Variable Magnification Mitutoyo 5x

[Jampay Dorje]

Thought I would share this, it’s a variable magnification macro lens I made for hand held macro in the field. It has a range of around 3-5x and seems to have excellent performance through the range. It’s nothing novel just using the Raynox 250 in normal orientation. When the the lens is at its shortest it is somewhere around the infinity focus of the raynox and at full extension it is around 200mm I guess. I wasn’t trying to hit any magic numbers for the focal length it’s more about practicality and versatility in the field. I don’t see much difference in image quality throughout the range but I do have to say that I haven’t looked too closely.

If anyone is interested in more details I can post the plans. It’s not difficult to make but does require a lathe and a resin 3d printer which makes a bit of a barrier for most people.

The photos show it at shortest length, longest length and with a custom diffuser for the Godox MF12. The diffuser is excellent and I will make a post about that soon.

Hope everyone is doing well

[dolmadis]

Interesting post, thanks. I would be pleased to see your working plans for metal work and download 3D Resin Print file.

Best, John

[allanwalls]

Hi Jampay,

This is a very interesting device and uses a basic lens configuration that has been the subject of much discussion in recent weeks. I just happen to have the same arrangement of optics in use right now, evaluating the performance of the 5X objective at short focus. Lacking any formal training in the area, I am having trouble understanding how this device is even able to focus an image on the sensor as it is moved away from the sensor. The DCR250 has a focal length of 125mm and produces a sharp image with the Mitutoyo M-plan objectives when it is situated in the normal orientation at 124mm from the sensor (with my copy of the lens, st least), but surely extending the tube length, with no other adjustments, like shortening the subject distance, will mean the image is formed at a progressively greater distance in front of the sensor. Are you also changing the subject distance form the end of the objective, and if so, by how much? Are you seeing any change in image quality or degradation in chromatic or geometric corrections? I would love to see some of the images you are obtaining with this device at full extension. I am on the middle of something right now but will give this technique a trial run as soon as possible. Thanks for posting this interesting piece.

Best,

Allan

[Scarodactyl]

It will certainly change working distance, it's just having the mitutoyo act as a finite objective.

[lothman]

If anyone is interested in more details I can post the plans. It’s not difficult to make but does require a lathe and a resin 3d printer which makes a bit of a barrier for most people.

sorry to bother but you could have very similar results with the Laowa 2,5-5x at a fraction of costs. The Laowa can be used also on full frame, not so a pushed down Mitutoyo 5x.

[Adalbert]

Hi,
Very nice!
I prefer the solution with the Canon EF 70-200L as a tube lens.
So, you can change the magnification a little bit and use focus bracketing.
https://www.facebook.com/photo/?fbid=17 ... 0269581589
Best, ADi

[Jampay Dorje]

Hi Jampay,

This is a very interesting device and uses a basic lens configuration that has been the subject of much discussion in recent weeks. I just happen to have the same arrangement of optics in use right now, evaluating the performance of the 5X objective at short focus. Lacking any formal training in the area, I am having trouble understanding how this device is even able to focus an image on the sensor as it is moved away from the sensor. The DCR250 has a focal length of 125mm and produces a sharp image with the Mitutoyo M-plan objectives when it is situated in the normal orientation at 124mm from the sensor (with my copy of the lens, st least), but surely extending the tube length, with no other adjustments, like shortening the subject distance, will mean the image is formed at a progressively greater distance in front of the sensor. Are you also changing the subject distance form the end of the objective, and if so, by how much? Are you seeing any change in image quality or degradation in chromatic or geometric corrections? I would love to see some of the images you are obtaining with this device at full extension. I am on the middle of something right now but will give this technique a trial run as soon as possible. Thanks for posting this interesting piece.

Best,

Allan

Hi Allan. Thanks for your questions and interest in the project, I will be interested to hear what your findings are if you test this yourself. I wanted to thank you for all the work you have done supporting the macro community. You have brought happiness to so many people including me!

Here are some tests I made for you this morning. I tested the lens ant the extemes of magnification and somewhere around the middle. Please note I have no idea how this lens works, I just built it and tested it. I am not really sure how to make a test shot. I found a fly in the house which had some very fine hairs, I figured this might make a good test for resolution. There is also a tiny Australian jumping spider I photographed outside on my hand. There is also 100% crop from a small fly (with green eyes) I photographed outside at 4.8x I think this image shows the sharpness of the lens the best. All the crops are at 100%. Sorry the photos are in random order, I couldn't work out how to change their order.

Working distance from the front of the objective is 30mm at 4.8x. 32mm at 4x. 35mm at 3.2x.

I hope this helps.

Best wishes, Ben

[Jampay Dorje]

Interesting post, thanks. I would be pleased to see your working plans for metal work and download 3D Resin Print file.

Best, John

Hi John. Here are some pictures for you. Sorry I cant take it fully apart, it is glued during assembly and I didnt take any photos prior to assembly. In the design drawings the Raynox is represented by the crudely modeled top part. The Raynox is press fit into the helical section. Not shown are the 4 pins that locate in the helical thread that form the drive mechanism for the 'zoom' function. 1 full rotation extends the magnification from approx 3 to 5x.

The inside surfaces are painted with Musou Black and Tesa Cloth Tape lines the sliding surfaces creating a bearing surface and also blocking light and providing a bit of a filter from dust ingress as the lens is extended.

The main plastic part is the helical section. It would be better made from metal but I have no easy way to machine a thread with a 100mm pitch. The thread is a 4 start with square section to accept the 'thrust pins'. The other plastic parts are the inner cylinder which is there to provide a non reflective surface as the lens extends. The other part is the outer ring which is used to twist the lens to enable it to extend.

I think a way simpler version would be to make slide telescopically, I chose the helical design mainly as I was interested in the design and construction challenge. One of my main goals was to make this as light as possible to allow high magnification macro hand held in the field.

Main body is made from Aluminium tube with a reversing ring attached to the end to mount it to the camera body.

I hope this helps,
Best Wishes,
Ben.

[Sym P. le]

Without having read too much of this (I hope I'm on track), I can say that I have always used my TU Plan 10x on short tube lenses. I do this for compactness and ease of use in the field. I have never felt a lack of acuity to be an issue since the photo quality was just so far beyond anything I could imagine. Regretfully, since it was the lens that was on the camera when I slipped and slammed it into the ground, until I replace it I can't post anything new that would represent the best of the objective.

What I don't understand about this setup is that once the Raynox is away from infinity focus, how the system can manage to focus anything. The short tube lenses I use are always set to infinity. This will be another project, examining the effects of de-focusing the tube lens.

[Scarodactyl]

What I don't understand about this setup is that once the Raynox is away from infinity focus, how the system can manage to focus anything.

An infinity objective doesn't only work when producing an image focused at infinity, it is just optimized for those conditions. You can use a mitutoyo 5x with no tube lens at all--it changes the working distance and introduces aberrations but it will produce an image. You can get away with this kind of optical shenanigan more at lower magnifications and NAs and in some cases even improve image quality (presumably since objectives are also constrained to a certain parfocal length and potential microscope accessory layout, conditions which you can sacrifice in macro work).

[Jampay Dorje]

If anyone is interested in more details I can post the plans. It’s not difficult to make but does require a lathe and a resin 3d printer which makes a bit of a barrier for most people.

sorry to bother but you could have very similar results with the Laowa 2,5-5x at a fraction of costs. The Laowa can be used also on full frame, not so a pushed down Mitutoyo 5x.

Thank you, I am aware of the Laowa but haven't tested it so I cant speak to image quality. A second hand Mitutoyo in Australia was about the same cost as the Laowa. I think the first reason I wanted to try this is that I like to design and make things. Secondly my goal is to be able to shoot up to 10x hand held in the field. So i designed and tested this lens with that goal in mind of eventually using the Mitutoyo 10x.

The 10x should give me a range of 6-10ish and will give maximum versatility in the field without having to change lenses too often potentially losing the subject. In addition to that this is a very light weight and compact design, I think fatigue photographing the very small is a real consideration in the field. I particularly value the small size of the microscope objective lenses which enable the camera to be very close to the eye level of ground insects, I like how this enables the photos to be shot from the insects perspective rather than from above. In addition to this the small size of the objective makes it much easier to find the insect through the lens at high magnification as there is much less in front to you obstructing their location. Finally there is the matter of diffusion, I am able to make a 3d printed diffuser that provides almost a full half hemisphere of illumination (including front illumination) with a very small opening for the lens, I like the way this looks in the eyes of subjects like jumping spiders. I think this would be difficult with the Laowa.

Thanks for your question I hope this helps,
Best wishes,
Ben.

[lothman]

I think this would be difficult with the Laowa.

I have both and I disagree In the field the Laowa is much more handy than your setup (tripod collar available, LED ring light available, fast and easy magnification change, being able to close the aperture a bit for a bit higher DOF...) and by extension ring you can also push up to 7x magnification. You can use the same illumination equipment.
Although I appreciate experimenting since I'm a mechanical engineer, but after decades I have to admit that buying a used Laowa 2,5-5x gave me better results, faster setup even on demanding full frame sensors than everything else I sticked together in this magnification range <5x (stacked lenses, reversed lenses, Nikon/Minolta scanner lenses...). And a good thing is, that I can resell the Laowa at a good price, so only small losses.

Here in Europe a good used 5x Mitutoyo is over 400€ and for such an offer you have to hunt ebay for a year. You also still need the Raynox tube lens, tubes, adapters, clamps... so another 100€. On the other hand the Laowa can be found between 350-400€ because lot of people bought this lens and weren't aware that focus bracketing is necesarry at such magnifications.

But at 5x my Mitutoyo is a tad better than the Laowa @5x, but at 2,5x the Laowa still shines on Pixel-Shift with a Sony A7riv with 60 MP on full frame.
http://www.photomacrography.net/forum/v ... 39#p283039

best regards
Lothar

[RobertOToole]

If anyone is interested in more details I can post the plans. It’s not difficult to make but does require a lathe and a resin 3d printer which makes a bit of a barrier for most people.

sorry to bother but you could have very similar results with the Laowa 2,5-5x at a fraction of costs. The Laowa can be used also on full frame, not so a pushed down Mitutoyo 5x.

Just FYI, I tested the Laowa LAOWA 25MM F/2.8 2.5-5X ULTRA vs the Mitutoyo M Plan APO 5x / 0.14 in January 2022 at 5x.

To be honest I had to check, I forgot about the results already!

https://www.closeuphotography.com/laowa ... -lens-test

Spoiler alert

The Mitutoyo beat the Laowa in the center and APS-C corners but the Laowa was better in the corners on a full frame Sony A7RIV.

FWIW I don't get paid by selling Laowa lenses, I don't use referral links, I don't get any commission from Laowa, I don't sell visitor tracking stats from my site. Just sharing my test results. That said I've been impressed by IQ from every Laowa lens I've tested so far.

Best,

Robert

[lothman]

The Mitutoyo beat the Laowa in the center and APS-C corners but the Laowa was better in the corners on a full frame Sony A7RIV.

My copy of the 5x Mity beats my copy of Laowa in the center and in the corners of full frame, see fullrez images here:
http://www.photomacrography.net/forum/v ... 39#p283039

but my consclusion is the same than yours, this tiny bit of better picture quality is not worth double the money in most occasions. One may not forget that those silicone wafers are a brutal target which reveil the smallest imperfection of a lens. For a picture uf a butterfly wing both would give you excellent big prints.

[RobertOToole]

but my consclusion is the same than yours, this tiny bit of better picture quality is not worth double the money in most occasions. One may not forget that those silicone wafers are a brutal target which reveil the smallest imperfection of a lens. For a picture uf a butterfly wing both would give you excellent big prints.

I agree 100% Lothar!

In-the-field shooting spiders on flowers a macro lens from the 1980s will make a beautiful images on an A7RIV.

Best,

Robert