Dry-Box humidity control mechanism (way more detail than we need to know)

Nov 17, 2020,17:11 PM

[Note: Machine translation from Japanese]

For example, inside the dehumidifying unit, a desiccant for absorbing moisture is provided. This desiccant is responsible for lowering the humidity inside the dry-box, but it cannot continue to absorb the humidity forever. Therefore, when the desiccant exceeds the limit of moisture absorption and the humidity inside the box exceeds the set value, a signal is sent to a heating body called a positive star to become hot. The hygroscopic power of the desiccant is restored, and the shape memory alloy coil made so that the total length changes when heated becomes longer. As the shape memory alloy coil stretches, the length of the bias spring that works with the exhaust / intake shutter changes. The exhaust / intake shutter opens and closes, and the air inside the box is discharged to the outside.

Conceptual diagram of the mechanism of the dehumidifying unit [above]. When the hygroscopicity of the desiccant in the center decreases, the orange-colored positive star (heater) becomes hot. Then, the shape of the red spring (heat extension type shape memory alloy) changes. The valve opens and steam is exhausted to the outside of the dry-box.

After a certain period of time (about 40 minutes), the shape of the shape memory alloy returned to its original shape, the exhaust shutter closed, and moisture absorption started. Although it is a surprisingly simple mechanism, it is characterized by its simplified structure and the use of highly reliable parts. The basic structure of the dehumidifying unit is [utilized by Toyo Living dry-box].

However, since last year, Toyo Living has incorporated a photocatalyst into the dehumidifying unit of the "Auto Clean Dry" series. In general, photocatalysts are known to generate a strong oxidizing action when exposed to light and promote the decomposition of harmful substances and the like. Titanium oxide is a well-known catalyst.

Titanium oxide is also used for auto clean dry, and LEDs are used as the light source. The effect is, "It can kill harmful substances in the air. I think it provides a higher level of security." ... "Leave it in the image sensor of a digital SLR camera. And dust such as gas adheres, but it can be prevented by a photocatalyst".

Since the moisture-proof cabinet is highly airtight, there is basically no air flow except when inhaling or exhausting. Unless air is applied to the catalyst, the effect of the photocatalyst should not appear. However, due to the convection effect of the heat of the Bojisutā [ボジスター], the air inside the dry-box circulates slowly, so there seems to be no problem.

By the way, the moisture-proof unit always operates with a household power supply. The electricity bill you care about is "about 30 to 50 yen a month". It's cheaper than a drink and shouldn't be a big problem in terms of running costs. By the way, the more the humidity changes, the more electricity is required, so the more frequently the camera and lens are taken in and out, the higher the maintenance cost will be.

Durability is also high. The fact that some models have a warranty period of 5 years shows that. During the interview, he showed me a dehumidifying unit that has been used for about 20 years. I was asked to do maintenance because it is broken, but when I checked it, it worked normally. It wasn't the dehumidifying unit that was broken, but the hygrometer. In addition, although the moisture-proof cabinet is always installed in a standby state, it is almost silent and no shaking is felt.

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My home work space...

 By: cshimokita : November 16th, 2020-00:08
When I moved into my new space some years ago I knew that I wanted a large work space so I special ordered this table (2,350 x 650mm). The equipment shown (left to right): 116 L electronic dry-box, Epson GT-X830 flat bed scanner for medium format film & p...  

Office and also hobby room?

 By: Weems@8 : November 16th, 2020-02:46
No need to shame using a watch winder, i use it also to keep the mainspring on strength. Mostly i pull out the crown to keep the mainspring on strength. Advice of a friend gave me who is a watch addicted persona. Advised me to get Omega Speedmaster. Despi...  


 By: cshimokita : November 16th, 2020-04:17
at the moment my daily wear is an automatic Seiko export only model that has been imported back into Japan by a brick & mortar retailer... that particular watch doesn't hack so it continues to run even with the crown pulled out ; ) Casey

Thanks Casey for sharing a part of your daily world — the desk looks great!

 By: orahu : November 16th, 2020-04:16
My wife and I bought a new condo earlier this year and we moved into it just as the pandemic lockdowns were becoming normative. I have yet to set up a home office, per se, aside from a simple computer work space. But, I am looking forward to it. No new ca... 

It was great fun prepping the space...

 By: cshimokita : November 16th, 2020-05:48
In my case I somehow knew that if I deferred any decision it would never get done ; ) As far as future considerations, I am thinking about a 50mm solution for use with the Canon dSLR... the EF24-70mm II has some appeal... it's a reported improvement on t... 

The work space can never be too big!

 By: fernando : November 16th, 2020-05:16
The same is true for closet space when it comes to the ladies.

I appreciate a good work bench... and a working reference library close at hand...

 By: cshimokita : November 16th, 2020-05:57
I do have a closet space issue ; )... only thing better than good tools is a nice jacket... I have too many including an anorak that I picked up when living in Alberta, Canada some 45 years ago... it still fits - hehehe... Casey

Hi, e-dryer?

 By: Jurry : November 16th, 2020-05:31
I never knew such a device existed but do I understand correctly it’s a kind of storage box which doesn’t cool like a refrigerator but keeps the air inside dry? I guess you can set the desired moisture level? If so, could you please PM me some more info a... 

How about sharing it with all of us Please?

 By: cazalea : November 16th, 2020-06:16
After a frightening episode with mildew and mold last spring (due to cracks in the wall), we did lots of sealing, cleaning, scrubbing, swearing, and finally have resorted to a de-humidifier. We run it every evening after we go to bed and the electric rate...  

Mike... it seems that 60% RM is the critical point regarding mold...

 By: cshimokita : November 16th, 2020-07:11
I've done my share of removing mold from older lenses... using a specific mix of ammonia and alcohol... they say it ever completely goes away. Also keep all leather etc. away from the camera gear. Mold is a nightmare... Casey

Yes, we had to clean every book in our living room

 By: cazalea : November 16th, 2020-09:17
Actually my wife did most as I was recovering from sinus surgery and the doc was adamant about me not getting spores, etc. and cleaning all the shoes, belts, etc etc. This past year was the wettest in about 25 years so that probably aggravated the humidit...  

The brand of electronic dry boxes that I have are from "Toyo Living"

 By: cshimokita : November 16th, 2020-06:59
the box is plugged into house power and it runs a small device that removes moisture from the air. There is also a blue light that runs continuously. Too dry is just as bad a too moist... target for camera equipment is about 35% RH (relative humidity). Li... 

Jurry... Good gear choices ; )

 By: cshimokita : November 16th, 2020-07:04
When the Z5/6 were introduced I successfully tested the FTZ converter with some older manual focus AI-s lenses... in aperture mode... The 24-70 has some appeal ; ) Be sure and let us know what you think of the gear... Casey

Honestly, who cares?!

 By: clifybyro : November 16th, 2020-11:25
How self absorbed can you get. Daily wear in the winder?! How about fucking wearing the thing! FFS! What is the world coming to.

hahaha... too funny...

 By: cshimokita : November 16th, 2020-13:22

Neat space

 By: Quan : November 16th, 2020-22:12
this make you feel comfort spending time on "hobbies"

The scanner on the left

 By: Quan : November 17th, 2020-22:32
and the computer is vintage. Many projects is a good sign Casey

The GT-X830 and the more expensive GT-X980

 By: cshimokita : November 18th, 2020-13:26
are both currently available flatbed scanners, the 980 is the more powerful unit with better film holders. Both of the WinXP computers are ancient and out of support but are good for stand alone / off-line processing. Both computers are well over 10 years... 

My workspace

 By: Jurry : November 17th, 2020-08:23
Forgot to add. But this is my work station at home Very comfortable great views ...  

What a great work-space...

 By: cshimokita : November 17th, 2020-13:23
It would be a challenge for me to sit there and actually work ; ) The chair and reading lamp is a nice touch... Casey

Thank you for your friendly words

 By: Jurry : November 21st, 2020-03:03
I’ve been lucky to have such an office in pour house viewing the golf course. During lockdown, when I was 4 months stuck alone in the house, that study is where I spent most my time. Behind the pc either working, or processing photos, and in the evening r... 

I recently got rid of my small couch and started to use a rocking chair...

 By: cshimokita : November 21st, 2020-03:25
but I have my eye our for an inexpensive wooden chair, foot rest, side table, and reading lamp... ; ) Casey

Dry-Box humidity control mechanism (way more detail than we need to know)

 By: cshimokita : November 17th, 2020-17:11
[Note: Machine translation from Japanese] For example, inside the dehumidifying unit, a desiccant for absorbing moisture is provided. This desiccant is responsible for lowering the humidity inside the dry-box, but it cannot continue to absorb the humidity...