Mitutoyo HR Objectives and pixel size

[deberle]

Greetings,

I recently came across a seemingly too good to be true deal on a new Mitutoyo 10X HR objective (378-788-15). Besides being wary of such a deal, I rationalized that the .6um resolution wouldn't benefit my images because my SonyA7R5 has a pixel size of 3.76um. In reviews by the late Robert O'Toole, he claimed the resolution on the sensor is the magnification factor times the resolution. When I called Edmund Optics, they said that even though they'd like to sell me a more expensive product, they didn't think I'd benefit from the finer resolution given my sensor. I've seen Robert's review of the 5X HR, but was never able to access his review of the 10X HR objective. Does anyone have experience with it and can they verify Robert's math? I don't want to break any rules of the forum by posting the location of this deal, but if anyone is interested, let me know and we'll find a way to get you the information.

-Dave

[Scarodactyl]

I had one for a while and I could definitely see the difference vs a normal 10x.

[bbobby]

... I rationalized that the .6um resolution wouldn't benefit my images because my SonyA7R5 has a pixel size of 3.76um...

Divide the 0.6 by 2 for pixel size... I think for green light (0.550) the theoretical limit is 0.65 and mitutoyo.eu shows resolution for M Plan Apo HR 10X to be 0.7 µm... 10x NA 0.42 objective is outresolving your sensor actually... you will need ~3.3 µm pixel size...

10x NA 0.28 needs "only" 4.9 µm pixels so there will be at least theoretically bump in resolution. I am sure it will be visible especially with pixel shift... On the other hand if you push regular 10/.28 down to 7.5x you will hit the resolution limit of this sensor and to spend thousands more for HR you either have to be rich or really need 10x ;-)

[CrispyBee]

Think of it this way:

10x 0.28 = f17,9
10x 0.42 = f11,9

On fullframe that's roughly the difference between 12MP and 19MP of resolution.

However you end up cutting your WD from 35mm to 15mm. There's no free lunch.

Also: if a deal seems to good to be true, it usually is.

[Lou Jost]

Personally I don't believe there are any precise rules determining a specific hard cut-off based on sensor size. Resolution ALWAYS depends on both the sensor resolution and the image resolution. Just as in film. An increase in image resolution will have an effect on the quality of the final image, even if the pixel size is below the resolution of the image. Of course the effect could be very small if there is a big mismatch between the two, but there is no hard cut-off.

Also, the nominal pixel size of your camera is not the relevant number anyway, as bbobby explains.

[Chris S.]

I don't want to break any rules of the forum by posting the location of this deal, but if anyone is interested, let me know and we'll find a way to get you the information.

Dave,

A post informing the community of an offer you think is good, and that you don't benefit from, would usually not break our rules. We do forbid commercial activity, but sharing information constructively is fine. (This sometimes requires a judgement call, but we can handle that.)

I agree, of course, that deals that seem too good to be true are usually just that. But it will be interesting to see what you've found.

--Chris S.
(Admin team)

[deberle]

Ok Chris,

I didn't want to cross a line being new here. The offer is at the link below. I did a chat with the seller and he says they are new from Mitutoyo Austria. Let me know if anyone purchases one and please post the results.
-Dave
https://www.mjkzz.de/products/mitutoyo- ... 6355837028

[CrispyBee]

Ok Chris,

I didn't want to cross a line being new here. The offer is at the link below. I did a chat with the seller and he says they are new from Mitutoyo Austria. Let me know if anyone purchases one and please post the results.
-Dave
https://www.mjkzz.de/products/mitutoyo- ... 6355837028

Oh well if you can afford it, go for it. As long as you know what you're getting into and what to expect.

MJKZZ Europe / Daniel Puschina is a very reliable sellers, though it sometimes takes a long time for the products to ship, they always ship in the end

I thought you meant like a <1000$/€ kind of deal. Recently there's been a post regarding a rather dubious webshop with super low prices but the link you've posted is 100% genuine and trustworthy.

[Chris S.]

Dave,

Nothing wrong with sharing that link.

As to whether the price is "too good to be true," I would want to know if the lens comes with a return privilege, if the vendor is an authorized Mitutoyo seller and has a good record of customer service, and if you have the means to test the lens. Also, I would want to know if this is the current model of the Mitutoyo HR 10/0.42 objective. The image shown in the offering looks like a style I associate with an earlier model; see Edmund Optics for the current style. So far as I've heard, the older style HR objectives are optically excellent--but a "new old stock" specimen might explain the sale price.

This is indeed a low price for a new Mitutoyo HR 10x, if you are buying from a factory authorized seller with a good record of standing behind lenses. On the other hand, it would be a high price for a used specimen or one that was internally out of alignment--something that is not uncommon.

As to the resolution and magnification: If you were to test a 10/0.42 objective (like the Mitutoyo HR) against a 10/0.28 objective (like the "regular" Mitutoyo) on your camera, I think you'd see a difference. Whether that difference would be worth the cost to you, I can't say.

Even at the discounted price, this objective costs $4000 more than the 10/0.28. Is it $4000 better? That's your call, of course. Also there is a cost in working distance, as CrispyBee pointed out--but 15mm is still a lot of WD. One last cost is the need to take about three times more images, given the HR's shorter depth of field, and the processing time to stack them. (Though if your stacking is automated and you have a decent computer, these are not a big deal.)

Do recall that some good photographers shoot the regular 20x/0.42 Mitutoyo on a shorter converging lens (aka "tube lens") and obtain something approaching what the HR 10x should provide.

If money were no object, I would have a complete set of Mitutoyo HR objectives to go with the complete set of regular Mitutoyo objectives I have now. I would pick and choose as needed. Alas, there are more lenses I want than I can cost justify; consequently, I have no HR lenses.

Best,

--Chris S.

[CrispyBee]

Do recall that some good photographers shoot the regular 20x/0.42 Mitutoyo on a shorter converging lens (aka "tube lens) and obtain something approaching what the HR 10x should provide.

If money were no object, I would have a complete set of Mitutoyo HR objectives to go with the complete set of regular Mitutoyo objectives I have now. I would pick and choose as needed. Alas, there are more lenses I want than I can cost justify; consequently, I have no HR lenses.

Best,

--Chris S.

Good point - depending on the sensor size a short tube lens with a 20x 0.42 would be a better and more cost-effective solution with even more WD - though as you pointed out, the 15mm of the HR aren't too bad, it's better than my setup with its 8-9mm.

[deberle]

Thank you everyone for your replies. In the end I went with the standard 10X .28NA. The larger working distance as noted was also a factor. Does anyone have the password to Robert O'Toole's review of the 10X HR? I'd still be curious to know what conclusions he arrived at.

-Dave

[Lou Jost]

Thank you everyone for your replies. In the end I went with the standard 10X .28NA. The larger working distance as noted was also a factor. Does anyone have the password to Robert O'Toole's review of the 10X HR? I'd still be curious to know what conclusions he arrived at.

-Dave

I bought a very reasonably priced 10x HR on eBay a few months ago and it was badly misaligned. I have found some ways to reduce the effect of the problems, but I still feel burned. Because it was delivered to my family's address in the US and I could not pick it up from there until after the return period had passed, I could not return it.

One way to help reduce the effect of any misalignment is to use a medium format tube lens with a shift adapter. You can then map out the region of best sharpness for the objective and move that to the center. Then make a series of shots at different camera azimuths to figure out the best alignment for the long axis of the sensor. It improves the image significantly. (I should add that medium format tube lenses are generally much better than normal tube lenses if one is shooting FF.)

[IMAGOμM]

One way to help reduce the effect of any misalignment is to use a medium format tube lens with a shift adapter. You can then map out the region of best sharpness for the objective and move that to the center. Then make a series of shots at different camera azimuths to figure out the best alignment for the long axis of the sensor. It improves the image significantly. (I should add that medium format tube lenses are generally much better than normal tube lenses if one is shooting FF.)

I'm afraid I don't quite understand this procedure. The format covered by a Mitutoyo Apo is FF, with some difficulty. To increase it I have to use a pushing-up tube lens (well, a MF or LF as you suggest). Then, by moving the lens or the sensor, I can identify the areas most affected by the misalignment. However, it seems to me that all this is equivalent to using a tube lens of nominal focal length and then cropping the most deteriorated areas, obviously taking this into account when shooting.
Evidently I'm missing something.

[Lou Jost]

One way to help reduce the effect of any misalignment is to use a medium format tube lens with a shift adapter. You can then map out the region of best sharpness for the objective and move that to the center. Then make a series of shots at different camera azimuths to figure out the best alignment for the long axis of the sensor. It improves the image significantly. (I should add that medium format tube lenses are generally much better than normal tube lenses if one is shooting FF.)

I'm afraid I don't quite understand this procedure. The format covered by a Mitutoyo Apo is FF, with some difficulty. To increase it I have to use a pushing-up tube lens (well, a MF or LF as you suggest). Then, by moving the lens or the sensor, I can identify the areas most affected by the misalignment. However, it seems to me that all this is equivalent to using a tube lens of nominal focal length and then cropping the most deteriorated areas, obviously taking this into account when shooting.
Evidently I'm missing something.

If the objective is decentered, the sensor or tube lens has to be shifted so that the center of the sensor captures the best part of the image. Then and only then, will the four corners be equal to each other in resolution. Cropping will reduce the image quality, and you may actually miss parts of the aerial image that are usable, because you never imaged them with the sensor.

[IMAGOμM]

If the objective is decentered, the sensor or tube lens has to be shifted so that the center of the sensor captures the best part of the image. Then and only then, will the four corners be equal to each other in resolution. Cropping will reduce the image quality, and you may actually miss parts of the aerial image that are usable, because you never imaged them with the sensor.

Thanks for the suggestion and the subsequent clarification, now it's all clear to me. I hadn't considered that this trick is valid for lenses that are not perfectly aligned. I will mount an LF lens as a tube lens for a defective Mitutoyo bought used and that I couldn't check in time, as happened to you. Although I doubt that the defect I found is due to a simple misalignment. However, trying doesn't hurt and I will use it on my Horseman modified for Canon Eos EF cameras.