How to open a Mitty?
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How to open a Mitty?
Hello everybody,
Does anybody know how to open a clamped Mitty, is there any special tool?
Thank you in advance.
BR, ADi
Does anybody know how to open a clamped Mitty, is there any special tool?
Thank you in advance.
BR, ADi
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Hi Macro_Cosmos,
I only want to open it but a cheap spanner wrench is not strong enough for that
https://www.ebay.com/itm/Pro-spanner-wr ... SwbKdcCiGC
So, probably I’ll have to assemble a solid tool by myself :-)
BR, ADi
I only want to open it but a cheap spanner wrench is not strong enough for that
https://www.ebay.com/itm/Pro-spanner-wr ... SwbKdcCiGC
So, probably I’ll have to assemble a solid tool by myself :-)
BR, ADi
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Hi Macro_Cosmos,
Many thanks for the hint!
So, I have just found that: https://www.youtube.com/watch?v=J16EeaibdNE
I haven’t tried to open the front of the lens up to now. So, maybe it won't be needed to open the clamped rear :-)
BR, ADi
Many thanks for the hint!
So, I have just found that: https://www.youtube.com/watch?v=J16EeaibdNE
I haven’t tried to open the front of the lens up to now. So, maybe it won't be needed to open the clamped rear :-)
BR, ADi
- rjlittlefield
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Adi, I'm curious: why do you want to open a Mitty?
If it's just to see what's inside, for curiosity, then great.
But otherwise, when Macro_Cosmos writes that "Generally disassembly is discouraged", what he really means is that you will almost certainly render the lens useless. In order to deliver their normally excellent image, the optical elements have to be aligned with micron-level accuracy. That's why even jarring a Mitty very hard will mess up its performance. In the video you found at https://www.youtube.com/watch?v=J16EeaibdNE , a good lens would have become trash at the moment the fellow unscrewed the black collar that was holding the front lens element in place.
--Rik
If it's just to see what's inside, for curiosity, then great.
But otherwise, when Macro_Cosmos writes that "Generally disassembly is discouraged", what he really means is that you will almost certainly render the lens useless. In order to deliver their normally excellent image, the optical elements have to be aligned with micron-level accuracy. That's why even jarring a Mitty very hard will mess up its performance. In the video you found at https://www.youtube.com/watch?v=J16EeaibdNE , a good lens would have become trash at the moment the fellow unscrewed the black collar that was holding the front lens element in place.
--Rik
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You likely will need a spanner wrench. It's a really good asset to anyone who's interested in opening stuff. If you don't mind spending a bit on something that works, I recommend this.
https://www.thorlabs.com/thorproduct.cf ... ber=SPW801
Do swap the heads around, the tip seems to snap easily. The back are slotted. I personally use a pair of spanner wrenches.
Thorlabs spw801 for slotted rings such as retainers and a generic ebay one for adaptors that have coupled holes for tightening.
Also, a calipers can be used as a spanner wrench, which is better in many cases.
https://www.thorlabs.com/thorproduct.cf ... ber=SPW801
Do swap the heads around, the tip seems to snap easily. The back are slotted. I personally use a pair of spanner wrenches.
Thorlabs spw801 for slotted rings such as retainers and a generic ebay one for adaptors that have coupled holes for tightening.
Also, a calipers can be used as a spanner wrench, which is better in many cases.
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You should be able to twist the front barrel off. I've tried to do that with zero success. I'm guessing heat will work as I suspect the application of threadlocker, but I'm not going to ruin my lens.Adalbert wrote:Hello Macro_Cosmos,
Unfortunately my spanner wrench is not strong enough for thy clamped screw of my lens.
Therefore I would like to try to open the front of the lens.
BR, ADi
I'm still wondering. Why do you want to open it?
Hello Macro_Cosmos,
I can unscrew the silver cylinder without any problem but have a big problem with the black ring.
- I want to see the construction inside of the objective
- It is a 2x lens, which I’m not really interested in
- It was really cheap
- I want to check if I can disassemble and assemble this lens and then I can use it
Concerning the last point I cannot imagine that the quality of Mitty is so bad that it cannot be assembled in the right way.
There is no possibility to align the groups, so I only have to screw the black ring to the original position.
BR, ADi
I can unscrew the silver cylinder without any problem but have a big problem with the black ring.
the are many reasons:I'm still wondering. Why do you want to open it?
- I want to see the construction inside of the objective
- It is a 2x lens, which I’m not really interested in
- It was really cheap
- I want to check if I can disassemble and assemble this lens and then I can use it
Concerning the last point I cannot imagine that the quality of Mitty is so bad that it cannot be assembled in the right way.
There is no possibility to align the groups, so I only have to screw the black ring to the original position.
BR, ADi
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I see, fair enough.Adalbert wrote:Hello Macro_Cosmos,
I can unscrew the silver cylinder without any problem but have a big problem with the black ring.
the are many reasons:I'm still wondering. Why do you want to open it?
- I want to see the construction inside of the objective
- It is a 2x lens, which I’m not really interested in
- It was really cheap
- I want to check if I can disassemble and assemble this lens and then I can use it
Concerning the last point I cannot imagine that the quality of Mitty is so bad that it cannot be assembled in the right way.
There is no possibility to align the groups, so I only have to screw the black ring to the original position.
BR, ADi
Mits have good image quality, but the construction isn't its strong point. I'd like to go on about their practices but someone else might not like my opinions. I'll keep it to that.
You can do something interesting though, take some photos with the lens before opening it. Then take photos with the lens after disassembling and reassembling.
The objectives are very easy to take apart and reassemble. I visited a friend, he has a broken 50x NIR which I played with. Remove the barrel, then the black shroud thingy holding the front element. The rest comes apart in a similar manner. It comes apart and back together in like 5 minutes. Since you don't care about your 2x, maybe try using heat.
- rjlittlefield
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Acceptable tolerances for a 2X should be a lot larger than for higher magnifications, so you might get away with disassembly/reassembly. It will be interesting to see. As Macro_Cosmos says, do take before/after photos with the lens, preferably in exactly the same setup as if you were doing a side-by-side test of two different lenses.
When you are disassembling the lens, I suggest to mark the side of each unit so that you can get everything lined up the same way they started. I don't know how Mitutoyo assembles their objectives, but I can certainly imagine that at some point they pick an orientation for one or more groups so that they play best with the others.
When you start to take the lens apart, see if there are some little holes on the side of the inner barrel, that have been filled with plastic. If there are, then probably those were used for final alignment, reaching through to push one lens group into its best place. I would take presence of such holes to be a strong sign that reassembly might be hit-or-miss.
--Rik
When you are disassembling the lens, I suggest to mark the side of each unit so that you can get everything lined up the same way they started. I don't know how Mitutoyo assembles their objectives, but I can certainly imagine that at some point they pick an orientation for one or more groups so that they play best with the others.
When you start to take the lens apart, see if there are some little holes on the side of the inner barrel, that have been filled with plastic. If there are, then probably those were used for final alignment, reaching through to push one lens group into its best place. I would take presence of such holes to be a strong sign that reassembly might be hit-or-miss.
--Rik
Hello everybody,
So, there is no possibility to align anything.
The cylinders of the optical-groups match perfectly to the tube of the body.
The front-group of my Mitty 2x looks like follows:
I haven’t found any possibility to destroy the lens if it has been opened from the front-side.
Only the middle group could be put in the opposite direction,
but it has a screw thread inside of the cylinder (only to the rear side).
So, I’ll have to take some test-photographs with this lens :-)
BR, ADi
So, there is no possibility to align anything.
The cylinders of the optical-groups match perfectly to the tube of the body.
The front-group of my Mitty 2x looks like follows:
I haven’t found any possibility to destroy the lens if it has been opened from the front-side.
Only the middle group could be put in the opposite direction,
but it has a screw thread inside of the cylinder (only to the rear side).
So, I’ll have to take some test-photographs with this lens :-)
BR, ADi