Binoculars as microscope - Penta Papilio 6.5x21 vs Minox BF 10x42 (1 Viewer)

[brocknroller]

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

 

[Binastro]

. 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.

 

[ceasar]

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

 

[zzffnn]

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.

 

[Binastro]

. Hi zzffnn,
I don't understand the stated apparent field of view regarding the zoom monocular.
Comparing the 6.5×21 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 6.5×21 binocular to the zoom monocular without wearing glasses.
This is assuming that the 6.5×21 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.

 

[zzffnn]

Dear Binastro,

You are right! Both Orion's product page and I got it wrong (Orion listed 3.3-2.4 as both real FOV and AFOV and I calculated it wrong).

AFOV of 25x should be (2.4 degrees) x (25 fold magnification) = 60 degrees, which is pretty close to your 55 degrees estimation.

AFOV at 10x is 3.3x10=33 degrees, so you are exactly right!

Thank you so much for mentioning that 14x of the zoom has much larger AFOV than 10x. 14x and up is mostly what I would be using, so that is very encouraging!

I need large AFOV as my eyes are weird
I guess primarily because I usually have glasses on (due to terrible eye sight and significantly worse left eye), so my eyes do not get close enough to get the full calculated view field (when I remove my glasses, view field increase significantly).

As an example to illustrate what my strange eyes demand - in my pursue of microscopy, I spent lots of money on wide field high eye point eyepieces :-( (while most people can live with eye lens the size of a bean and use the savings on Apo objectives).

 

[typo]

Somewhat off at a tangent but I see Carson has magnifiers, monoculars and adaptors to work with the Samasumg Galaxy S4 and iPhone which look fun. Have a look at the videos.
http://www.carson.com/accessories/smart-phone-adapters/1386-ml-415
https://youtu.be/MfrEJn8e57g

David

 

[jaymoynihan]

... binoculars for 'bugging.' ... 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.

Not with the Papilio, nor with with the Vortex Viper 8x32 HD, which has a very nice close focus.

I use for looking at insects is a microscope pen.

Must not be an eyeglass wearer

 

[jaymoynihan]

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

Have had one for a few years, love it. But i seldom use it in macro mode due the necessity of adding/subtracting macro lenses...
However, it lives in my briefcase of shoulder bag. Many uses.

 

[Gijs van Ginkel]

zzffnn,
A number of brands have made binoculars/monoculars which can function as a microscope with low magnification. The Leica 8x20 has already been mentioned, but Pentax has made an 8x30 monocular with close-up lens making magnifications of 25x possible. Zeisss has made a special piece of equipment which in combination with the small 6x20, 8x20 and 10x25 pocket binoculars makes a binocular microscope with low magnification. There is also a number of Japanese brands which just like the monocular Pentax 8x30 can function as a low magnification microscope. Zeiss Jena has made a special piece of equipment (now rarely found) which in combination with one of their monoculars functions a s a low magnification microscope. The Zeiss 6x20 monocular can focus up to a very short distance which gives a 6x magnifying instrument which allows the close observation of insects etc,.
Undoubtedly there are more possibilities, but this is what popped up in my mind.
Gijs van Ginkel

 

[brocknroller]

. 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.

Yes, the working distance of the magnifying pens is short. Sometimes the shadow of the pen darkens the insect you want to view. That's why I recommended the pens with the built-in lights. It really is like a portable microscope. The Papilio is much more versatile as a macroscope.

Brock

 

[zzffnn]

Gents, I got an used Orion 10-25x42 from Amazon warehouse deals for $66 shipped. Condition is like new and everything works well. For the price, I am happy with it.

Binastro described it well.

To my eyes, quality view is between 10 to 18x. Beyond 20x or so, image gets dark very quickly and focus depth is very shallow (as expected). Decent with my glasses and much better without (at >= 20x there is reflection between my glasses and the monocular). I tend to leave it at 18x and use it on tripod.

I would say my Pentax Papilio 6.5x and old Russian 10x42 produce sharper images. But for my casual use, the Orion is just fine. And I like it as a portable 18x macroscope as it is. After all, there is no better alternative on the market, if you want a 18x portable macroscope.

I also found that my old Russian 10x42 porro biniculars can work as a maroscope with +2 diopter (camera) lenses in front of the objectives. I simply use mounting putty to attach the diopter lenses (which are Vivitar series 1 62 mm). +4 diopters are too difficult to use due to shallow focus. With +2 diopter they can focus at around 0.3 meter away. Between Orion at 10x vs. this DIY, I like the DIY better as its image is shaper, brighter and more comfortable (bino vs mono). But the DIY rig is quite heavy and only 10x.

 

[zzffnn]

Gijs van Ginkel,

Do you know the name/model number of the Zeiss products that you mentioned? Thank you.

 

[zzffnn]

It looks like I spoke too soon. My field test showed that to observe live insect behavior, a macroscope has to focus quickly and follow the focus very well (insects move very fast). With that criterion in mind, my results are:

1) Pentax Papilio 6.5x 21 works very well (focus whel is very fast and smooth), I only wish for more magnification. Looks like I have to buy the 8.5x version later on. Jay, since you study ants with your Papilio 8.5X, I assume that you like it that way?

2) Orion 10-25x42 does not work well. It took too long to focus at its close focus point (2 feet away) and its focus wheel cannot turn fast enough to follow an insect.

3) my DIY +2 diopter plus Russian 10x42 porro binoculars does not work at all. Its focus wheel does not work at close focus and I have to move the entire binoculars.

With that said, I would probably still keep the Orion. Its 25x magnification is useful sometimes and it can be adapted to my micro 4/3 camera very well using an Orion digiscoping adapter (Orion SteadyPix Pro). I will use it for photographing faraway subjects.

 

[Binastro]

Hi zzffnn,
The Minolta compact AF 8 8×23 autofocus binocular focuses to 2 m according to the specifications.
It achieves critical focus in about one 10th of a second.
I don't know if it could be adapted for closer focus. The autofocus module might not work with a close-up lens, and am not sure how compatibile it is with similar dioptre close-up lenses on the objectives.
In addition, the objectives do not move sideways.
It was also available as a 10×23 with similar specifications.

Looking through the viewfinder of a compact camera, it may be possible to follow an insect in real-time with continuous autofocus.

The Minolta autofocus binocular is really quite amazing, and I don't know why it was not developed further to reduce the size. There are other, possibly earlier Minolta autofocus binoculars, that may not be so good, and the 8x23 may have been their last attempt. Obviously it didn't sell very well.

 

[Binastro]

I've just been using the Minolta 8×23, and the autofocus does work at 2 m. Even in rather poor light.
I get a better view if I slightly change the IPD when using it close-up.

P. S.
I've just been looking through the electronic viewfinder of my camera, and when I point the television remote control at the lens, I can clearly see the infrared quite largish apparently white circular beam repeatedly going on and off when I press the remote control button.

However, when I point the Minolta 8×23 binocular at the camera lens and then press the autofocus button, I see nothing. I also tried photographing the binocular with another camera while pointing the binocular at the lens and again nothing.
So I don't know how the autofocus mechanism works on this Minolta binocular.

 

[Binastro]

. Hi zzffnn,
I'm sorry that the monocular proved to be unsuitable, but I think the exercise was worth doing.

Some of the other monoculars, from Opticron and others, which are specially made for close focus, might work well with moving insects.

As to the Minolta autofocus binocular, I think that the autofocus may be passive and work perhaps on contrast.
It might actually work just by putting two equal close-up lenses in front of the objectives. I'm not sure that I have a matched pair to try it.
I am impressed by the Minolta autofocus binocular's ability. It is probably more than 20 years old.

Some modern cameras will I think work very well in continuous autofocus even close-up.

 

[zzffnn]

Thank you Binastro for your kind comments. No worries. I like the Orion enough to keep it.

The Minolta that you mentioned close focuses at 2 meters, which is too far for my use (observing live insect behavior).

On the other hand, those microscope convertible type monoculars, such as Opticron, focus too close (most at less than 0.1 m) for me. Insects would be disturbed when I approach that close. And when I really need to get that close for maximum resolution, I would catch the insect and put it under a real microscope (whose focus distance is less than 0.12 m and mostly less than 0.05 m).

Sorry, my eyes don't like observing long term using camera's viewfinder. Battery drains quickly that way and my neck/back also hurts (remember I would be close to ground when observing insects).

 

[Binastro]

. Hi zzffnn,
I am now trying the 6.5×21 Papilio II with an Opticron UTA universal tele-adapter, 2.5 times push fit.
This is the version which is a companion to the 8×42 and 10×42 monocular. It says for DBA and BGA monoculars.
I think, though, there may be many different adapters available to fit these to different binoculars? These may be free if you buy the Opticron adapter new.

There is excessive eye relief for me, although there is a long travel rotating eyecup that more or less suits me.
I'm using this on the right side of the Papilio binocular. One has to centre the adapter to get the full field of view. I think that it would be easy to use this wearing spectacles.

The apparent field of view using the adapter is about 42°.
The magnification is around 16 times, I think, which gives a 16×21 monocular. The real field of view is probably about 2.5°

It is possible to get the full use of the focus wheel with the left hand, and I think that this arrangement would suit the viewing of insects.
However, although the resolution is better than without the adapter, hand tremor may mean that there is not that much gained in actual fact.
It is something that you might consider trying if you have access to this tele-adapter.

I think that a two times booster would be better. There are some but they are expensive.
The Opticron adapter cost £49 as new, second hand.

 

[Binastro]

Re. post 39.

The image using the 2.5 times tele-adapter is a lot duller than the view through the Papilio binocular without the adapter.
However, on a sunny day the image may well be bright enough when viewing insects.

I was using the combination of the 6.5×21 Papilio II and the 2.5 times tele-adapter at a distance of about 0.5 m computer screen to the objectives of the Papilio II.
Of course the combination is longer than the binocular alone.
The specifications say that the adapter has a height of 76 mm, a diameter of 46 mm and a weight of 110 g.