Kowa 66a vs 773 (2 Viewers)

[StephenL]

Hi all,

Hopefully looking for opinions and advice on the above two scopes as I am thinking of upgrading to either the 66a or the 773 and wondered if anyone has used both and is able to give a comparison between them. Just to clarify I am interested their optical differences only, if there are any.

A few months ago I was lucky enough to try the 66a and was very impressed by the optical difference which, to my eyes, was measurable between it and my MM4 77 and I wondered if the 773 would give the same experience.

At the moment there are some deals on the 773 which are quite attractive and was one of the reasons I am considering it along with retaining the same size of objective lense as i currently have.

One other question, has anyone any experience of the fixed Te 80xw eyepiece as I currently use and prefer a fixed eyepiece and wondered how it compared to the Te 11 WZ ii zoom eyepiece.

Thanks in advance,

Stephen

 

[CMB]

Hi all,

Hopefully looking for opinions and advice on the above two scopes as I am thinking of upgrading to either the 66a or the 773 and wondered if anyone has used both and is able to give a comparison between them. Just to clarify I am interested their optical differences only, if there are any.

A few months ago I was lucky enough to try the 66a and was very impressed by the optical difference which, to my eyes, was measurable between it and my MM4 77 and I wondered if the 773 would give the same experience.

At the moment there are some deals on the 773 which are quite attractive and was one of the reasons I am considering it along with retaining the same size of objective lense as i currently have.

One other question, has anyone any experience of the fixed Te 80xw eyepiece as I currently use and prefer a fixed eyepiece and wondered how it compared to the Te 11 WZ ii zoom eyepiece.

Thanks in advance,

Stephen

The 66a has a pure fluorite objective lens, while the 773 uses ED glass. The 66a should control color fringing better than the 773 due to this higher grade objective lens. If you are someone who sees color fringing very easily, then the 66a would be the better choice in terms of optical quality. If you are someone who does not see color fringing, then the extra cost of pure fluorite objective lens may not be worth it in terms of image quality.

The two scopes have roughly the same focal length. The field of view with the TE-11WZ eyepiece is listed as the same for both scopes. The exit pupil will be larger on the 773 due to it having a larger objective lens than the 66a.

Because both scopes use the TE-11WZ II zoom lens, they will have the same generous eye relief through the zoom range.

 

[StephenL]

The 66a has a pure fluorite objective lens, while the 773 uses ED glass. The 66a should control color fringing better than the 773 due to this higher grade objective lens. If you are someone who sees color fringing very easily, then the 66a would be the better choice in terms of optical quality. If you are someone who does not see color fringing, then the extra cost of pure fluorite objective lens may not be worth it in terms of image quality.

The two scopes have roughly the same focal length. The field of view with the TE-11WZ eyepiece is listed as the same for both scopes. The exit pupil will be larger on the 773 due to it having a larger objective lens than the 66a.

Because both scopes use the TE-11WZ II zoom lens, they will have the same generous eye relief through the zoom range.

Thanks CMB, appreciate the response. Will need to give some more thought but think I will end up going for the 66a.

Stephen

 

[23icon]

Both are very nice binos. However, I would take the 883 model. The 883 has better resolving power, is brighter and has less chromatic aberration due to pure fluorite chrystal lens element in the objective.

 

[StephenL]

Both are very nice binos. However, I would take the 883 model. The 883 has better resolving power, is brighter and has less chromatic aberration due to pure fluorite chrystal lens element in the objective.

Thanks 23icon but the biggest I would go would be the 773. I have no need for the 883 and would not get the full benefit of it for the type of birding that I do.

Stephen

 

[eitanaltman]

IMO if size/weight is your primary concern and you're willing to pay the extra, get the 66A. If you don't care that much and budget is a stretch, get a deal on the 773. The 773 has an inherent advantage with the larger aperture, but this is mitigated somewhat by the fluorite objective of the 66A.

I haven't yet seen the 66A in person but I've owned the 883 and 773 and tested the 553 extensively. I also compared to the newer 88A at an optics fair last year, which did present a slight improvement on the 883 performance, so I feel comfortable extrapolating that the 66A and 773 are optically going to be extremely similar optically. They use the same zoom eyepiece (which is superb) and have the same focal length. The physics of the larger aperture (with comparable glass/coatings) means the 773 will be slightly better in low light and/or higher mags. Whereas in normal daylight use and at lower magnification (which is where most of your time will likely be) the fluorite object and other minor refinements/improvements in the newer model mean the 66A will slightly outperform the 773.

In fact I "downgraded" from the 883 to the 773 because (for my uses) the size/weight savings was more important than the slight optical advantage of the larger 883. The 773 is really a miraculous compromise between the more compact size/weight of 65mm mid-size scopes and the >80mm "full-sized" birding scopes. At the time the 66A hadn't yet been announced, but I'm happy with my decision. People will mention how the 773 has more CA than the fluorite crystal Kowa scopes but the 773 is still excellent in this respect and it stays crisp and sharp all the way to 60x mag.

Also be conscious of sample variation, a cherry 773 sample will likely outperform an OK sample of the 66A (although Kowa possibly has improved sample variation on the newer models?). I would be concerned if you can't get clean, sharp focus at 60x under good conditions.

Here's a good comparison review between the Kowa 773 and some 65mm competitors: Kowa 77mm Spotting Scope Comparison and Review

You can see the 773 is basically the same size/weight as the 65mm scopes:


And here's a YT video comparing them:

Here's a screenshot from that video so you can see the size difference between 66A and 773 is pretty minimal:

 

[StephenL]

IMO if size/weight is your primary concern and you're willing to pay the extra, get the 66A. If you don't care that much and budget is a stretch, get a deal on the 773. The 773 has an inherent advantage with the larger aperture, but this is mitigated somewhat by the fluorite objective of the 66A.

I haven't yet seen the 66A in person but I've owned the 883 and 773 and tested the 553 extensively. I also compared to the newer 88A at an optics fair last year, which did present a slight improvement on the 883 performance, so I feel comfortable extrapolating that the 66A and 773 are optically going to be extremely similar optically. They use the same zoom eyepiece (which is superb) and have the same focal length. The physics of the larger aperture (with comparable glass/coatings) means the 773 will be slightly better in low light and/or higher mags. Whereas in normal daylight use and at lower magnification (which is where most of your time will likely be) the fluorite object and other minor refinements/improvements in the newer model mean the 66A will slightly outperform the 773.

In fact I "downgraded" from the 883 to the 773 because (for my uses) the size/weight savings was more important than the slight optical advantage of the larger 883. The 773 is really a miraculous compromise between the more compact size/weight of 65mm mid-size scopes and the >80mm "full-sized" birding scopes. At the time the 66A hadn't yet been announced, but I'm happy with my decision. People will mention how the 773 has more CA than the fluorite crystal Kowa scopes but the 773 is still excellent in this respect and it stays crisp and sharp all the way to 60x mag.

Also be conscious of sample variation, a cherry 773 sample will likely outperform an OK sample of the 66A (although Kowa possibly has improved sample variation on the newer models?). I would be concerned if you can't get clean, sharp focus at 60x under good conditions.

Here's a good comparison review between the Kowa 773 and some 65mm competitors: Kowa 77mm Spotting Scope Comparison and Review

You can see the 773 is basically the same size/weight as the 65mm scopes:
View attachment 1554700

And here's a YT video comparing them:

Here's a screenshot from that video so you can see the size difference between 66A and 773 is pretty minimal:
View attachment 1554702

Thanks for the comprehensive response eitanaltman. My own thoughts have been similar to yours in that most of my birding is during good daylight hours so the 66a will be fine. I am used to the weight of a 77 but as I intend my next scope to be my last then weight may be a factor as I get older. The cost differences are not huge and neither are the optical ones so at the end of the day it will come down to personal preference.

Stephen

 

[CMB]

Thanks for the comprehensive response eitanaltman. My own thoughts have been similar to yours in that most of my birding is during good daylight hours so the 66a will be fine. I am used to the weight of a 77 but as I intend my next scope to be my last then weight may be a factor as I get older. The cost differences are not huge and neither are the optical ones so at the end of the day it will come down to personal preference.

Stephen

The weight difference between the bodies of the 773 and 66a is not that much, about 6-7 ounces (170-198 grams). Same eyepiece will be used in both so those optics and weights are identical.

So…
Length: essentially the same
Weight: essentially the same
Focal length: essentially the same

The only real differences are larger aperature with ED glass vs smaller aperature with pure fluorite crystal.

The pure fluorite improves control of CA over ED. And it has been reported that the pure fluorite improves light transmission enough over ED glass to somewhat offset the difference in aperature size; enough that Kowa is discontinuing the 773.

Controlling CA is the biggest difference that remains.

If the prices are similar then get the one that controls CA better. That will be the optical improvement under all conditions.

If the prices are different, and you are not one who sees CA, then consider getting what is easiest to afford. You personally may not benefit from increased CA control fluorite provides, but you may benefit from the slightlty increased resolution the larger aperature provides even if the ED objective lens is slightly lower in transmission tha pure fluorite.

I see CA very very easily. It’s annoying. We have a TSN-883, and an Opticron MM4 60mm.

The TSN-833 is basically CA free and its larger aperature provides much better resolution and handles higher magnification.

In the Opticron MM4 60mm I see CA around the outer edge but not in the center. It has ED glass for the objective. With the combination of smaller objective and ED glass it is noticeable that images get darker at the highest magnification, as one expects. It is not a big deal in the middle of the day.

We use the Opticron MM4 a lot. Even though I see CA on the outside edge of the FOV, even though it has lower maximum magnification, and has a darker image at full magnification; in certain situations the smaller size and lighter weight offset the better optical performance of the TSN-883.

But in the case of the 773 and 66a, they are more similar than different. Given that I see CA very easily, I’d select the 66a and not think twice about it.

 

[StephenL]

The weight difference between the bodies of the 773 and 66a is not that much, about 6-7 ounces (170-198 grams). Same eyepiece will be used in both so those optics and weights are identical.

So…
Length: essentially the same
Weight: essentially the same
Focal length: essentially the same

The only real differences are larger aperature with ED glass vs smaller aperature with pure fluorite crystal.

The pure fluorite improves control of CA over ED. And it has been reported that the pure fluorite improves light transmission enough over ED glass to somewhat offset the difference in aperature size; enough that Kowa is discontinuing the 773.

Controlling CA is the biggest difference that remains.

If the prices are similar then get the one that controls CA better. That will be the optical improvement under all conditions.

If the prices are different, and you are not one who sees CA, then consider getting what is easiest to afford. You personally may not benefit from increased CA control fluorite provides, but you may benefit from the slightlty increased resolution the larger aperature provides even if the ED objective lens is slightly lower in transmission tha pure fluorite.

I see CA very very easily. It’s annoying. We have a TSN-883, and an Opticron MM4 60mm.

The TSN-833 is basically CA free and its larger aperature provides much better resolution and handles higher magnification.

In the Opticron MM4 60mm I see CA around the outer edge but not in the center. It has ED glass for the objective. With the combination of smaller objective and ED glass it is noticeable that images get darker at the highest magnification, as one expects. It is not a big deal in the middle of the day.

We use the Opticron MM4 a lot. Even though I see CA on the outside edge of the FOV, even though it has lower maximum magnification, and has a darker image at full magnification; in certain situations the smaller size and lighter weight offset the better optical performance of the TSN-883.

But in the case of the 773 and 66a, they are more similar than different. Given that I see CA very easily, I’d select the 66a and not think twice about it.

Thanks CMB,

CA is not something that I see, thankfully. They are both affordable but I was really wanting to see if there was a noticeable difference, optically, between them which, going on previous posts and youtube videos, there appears not to be then so it it will come down to personal preference and what feels the right choice when I pull the trigger.

Stephen

 

[kabsetz]

CMB gave a very good summary of the similarities and differences (or lack thereof) between the two Kowas. I don't have much to add, but since I am currently in the process of testing the 66A to write a short Finnish-language review of it, I can second the recommendation. It is a truly nice scope, and more free of CA than any spotting scope save possibly the 88 and 99. My experience of the 773 is from a long time ago when I reviewed them for Alula, and back then I rather clearly preferred the 883 due to less CA, better contrast and less light scatter, which are all benefits the fluorite lens give.

The resolution benefit of extra 11 millimetres of aperture are real, though, but on the whole, if it were me, I would probably get the 66A although I generally think bigger is better.

The 40x wide-angle eyepiece I have tried briefly and it is fantastic, but so is the 25-60x zoom, and the added versatility the zoom offers is significant. It is a matter of preference, though, and you cannot go wrong either way.

- Kimmo

 

[StephenL]

CMB gave a very good summary of the similarities and differences (or lack thereof) between the two Kowas. I don't have much to add, but since I am currently in the process of testing the 66A to write a short Finnish-language review of it, I can second the recommendation. It is a truly nice scope, and more free of CA than any spotting scope save possibly the 88 and 99. My experience of the 773 is from a long time ago when I reviewed them for Alula, and back then I rather clearly preferred the 883 due to less CA, better contrast and less light scatter, which are all benefits the fluorite lens give.

The resolution benefit of extra 11 millimetres of aperture are real, though, but on the whole, if it were me, I would probably get the 66A although I generally think bigger is better.

The 40x wide-angle eyepiece I have tried briefly and it is fantastic, but so is the 25-60x zoom, and the added versatility the zoom offers is significant. It is a matter of preference, though, and you cannot go wrong either way.

- Kimmo

Thanks Kimmo,

I am leaning towards the 66a and as Kowa are discontinuing the 773, as they believe the 66a to be equal to it (so I am led to belive) then I have every confidence that the 66a will suit my needs. I do enjoy a fixed eyepiece but will get the zoom to begin with and go from there.

Stephen

 

[Nethero]

I have nothing to really add to this discussion except for this small bit. I recently was able to sit behind the Kowa 66A and a Leica Televid 65 (the newest black bodied one) side by side. The Kowa was hands down the brighter, more superior scope. Free from CA and razor sharp throughout the zoom. The Leica is fantastic too, but it just seemed “duller”, almost like it was overcast vs. sunny going from one scope to the other.

It was the brightness that really struck me though. CA control and wide fields are nice, but the overall image just popped because of how illuminated the image appeared.

 

[StephenL]

I have nothing to really add to this discussion except for this small bit. I recently was able to sit behind the Kowa 66A and a Leica Televid 65 (the newest black bodied one) side by side. The Kowa was hands down the brighter, more superior scope. Free from CA and razor sharp throughout the zoom. The Leica is fantastic too, but it just seemed “duller”, almost like it was overcast vs. sunny going from one scope to the other.

It was the brightness that really struck me though. CA control and wide fields are nice, but the overall image just popped because of how illuminated the image appeared.

Thanks for your thoughts Nethero. Good to know and something I will bear in mind.

Stephen

 

[7gannets]

I have used the 773 for a long time and upgraded to the 88a six months ago. I can say that the 773 still a great scope, with almost the same image quality as the 88A but of course less bright, which is imo the biggest difference between the two. It is true that CA is more controlled on the 88a but that doesn’t mean that it is bad in the 773, on the contrary they are are rarely distracting (and I am very sensitive to CAs). I should mention that i use the 773 with the wide 30x eyepiece, which is also excellent and now discontinued as well.
My guess is then that iq differences compared to the 66a will not be huge and still probably better on the 773. The weight and size between both is comparable but the larger objective on the 773 will give it the upper hand. Even if you won’t use it at sunrise or sunset, you get better details when the birds are in the shadow, like in bushes/trees, or under bad lighting e.g., against the sun.

 

[StephenL]

I have used the 773 for a long time and upgraded to the 88a six months ago. I can say that the 773 still a great scope, with almost the same image quality as the 88A but of course less bright, which is imo the biggest difference between the two. It is true that CA is more controlled on the 88a but that doesn’t mean that it is bad in the 773, on the contrary they are are rarely distracting (and I am very sensitive to CAs). I should mention that i use the 773 with the wide 30x eyepiece, which is also excellent and now discontinued as well.
My guess is then that iq differences compared to the 66a will not be huge and still probably better on the 773. The weight and size between both is comparable but the larger objective on the 773 will give it the upper hand. Even if you won’t use it at sunrise or sunset, you get better details when the birds are in the shadow, like in bushes/trees, or under bad lighting e.g., against the sun.

Thanks 7gannets,

I opted for the 66a, in the end, for a variety of reasons and I see it as my forever scope. Not had a great deal of use from it yet but when I have used it I am hugely impressed. I got the fixed eyepiece along with the zoom as I was always used to the more immersive that they give but both give equally good viewms to my eyes.

Stephen