FSIIIED High Magnification

[pluvanut]

Nikon 60 III ED is a fantastic little scope

small
light
great image
very portable indeed.

These are the reasons I use FSIIIED, but I could use some help:

It took me a while to realise that ED was what I needed to have the extra 'edge' in the image that I had with the bins (8x32 SE); buying ED solved that problem, or close to it.

I have no experience with high mag. scoping as I use the 'scope on a shoulder pod almost all of the time, simply on grounds of portability/mobility (all fits in small rucksack, with bins and lunch). 30xW is my favourite eyepiece and almost always in use, though I also have 20 which is sometimes handy in rough/dull weather. 30x is just about manageable from the shoulder and great in hides, where the 'pod becomes a bipod on the bench - more than steady enough for higher mag, which would be nice to have on occasion.

At Bird Fair over the weekend I spent some time looking in good light through 60xW (probably preferred to keep wide FOV) and the 20-60 zoom; good as they obviously are, neither really seemed produce the same image quality as the 30. The image is twice as large, obviously, but like ED/nonED comparison loses out in image 'information' compared with the 30xW. Casts serious doubt on whether it is worth springing the £200ish.

I guess 50% reduction in light transmission will always be significant and a look through the ED82 seemed to confirm that.

And now to the point - is 60x a worthwhile proposition on a 60mm scope? 45 seems hardly worth having.

Comment and experience please.

[Dave B Smith]

I have the FS III ED also and really like it. When I bought it I checked the Nikon write up and they recommended the 20-45 X for this scope, the understanding that there was not really enough light for the 60X. I have heard that image quality is actually better in the 20-60X eyepiece (just a better optic) than the 20-45X though.

I'm considering getting the fixed 30XWA. I don't think the little bit of extra magnification that you get with the zoom to 45X would be enough to justify this zoom.

[pluvanut]

I have the FS III ED also and really like it. When I bought it I checked the Nikon write up and they recommended the 20-45 X for this scope, the understanding that there was not really enough light for the 60X. I have heard that image quality is actually better in the 20-60X eyepiece (just a better optic) than the 20-45X though.

I'm considering getting the fixed 30XWA. I don't think the little bit of extra magnification that you get with the zoom to 45X would be enough to justify this zoom.

Hi Dave,
Thanks for helpful info, maybe the 30xW is simply close to optimimum for the 'scope?

[Hermann]

And now to the point - is 60x a worthwhile proposition on a 60mm scope? 45 seems hardly worth having.
Comment and experience please.

I've been using the EDIIIA for several years now with the 20-60x zoom as my main eyepiece. The excellent 30x WA doesn't work for me because I feel the depth of field is too small for general birding; I only use it for stuff like raptor watching where a wide field of view is of the utmost importance. Before that I used the EDIIA with "old" 20-45x, which is, by the way, not a bad eyepiece at all, especially not the new version with multicoating.

I find I use magnifications of up to 60x quite regularly, and more than once the possibility to get above 45x has proved important in getting an identification. Alright, the image quality at very high magnifications suffers when you compare it to the views through one of the big scopes. But you still see more than at, say, 30x, no matter how good the Nikon 30x WA is. In fact, I think the possibility to get up to 60x with the Nikon quite easily is one of the major advantages compared to the small Leica and the small Zeiss.

Hermann

[Swissboy]

I have just come back from an extended trip to North America, only part of which was for nature watching. Under these conditions, the handy small FSIIIED was close to ideal. Particularly as I matched it with a carbon tripod and a lightweight head (Novoflex DinO). Thus, the scope came along even for use in the bus at Denali NP in Alaska. My only gripe was (and still is) the narrow FOV of the zoom eyepiece. But I gladly took advantage of the full range of magnifications up to 60x under good light conditions. The range above 45x was particularly welcome for a better look at distant wolves and a Gyrfalcon family. Nevertheless, I have now ordered a 30x eyepiece which should come in handy with its wider FOV.

Robert

[Jay Turberville]

I find I use magnifications of up to 60x quite regularly, and more than once the possibility to get above 45x has proved important in getting an identification. Alright, the image quality at very high magnifications suffers when you compare it to the views through one of the big scopes. But you still see more than at, say, 30x, no matter how good the Nikon 30x WA is. In fact, I think the possibility to get up to 60x with the Nikon quite easily is one of the major advantages compared to the small Leica and the small Zeiss.


I recently modified my digiscoping calculator to include the human eye. Assuming diffraction limited optics, and "normal" vision, a 60x on a 60mm scope is pretty much the limit. At this limit, detail may be resolved, but probably won't be resolved with a lot of contrast since you are right up against the theoretical limit where the scope begins to resolve less detail than the eye can see. In fact, considering that the scope probably isn't diffraction limited, some of the real benefit is probably not in resolving more detail, but is in making the detail that is resovled somewhat larger and easier to see distinguish.

People with eyes that can resolve more detail than nomal may see less benefit at 60x and people with below normal resolving capabilities may experience more benefit at 60x.

And this means that at 30x, the scope is resolving almost twice as much detail as the eye can see. The image pops because the image that is delivered within the eye's resolving ability is very contrasty since it is far from the scope's limit. But this does mean that more detail could be revealed by using higher magnification.

So theory seems to follow observation here. 60x can be useful but won't necessarily be as "pretty" as lower magnifications. This is probably why Nikon recommends the 15-45x zoom. They don't want customers complaining that their scope is dull at 60x.

[pluvanut]

Hi Dave, Hermann, Robert, Jay,
Thanks to all for the above education; field experience and an elegant piece of theory alike, which for once seem congruent! All adds up to rational, real world compromise as ever.

Seems as though the 30W + 20-60 would be a good set; just when I was thinking my £200 was safe.... now if I had an ED 82 as well........

Enjoy the 30x Robert/Dave, like Jay says - a very 'pretty' view.

Jay - my understanding of diffraction is something that occurs when light passes closes to a sharp edge like a camera lens iris, for instance, causing a some scatter.
Your explanation of diffraction limitation seems to imply something else, like (guess) the same thing happens at glass/air interface?
Can you explain more about 'diffraction limitation' please?

[Jay Turberville]

Your explanation of diffraction limitation seems to imply something else, like (guess) the same thing happens at glass/air interface?
Can you explain more about 'diffraction limitation' please?

Nope. It is the very edge effect that you speak of. The net result of this effect is that it defines, by the very nature of light, the best possible result that a given lens diameter and focal length can give. In other words, the f-ratio sets a limit to an optic's resolving power. This limit is caused by the edge effects of the optical aperture. The larger the relative aperture, the less the edge effect is a factor.

Optics don't really form dots. They form dots with concentric circles of diminishing brigthness. These dot sizes and pattern shapes (the shape changes with "obstructed" optics) represent a limit on what can be resolved by the optic.

My calculator uses a simple formula that uses the wavelength of green light and the final effective f-ratio. The calculated results represents a "best case" scenario. The real results from a scope are usually worse because birding optics are probably not diffraction limited (though the best ones are probably close).

There are tons of references on this (most based on astronomy) that you can find via a web search.

[scampo]

Hi Dave, Hermann, Robert, Jay,
Thanks to all for the above education; field experience and an elegant piece of theory alike, which for once seem congruent! All adds up to rational, real world compromise as ever.

Seems as though the 30W + 20-60 would be a good set; just when I was thinking my £200 was safe.... now if I had an ED 82 as well........

Enjoy the 30x Robert/Dave, like Jay says - a very 'pretty' view.

Jay - my understanding of diffraction is something that occurs when light passes closes to a sharp edge like a camera lens iris, for instance, causing a some scatter.
Your explanation of diffraction limitation seems to imply something else, like (guess) the same thing happens at glass/air interface?
Can you explain more about 'diffraction limitation' please?My son has the ED82 with 30xW and 25-75x zoom. He had a choice between that and the Swaro 65HD - which he had been using for a year and a half, but preferred the Nikon.

I think the Nikon 30xW is a birding eyepiece par excellence; the zoom has the same superb faithful colour, brightness and sharpness - but, as Robert has suggested, although noticably only at the lower magnifications, its field of view is narrower than other top scopes. It's for that reason I like my Zeiss which makes all other zooms seem narrow by comparison, but in my heart, I still think the utterly vivid faithfulness of the Nikon image tends to put all others in the shade for the view it gives. When will Nikon bring out a wider zoom eyepiece, I wonder? Or Zeiss one to match the Nikon for faithfulness of colour? I wonder what the manufacturers themselves think.

[pluvanut]

My son has the ED82 with 30xW and 25-75x zoom. He had a choice between that and the Swaro 65HD - which he had been using for a year and a half, but preferred the Nikon.

I think the Nikon 30xW is a birding eyepiece par excellence; the zoom has the same superb faithful colour, brightness and sharpness - but, as Robert has suggested, although noticably only at the lower magnifications, its field of view is narrower than other top scopes. It's for that reason I like my Zeiss which makes all other zooms seem narrow by comparison, but in my heart, I still think the utterly vivid faithfulness of the Nikon image tends to put all others in the shade for the view it gives. When will Nikon bring out a wider zoom eyepiece, I wonder? Or Zeiss one to match the Nikon for faithfulness of colour? I wonder what the manufacturers themselves think.

Hi, Steve
When? All too often it seems, just after I buy their existing product at full price! Doesn't do to think like that though, does it?

Agree re the 30xW, it's a real pleasure to use; also re Nikon image quality.
I think I'm convinced, compromises included, that there is enough benefit to be had from the 20-60.
The 20 fixed I have at present doesn't have as much FOV as the 30, although (according to Nikon figures) a bit more than than the zoom at 20x.
Given that low mag is in effect inherently 'wide', finding the bird isn't too much of a problem. Helped also by a straight scope (used on a shoulder pod) being easier to aim much of the time. Anti-social at 'meets' though, so now I need an angled scope, an ED82.........

[pduxon]

Hi, Steve
When? All too often it seems, just after I buy their existing product at full price! Doesn't do to think like that though, does it?

---
Anti-social at 'meets' though, so now I need an angled scope, an ED82.........

Yup can empathise with the first point!!

Uh ED78 off W/Express Pluva? You can get it without the lens!!

[scampo]

Hi, Steve
When? All too often it seems, just after I buy their existing product at full price! Doesn't do to think like that though, does it?

Agree re the 30xW, it's a real pleasure to use; also re Nikon image quality.
I think I'm convinced, compromises included, that there is enough benefit to be had from the 20-60.
The 20 fixed I have at present doesn't have as much FOV as the 30, although (according to Nikon figures) a bit more than than the zoom at 20x.
Given that low mag is in effect inherently 'wide', finding the bird isn't too much of a problem. Helped also by a straight scope (used on a shoulder pod) being easier to aim much of the time. Anti-social at 'meets' though, so now I need an angled scope, an ED82.........If you only lived closer, you could borrow ours for a couple of weeks! I think you'll find it suits the EDIII quite well. I'm never fully satisfied with the maximum magnification of any zoom - I've used Nikon, Leica and Zeiss - the depth of focus is so very tiny and all atmospheric and heat haze is magnified. That said, just occasionally, on a clear day, I think - this is really good! You'll feel the same about the Nikon zoom when you get it, but you'll not be able to put the 30x in its case for too long, I reckon.

I don't know if things have changed but the price at In Focus was the lowest when we bought ours a year ago.

[gorank]

just remember, when you are comparing nikon eye pieces, that the 30x for the ED82 is 24x for the FSIII...and the 30x for the FSIII is 38x for the ED82...but I guess that is pretty clear for most..=)

[scampo]

It is now, Gorank!

((-;

[pluvanut]

If you only lived closer, you could borrow ours for a couple of weeks! I think you'll find it suits the EDIII quite well.

Appreciate the generous thought, Steve, but I think I'm sold on the 20-60 anyway. Always was a sucker for new gear and we always want further, clearer, more detail........



Uh ED78 off W/Express Pluva? You can get it without the lens!!

R U Quackers?
Still struggling with the price of the zoom eyepiece I don't have yet, mind you an ED78 at that price is a real steal and Jay says a good big 'un will always out-resolve a little 'un... Arrrgh! |:S|

[pduxon]

R U Quackers?
Still struggling with the price of the zoom eyepiece I don't have yet, mind you an ED78 at that price is a real steal and Jay says a good big 'un will always out-resolve a little 'un... Arrrgh! |:S|

No Quackers is another member - whoops thread deviation, thread deviation!!!

Right back on track, yeah get the zoom!! Phew!!