Moisture condensation in stereomicroscope

Everything relating to microscopy hardware: Objectives, eyepieces, lamps and more.
Post Reply
Message
Author
User avatar
ivangallego24
Posts: 33
Joined: Thu Nov 15, 2018 11:20 am
Location: España

Moisture condensation in stereomicroscope

#1 Post by ivangallego24 » Fri Nov 22, 2019 2:24 pm

Hello everyone, my problem is today I have seen that on top of the slide turret and where the prisms are where the eyepieces go but on the outside I have seen that there was some condensed moisture, which was removed with toilet paper and a stick , and I have covered it again with the plastic, but in a little while I have seen that there was condensed moisture in those parts of the stereomicroscope again, and in my room the strangest thing is that there is no other object that condenses moisture, and I think that It only happens to be covered, any solution to this problem?
And the humidity outside the stereomicroscope is very bad?

Scarodactyl
Posts: 539
Joined: Sat Mar 03, 2018 9:09 pm

Re: Moisture condensation in stereomicroscope

#2 Post by Scarodactyl » Fri Nov 22, 2019 3:08 pm

Microscopes need to be kept in temperature and humidity controlled environments. Presumably there are temperature swings making it condense moisture, which is obviously not great.

Hobbyst46
Posts: 2306
Joined: Mon Aug 21, 2017 9:02 pm

Re: Moisture condensation in stereomicroscope

#3 Post by Hobbyst46 » Fri Nov 22, 2019 4:52 pm

ivangallego24 wrote:
Fri Nov 22, 2019 2:24 pm
Hello everyone, my problem is today I have seen that on top of the slide turret and where the prisms are where the eyepieces go but on the outside I have seen that there was some condensed moisture, which was removed with toilet paper and a stick , and I have covered it again with the plastic, but in a little while I have seen that there was condensed moisture in those parts of the stereomicroscope again, and in my room the strangest thing is that there is no other object that condenses moisture, and I think that It only happens to be covered, any solution to this problem?
And the humidity outside the stereomicroscope is very bad?
Water vapor in air tends to condense on relatively cold surfaces (relatively - by comparison with the surroundings).
What is the humidity in the room ? note that the correct term is relative humidity. Its units are percent. 10-20% is typical for deserts, 90-100% is typical for tropics in a rainy day. Along the sea shore it might reach 70% in the summer (not everywhere, it also depends on the winds and geography). Usually weather forecasts show the expected relative humidity.
There are inexpensive temperature/humidity desk displays that are not very accurate but enough for your purpose.
Until you find out what is the relative humidity near the microscope, I would cover it with a bag made of cloth (I prefer cotton) rather than plastic bag.
The two likely problems that condensation will cause are mold and corrosion.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

User avatar
ivangallego24
Posts: 33
Joined: Thu Nov 15, 2018 11:20 am
Location: España

Re: Moisture condensation in stereomicroscope

#4 Post by ivangallego24 » Fri Nov 22, 2019 6:20 pm

And if I dry the moisture fast will cause some damage equally?

Hobbyst46
Posts: 2306
Joined: Mon Aug 21, 2017 9:02 pm

Re: Moisture condensation in stereomicroscope

#5 Post by Hobbyst46 » Fri Nov 22, 2019 6:29 pm

ivangallego24 wrote:
Fri Nov 22, 2019 6:20 pm
And if I dry the moisture fast will cause some damage equally?
Sorry, I do not quite understand the question. The microscope should not be under condensation, never ever. There is no way to wipe the condensed water fast enough to prevent damage, if condensation happens again and again. If permissible, could you provide more details, what is the setup around the microscope that leads to such effects. Are there any cooled instruments attached to the microscope ? is the stage being cooled for any purpose ? are there vapor sources around ?
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

PeteM
Posts: 796
Joined: Tue Dec 06, 2016 6:22 am
Location: Santa Cruz, CA

Re: Moisture condensation in stereomicroscope

#6 Post by PeteM » Fri Nov 22, 2019 7:52 pm

As suggested above, moisture condenses on any temperature lower than the dew point. If you have high relative humidity, the temperature of your lens surface needs to be only a few degrees colder to have water vapor condense on it. Perhaps your microscope is stored in a room where it gets cold over night? Perhaps you live in an area of high relative humidity?

Biggest problem is that above 60% or so relative humidity you're more likely to get mold or fungus growing on your optics. The general recommendation is to keep relative humidity well below 55% or so. So you definitely want to take action. Possible approaches:

- Store the microscope in a humidity-controlled case when not in use. This could use something like silica gel and be tightly contained OR heated above the dew point using something like a small incandescent bulb in the case. I suppose you could also pull a vacuum :-). Then make sure the microscope is only taken out of the case when it is above the dew point. A cheap electronic humidity gage can be of help, though many provide only an approximate indication.

- Store and use the microscope in a humidity-controlled room. Easiest approach is a dehumidifier set to around 30-55% relative humidity and the doors closed so you're not dehumidifying the entire house.

User avatar
ivangallego24
Posts: 33
Joined: Thu Nov 15, 2018 11:20 am
Location: España

Re: Moisture condensation in stereomicroscope

#7 Post by ivangallego24 » Fri Nov 22, 2019 11:46 pm

This is the area where humidity appears every little while, the weirdest thing is humidity only appears in that particular area
IMG_20191123_003431.jpg
IMG_20191123_003431.jpg (111.37 KiB) Viewed 400 times

Chris Dee
Posts: 64
Joined: Mon Aug 12, 2019 1:02 pm

Re: Moisture condensation in stereomicroscope

#8 Post by Chris Dee » Sat Nov 23, 2019 10:42 am

Given the location shown I'd suggest its caused by the warmth/humidity of your own breath using the microscope. Insulating that area with some foam tape should prevent it.

Post Reply