Hi all,
Received my used Mitty a few minutes ago, opened the package and noticed that the objective has a big circle of haze in between the elements. It's cold here and the objective barrel is cold but i don't believe this is normal unless some moisture got in between, am i wrong?
Thanks
Mitutoyo 10x 0.28 - damaged?
Moderators: rjlittlefield, ChrisR, Chris S., Pau
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DavidG1980
- Posts: 33
- Joined: Tue Jan 10, 2017 4:28 pm
- Location: Portland, OR
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DavidG1980
- Posts: 33
- Joined: Tue Jan 10, 2017 4:28 pm
- Location: Portland, OR
-
DavidG1980
- Posts: 33
- Joined: Tue Jan 10, 2017 4:28 pm
- Location: Portland, OR
-
DavidG1980
- Posts: 33
- Joined: Tue Jan 10, 2017 4:28 pm
- Location: Portland, OR
I definitely see it.
Something I don't know is how much this should worry you. If you can't get rid of the haze--say, by placing the lens in a bag of dry rice or other desiccant for 24 hours--then the lens should definitely be returned. But if you can get rid of the haze--as in "so well-rid that the haze does not return when the lens is cooled"--then it may be fine.
Let me explain my thinking. Some degree of lens breathing is probably a given if a lens changes temperature. If the lens is cold, and while warming, is exposed to reasonably humid air, it could easily suck some of this air in and fog up. As an avid skier who was long dependent on eyeglasses, I know all too well that instant fogging is the order of the day whenever cold optical surfaces are brought into a warm room.
For this reason, I've always had a firm habit of warming up cold lenses inside of plastic bags, so that room air doesn't touch the lens until it has equilibrated. Having this habit, I've never seen a camera or microscope lens internally fog. But this habit exists because I'm of the impression that such fogging can easily occur.
--Chris S.
Something I don't know is how much this should worry you. If you can't get rid of the haze--say, by placing the lens in a bag of dry rice or other desiccant for 24 hours--then the lens should definitely be returned. But if you can get rid of the haze--as in "so well-rid that the haze does not return when the lens is cooled"--then it may be fine.
Let me explain my thinking. Some degree of lens breathing is probably a given if a lens changes temperature. If the lens is cold, and while warming, is exposed to reasonably humid air, it could easily suck some of this air in and fog up. As an avid skier who was long dependent on eyeglasses, I know all too well that instant fogging is the order of the day whenever cold optical surfaces are brought into a warm room.
For this reason, I've always had a firm habit of warming up cold lenses inside of plastic bags, so that room air doesn't touch the lens until it has equilibrated. Having this habit, I've never seen a camera or microscope lens internally fog. But this habit exists because I'm of the impression that such fogging can easily occur.
--Chris S.
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DavidG1980
- Posts: 33
- Joined: Tue Jan 10, 2017 4:28 pm
- Location: Portland, OR
-
DavidG1980
- Posts: 33
- Joined: Tue Jan 10, 2017 4:28 pm
- Location: Portland, OR
Nope, i might be overreacting now because i love glass and i... care for it, even tho it's not mine 
Im just aware of why pro-grade microscopes are installed by proffesionals instead of being mailed. They know that average user expertise ends at how to turn focus knob, but user imagination goes way beyond that (we are scientists after all
)
Those are precise instruments,designed for specific use, and they are not weather sealed. If they did weather seal those (and sacrifice other traits for reasons i cannot imagine) and design it to work with 20W lamp, im pretty sure there would be someone who decide to try it with 200W HBO bulb and then wonder why he cannot get DIC with the lens anymore.
Only weather sealed objectives im aware of are water and oil immersion lenses, and it's only the first element.
Everytime he allows the lens to get that condensation, lens performance will deteriorate a bit as during drying there gonna be some crystalisation on the glass surface. Keep bringing it back and forth from your garage and you'll end with ground glass. This is also an invitation for fungi. You should put the lens in airtight container and do not remove it until the temperature stabilise.
One could say, "you just need to dissasemle it and clean the glass as there are few groups in premounted tubes". I guarantee you, that if you do that, you'll never restore it's original performance, their alignment is that critical for apo glass.
Im just aware of why pro-grade microscopes are installed by proffesionals instead of being mailed. They know that average user expertise ends at how to turn focus knob, but user imagination goes way beyond that (we are scientists after all
)Those are precise instruments,designed for specific use, and they are not weather sealed. If they did weather seal those (and sacrifice other traits for reasons i cannot imagine) and design it to work with 20W lamp, im pretty sure there would be someone who decide to try it with 200W HBO bulb and then wonder why he cannot get DIC with the lens anymore.
Only weather sealed objectives im aware of are water and oil immersion lenses, and it's only the first element.
Everytime he allows the lens to get that condensation, lens performance will deteriorate a bit as during drying there gonna be some crystalisation on the glass surface. Keep bringing it back and forth from your garage and you'll end with ground glass. This is also an invitation for fungi. You should put the lens in airtight container and do not remove it until the temperature stabilise.
One could say, "you just need to dissasemle it and clean the glass as there are few groups in premounted tubes". I guarantee you, that if you do that, you'll never restore it's original performance, their alignment is that critical for apo glass.