My Travel Microscopes

[Apteronotus]

Like others I have been trying to figure out what would be a good microscope to take with me on vacation. Travels for me means traveling by car. I have not really thought about taking a microscope on a plane. We usually take trips in our car and with multiple people, luggage and other gear this means restricted storage space. I took a Zeiss Standard GFL with me last year, but that scope is heavy and I started to get worried about having the old Zeiss optics ride in a hot car over bumpy roads. The GFL's focus train is quite sensitive from what I read. In addition, the prisms in the binocular head could de-laminate. I am less worried about the objectives as I only took simple (but good) Zeiss achromats with me. I also like simplicity on the road; there are a lot of activities other than microscopy during the vacation and realistically there is little time to mess around with more sophisticated illumination or preparation techniques.
Before I go into the details, here is a picture of my two current travel microscopes, an Olympus HSB microscope with a horseshoe stand (left) sporting an Ihagee microscope to camera adapter and a Leica Stereozoom 4 stereo microscope (right).

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A while ago I found Rolf Vossen's website (https://microscopyofnature.com/) through the German Mikro-Forum (www.mikroskopie-forum.de). He has been mentioned in this forum as well. On his website Rolf describes the use of simple vintage student-grade microscopes, monocular horseshoe stands for microphotography with achromatic objectives and he gets good results. Moreover, he uses hybrid oculars, an amalgam of different combination of oculars to create projective oculars that can be used to project directly onto a camera sensor without having to use an additional camera lens. I thought I would give this a try as the horseshoe stands are mostly quite compact in size and have the advantage to have a completely upright orientation for the ocular tube which makes interfacing a camera easier. I don't mind just using the output of the camera for observation instead of a trinocular tube for simultaneous direct observation. In addition, there is no additional optics in between the objective and the ocular.
I obtained a finite-corrected 160mm Olympus HSB microscope inexpensively, a microscope with a 3-position turret and a simple lens in the microscope stage instead of a multilens substage condenser. Different apertures are achieved by means of a rotating disk with holes of different diameters that is build into the stage. I removed the lamp that the microscope came with and use a simple battery-powered LED video light (Ulanzi L2) that also has been mentioned on this forum. The light comes with an effective diffuser. Like Rolf I am using a vintage Ihagee camera to microscope adapter.
For a camera, I use an Olympus OMD-EM5 MII Micro Four Third (MFT) that is connected to the Ihagee adapter via a cheap Fotasy MFT to Exacta bayonett adapter. These cameras now can be acquired used relatively inexpensively. The camera can be tethered to a notebook computer via a USB cable or via wireless connection to an Ipad and utilizes Olympus own software for image and video acquisition. The camera has 16MPixels resolution and records HDTV-quality, but not 4K video.
I am using one of Rolf's hybrid oculars made from a Zeiss C5x ocular paired with a Leitz Periplan GF10x ocular (see Rolf's website for details). The objectives that I outfitted the microscope with are black Zeiss achromats (10x, 25x, and 40x mounted to the microscope and a 2.5x Zeiss silver plan objective, mounted when needed).

HSB.jpg (132.49 KiB) Viewed 5837 times

This picture is an action shot in the "field" with the Olympus in the foreground with camera mounted and video light underneath.


The companion to the compound microscope is a Leica Stereozoom4 stereo microscope that I also obtained relatively cheaply, and looked like it had never been used. I outfitted the head with a B&L stand and a 2x B&L barlow lens. From what I learned on this forum, B&L made the Stereozoom4 before they got rolled into Leica. I find that they make excellent field stereo microscopes due to their compact size and nice optics. With 10x oculars and its 0.7-3x zoom objective and the 2x barlow the scope can go up to a 60x magnification and is a great complement to the Olympus HSB. I use a 1.25" telescope adapter (SVBony) to mount the camera to the eyepiece of the scope, in this case afocally also using a 28mm manual MFT camera lens made by Meike. I also use the video light under or above the stage to illuminate specimen.

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Here is a picture of the Leica Stereozoom 4 with the video light underneath of the stage and the camera mounted to one of the eyepieces.


Here are a couple images obtained with the Olympus in this configuration. If I remember correctly, the Bosmina was photographed with the 25x objective, the freshwater algae with the 40x objective.

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Spirogyra.jpg (98.66 KiB) Viewed 5837 times

Here is a link to a video with the Bosmina waterflea from the picture above




and here are a couple of videos of marine mollusks obtained with the stereomicroscope. The magnification was between 40-60x. I believe the organisms were not larger than around 1 mm.





In summary, I think the quality is decent for relatively inexpensive, compact and robust microscopes, at least for my purposes.

[einman]

Very Nice! As you mentioned if they serve "your" purpose than that is all you need! One of my favorite stereoscopes is a B&L Stereozoom 7. It has incredibly good optics with an na of 0.1, equal to superior to more modern scopes. What is important is that you are enjoying the hobby!

[Sure Squintsalot]

I like the logic behind having a simple body, but with decent optics and forgoing the direct viewing altogether. The results look pretty good too, though I'd like to have dark field for a travel/field scope. Have you tried placing DF stops on your light source?

...and what, by the way, do you figure the complete microscope weighs, icluding its box?

[Scoper]

Excellent post..very informative!

[zzffnn]

Great post, thank you, Apteronotus.

How heavy is the Olympus HSB microscope without camera, please?

Also, it seems that Rolf’s DIY projection eyepiece need to be custom matched to specific objectives by trial-and-error? That seems to be inconvenient for some users. And not many people are great at eyeballing optical distortions in such trial-and-error.

I read Rolf Vossen's web page on DIY’ing such projection eyepiece. I could be wrong, though I get the feeling that there may be a few general formula for such DIY, but Rolf did not really summarize them.

For true portable travel use, I would think that a smartphone (which I always carry in my pocket) adapted afocally over 10x eyepiece would be quite a bit lighter than any camera (yes, I do have a micro four thirds Olympus camera too, but I mostly use it at home). When good amount of illumination is provided for portable travel use, a smart phone can produce very good results too, to a level almost as good as a real camera.

I bought a “ 3-Axis High-Precision Telescope Phone Adapter - ACCUVIEW Digiscoping ” from eBay and like it quite a bit for its light weight and adjustability.

[blekenbleu]

Also, it seems that Rolf’s DIY projection eyepiece need to be custom matched to specific objectives by trial-and-error? That seems to be inconvenient for some users. And not many people are great at eyeballing optical distortions in such trial-and-error.

Yes, using instead Nikon CF or CFN objectives would enable direct projection (no relay lens) to a mirrorless camera sensor about 150mm above objectives, for a smaller and lighter package.

[apochronaut]

I like that you break this popular topic down a bit and use the term, "travel microscope", differentiating it from pocket microscope, portable microscope or a field microscope. Pocket microscopes due to their diminutive size , lack certain features, whereas a portable or travel microscope can be expected to achieve relatively full featured results. Both of those terms have also been used to describe a field microscope. Your options yield good results, yet are a bit heavy : too heavy to be true field microscopes, yet small enough to go in luggage. More along the lines of Army Field Microscopes, which could in fact be back packed but were limited to medical uses, not more general biological applications.
In the past, the term travelling microscope was used as a term for a scope that was small enough to be taken with you. No means of conveyance was implied usually, and different manufacturers made various claims of performance and sizes varied considerably. This was somewhat brought into focus by the McArthur field microscope, which became the preeminent of field microscopes, offering laboratory performance in a small package, almost a pocket package. It is safe to say that all others are judged in their equivalence to the McArthur, in it's most complete form.
I would like to see more concrete terms applied to such instruments with somewhat defined performance characteristics and portability classes. Here is a start, to be refined by anyone.
Pocket : Can be carried on the person. Max. 300 gm.
Portable Field : Can be carried in a bag or kit on the person. Max. 1000 gm.
Portable Lab : Can be carried in a case or backpack. Max. 4000 gm.
Travelling : Requires a means of conveyance. Max. 6000 gm.
I don't know what to do with performance characteristics. Obviously, the physical dimensions will impose natural limitations on performance to a large degree.

[Apteronotus]

I appreciate all the great comments. Discussions like this are what attracted me to the forum in the first place. I got a little busy at work in the last couple of days, but will take the time tomorrow to write back in more detail.

[Apteronotus]

Very Nice! As you mentioned if they serve "your" purpose than that is all you need! One of my favorite stereoscopes is a B&L Stereozoom 7. It has incredibly good optics with an na of 0.1, equal to superior to more modern scopes. What is important is that you are enjoying the hobby!

Thank you, Einman! I have one as well and like it very much, too. Although I would be more worried about taking it on the road than the SZ4. It is larger and from what I read has a more complicated mechanism, so maybe more sensitive to vibrations and perhaps harder to repair?

And I definitely enjoy microscopy as a hobby. I have used microscopes professionally in the past, but for a while with a much more narrow focus (mammalian cell cultures). For me it is almost spiritual to go back and re-discover the incredible diversity of life.

[Apteronotus]

I like the logic behind having a simple body, but with decent optics and forgoing the direct viewing altogether. The results look pretty good too, though I'd like to have dark field for a travel/field scope. Have you tried placing DF stops on your light source?

...and what, by the way, do you figure the complete microscope weighs, icluding its box?

I like dark field, too. In a travel scope for me it would be sufficient to have dark field at lower magnifications. I have not tried it yet, but Rolf Vossen says on his website that he was able to make darkfield stops for it, up to 20/25x I believe. The rotating disk with the apertures in it kind of lends itself to outfitting one with a darkfield stop. The Olympus HSB microscope outfitted with optics and Ihagee adapter weighs 6.8 pounds by itself (I don't have a dedicated box for it yet) compared to abut 15 pounds for the Zeiss GFL. For its size, the Olympus still has a good heft, but is much more compact in its size.

[Apteronotus]

Excellent post..very informative!

Thank you, Scoper! My hope is that at least if will serve as another data point for someone in what feels like an infinite 'soup' of possible configurations. And it is fun to exchange observations and ideas with this great crowd.

[Apteronotus]

Great post, thank you, Apteronotus.

How heavy is the Olympus HSB microscope without camera, please?

Also, it seems that Rolf’s DIY projection eyepiece need to be custom matched to specific objectives by trial-and-error? That seems to be inconvenient for some users. And not many people are great at eyeballing optical distortions in such trial-and-error.

I read Rolf Vossen's web page on DIY’ing such projection eyepiece. I could be wrong, though I get the feeling that there may be a few general formula for such DIY, but Rolf did not really summarize them.

For true portable travel use, I would think that a smartphone (which I always carry in my pocket) adapted afocally over 10x eyepiece would be quite a bit lighter than any camera (yes, I do have a micro four thirds Olympus camera too, but I mostly use it at home). When good amount of illumination is provided for portable travel use, a smart phone can produce very good results too, to a level almost as good as a real camera.

I bought a “ 3-Axis High-Precision Telescope Phone Adapter - ACCUVIEW Digiscoping ” from eBay and like it quite a bit for its light weight and adjustability.

Thank you, zzffnn! The scope without camera is 6.8 pounds.
Rolf describes a number of different combinations of oculars for finite objectives of different brands (Leitz, Olympus, Zeiss). He finds a pretty good number of combinations that work reasonably to excellent for the corrections characteristic for each brand and also tested out what combination to use for e.g. a MFT camera versus an APC-type camera. I just followed his advice for making a hybrid ocular for Zeiss finite scopes outfitted with a MFT camera. He says that the best combination that he found was made from a Zeiss C5x and a Leitz Periplan GF 10x. I looked at the pictures of the oculars in his article, matched them to oculars on Ebay and ordered them. I did this twice for different Zeiss microscopes. I have used the hybrid oculars with Zeiss achromats and plan objectives (have not tried them with my Neofluars yet, although Rolf tested that out, too I believe). To my eyes the resulting image looks good, at least as good as an afocal configuration. Although I have not done a careful comparison myself, Rolf has tested this out pretty extensively. He also describes another method of turning a regular eyepiece into a projective by extending the barrel with a ring of certain length. Some people on the German forum also comment favorably on his method and I believe Microbob has done so in this forum as well. Therefore, I believe there is a reasonable chance of success that his recipes would work. However, I would advice to look at the pictures carefully to match the ones from his recipes with potential Ebay candidates before going on a shopping spree. I think it is a reasonable way of getting a projective if one is not available or too expensive. It avoids potential problems with reflections from additional camera lenses and keeps the size of the microscope with attached camera reasonable.
I have to admit so far I am not very versed in taking micrographs with my cellphone that I am happy with despite using dedicated smartphone adapters. Maybe I should give the adapter that you mention a try? I agree that this would make for an even smaller combination. I always travel with my MFT camera anyway with a small selection of camera lenses like macro lenses etc, so for me taking the camera is not adding to the bulk.

[Apteronotus]

Also, it seems that Rolf’s DIY projection eyepiece need to be custom matched to specific objectives by trial-and-error? That seems to be inconvenient for some users. And not many people are great at eyeballing optical distortions in such trial-and-error.

Yes, using instead Nikon CF or CFN objectives would enable direct projection (no relay lens) to a mirrorless camera sensor about 150mm above objectives, for a smaller and lighter package.

I agree. I have Nikon objectives that I am using on another scope in direct projection. I would expect that combination to also give excellent results. It would eliminate the need for the projective. I am using the described combination with the Zeiss objectives as this is what I had for use on this scope.

[zzffnn]

Joe, does your smartphone- microscope adapter have Z axis adjustment to change distance between microscope visual eyepiece and smartphone lens? That feature is important for optimal sensor coverage. If you using a two-camera iPhone 13, use its main camera (the lower right one).

I like the eBay smartphone adapter, after trying it on my microscope. I have no association with the seller, though here is the listing that I bought:
https://www.ebay.com/itm/126001042384

The smartphone adapter weights 8.2 oz (233 grams) by itself (without phone or eyepiece) and came with a Bluetooth remote control for phone camera that works with my iPhone 13. A wide field eyepiece can almost cover the horizontal (the shorter) dimension of the phone screen, with the Z axis adjustment of this adapter, though as with all phone adapters (intended for wide angle smartphone lenses), you see a circular image, not a rectangle like what you get from real camera adapters.

And just another data point for other microscopists looking for travel options: my LOMO Biolam 112 model, when loaded with a binocular head + two eyepieces + 4 objectives + NA 1.25 (DIY darkfield capable) Abbe condenser + phone adapter, weights 8 lb 1.7 oz (3677 grams). Its monocular (angled tube) version weights 6 lb 12.5 oz (3076 grams), with one eyepiece + 4 objectives + NA 1.25 (DIY darkfield capable) condenser + phone adapter. Those weight values do not include a case, a slide holder, microscope light source or a camera / a phone.

[zzffnn]

Joe, I would like to try Rolf’s DIY projection eyepiece myself.

I don’t think lens internal reflection is an issue with the vintage Nikon manual lens that I used with my MFT camera, though it is a bit heavy. A DIY projection eyepiece + focusing helicoid adapters / tubes should be lighter and optically simpler though.

When you said: “ (Rolf) says that the best combination that he found was made from a Zeiss C5x and a Leitz Periplan GF 10x”.

That “best combination” is best for your specific set of Zeiss 45mm parfocal achromats, or is it good for many different achromat objectives of different brands (such as Leitz)?

I read that Rolf has tried different DIY projection eyepieces with different 45 mm and 37 mm parfocal objectives of different brands. He did not seem to publish test results with older 32-34 mm parfocal short objectives (old LOMO, Zeiss, Nikon or American Optical Spencer). I saw some optical distortions (CAs) in his test photos, though they seem to look good generally.

[Apteronotus]

I like that you break this popular topic down a bit and use the term, "travel microscope", differentiating it from pocket microscope, portable microscope or a field microscope. Pocket microscopes due to their diminutive size , lack certain features, whereas a portable or travel microscope can be expected to achieve relatively full featured results. Both of those terms have also been used to describe a field microscope. Your options yield good results, yet are a bit heavy : too heavy to be true field microscopes, yet small enough to go in luggage. More along the lines of Army Field Microscopes, which could in fact be back packed but were limited to medical uses, not more general biological applications.
In the past, the term travelling microscope was used as a term for a scope that was small enough to be taken with you. No means of conveyance was implied usually, and different manufacturers made various claims of performance and sizes varied considerably. This was somewhat brought into focus by the McArthur field microscope, which became the preeminent of field microscopes, offering laboratory performance in a small package, almost a pocket package. It is safe to say that all others are judged in their equivalence to the McArthur, in it's most complete form.
I would like to see more concrete terms applied to such instruments with somewhat defined performance characteristics and portability classes. Here is a start, to be refined by anyone.
Pocket : Can be carried on the person. Max. 300 gm.
Portable Field : Can be carried in a bag or kit on the person. Max. 1000 gm.
Portable Lab : Can be carried in a case or backpack. Max. 4000 gm.
Travelling : Requires a means of conveyance. Max. 6000 gm.
I don't know what to do with performance characteristics. Obviously, the physical dimensions will impose natural limitations on performance to a large degree.

Thank you, Apochronaut for these interesting thoughts! I believe that makes sense to classify the instruments by weight and what can be carried into the field. Or by what capabilities one requires for what which application e.g. a microscope used for medical field applications such as blood work to look for malaria parasites or sickle cell anemia probably should be capable of phase contrast, maybe in some cases even DIC (is that how the field diagnosis was done? Probably done by PCR or Elisa test now). That would be like a full lab microscope, maybe a more compact version of one and probably would not be transported in a backpack. I have to admit I am somewhat ignorant of the applications of the intermittent weight class like portable field or portable lab microscopes. I understand truly pocket-able microscopes' use for a quick analysis at a collection site of for example a plankton/diatom sample to decide if harvesting is worthwhile at the site. Or for a quick species determination of for example a mushroom. Although I have done extensive field work in freshwater ecology as an undergraduate student, we usually collected samples and then took them to a lab or a cabin to be analyzed in the evening. However, one has to fix and preserve the samples to get an idea about the species distribution. Life plankton samples will change during transport due to crustaceans filtering out most of the algae unless the organisms in the plankton sample are separated by filtration through different mesh sizes. To get a glimpse of what perhaps the interactions in the true community look like I guess in this case it would make sense to analyze the samples right away? I am not sure what the applications of a microscope transportable in a backpack would be. It would be interesting to hear from people for what applications they use these intermittent classes truly out in the field, how they chose their microscope and what compromises they were willing to live with. I hope my rambling makes sense.

[Apteronotus]

Joe, does your smartphone- microscope adapter have Z axis adjustment to change distance between microscope visual eyepiece and smartphone lens? That feature is important for optimal sensor coverage. If you using a two-camera iPhone 13, use its main camera (the lower right one).

I like the eBay smartphone adapter, after trying it on my microscope. I have no association with the seller, though here is the listing that I bought:
https://www.ebay.com/itm/126001042384

The smartphone adapter weights 8.2 oz (233 grams) by itself (without phone or eyepiece) and came with a Bluetooth remote control for phone camera that works with my iPhone 13. A wide field eyepiece can almost cover the horizontal (the shorter) dimension of the phone screen, with the Z axis adjustment of this adapter, though as with all phone adapters (intended for wide angle smartphone lenses), you see a circular image, not a rectangle like what you get from real camera adapters.

And just another data point for other microscopists looking for travel options: my LOMO Biolam 112 model, when loaded with a binocular head + two eyepieces + 4 objectives + NA 1.25 (DIY darkfield capable) Abbe condenser + phone adapter, weights 8 lb 1.7 oz (3677 grams). Its monocular (angled tube) version weights 6 lb 12.5 oz (3076 grams), with one eyepiece + 4 objectives + NA 1.25 (DIY darkfield capable) condenser + phone adapter. Those weight values do not include a case, a slide holder, microscope light source or a camera / a phone.

Hi zzffnn, no, my phone adapter does not have a z axis adustment other than just moving the clamp along the eyepiece tube to a different height. But I found that one runs out of tube quickly which makes the whole thing somewhat unstable. I thought about DIY-ing a tube extension of sorts to give the clamp a little extra length to clamp onto.

[Apteronotus]

Joe, I would like to try Rolf’s DIY projection eyepiece myself.

I don’t think lens internal reflection is an issue with the vintage Nikon manual lens that I used with my MFT camera, though it is a bit heavy. A DIY projection eyepiece + focusing helicoid adapters / tubes should be lighter and optically simpler though.

When you said: “ (Rolf) says that the best combination that he found was made from a Zeiss C5x and a Leitz Periplan GF 10x”.

That “best combination” is best for your specific set of Zeiss 45mm parfocal achromats, or is it good for many different achromat objectives of different brands (such as Leitz)?

I read that Rolf has tried different DIY projection eyepieces with different 45 mm and 37 mm parfocal objectives of different brands. He did not seem to publish test results with older 32-34 mm parfocal short objectives (old LOMO, Zeiss, Nikon or American Optical Spencer). I saw some optical distortions (CAs) in his test photos, though they seem to look good generally.

The hybrid eyepiece I tried is this one:
Hybrid eyepiece C5-PeriGF10: field lens Zeiss C5x - barrel Zeiss C5x - eye lens Leitz Periplan GF10x: "This hybrid eyepiece has proven to be the best combination so far for Zeiss 160mm objectives in combination with micro 4/3 en (sp) APS-C cameras" (see: https://microscopyofnature.com/micropho ... -eyepieces). He also gets good results with a different method, a simple extension of the eyepiece barrel with for example 3D printed tubes (see: https://microscopyofnature.com/using-ex ... hotography).

I believe he points out distortions where they occurred, he definitely looks out for them to a certain extent. He looks at the images from the point of view of what would be generally pleasing to a hobbyist, maybe not so much to a professional microscopist that needs to get the last bit of performance out of an image? Although if I remember correctly he is a professional microscopist himself, but I don't want to speculate too much as I don't know him personally.

[woyjwjl]

Pocket : Can be carried on the person. Max. 300 gm.
Portable Field : Can be carried in a bag or kit on the person. Max. 1000 gm.
Portable Lab : Can be carried in a case or backpack. Max. 4000 gm.
Travelling : Requires a means of conveyance. Max. 6000 gm.

Well, your classification is very reasonable.

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What I am curious about is that my sales on eBay are not good, is it due to the price?
Okay, if the microscopists on the forum can make the most of it, please contact me through PM, the price is not a problem.

[autumnwalk2]

I once carried a laboratory microscope weighing more than 20 kg in a pickup truck with a portable generator to observe it right by the sea. It was a trip over 1000 km. It didn't produce much results. Because I was busy with other things, so I couldn't observe much. Thinking about my experience at that time, it was too heavy and I was so worried that the microscope might break down due to vibration. So now, I am preparing to travel with a lighter microscope with a generator. Even if it is light, it will weigh more than 10 kg. I want to travel along rivers across the country with that microscope.

[Hobbyst46]

...I have used the hybrid oculars with Zeiss achromats and plan objectives (have not tried them with my Neofluars yet, although Rolf tested that out, too I believe). To my eyes the resulting image looks good, at least as good as an afocal configuration...

IMO, based on tests with an APS-C camera and a stage micrometer (without coverslip), the 10X-8X-10X (full hybrid) KPL eyepiece with 45mm parfocal Zeiss planachromats (25X0.45) and neofluars (10X0.30, 16X0.40, 40X0.75), work very well, indeed better and more convenient than afocal through an ordinary KPL eyepiece. The only significant aberration is very slight pincushion that can be ignored. Thanks to Rolf Vossen.