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Old Friday 3rd July 2015, 23:06   #1
zzffnn
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Binoculars as microscope - Pentax Papilio 6.5x21 vs Minox BF 10x42

It is my pleasure to join this great forum here. I am trying to buying another binocular as microscope and need your kind help.

I currently have the Pentax Papilio 6.5x21 and like it as a microscope looking at insects. I want more magnifications (~10x) and brighter/bigger objectives, without interrupting natural behavior of insects (I have many good real microscopes for unnatural “manipulation”, if I want to do that).

Will Minox BF 10x42 provide more magnification and resolution, in theory (I am guessing not significatnly, if my calculation is correct)? I understand that Penta Papilio 6.5x21 has near focus of 0.5 meters, while Minox BF 10x42 has near focus of 1.2 meters.

I know Pentax Papilio has a 8x21 version and in macro mode its magnification is around 10x, but I want brighter/bigger objectives and 10x. I do not mind using binoculars on mini tripods.

Occasionally I use the Pentax for faraway objects too and it works fine for me, though that is not the main reason I bought it for (my main use for Pentax is close observation of insects and museum displays). I have an old Russian Red Star 10x42 for faraway objects, but its close focus is not usable as microscope.

Please kindly comment. You do not have to have hands-on experience with either binoculars – I think all you need is some decent understanding of optical theories and math. Thank you very much.

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Old Saturday 4th July 2015, 07:31   #2
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I haven't used binoculars a great deal for looking at insects but just considering a couple I own I'd say my 7x36 at 4ft is a much better than my 10x42 at 6ft for it's wider, steadier view and better stereopsis. I was trying to get a good look at the mites on the back of a queen red tailed bumblebee yesterday and wished I'd had a Papilio with me instead of ZenRay Prime 10x42. The quality of the view is considerably better but distance is the killer.

Generally the Minox BF is not a binocular I would recommend for birdwatching but on the other hand I can't recall many that will match 1.2m let alone better it. Wouldn't getting a stereoscopic view be impossible at that range without the converging optics of the Papilio? I would have thought a good monocular or gallery scope might be a better bet?

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Old Saturday 4th July 2015, 14:37   #3
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. Hi there zzffnn,
Strictly speaking you are not talking about a microscope, rather a macro scope.

There are many monoculars that have been produced over the last hundred years, where they can be adapted to macro use, I think with an additional lens on the front. You may be able to do this by screwing in a close-up lens or attaching it to a monocular. Some of these are very low price and work quite well. They usually have a device for working at the correct distance as you can only work close-up with these with the adapter in place when they have a limited focus range.


I have the Papilio II 6.521 and I find that it is very nice at close distances. I also get very good stereo images.

I suppose another way would be to look through the viewfinder or at the screen of a compact camera, as these focus very close.

If the insect was stationary I suppose that you could use a stereo viewer that is used for stereo photographs. These have some focus range. Also a World War II stereo viewer that was used for examining aerial photographs.

I have the Glanz close up monocular, but I think it is 7x. There are several other similar devices, maybe some are 10 times.

P. S.
From memory some of these work by focusing the front in addition to the normal focus at the back. This seems to provide a great focusing range.
There was a similar device in a very early Sigma lens for focusing very close using a camera. It has a Q in the name, from memory.

Last edited by Binastro : Saturday 4th July 2015 at 15:06.
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Old Saturday 4th July 2015, 15:25   #4
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. In addition there was a few years ago the mini spotting scope and microscope set by Opticron.

It consisted of 820 monocular with 30 times microscope conversion.
1530 spotting scope with 45 times microscope conversion.
2530 spotting scope with 75 times microscope conversion.
Also a mini tripod.
In addition the adapters worked very well as a lupe.
All of this in a very nice fitted case.
The instruments were gold and black

Sherwood's had these at clearance for 25.

I think that the Glanz is perhaps 742, but I'm not sure.
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Old Saturday 4th July 2015, 15:36   #5
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Thank you Gents for your kind comments.

I do not really need a 3D view. My reason for prefering bino over mono is the lack of eye strain.

I do realize that monoculars can focus closer and are much easier to tether to camera. I can always record videos and view later on, I guess.

I did see a pair of Orion 10x42 monoculars that can focus at 0.5 meter: https://www.amazon.com/gp/aw/d/B002T...94&sr=8-5&vs=1
What do you think of that one? Some Mono's can even focus at 0.3 m.

Alternatively, as Binastro pointed out, I can use close-up camera lens. I do have a reversed mounted lens that provides about 2x at about 5 cm of near focus. I just have to watch out and protect my lens from insects and dust, when going with this approach.

I am not sure stereo viewers would work for me. I wear strong eyeglasses. I found few of those available currently and they did not see to indicate magnification. Also they do not seem to work with camera (binoculars can work with camera, though adaptation is not convenient).

If insect is stationary (i.e., dead/no natural behavior to observe). I guess I can put it under a dissecting microscope or my biological microscope equipped with 1x or 2x NA 0.05 objective and 6x eyepeices.

I will look into Opticron , thank you Binastro. I have been to their web site to look at their gallery scope, but somehow I missed the convertibles what you mentioned.

David, is there a reason why you ususally do not recommend Minox BF 10x42 for birding? Chromatic aberration? We saw some tropical birds at zoo yesterday with the Pentax Papilio, it was fun! I am not a critical birder.

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Old Saturday 4th July 2015, 16:03   #6
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I think that the Opticron set is discontinued, but it might be available under another name or for sale second-hand.
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Old Saturday 4th July 2015, 16:05   #7
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Binastro,

Is this the Opticron 8x20 convertible that you mentioned: http://www.opticronusa.com/Pages/gallery_scope.html

I am curious if the "micro stand" contains any lens (like those you mention in your first post here). If not, that means the 8x20, when focus at 0.3 m, provides 24x by itself?

The stand may interfere with insect behavior, but I guess I can use it on tripod/portable focusing rail (without the dome stand).

Would the Orion 10x42 monocular (0.5 m focus) that I mention work the same way, if I add a front lens for more magnification? Where can I find such adapter lens (I can Google it, but not sure what keywords to use).
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Old Saturday 4th July 2015, 16:16   #8
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. The Opticron close focus monocular in post 7 is completely different to the set that I have. But that one should work well. If you contact Opticron, they are a very good company and they will tell you whether it has a lens or not. I suspect that it does have a lens for macro work.

The set that I have has a lens in it, which is excellent on its own as a magnifier. It has a clear plastic part about 2 inches long and the whole adapter is almost 4 inches long.

Canon have a vastly expensive special lens for macro work and I think that Minolta did as well. I also used to use reversed lenses for close-up work. I think that if you use a 200 mm macro lens you get a long working distance. You can also use the lens on the camera and then a reverse second lens attached to the front of the camera lens.
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Old Saturday 4th July 2015, 16:20   #9
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. The Orion 1042 waterproof monocular in your link seems to be very useful and not expensive. I haven't tried that although I do have a zoom monocular, but optically it is poor.

The zoom monocular is called Forest optics 10-2542 waterproof zoom near focus 20 inches. It looks similar to the Orion 1042 binocular. In fact there were two Forest optics monoculars at a sale price and I chose the zoom one. I should have chosen the fixed focus as I'm pretty sure that would be better optically.

The zoom monocular has partly multicoated and partly single coated surfaces. I don't see any uncoated surfaces.

I think that the Orion monoculars and the Forest optics monoculars are almost identical and come from the same factory and just have different names on them.

P.S.
At 10x or 12x the zoom monocular can be used with glasses, at 15x and 25x not.
The apparent field is small at 10x good at 25x.

Last edited by Binastro : Saturday 4th July 2015 at 16:42.
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Old Saturday 4th July 2015, 16:41   #10
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Thank you Binastro.

I am aware of the expensive Canon macro lens (it provides only 5x if I remember correctly) and the reverse lens+tele lens trick. I do not have tele lens though. But I will think about it more. Maybe I should buy a tele lens after all.

Was just wondering if I can get better view more comfortably from binos. Which was why I asked about the Minox BV 10x42. But their 1.2 m focus is probably still too far for macro observation.

The Orion 10x42 monocular is looking better.

Another approach that I can think of is to adapt a binocular dissecting microscope. Take the head of stand and put it on tripod + portable focus rail. The draw back is limited focus distance (5-14 cm for most, 14 cm ones are usually expensive at >$500) and limited light gathering ability due to small objective(s).

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Old Saturday 4th July 2015, 18:21   #11
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. Although I said that the 10-2542 waterproof zoom binocular was not very good optically. This was when I tried it for astronomy and general use.
However, I just tried it for macro use at 25 times, which I presume is fairly accurate.

The closest focus that I can get, being longsighted, is 75 cm from my eye or 57 cm from the front of the monocular. It is impossible to hold it steady, so I think that one would have to use a tripod. I don't need glasses.

Looking at a glass of water at the closest distance, the bubbles are very well seen.

But if somebody needs to wear glasses, then the field is much restricted at 25 times. But maybe with an exit pupil of around 1.7 mm glasses are not needed?. It is possible that this is a useful instrument, although the 1042 may focus closer and probably has better optical quality and a wider field of view.
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Old Saturday 4th July 2015, 18:32   #12
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i have had for a numbe of years, the Orion 10x42 monocular with 20" close focus. It also has a tripod hole, and mine came with a neck lanyard the screwed into that hole. Actually does not get alot of use, but it lives in my car glove box, for the quick pull-over-look thing. For its price it is actually quite good, On my one the optical quality is about on a par with my version one Papilios.
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Old Saturday 4th July 2015, 19:12   #13
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Thank you Jay and Binastro.

I will give the Orion/Forest Optics a try. It looks like the same product is also branded as Barska in USA.

Thank you Jay. Your comparism between Pentax Papilio and the Orion is helpful to me. Do you think the apparent view size (when using Papilio with only one eye) and eye relief are also comparable? View field size and eye relief of Papilio II 6.5x is just enough for my eyes with glasses on - I probably won't be able to take anything smaller/shorter, unless I remove my glasses.

Binastro, since you also have the Papilio II 6.5x, would you please also compare it with your Forest Optics zoom, in terms of apparent view field size (when using Papilio with only one eye) and eye relief? I read that Orion's zoom model has more CA than the fixed 10x model, but I can probably live with that if the amount is not huge. Is the zoom continuous from 10x to 25x (15x, 20x possible?) or are there only two discrete zoom levels at 10x and 25x? I do appreciate higher magnification for macro observation and can probably live with less optical quality.

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Old Saturday 4th July 2015, 20:15   #14
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Quote:
Originally Posted by zzffnn View Post
T...Jay. Your comparism between Pentax Papilio and the Orion is helpful to me. Do you think the apparent view size (when using Papilio with only one eye) and eye relief are also comparable?
I think the FOV on my 8.5x Papilio is 6 degrees, and the FOV on the Orion is like 5.8-5.9 degrees. Eye relief on the Orion is listed i think, as 17mm, and it seems better to me than the Papilio.
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Old Saturday 4th July 2015, 20:16   #15
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Quote:
Originally Posted by zzffnn View Post
David, is there a reason why you ususally do not recommend Minox BF 10x42 for birding? Chromatic aberration?
Sorry, I hadn't realised there is a new version of the BF out this year which I haven't seen. I thought the old one had a rather soft and anaemic view with a fair amount of CA, so I do hope the new model is significantly better.

David
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Old Saturday 4th July 2015, 20:52   #16
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zzffnn,
It will probably be tomorrow before I can compare the Papilio and the zoom monocular.
The monocular works okay, but focusing is a bit rough and there is a lot of twiddling from near focus to far focus.
I recall that the 6.521 Papilio II had a similar close focus distance to the zoom monocular at 25 times.
Looking at the computer screen now there is very little difference in close focus distance throughout the range from 10 times to 25 times. Looking at the computer screen the resolution is okay although there is detectable chromatic aberration even at close distances.
The magnification is continuously variable from 10 times to 25 times.

From memory there was chromatic aberration and also softness of the image with the zoom monocular in normal use, but I'll try it again.
I have the zoom monocular on my desk, but I generally pick up the Kowa 2050 spotting scope, which lives next to it, as a better option. But the 2050 has a very long close focus distance.

. The zoom monocular also has a lanyard that screws into the tripod socket.

Last edited by Binastro : Saturday 4th July 2015 at 20:56.
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Old Saturday 4th July 2015, 22:08   #17
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.Looking at this computer screen and comparing the 6.521 Papilio II and the zoom monocular I get the following.
With the rubber eyecup folded on the zoom monocular and the Papilio eyecup screwed down and using just one eye, I can see the whole field of view with the Papilio. Similarly, with the zoom monocular at 15 times or even 20 times. However, this is a struggle with the monocular as I have to push my glasses back as far as possible to my eyes. And this is using my smallest glasses, which are my reading glasses, which may have the shortest distance from the lens to my eyes.
You may have to accept a restricted field if you use the monocular at 15 times or 20 times. Whichever way you need to have small glasses. Or maybe at these high magnifications you could do with out glasses?

As to the field of view. Looking at the computer screen the real field of view with the zoom monocular at 15 times is about one third of the field of the Papilio binocular at the same screen distance.

With the Papilio, the shortest distance is quite a bit less than with the zoom monocular, mainly because the zoom monocular is about 3 inches longer than the Papilio. So although the distance to the objectives is similar, one can get closer with the Papilio.

As to the field of view, what do you actually want me to measure?

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Old Saturday 4th July 2015, 22:20   #18
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. Lots of fireworks next door over the last half an hour.
I wonder what they're celebrating? :-)
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Old Saturday 4th July 2015, 22:38   #19
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Thank you very much Gents.

I was asking for apparent field of view (AFOV) and eye relief. Sorry, I was not clear.

I forgot that both Orion and Pentax have their web pages for their products. So there are official specs to compare.

It looks like the Pentax has AFOV of 49 degrees and eye relief of 15 mm.

The Orion 10x42 has AFOV of 59 degrees and eye relief of 17 mm. While the zoom 10-25x42 has AFOV of 24 -33 degrees (I guess 24 degrees for 25x and 33 degrees for 10x) and eye relief of 14 mm.

The numbers match with what Jay and Binastro said.

Decision is difficult for me. The Orion 10x42 will be comfortable for my eyes to use, but its magnification is just a little more that Papilio (which is probably 7.6x when focuses at 0.5 m).

The Orion zoom 10-25x42's AFOV is too narrow for my eyes with glasses, though eye relief looks fine. Probably not very comfortable for me to use, since it is a monocular. The zoom's magnification can be very useful to me though.

I probably have to buy both and use the zoom without eye glasses.

Sources:

Pentax Papilio 6.5x21:
http://m.us.ricoh-imaging.com/sport-...!product-specs

Orion 10x42 monocular:
http://www.telescope.com/mobileProdu.../c/73/8431.uts

Orion 10-25x42 zoom monocular:
http://www.telescope.com/mobileProdu.../73/101451.uts

Newer, Barska and Zhumell offers similar 10-25x42 monoculars. I personally won't go with those, as Newer (at $40, 50% of Orion) seems to have focusing issues, while Zhumell and Barska versions have father near focus at close to 5-6 feet.

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Old Sunday 5th July 2015, 15:20   #20
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. Dear zzffnn,
. With the zoom monocular the apparent field of view is less, much less, at 10 times compared with 25 times.
This is nearly always the case with zoom eyepieces. At the higher magnification the apparent field of view is greater than at lower magnifications, although with the real field of view the situation is reversed.
I might try to get an idea of the apparent field of view.

If you could use the zoom monocular without glasses then I would say it could be useful for you at close focus using the higher magnifications. If you wore glasses you would have real problems at the higher magnifications as the eye relief gets poorer and poorer.

Early this morning, I looked at local buildings and there is quite a lot of chromatic aberration with the zoom monocular. However, it is something that you could maybe live with, especially if you're using it just for close-up work. I think that this is because the optics are fast i.e. the objective lens, and this is not a high quality item. But it is useful.

The zoom monocular is 170 mm long with the eyecup Folded. The Papilio II 6.521 is 115 mm long with the eyecups closed. The zoom monocular is about 2.2 inches longer than the binocular. The distance from the closest focus point to the eyes is about 3 inches less with the binocular.

These zoom monocular weighs 319 g. The Papilio II weighs 295 g.
The zoom monocular has pincushion distortion, at least using it for distant objects.

I think that if you bought the 1042 and the zoom monoculars you would find them useful for the type of observations you mention.
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Old Sunday 5th July 2015, 15:44   #21
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zztop,

I agree with the opinion that a monocular is a better choice than binoculars for 'bugging.' Even though 10x binoculars will give you a larger image, the stereoscopic view will collapse at very close distances, and you will essentially have a mono view, anyway, which is why the Papilio has moveable objectives.

What I use for looking at insects is a microscope pen.

I bought mine from Edmund Scientific years back. The view can be dim depending if I'm in the woods or in the open. Some of the magnifiers on the site listed above have built-in lights.

Brock Le Periplaneta
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Old Sunday 5th July 2015, 16:02   #22
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. Hi Brock,
. Isn't the problem with these magnifying pens that the working distance is very short.
With the Papilio and the close focus monoculars the working distance is much longer.

I don't usually like bugs that much, and they don't seem to like me, at least the flying ones. So I don't know much about looking at them with optical instruments.

For close work instead of using a magnifying pen, I use the terrestrial eyepiece from an old 3 inch refractor or the complete eyepiece tube and optics from Broadhurst Clarkson ship's telescopes. These give a wonderful view of high quality. And they cost nothing because I already have the telescope.
In fact I bought broken old collapsible telescopes for next to nothing, just to get these eyepieces, which are often beautifully made to high standards.
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Old Sunday 5th July 2015, 16:05   #23
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Originally Posted by zzffnn View Post
Binastro,

Is this the Opticron 8x20 convertible that you mentioned: http://www.opticronusa.com/Pages/gallery_scope.html

I am curious if the "micro stand" contains any lens (like those you mention in your first post here). If not, that means the 8x20, when focus at 0.3 m, provides 24x by itself?

The stand may interfere with insect behavior, but I guess I can use it on tripod/portable focusing rail (without the dome stand).

Would the Orion 10x42 monocular (0.5 m focus) that I mention work the same way, if I add a front lens for more magnification? Where can I find such adapter lens (I can Google it, but not sure what keywords to use).
zzffnn,

Leica makes a first rate 8x20 monocular which comes with a screw-on close-up
lens attachment. Full info in link below.

http://www.cameralandny.com/optics/site.pl?page=40390

Bob
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Old Sunday 5th July 2015, 17:17   #24
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Thank you very much Gents.

Binastro, your findings are very helpful to me. Especially that 25x has bigger AFOV. How do you use telescope eyepieces for close work though? I imagine they will also have very small working distances, which may disturb insects?

For high quality macro (and very small working distance), I use biological microscopes with a 1x objective (NA 0.05, which is high resolution for 1x) and 6x eyepieces. But subject cannot move much (preferably immobilized) in that case.

Brock, your comment on stereoscopic view collapsing at close distances makes sense to me. The microscope pen won't work for my (poor) eyes though. Their AFOV is simply too small. I have a portable microscope with eyepieces of that size and I cannot use it for more than a very minutes.

Bob, thanks for mentioning another option. I don't have another $399 for a 20 mm objective though. For 20mm objectives, I am happy with the Papilio II 6.5x21. I am looking for 42mm objective this round for >=10x.I know coating and Apo lens matters, but in this application I need more light catering and more working distance - I have some Apo microscope objectives and high lumen LED torch, but they don't work well for field observation of natural behavior s of insects.
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Old Sunday 5th July 2015, 20:49   #25
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. Hi zzffnn,
I don't understand the stated apparent field of view regarding the zoom monocular.
Comparing the 6.521 Papilio II to the zoom monocular I get the following.

At 25 times the apparent field is roughly 55.
At 10 times the apparent field is roughly 35, maybe 33.

There is a big jump in apparent field of view as you go from 10 times to maybe 14 times.
Then there is a steady smaller increase in the field of view as you go from 14 times approximately to 25 times.

This is comparing one barrel of the 6.521 binocular to the zoom monocular without wearing glasses.
This is assuming that the 6.521 binocular has a 49 field as stated.

I used first my left eye with both instruments and then the right eye for both instruments.
I judged the fields of view by eyesight alone. There will be some small errors and my two eyes see slightly different fields of view, maybe because my dioptre correction is different for each eye.

I don't understand why you need a large apparent field of view to see detail centrally, but accept that this may be so for your eyes.

I get roughly the same results at 6 m, which are the figures above, and 70 cm computer screen to eye distance. The apparent fields of view may be slightly less for the zoom monocular compared to the Papilio binocular at the shorter distance.
But I don't know if the 49 stated for the Papilio would be the same at 6 m and 70 cm.

I focused both instruments initially at 6 m and then at 70 cm computer screen to eye distance.

I have not checked that the magnifications are correct for either instruments at the two distances. I don't know what the real figures are.

Last edited by Binastro : Sunday 5th July 2015 at 21:07.
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