Too good to be?

[dhmiller]

When people see something like this listing for a Mity 20x for around $500, would they tend to be skeptical? US seller with 100% returns... Or are good deals on used equipment regularly found? https://www.ebay.com/itm/233367507629

[zed]

Used optics like this a very much a crap shoot. If you are confident in your ability to accurately test objectives like this - and the seller offers returns - it might be worth the gamble.

This one looks better

[dhmiller]

Thanks Zed. The one you linked to is just a bit under a new price, so I wouldn't go for that.
I'm curious if there are people who test objectives for a fee... will post a note here to that effect.
-Dennis

Used optics like this a very much a crap shoot. If you are confident in your ability to accurately test objectives like this - and the seller offers returns - it might be worth the gamble.

This one looks better

[Chris S.]

When people see something like this listing for a Mity 20x for around $500, would they tend to be skeptical? US seller with 100% returns... Or are good deals on used equipment regularly found?

I would be skeptical, but not without hope. So long as “trust but verify” is possible, one can indeed get good deals. As you say, this seller has good feedback. And there is a 14-day return privilege.

This particular objective is a bit rough cosmetically, but that indicates absolutely nothing about its optical capability. For that, you need to test.

I'm curious if there are people who test objectives for a fee... will post a note here to that effect.

I fear the only person who routinely tests these objectives for others is me. I don’t charge a fee, but my watch sometimes reads in centuries, my calendar in geologic time. We can communicate offline about this particular objective and what epoch my calendar is in.

This one looks better

Cosmetically, it certainly looks better, of course at a much higher price. But note the all-important deal-killer: Seller does not offer returns. From experience testing lots of Mitutoyo objectives, I warn people to never, ever buy one without the chance to test and return it if necessary, no matter how nice it looks.

Some will note that since this objective is described as "an item in excellent, new condition with no functional defects," one might insist on a return on the basis of "item not as described." That’s likely possible—eBay generally sides with buyers. But in my opinion, if a seller clearly states that he doesn’t want to mess with returns, we should respect that if possible. (Though I think it’s OK to message the seller through official eBay channels before buying, request an exception to the policy, and explain under what conditions one would return it; if the seller agrees to this on record in advance of purchase, no problem.)

--Chris S.

[Macro_Cosmos]

FYI the Mitutoyo M Plan 20x is the worst to buy used. Even new ones will likely kill itself after 3-5 years of use, that's if you get a good sample. It puts out great images, sure, but the build quality and sample control is horrendous.

Someone I know got 10 of them new, returned 7 due to various weird problems (2 or so had web-like substrate it them, presumably it's from the cemented doublet?). 2 out of 3 died in 5 years. I have the remaining one and it decentered itself.

The one in the listing you showed is a rather old model. The front element looks fine but I think it has been abused, albeit not much.

You can see some clear chipping.


I think the seller is trustworthy. He or she is obviously honest enough to show these high resolution photos of blemishes. 100% with returns, sure. Give it a go, it might be absolutely perfect optically. Worst case you lose the shipping cost for returns.

Not sure about the old 20x Mits, the scary stuff I've cited above only applies to the newer model.

[Chris S.]

You can see some clear chipping.

But note that none of those chips are in the lens element; they are all in the black (epoxy?) ring around the element. These never have any optical effect, in my experience.

FYI the Mitutoyo M Plan 20x is the worst to buy used. Even new ones will likely kill itself after 3-5 years of use, that's if you get a good sample. It puts out great images, sure, but the build quality and sample control is horrendous.

I must violently disagree. My Mitty 20x is used, and I’ve tested more used specimens than I've bothered to count. Sure, some of them arrive in bad optical condition and need to be returned (I assume they have experienced "fall or drop” as Mitutoyo warns against. All the ones that have tested well have remained stable since testing, so far as I know. In my experience, Mitutoyo objective build quality and sample control are excellent. Among new specimens, every sample I’ve tested has been fine (though under serious pixel peeping, no two objectives I’ve ever seen are identical). I can’t imagine a good specimen “killing itself” after 3-5 years of use, unless it is abused. Granted, Mitutoyo objectives seem less tolerant of abuse than other objectives I’ve seen; my guess is that robust resistance to jarring is perhaps traded off by Mitutoyo for cylinder thinness and ease of lighting around.

I have never seen a Mitutoyo objective delaminate. Neither have I seen one decenter itself without apparent trauma inflicted by a user. I don’t know what happened with the ten specimens of your acquaintance, but am fairly sure that his/her report is far from representative of the Mitutoyo 20x, or any other Mitutoyo objective.

--Chris S.

[dmillard]

I have to confess that several years ago, one early but memorable morning, I fumbled a Mitutoyo 10x objective when I was screwing it into position. It fell through my fingers just a short distance to the counter top, and suffered no visible marks on the surface of the glass or barrel. However, the images it produced looked just a little soft when I tested it, unlike the results I had gotten previously from this objective. I bought another to compare, and the images were much sharper, confirming my doubts. I sold the damaged objective "For parts/repair".

Although this was a 10x, not a 20x objective, I am sure they are just as susceptible to misalignment from minor knocks or bumps, which is why Mitutoyo includes a warning label on the objective vials, and why I would never buy one without the seller offering a possible return if you were dissatisfied.

However, like Chris S, I have never observed spontaneous, autonomous delamination or decentering in any of the six Mitutoyo objectives I currently own.

[Lou Jost]

note that none of those chips are in the lens element; they are all in the black (epoxy?) ring around the element. These never have any optical effect, in my experience.

While that's true, something serious happened to that lens to put those dents in those places, and not just once. I'd stay away from it.

While we're confessing our lens abuse, I must confess I picked up my 10x Mitutoyo in its nice padded case from my desk, grabbing the case by the cover, but forgetting that I hadn't completely screwed on the cover. The bottom part of the case and the objective went flying their separate ways. I have developed an instinct to stick my foot under falling objects, and I managed to deflect the objective horizontally just before it hit the floor so it hit the hard unfinished stony cement floor at a reasonable angle (though with quite a high velocity). It still provides acceptable imagery but I suspect it has lost some of its excellence.

My heavy Panasonic S1R also fell from that desk onto the cement floor. It suffered no damage, not even a dent. I think it dented the floor.

[Chris S.]

. . . something serious happened to that lens to put those dents in those places, and not just once. I'd stay away from it.

Remember this lens? It looked every bit as distressed on the front outer ring, in addition to having chips in the glass.

Some would be fine with the optical performance, especially at a good price. Others would not.

--Chris S.

[Lou Jost]

Thing is, we'd never know. Except for your kind willingness to test them! If that is not an option, I think this is playing roulette with bad odds.

[Chris S.]

Thing is, we'd never know. Except for your kind willingness to test them! If that is not an option, I think this is playing roulette with bad odds.

Lou, I strongly agree that buying without testing is a gamble with bad odds. Offline, Dennis and I are looking into the possibility of my testing this objective.

--Chris S.

[Macrero]

We (and I include myselff) want perfect, flawless, tested, high-end optics for a fraction of their actual price. Yes, often it is too good to be true and there is a risk involved. Want a perfect optics? Go to Edmund and pony up. If you want a steal, you must take the risk. Period.

That seller, who I think is a forum member, did not respond to a message I sent him on eBay a year or so ago. He is already on my "blacklist". I just skip his listings, no matter how good the price is. First respect and education, then business...

[dhmiller]

Funny, as he answered my first query very quickly, then was very late on my second with an apology for his lateness, then everything else, including my request for a sample image using the objective, went unanswered... that wasn't very nice. But with a 2 week return period, I think I can get the lens tested and make the call on whether to keep it or not without much risk.

We (and I include myselff) want perfect, flawless, tested, high-end optics for a fraction of their actual price. Yes, often it is too good to be true and there is a risk involved. Want a perfect optics? Go to Edmund and pony up. If you want a steal, you must take the risk. Period.

That seller, who I think is a forum member, did not respond to a message I sent him on eBay a year or so ago. He is already on my "blacklist". I just skip his listings, no matter how good the price is. First respect and education, then business...

[mawyatt]

Dennis,

The Mitutoyo 20X listed on eBay doesn't look exactly like the one I have. The lettering is different is some ways. Maybe an older or newer model, or possibly a counterfeit

Anyway, with the warning from Macrero and the lack of response from your request, please proceed with caution.

Best,

[dhmiller]

Thanks, Mike. Yes I was told it was an older model - the seller did confirm that. Your warning has been heeded!

Dennis,

The Mitutoyo 20X listed on eBay doesn't look exactly like the one I have. The lettering is different is some ways. Maybe an older or newer model, or possibly a counterfeit

Anyway, with the warning from Macrero and the lack of response from your request, please proceed with caution.

Best,