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Usefulness or otherwise of 20x fixed eyepiece (Nikon ED50 related) (1 Viewer)

mulligatawny owl said:
I'm not unhappy with the brightness of the 20x at all but even on a sunny day I can tell my SE's and HRWP's are brighter.
Click to expand...

That's what I wondered about, in theory on a sunny day, you should not feel a clear difference in brightness (your eye pupille being smaller then than both the 2,5 mm exit pupille of the Scope and the 4 mm of the 8x32). Maybe the more relaxed two-eyed view gives that impression...

As for the cable tie, there is a nice instruction here in the forum: http://www.birdforum.net/showthread.php?t=99084

For stationnary birds, you don't really need this. But for birds on the sky, the cable tie works wonders...
 
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Kevin Conville said:
Yup, similar....


MO,
Your take on the ED50 w/ the 20xw doesn't jibe with mine, at all.

I find a tripod steady 16x or 20x yields tremendous detail over a handheld pair of bins.

As I said in the other thread, I think the 20xw is a charmer on the ED50.
Click to expand...

Hmm, tis starting to make me wonder if I have got a faulty eyepiece or faulty eyes. More likely its a difference in individual perceptions and definitions and styles of birding.
But of course I can see what you say is obviously correct. If for example I look at some very small print at a distance, and I've done this tripod mounted, I can read the small print very easily with the scope and cant make out a thing with either binoculars. But, and I suppose this is the point, birding for me is a more holistic thing than just picking out more details in feathers say ( maybe that is something I'll come to appreciate more)
So yes, the 20x on a tripod shows much more detail at say, mid range, than binoculars, but at that range i still much prefer ( as I see it) the holistic and relaxed view of binoculars. And at longer range where I envisioned the scope to have its use for me I'm not so far finding it much fun or help to use over binoculars in regards to simply IDing birds.
 
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It's starting to read like you have the wrong scope, but I'll come back to this.

If you are comfortable ID'ing birds at the distances you mostly encounter them with your bins and the scope is not improving this much, then why carry the scope? Your interest seems to be slanted more towards identification rather than the aesthetic.

If you want the scope to have much more reach than you're getting with the ED50 and MC 20w, then I'd recommend going straight to an 80mm+ scope and a high power (likely zoom) EP.

27x or even 40x might not be sufficient (ED50), and with the larger scope 50, 60, or 75x are quite doable. Nikon has 2 EPs that'll get you 75x on the ED78/82.

I do predict :smoke: however that if you sell that ED50 with the 20x now, that someday you'll regret it.
 
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As it's just been a week you have the scope, best give it some more time. Either you will start to like it, or you'll find out whether you don't need a scope at all or actually need sth, bigger...
 
Kevin Conville said:
It's starting to read like you have the wrong scope, but I'll come back to this.

If you are comfortable ID'ing birds at the distances you mostly encounter them with your bins and the scope is not improving this much, then why carry the scope? Your interest seems to be slanted more towards identification rather than the aesthetic.

If you want the scope to have much more reach than you're getting with the ED50 and MC 20w, then I'd recommend going straight to an 80mm+ scope and a high power (likely zoom) EP.

27x or even 40x might not be sufficient (ED50), and with the larger scope 50, 60, or 75x are quite doable. Nikon has 2 EPs that'll get you 75x on the ED78/82.

I do predict :smoke: however that if you sell that ED50 with the 20x now, that someday you'll regret it.
Click to expand...

I'd say my interests are slanted toward the aesthetic with the bins and toward simple IDing with the scope where the bins don't have enough reach.

So,I suppose to get back to the original point ( I AM getting a bit befuddled I have to admit- I blame it on the strong painkillers I'm taking for a cracked rib)
um where was I? o yes, I'd like a scope small enough to fit in a rucksack that I can whip out on the occasions when I can't identify bird with my binos. I know I'm not gonna get a small scope with long range seawatching abilities in my rucksack but for hides and estuaries and such at not vast distances I was hoping the 20x would be enough, I'm just, so far anyway, finding it not really worth bringing the scope along as I havent yet found an instance where the 20x can ID a bird when the bins can not.

Sooo I reckon either the zoom or the 27x will do the job. Simples. :)

But I reckon I'll keep the 20x too .
 
Well, I also find 20x isn't ideal in a scope. Many years ago I used a Kowa TS1 (shows how old I am ... :) ) with 20x WA, 25x and 40x. I mainly used the 20x in woodland, and usually to look at some feather detail I couldn't see through my binoculars or to study a bird's behaviour. That's where a scope is almost essential as holding your bins steady for 15 minutes or more does get a bit difficult, even with a lightweight pair. There weren't many situations where I got an ID with the scope I couldn't have got with the bins.

Everywhere else I used the narrow 25x. The (really rather small) difference between 20x and 25x made all the difference to me so no, 20x doesn't work for me. These are all personal preferences, of course, just like I don't get on well with 30x or 32x WA eyepieces because of the narrow depth of field.

I've also got a Nikon ED50 as my second scope. With it I use the 16x and the 20x (only really in woodlands) and the old zoom (13-33x) for more general birding. In case I suddenly need more magnification with the 16x or the 30x I use a 3x booster. The image quality isn't very good, the ED50 is just too small for 48x/60x, but sufficient to get an ID quickly.

If I were you I'd probably get a bigger scope or use the Nikon zoom with the ED50. I think a bigger scope like the Nikon EDIII or one of the 65mm scopes is probably ideal, they're not too heavy but give you access to 50-60x. For identification, especially at the coast or at lakes, you really want an easy and quick way to use 40x or more.

Hermann
 
My thoughts:

Are you saying that you can already ID distant birds with your bins? That could be true, in which case, you shouldn't use the scope (for ID). Scopes are useful for ID of distant birds that can be spotted, but not IDed at 8x, and cannot be approached. The existence of such birds is a basic prerequisite for a scope to be useful for birding (narrow sense).

25-30x has been the mainstay of scoping for a long time. That magnification nicely complements 7x or 8x bins for seeing distant and otherwise unidentifiable birds on lakes, marshes, etc. I have the 27x on my 50ED and the 30x on my 78ED, so whichever scope I take, I get approximately the same predictable "scope view" that I know how to use productively in the course of my activities (i.e. I can plan my hike, vantage points etc based on what I know that magnification can and cannot do for me, just as I know what my 8x binocular view can and can't do--I know when I see a bird whether to start lifting the bins to my eyes, or instead start off by running towards it).

There isn't much difference in mag between 20 and 27x, so I don't think that comparison will impress you, but the marginal difference in comparison bins might be enough to make the bread and butter ID domain of your scope larger and different enough from your bins that its utility (or lack thereof, depending on the birding situation) obvious.

Get the 27x and find some birds that are too far away to ID with your bins.

--AP
 
Hermann said:
I've also got a Nikon ED50 as my second scope. With it I use the 16x and the 20x (only really in woodlands) and the old zoom (13-33x) for more general birding. In case I suddenly need more magnification with the 16x or the 30x I use a 3x booster. The image quality isn't very good, the ED50 is just too small for 48x/60x, but sufficient to get an ID quickly.
Click to expand...

Can you explain a little more about use of boosters ... sounds interesting ... (if a 2x were available would that work with the 27x I wonder?)
 
In the thread in the Binoculars section where I argue that a 7x + a 10x binocular are better than one 8x, I explained that if you use 6x or 7x for short to medium distance birding, you will only have to take a few steps forward to get the same image size that you get with an 8x.

But for longer distance, magnification is king. If you barely see a bird's details at 300 meters with a 30x scope, you'd have to move 100 m ahead to get the same image size with a 20x. Sometimes this can be done, more often it can't.
Then again, lower magnifications have their advantages, especially fixed wide angle eyepieces. Good zooms will provide nice brightness at lower settings and take you to where you want in a second. Changing the eyepiece will also happen quicker than you can move ahead towards the bird.

The 16x on the ED50 that Frank praises, is what I'd call a turbo-charged monocular with its own upsides especially for hawking.
The 27x Wides however, make the ED50 a scope! The FOV is barely narrower than the zooms at the lowest setting (47 m vs 52 m/1000 m), so except for the brightness in dusk it makes everything the 13-30x can do, just easier, wider, more comfortable and more mind-blowing!
 
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FWIW on a purely theoretical basis, max visual resolution is ~22x on the ED50 and magnification above that is "empty", i.e. no more detail gets resolved, just gets bigger. The 20x Wide MC is the best eyepiece for the ED50 for maximizing detail while still maintaining image brightness if like most humans, your pupil does not dilate smaller than 2-2.5mm in bright sun. The 27x always yields a dimmer image. Whether you notice it or not....
 
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Alexis Powell said:
My thoughts:

Are you saying that you can already ID distant birds with your bins? That could be true, in which case, you shouldn't use the scope (for ID). Scopes are useful for ID of distant birds that can be spotted, but not IDed at 8x, and cannot be approached. The existence of such birds is a basic prerequisite for a scope to be useful for birding (narrow sense).


Get the 27x and find some birds that are too far away to ID with your bins.

--AP
Click to expand...

I suppose for distant birds I have learnt to rely on small clues like a flash of colour, a distinctive shape or the overall jizz of a bird. That's why I love ultra sharp porros like the SE and the HRWP as they are so sharp at a distance.
Obviously beyond a certain distance I cant ID a non distinct bird with bins though, for this I need more reach and 20x just seems a touch short to make it worthwhile for those rare occasions when a bird is at just the right distance that 20x will clinch the ID and 8x wont. Whereas In just this past week I've had a number of instances where neither the bins nor the 20x scope could ID the bird.
Saying all this though, I have just had the most enjoyable time with the scope leisurely watching a carrion crow bathing and preening, it was fascinating to see in detail the nictitating membrane repeatedly drawn across the eye as it bathed. I certainly wouldn't have seen that sort of detail with binoculars.
 
mulligatawny owl said:
Saying all this though, I have just had the most enjoyable time with the scope leisurely watching a carrion crow bathing and preening, it was fascinating to see in detail the nictitating membrane repeatedly drawn across the eye as it bathed. I certainly wouldn't have seen that sort of detail with binoculars.
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Exactly, I also felt this when starting with my first scope (ED50 btw), it adds another level of experience and enjoyment to birding, besides the mere IDing of far away blobs.
Two weeks ago I bought a big scope, and looking at a blue tit 10 m away with 50x magnification is just amazing (though not really required for the ID).
 
I have a 13-40 zoom and a 20x wide MC eyepiece for my ED50 and much prefer the 20x. I did briefly own a 27x (for about 24 hours) but I don't remember the extra magnification being very dramatic. That was a few years ago so I can't comment too much on the experience. I swapped it for the 20x for digiscoping.

I don't think looking through a scope with one eye will ever feel as relaxing or natural as using binoculars and I find it much less tiring to use both my eyes. I carry my ED50 in a Grippa case and it find it very useful if I want a closer look at something. I wouldn't consider using it like that for extended viewing though.

Ron
 
RJM said:
FWIW on a purely theoretical basis, max visual resolution is ~22x on the ED50 and magnification above that is "empty", i.e. no more detail gets resolved, just gets bigger.
Click to expand...

You've stated this in the past, but to put it simply, it doesn't accord w/my experience w/the 50ED (and the explanation is not that I have poor visual acuity, in which case a bigger but no more resolved image would certainly be useful) and it seems a very pessimistic limit. Please explain.

--AP
 
THEORETICAL optical math Alexis. Your practical observations can differ.

Avg. limit of human visual resolution = ~1 arc minute = 1/60= ~.017 degrees of arc
Scope Aperture = 50mm
Rayleigh Limit = 2.79 arc seconds = 2.79/3600 = .000775 degrees of arc
Max visual mag needed = .017/.000775 = 21.94x

Now if your acuity is worse than average, say 2 arc minutes then ~43x is your magic number (but will be offset by the dim image).
If you are fortunate to have Superman's eyes, say 0.5 arc minutes, then ~11x is your magic number. Got it?

In the end, it is basically all fun with numbers trivia. All that counts is our individual experiences.

Interesting that the eyepiece selection for this scope limits mag range to 13-40x, isn't it? Guess those engineers at Nikon like to play it safe!
 
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Rick,

Can you clarify for me why someone with "superman's eyes" gets the most out of the scope at 11x while someone with poor eyesight can get the most out of the scope at 43x? That seems to be the reverse of common wisdom unless I am reading it incorrectly. If someone has excellent eyesight then I would think they would be able to pull more detail out of the image at a higher magnification assuming the scope is able to provide that detail.
 
Hmm, Henry is better at teaching aids but let me try this scenario Frank.

I have perfect vision and can read the newspaper at normal distances.
You suffer Presbyopia and can't read the paper at all. You go to the drugstore and buy +2.5x magnifiing reading glasses. Now you can see what I see.

Make sense now?

Keep in mind you could get the same mag limits if you have perfect vision and the scope does not have the perfect optics as indicated by the Rayleigh value. Reality is somewhere in between most times...less than perfect optics and less than perfect vision usually means folks see more at higher mags. The "gotcha" to using more mag is the real limitations on acuity as exit pupils get really small, like less than 2mm for our purposes.

It's all fun with numbers BUT the Rayleigh limits and human visual acuity limits are really more than just theory.
 
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Some of what I have read in the past you would need 80x to see the highest resolution of 50mm lens. Interesting topic.

What is useful resolution? In my use of this the Nikon ED 50 it has been up to 40x and I have had 2 samples to test. One lent to me and one I bought. I found both excellent.
 
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