fellow birder's scope at some interesting bird, not a formal test.

If I was looking for a nice scope around 80mm at a budget, I would certainly look at the Nikon Monarch 82mm or the Meopta S2 too...

Or go used and find a nice 883 or ATS/M 85...

Joachim

 

[qwerty5]

Hello all would welcome opinions regarding choice between these scopes. I seem to be going round in circles !! I really like the idea of zeiss and it would be a lot easier to source where I live but l am open to all suggestions

First of all, they are in three different price ranges. Razor for $1600, Zeiss for $2000. The Kowa body costs $1600 but eyepieces are sold separately. A kowa 25-60x zoom will cost $700, making it cost $2300 total.

The Razor and Zeiss 85mm has a larger objective than Kowa's 77mm. A larger objective will let in more light and generally be better optically when comparing similar price optics. However since the Kowa costs more than the others, the difference probably isn't much.

The Kowa 25-60x eyepiece has a 75-138 ft FOV.
The Zeiss 30-60x eyepiece has a 69-99 ft FOV.
The Vortex 27-60x eyepiece has a 68-117 ft FOV.

Here's a review of the Zeiss vs. Vortex: Spotting Scopes 85mm Review 2017 - by Michael and Diane Porter.
Based on that review, the Zeiss is not any better than the Vortex, but it costs $400 more, so I would throw out the Zeiss.

It's up to you to decide whether you want to spend $1600 for a Vortex or $2300 for a Kowa. The Kowa will probably be better, but keep in mind it costs $700 more and has a smaller objective.

 

[Bill Atwood]

Hello all would welcome opinions regarding choice between these scopes. I seem to be going round in circles !! I really like the idea of zeiss and it would be a lot easier to source where I live but l am open to all suggestions

Have you had the chance to use any scopes?

 

[Glyn Watts]

Hi Glyn,

I personally have not looked through the two Kamakura made options, the Gavia and the Vortex Razor. Henry Link has reviewed the Gavia and a 3rd member of the Kamakura family (called Brunton Icon) and was not impressed - but he is a very experienced reviewer and will find every flaw!

The 773 has also got its share of lackluster press, although mostly in direct comparison to its top of the line brother 883 which is not a lot larger or heavier and at least for many years also was not a lot more expensive.

I personally did not find the view through the single 773 I have looked through objectionable, but of course this was just looking through a fellow birder's scope at some interesting bird, not a formal test.

If I was looking for a nice scope around 80mm at a budget, I would certainly look at the Nikon Monarch 82mm or the Meopta S2 too...

Or go used and find a nice 883 or ATS/M 85...

Joachim

Thanks Joachim for the advice and suggestions I will need to look into them !

 

[Glyn Watts]

Have you had the chance to use any scopes?

Hi Bill I’m currently using an opticron mm4 ga Ed 60 mm with sdl v3 zoom eyepiece but am looking to upgrade

 

[Glyn Watts]

First of all, they are in three different price ranges. Razor for $1600, Zeiss for $2000. The Kowa body costs $1600 but eyepieces are sold separately. A kowa 25-60x zoom will cost $700, making it cost $2300 total.

The Razor and Zeiss 85mm has a larger objective than Kowa's 77mm. A larger objective will let in more light and generally be better optically when comparing similar price optics. However since the Kowa costs more than the others, the difference probably isn't much.

The Kowa 25-60x eyepiece has a 75-138 ft FOV.
The Zeiss 30-60x eyepiece has a 69-99 ft FOV.
The Vortex 27-60x eyepiece has a 68-117 ft FOV.

Here's a review of the Zeiss vs. Vortex: Spotting Scopes 85mm Review 2017 - by Michael and Diane Porter.
Based on that review, the Zeiss is not any better than the Vortex, but it costs $400 more, so I would throw out the Zeiss.

It's up to you to decide whether you want to spend $1600 for a Vortex or $2300 for a Kowa. The Kowa will probably be better, but keep in mind it costs $700 more and has a smaller objective.

Hi and thanks for the reply !! You make some really good points and I will certainly give your advice solid consideration. Ideally it would be great if I could look through a few of them but I’m not in a position to check all of them out barring the Zeiss. The way you state the case the vortex looks like a good value option however

 

[jring]

Hi Bill I’m currently using an opticron mm4 ga Ed 60 mm with sdl v3 zoom eyepiece but am looking to upgrade

Hi Glyn,

what are you missing in the view of your MM4? Have you star-tested it?

Joachim

 

[Glyn Watts]

Hi Glyn,

what are you missing in the view of your MM4? Have you star-tested it?

Joachim

Hi Joachim excuse my newbie ignorance but how do I do such a test ?

 

[jring]

Hi,

easiest on a cool and clear night... search a bright star - on the northern hemisphere Polaris is a good choice (elongate the front edge of the big dipper or back end of Ursa Major 5 times until you get to a bright star - straight north or the front end of Ursa Minor) as it doesn't move (a lot).

Bring the star to best focus at maximum magnification (in a spotting scope) and you should see a dot - or if the magnification is high enough - a dot with a faint ring around it - this is the diffraction pattern of the unobstructed aperture and is called Airy disc.

Now you defocus the scope a tiny bit in each direction and observe the diffraction patterns. Ideally you want to see equal patterns of well defined, concentric rings on each side.
This is a very rare case, experienced star testers which have tested hundreds or thousands of scopes tend to remember the 1 or 3 perfect examples they might have been lucky enough to have looked through.
I am still searching for one.

If you don't, what you see tells you what aberrations are present - just the most common ones:

- ellipses instead of circles - astigmatism aka stig

- well defined patterns on one side of focus, a fuzzy disc on the other - spherical aberration aka SA

- non-concentric patterns - coma

- yellowish on one side, blue/violet on the other - chromatic aberration

See the images on the following page for examples - you are always interested in the unobstructed case - the upper image for each aberration. Please don't be afraid of the rather heavy math... this is a good text book on telescope optics and a bit heavy.

Star testing telescope optical quality

The basics of star testing telescope: diameter of artificial star, distance induced spherical aberration.

www.telescope-optics.net

Joachim

 

[Glyn Watts]

Hi,

easiest on a cool and clear night... search a bright star - on the northern hemisphere Polaris is a good choice (elongate the front edge of the big dipper or back end of Ursa Major 5 times until you get to a bright star - straight north or the front end of Ursa Minor) as it doesn't move (a lot).

Bring the star to best focus at maximum magnification (in a spotting scope) and you should see a dot - or if the magnification is high enough - a dot with a faint ring around it - this is the diffraction pattern of the unobstructed aperture and is called Airy disc.

Now you defocus the scope a tiny bit in each direction and observe the diffraction patterns. Ideally you want to see equal patterns of well defined, concentric rings on each side.
This is a very rare case, experienced star testers which have tested hundreds or thousands of scopes tend to remember the 1 or 3 perfect examples they might have been lucky enough to have looked through.
I am still searching for one.

If you don't, what you see tells you what aberrations are present - just the most common ones:

- ellipses instead of circles - astigmatism aka stig

- well defined patterns on one side of focus, a fuzzy disc on the other - spherical aberration aka SA

- non-concentric patterns - coma

- yellowish on one side, blue/violet on the other - chromatic aberration

See the images on the following page for examples - you are always interested in the unobstructed case - the upper image for each aberration. Please don't be afraid of the rather heavy math... this is a good text book on telescope optics and a bit heavy.

Star testing telescope optical quality

The basics of star testing telescope: diameter of artificial star, distance induced spherical aberration.

www.telescope-optics.net

Joachim

Thanks Joachim I will give it a try