My new Olympus BHS BH2

What equipment do you use? Post pictures and descriptions of your microscope(s) here!
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mintakax
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My new Olympus BHS BH2

#1 Post by mintakax » Wed Aug 07, 2019 11:05 pm

Its been a fun few days setting up this new (to me) microscope. It is an Olympus BHS BH2 with Phase and DIC. I don't have any Phase objectives (yet) so I haven't had a chance to try that part. I have been playing with the DIC quite a bit.

If there is anyone reading this that has an Olympus BHS DIC setup I would really appreciate asking a couple of questions. I've read and followed of Alan Wood's articles on the BHS, including the DIC setup but there is one step where my result is a bit dodgy.

The scope came with a Diagnostic Instruments photo tube and an NFK 2.5x photo eyepiece. I have my Nikon Z6 full frame mirrorless connected fine, but I would like the image projected on the camera's sensor to be less magnification. I'm thinking of buying ($$$) a 1.67x photo eyepiece but they are so darn expensive. Any comments of how that would perform ? The small screen on the left is an external recorder.

I have setup a small aquarium with plants and algae from a local pond. I want to minimize the harm (if possible) to any of the creatures so I only use concave slides which I've found makes it tougher due to swimming in and out of focus, but I'm getting by. I've a lot of experience taking underwater, drone and wildlife videos but this is my first attempt at microscope videography and I'm just learning the ropes. Also I haven't quite got the hang of DIC yet but find it fascinating. Here is a video composite of some of my pond creatures, I think most were taken using DIC.

https://vimeo.com/352578557

I'm having a blast :D
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PeteM
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Re: My new Olympus BHS BH2

#2 Post by PeteM » Thu Aug 08, 2019 12:01 am

Looks like a great setup. Can't see in the picture -- I assume you have the BH2 DIC condenser as well? Are those SPlans on the scope?

As for the 1.67x - might try imaging with less powerful objectives to capture the on-screen magnification you want?? If there isn't a 20x Splan on the turret, that might be a good addition, and likely much cheaper than the 1.67x.

geo_man
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Re: My new Olympus BHS BH2

#3 Post by geo_man » Thu Aug 08, 2019 12:12 am

wow, beautiful and professional video! congrats!! can you say a few words about your aquarium setup?

mintakax
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Re: My new Olympus BHS BH2

#4 Post by mintakax » Thu Aug 08, 2019 3:43 am

PeteM wrote:Looks like a great setup. Can't see in the picture -- I assume you have the BH2 DIC condenser as well? Are those SPlans on the scope?

As for the 1.67x - might try imaging with less powerful objectives to capture the on-screen magnification you want?? If there isn't a 20x Splan on the turret, that might be a good addition, and likely much cheaper than the 1.67x.
Thanks ! Yes, it is a BH2 DIC condenser. The reason I'm thinking 1.67x is so I can better match the camera FOV with what I see when I look through the eyepieces, I think it would make for easier hunting and recording. What do you think ?

Another question... Is it typical with trinoculars that the eyepiece and camera are not quite parfocal ? Mine is off slightly, and if I could drop the photo eyepiece farther down into the photo tube the two images would be parfocal. Maybe there is a trick that I'm missing ?

These are the objectives that came with the setup:
DIC and Phase 1.4NA condenser. Dic (10,20,40,100) and phase inserts (10,40,100) included
Splan APO 10 & 20x
Splan 40x
Nikon Plan 100x

mintakax
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Re: My new Olympus BHS BH2

#5 Post by mintakax » Thu Aug 08, 2019 3:47 am

geo_man wrote:wow, beautiful and professional video! congrats!! can you say a few words about your aquarium setup?
Oh thank you ! Its a ten gallon glass tank, in my garage, with a small air pump and bubbler stone. I have about 5gal of pond water in it. Occasionally I get more samples and put them in. I really don't know what I'm doing, but it seems to be working so far !

I just cant get over how cool and "alien" these pond creatures are.

mintakax
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Re: My new Olympus BHS BH2

#6 Post by mintakax » Thu Aug 08, 2019 3:53 am

I forgot to mention that I purchased a second lamp housing and the necessary components to fit fiber optic lighting thanks to MichaelG's suggestion. I'm looking forward to seeing what effect the cooler lighting produces.

http://www.microscopy-uk.org.uk/mag/ind ... fibre.html

Tom Jones
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Re: My new Olympus BHS BH2

#7 Post by Tom Jones » Thu Aug 08, 2019 4:48 am

First, I'd suggest you peruse this site: http://www.krebsmicro.com/ Charlie Krebs is the BHS-DIC Photomicrography Guru. Pretty much all of your questions are answered there.

The projection eyepieces are designed to stay away from the outer edges of the field where image quality can be a bit less. The 2.5x is designed for full frame, and if you have the DI PA1-10A adapter, that's the correct one. The 1.67x does about the same, but the projected area is appropriate for an APS-C sensor. That's way too small for the full frame sensor in my opinion, although the SPlans are wide field so it may work out better than I imagine.

As PeteM suggested, a lower magnification objective would shrink the field a lot cheaper than the 1.67x. What he didn't mention is the addition of a BH-2 CA magnification changer such as this one:

https://www.ebay.com/itm/Olympus-BH-Ser ... Sw-1Zcgq5H

It also has the benefit of having a built-in Bertrand lens to help center your phase rings. You won't need a phase telescope.

I don't remember if there are vignetting problems using the mag changer along with the DIC intermediate tube. It's been awhile since I used mine that way. Mag changers are really nice to help with framing. I have a couple I use with my BHS-DIC system and BH-2 outreach scopes, and BX versions (U-CA) for my BX-50s.

I second the suggestion for an SPlan 20x if you don't already have one. They're very handy with pond life.

There are other ways to do it as well, but they will take some detective work on your part. No manufacturer I know of has a real 35mm full-frame sensor for video. Even Red uses Super 35. Matching field size to sensor size got a lot more difficult when the different aspect ratios and resolutions became available on the same sensor. Because of that, you are not using all of the sensor anyway, and the size varies, a lot, depending on the video resolution and aspect ratio you use. Each resolution/aspect ratio will have a different optimum projection set.

From Nikon for the Z6:
FX (36x24) image area: 6048 x 4024 (L: 24.3 million), 4528 x 3016 (M: 13.7 million), 3024 x 2016 (S: 6.1 million)
DX (24x16) image area: 3936 x 2624 (L: 10.3 million), 2944 x 1968 (M: 5.8 million), 1968 x 1312 (S: 2.6 million)
1:1 (24x24) image area: 4016 x 4016 (L: 16.1 million), 3008 x 3008 (M: 9.0 million), 2000 x 2000 (S: 4.0 million)
16:9 (36x20) image area: 6048 x 3400 (L: 20.6 million), 4528 x 2544 (M: 11.5 million), 3024 x 1696 (S: 5.1 million)

As an example, on my BHS I use a Panasonic GH4 camera and shoot 4K UHD. To get the best image I use a NFL 3.3x projection lens (to get any necessary eyepiece color correction) and a U-PMTVC 0.3x C-mount adapter to give me essentially direct projection (3.3 x 0.3 =0.99x), and fits very well. If I shoot instead 4K DCI, it doesn't fit as well.

Time to do a little research to figure out the best way to get what you need for what you are going to shoot.

Tom

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Re: My new Olympus BHS BH2

#8 Post by 75RR » Thu Aug 08, 2019 4:58 am

Congratulations on your BH2 and your video!
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PeteM
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Re: My new Olympus BHS BH2

#9 Post by PeteM » Thu Aug 08, 2019 5:01 am

mintakax wrote:
PeteM wrote:Looks like a great setup. Can't see in the picture -- I assume you have the BH2 DIC condenser as well? Are those SPlans on the scope?

As for the 1.67x - might try imaging with less powerful objectives to capture the on-screen magnification you want?? If there isn't a 20x Splan on the turret, that might be a good addition, and likely much cheaper than the 1.67x.
Thanks ! Yes, it is a BH2 DIC condenser. The reason I'm thinking 1.67x is so I can better match the camera FOV with what I see when I look through the eyepieces, I think it would make for easier hunting and recording. What do you think ?

Another question... Is it typical with trinoculars that the eyepiece and camera are not quite parfocal ? Mine is off slightly, and if I could drop the photo eyepiece farther down into the photo tube the two images would be parfocal. Maybe there is a trick that I'm missing ?

These are the objectives that came with the setup:
DIC and Phase 1.4NA condenser. Dic (10,20,40,100) and phase inserts (10,40,100) included
Splan APO 10 & 20x
Splan 40x
Nikon Plan 100x
You might try using the adjustment range on your eyepieces to get things parfocal. Get the camera in focus, then see if there is sufficient adjustment range. If the eyepieces need to come out a bit, you could shim them. Is there any adjustment in your camera mount?

As for the 1.67x, I'd be inclined to spend the hefty price it's likely to fetch elsewhere - maybe a 20x DIC prism. Still, your high N.A. 20x SPlan Apo might do nicely with the 40x prism - how's it look?

Some people use the monitor for both scanning and picture taking. Others don't mind a wider view through the eyepieces and a cropped view in the camera. I'd try those options for a while, unless you find the 1.67x at a bargain price.

You have a great setup. The 100x Nikon, though, isn't quite perfectly compatible with your Olympus relay lens. The Nikon expects no eyepiece or camera corrections. The Olympus relay lens provides a bit. Might not notice it, but if you do you could probably sell the Nikon for what it will cost to get the Olympus.

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Re: My new Olympus BHS BH2

#10 Post by mintakax » Thu Aug 08, 2019 5:52 am

Tom Jones wrote:First, I'd suggest you peruse this site: http://www.krebsmicro.com/ Charlie Krebs is the BHS-DIC Photomicrography Guru. Pretty much all of your questions are answered there.

The projection eyepieces are designed to stay away from the outer edges of the field where image quality can be a bit less. The 2.5x is designed for full frame, and if you have the DI PA1-10A adapter, that's the correct one. The 1.67x does about the same, but the projected area is appropriate for an APS-C sensor. That's way too small for the full frame sensor in my opinion, although the SPlans are wide field so it may work out better than I imagine.

As PeteM suggested, a lower magnification objective would shrink the field a lot cheaper than the 1.67x. What he didn't mention is the addition of a BH-2 CA magnification changer such as this one:

https://www.ebay.com/itm/Olympus-BH-Ser ... Sw-1Zcgq5H

It also has the benefit of having a built-in Bertrand lens to help center your phase rings. You won't need a phase telescope.

I don't remember if there are vignetting problems using the mag changer along with the DIC intermediate tube. It's been awhile since I used mine that way. Mag changers are really nice to help with framing. I have a couple I use with my BHS-DIC system and BH-2 outreach scopes, and BX versions (U-CA) for my BX-50s.

I second the suggestion for an SPlan 20x if you don't already have one. They're very handy with pond life.

There are other ways to do it as well, but they will take some detective work on your part. No manufacturer I know of has a real 35mm full-frame sensor for video. Even Red uses Super 35. Matching field size to sensor size got a lot more difficult when the different aspect ratios and resolutions became available on the same sensor. Because of that, you are not using all of the sensor anyway, and the size varies, a lot, depending on the video resolution and aspect ratio you use. Each resolution/aspect ratio will have a different optimum projection set.

From Nikon for the Z6:
FX (36x24) image area: 6048 x 4024 (L: 24.3 million), 4528 x 3016 (M: 13.7 million), 3024 x 2016 (S: 6.1 million)
DX (24x16) image area: 3936 x 2624 (L: 10.3 million), 2944 x 1968 (M: 5.8 million), 1968 x 1312 (S: 2.6 million)
1:1 (24x24) image area: 4016 x 4016 (L: 16.1 million), 3008 x 3008 (M: 9.0 million), 2000 x 2000 (S: 4.0 million)
16:9 (36x20) image area: 6048 x 3400 (L: 20.6 million), 4528 x 2544 (M: 11.5 million), 3024 x 1696 (S: 5.1 million)

As an example, on my BHS I use a Panasonic GH4 camera and shoot 4K UHD. To get the best image I use a NFL 3.3x projection lens (to get any necessary eyepiece color correction) and a U-PMTVC 0.3x C-mount adapter to give me essentially direct projection (3.3 x 0.3 =0.99x), and fits very well. If I shoot instead 4K DCI, it doesn't fit as well.

Time to do a little research to figure out the best way to get what you need for what you are going to shoot.

Tom
Thank you Tom-- That Charlie Krebs site seems a gold mine, I'll study it for sure. I did yesterday read his article on elevating the photo eyepiece to scale down magnification.

I do have an Splan 20x and have been making good use of it.

I'll be shooting 4K FX and probably be scaling that to HD so I'll be able to avoid vignetted regions most of the time. I'm thinking that vignetting would be preferable to having vastly different scales between the camera FOV and eyepiece FOV. That mag changer may be the ticket, but I can't seem to find any info on how its used. A stupid question: where is it positioned in the optical train ?

Since you have a BHS -DIC system, I hope its OK to ask you a couple of questions:

1) According to Alan Wood's instructions, after setting up for Koehler using 10x, bright field, the prism slider (prism screwed all the way in) and polarizer are engaged, the Centering Telescope is inserted and the polarizer is rotated to make the interference fringe sharpest. The polarizer rotation adjuster limits rotation adjustment to only a few degrees. On my system, I can detect no change in the interference fringe through the entire range of adjustment. The fringe seems sharp, but I would have expected the adjustment to produce a noticeable effect ? Is this your experience ? I'm wondering if the polarizer in my DIC condenser unit is in the right rotation.

2) As I turn the prism screw such that the background gets darker, I notice a distinct gradient in the darkness... is this normal ?

3) The entire DIC condenser unit is held tight by one very small screw and the force required to rotate the turret is such that it disturbs the condenser center position. Is this your experience ? If not, is there any way to lubricate or lessen the force required to rotate the turret ?

Apologies if my questions are obtuse. Its difficult starting a new hobby, coming in as a complete beginner and attempting to communicate with the experts. I've been down that road several times in my life and it is very humbling ! 'm not adverse to research and have been doing quite a bit.

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Re: My new Olympus BHS BH2

#11 Post by MichaelG. » Thu Aug 08, 2019 6:08 am

mintakax wrote:Its been a fun few days setting up this new (to me) microscope. It is an Olympus BHS BH2 with Phase and DIC. I don't have any Phase objectives (yet) so I haven't had a chance to try that part. I have been playing with the DIC quite a bit.

[ ... ]

I'm having a blast :D
What a tremendous start !!
Thanks for sharing your joy.

MichaelG.
Too many 'projects'

MicroBob
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Re: My new Olympus BHS BH2

#12 Post by MicroBob » Thu Aug 08, 2019 7:30 am

Hi Dan,
you've got yourself a very nice setup there and the results look very promising!
Your approach with the well slides makes it more difficult for you but at the same time you obain a more natural view of the specimens with makes it worth the effort. Most "great" plancton images are made in thinnest water layers and your technique will offer a very attractive alternative once you have mastered it.
According to the camera: It would be an alternative to use a pancake camera lens of 50 to 60mm and an eyepiece and have the image cover the whole area with the image corners just touching the edge of the image circle.

In a finity system (like 160mm) the adjustable eyepiece tubes are intended to correct tube lenght after setting the pupil distance. Some higher corrected objectives won't perform optimal when you move away from the true tube lenght in this case. In this case you might alter the camera tube a bit more than necessary and then shim the projective until it is perfectly parfocal.

Bob

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Re: My new Olympus BHS BH2

#13 Post by Hobbyst46 » Thu Aug 08, 2019 7:54 am

mintakax wrote:https://vimeo.com/352578557
I'm having a blast :D
An excellent setup. SPlans yield beautiful images. And the video is very attractive, too! enjoy!
Is that a 100W halogen illuminator ?
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

mintakax
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Re: My new Olympus BHS BH2

#14 Post by mintakax » Thu Aug 08, 2019 11:19 am

MichaelG. wrote:
mintakax wrote:Its been a fun few days setting up this new (to me) microscope. It is an Olympus BHS BH2 with Phase and DIC. I don't have any Phase objectives (yet) so I haven't had a chance to try that part. I have been playing with the DIC quite a bit.

[ ... ]

I'm having a blast :D
What a tremendous start !!
Thanks for sharing your joy.

MichaelG.
Thanks Michael !

mintakax
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Re: My new Olympus BHS BH2

#15 Post by mintakax » Thu Aug 08, 2019 11:29 am

MicroBob wrote:Hi Dan,
you've got yourself a very nice setup there and the results look very promising!
Your approach with the well slides makes it more difficult for you but at the same time you obain a more natural view of the specimens with makes it worth the effort. Most "great" plancton images are made in thinnest water layers and your technique will offer a very attractive alternative once you have mastered it.
According to the camera: It would be an alternative to use a pancake camera lens of 50 to 60mm and an eyepiece and have the image cover the whole area with the image corners just touching the edge of the image circle.

In a finity system (like 160mm) the adjustable eyepiece tubes are intended to correct tube lenght after setting the pupil distance. Some higher corrected objectives won't perform optimal when you move away from the true tube lenght in this case. In this case you might alter the camera tube a bit more than necessary and then shim the projective until it is perfectly parfocal.

Bob
Thanks Bob. Can the afocal technique be used with the 2.5x photo eyepiece through the photo tube ? I tried this yesterday with every lens in my house (none were pancake 50mm) and could not get a satisfactory image.

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Re: My new Olympus BHS BH2

#16 Post by mintakax » Thu Aug 08, 2019 11:30 am

Hobbyst46 wrote:
mintakax wrote:https://vimeo.com/352578557
I'm having a blast :D
An excellent setup. SPlans yield beautiful images. And the video is very attractive, too! enjoy!
Is that a 100W halogen illuminator ?
Thank you ! Yes, it is the 100 Watt.

Hobbyst46
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Re: My new Olympus BHS BH2

#17 Post by Hobbyst46 » Thu Aug 08, 2019 11:59 am

mintakax wrote:
Hobbyst46 wrote:
mintakax wrote:https://vimeo.com/352578557
I'm having a blast :D
An excellent setup. SPlans yield beautiful images. And the video is very attractive, too! enjoy!
Is that a 100W halogen illuminator ?
Thank you ! Yes, it is the 100 Watt.
Excellent illumination then. I believe it will not cause any heat problems.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

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Re: My new Olympus BHS BH2

#18 Post by Tom Jones » Thu Aug 08, 2019 4:00 pm

Hi Dan,

Give me a couple of days to check on the Mag changer/DIC compatibility and your other DIC questions. I'm off to Hollywood this morning to do some video photomicrography training with a film maker friend in her studio, so I won't be able to play with my BHS until at least tomorrow or Saturday.

Tom

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Re: My new Olympus BHS BH2

#19 Post by 75RR » Thu Aug 08, 2019 6:44 pm

Can the afocal technique be used with the 2.5x photo eyepiece through the photo tube ? I tried this yesterday with every lens in my house (none were pancake 50mm) and could not get a satisfactory image.
It won't work with a projection eyepiece, it needs a normal eyepiece. You can test this by using one of your binocular eyepieces. Make sure it is parfocal with the binocular.
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Re: My new Olympus BHS BH2

#20 Post by Hobbyst46 » Thu Aug 08, 2019 7:25 pm

mintakax wrote:...
For afocal with a 10X eyepiece, the appropriate camera lens should be a 63mm, according to:
http://www.photomacrography.net/forum/v ... 9265#99265
Although those calculations were demonstrated for a DSLR, not a mirrorless camera.
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Re: My new Olympus BHS BH2

#21 Post by MicroBob » Thu Aug 08, 2019 7:28 pm

mintakax wrote: (none were pancake 50mm)
Hi Dan,
the idea behind the pancake lens is that is is possible this way to put the entrance pupil of the objective at the place of the exit pupil of the eyepiece (high eyepoint). A 50mm Zeiss Tessar mit M42 mount might work and is cheap. Or an other flat 4-lenser, perhaps a 55mm or 58mm. There are different opinions how important the quality of the camera lens is. Zeiss used a simple 60mm achromat (two lenses!) and this was deemed good enough at the time. 60mm camera lenses are quite rare.

Bob

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Re: My new Olympus BHS BH2

#22 Post by MicroBob » Thu Aug 08, 2019 8:08 pm

Your video is very nice!

Can someone identify the animal that is shown from second 32 on - I have never seen this before.

Bob

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Re: My new Olympus BHS BH2

#23 Post by MichaelG. » Fri Aug 09, 2019 8:13 am

MicroBob wrote:There are different opinions how important the quality of the camera lens is. Zeiss used a simple 60mm achromat (two lenses!) and this was deemed good enough at the time. 60mm camera lenses are quite rare.
Please forgive my pedantry, Bob ...
The Zeiss attachment incorporates an objective [sic] of 63mm focal length.
That same simple achromat may feature elsewhere in the Zeiss catalogue ... ???

http://cholla.mmto.org/minerals/photos/ ... o_35mm.pdf

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Re: My new Olympus BHS BH2

#24 Post by Hobbyst46 » Fri Aug 09, 2019 8:25 am

MichaelG. wrote:
MicroBob wrote:There are different opinions how important the quality of the camera lens is. Zeiss used a simple 60mm achromat (two lenses!) and this was deemed good enough at the time. 60mm camera lenses are quite rare.
Please forgive my pedantry, Bob ...
The Zeiss attachment incorporates an objective [sic] of 63mm focal length.
That same simple achromat may feature elsewhere in the Zeiss catalogue ... ???

http://cholla.mmto.org/minerals/photos/ ... o_35mm.pdf

MichaelG.
Michael, thanks for the link!! it is a very useful document although belongs to the film era!

Now I see why it was said that the original Zeiss approach was "afocal": the 63mm "objective" (lens between the eyepiece and camera) in their adapter is used with an eyepiece, just as an "ordinary" 63mm camera objective (from the camera firm or compatible, and the closest available focal length) would serve with eyepiece.
Last edited by Hobbyst46 on Fri Aug 09, 2019 11:11 am, edited 1 time in total.
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Re: My new Olympus BHS BH2

#25 Post by MicroBob » Fri Aug 09, 2019 8:55 am

Hi Michael,
from the 160mm system I remember that this Zeiss 63mm thing does the same job as a camera lens (=objective) in an afocal setup. Probably you could even take a landscape picture with it when used off the microscope. As far as I know this wasn't a complicated design like a 6-lens 50mm 1:1,4 usually is but just an achromat.

On the other hand side I was just a couple of days told that a complicated 8-lens camera lens would be just right - by someone who should know it and has a lot of experience. :?:

Bob

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Re: My new Olympus BHS BH2

#26 Post by MichaelG. » Fri Aug 09, 2019 1:56 pm

MicroBob wrote:Hi Michael,
from the 160mm system I remember that this Zeiss 63mm thing does the same job as a camera lens (=objective) in an afocal setup. Probably you could even take a landscape picture with it when used off the microscope. ...
Exactly

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Re: My new Olympus BHS BH2

#27 Post by MichaelG. » Fri Aug 09, 2019 2:01 pm

MicroBob wrote: ... On the other hand side I was just a couple of days told that a complicated 8-lens camera lens would be just right - by someone who should know it and has a lot of experience. :?:
Likewise ... a Rolls Royce might be 'just right' if you want to kill a pig :D

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Re: My new Olympus BHS BH2

#28 Post by MichaelG. » Fri Aug 09, 2019 2:17 pm

Hobbyst46 wrote:Now I see why it was said that the original Zeiss approach was "afocal": the 63mm "objective" (lens between the eyepiece and camera) in their adapter is used with an eyepiece, just as an "ordinary" 63mm camera objective (from the camera firm or compatible, and the closest available focal length) would serve with eyepiece.
There is a good [historical] reason for zeiss using a focal length of about 63mm
Anything shorter than that would likely need to be of retrofocus design [see MicroBob's post] to work with the 35mm SLR cameras of the day ... This would unnecessarily complicate the lens design [as per my pig-slaying Rolls Royce].

Things are different now, with mirrorless camera bodies having short flange-to-sensor distance.

MichaelG.
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Re: My new Olympus BHS BH2

#29 Post by MicroBob » Fri Aug 09, 2019 2:28 pm

I have tree different cameras and use them for the microscope in afocal mode. For each I use the best camera objective I was able to get hold of for not too much money:
Pentax Q7 - 8,5mm 1:1,9 (short because of the little focal lenght)
Nikon 1J5 - 18,5mm 1:1,8 (short because of the little focal lenght)
Sony A6000 - Pentax M 40mm 1:2,8 (a pancake design)

I haven't compared them to other objectives as there are no real alternatives for the former two and the third is well respected for the purpose. And they do work well. It would be interesting to know how a simple achromat would work in comparison as this would open new options for the adaptation.

A quick search brought this result: https://de.aliexpress.com/item/32977202 ... b201603_53

And here a cheap 39,5mm: https://www.edunikum.de/sehen-licht-und ... mm/a-5710/

Bob

MichaelG.
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Re: My new Olympus BHS BH2

#30 Post by MichaelG. » Fri Aug 09, 2019 3:13 pm

MicroBob wrote:... And here a cheap 39,5mm: https://www.edunikum.de/sehen-licht-und ... mm/a-5710/
In principle, Bob, I think that should work very nicely on Micro 4/3
... and it's certainly an attractive price !!

Note: the one on AliExpress is 500mm focal length ... I wouldn't have room to use that.

MichaelG.
Too many 'projects'

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