Accuracy of hygrometer in dry box/cabi vs usefulness


pstiang

New Member
Jan 19, 2010
105
0
0
#1
I have a digital cabi, with digital RH setting. What i found out was:

I set my cabi to RH 45%. When the cabi shows that it reached 45%, my another xtra analog hygrometer which is inside show RH 55%
I changed the analog hygrometer position to another tray in my cabi, and it will stay at RH 65& for the rest of the time.

This experiment shows that the RH in cabi is not fixed throughout? And it clearly shows digital and analog hygrometers are not 100% accurate.

The problem is this, most of us know that a dry box/cabi is best to keep at 40-50% for our cameras n lenses, but, how many of us know that the hygrometer of ur box/cabi is accurate? For those whose box/cabi is actually higher than RH50%, and their hygrometer is showing 45%, think that their camera and lenses are safe from fungus?

At this point of time, I am sure many of us bought what is call "something to protect our equipment", but actually its not protecting it.

Solution? Get a accurate hygrometer. Cost some more $$. But, will anyone do it?
Anyone has a cheaper method to check if the hygrometer on the box/cabi is accurate?
 

tunge

New Member
Mar 15, 2009
502
0
0
38
#3
i have a 38L AIPO dry cabinet (2 tier) so i bought 2 digital hygrometer for each tier in addition to the original meter on the dry cabinet. i set 40% RH for my cabinet and my 2 external digital hygro indicates RH 45-46% so overall i'm pretty pleased with the performance
 

spheredome

New Member
Jul 5, 2007
1,199
0
0
AMK
#4
You have a possible choice. One is to lower till 35% using the build in meter, so if the backup hydrometer is the one giving the correct reading, then you will still have 50%, still not too bad as compared to 65%-75%

So the choice is yours, leave with potential fungus or leave with unfounded theories of dried oil, cracking plastic/rubber and PVC circit board.

...This experiment shows that the RH in cabi is not fixed throughout? And it clearly shows digital and analog hygrometers are not 100% accurate.

The problem is this, most of us know that a dry box/cabi is best to keep at 40-50% for our cameras n lenses, but, how many of us know that the hygrometer of ur box/cabi is accurate? For those whose box/cabi is actually higher than RH50%, and their hygrometer is showing 45%, think that their camera and lenses are safe from fungus?

At this point of time, I am sure many of us bought what is call "something to protect our equipment", but actually its not protecting it.

Solution? Get a accurate hygrometer. Cost some more $$. But, will anyone do it?
Anyone has a cheaper method to check if the hygrometer on the box/cabi is accurate?
 

izerkudie

New Member
Jan 1, 2010
254
0
0
#5
just throw and put in millions of silica gel will do ;)
 

pstiang

New Member
Jan 19, 2010
105
0
0
#6
I think best is have hygrometer calibrated. do "salt test" with an extra analog/digital hygrometer and compare with the one in ur box/cabi. This way, you can confirm that your dry cabi/box is protecting your equipment.
 

Taurean

Senior Member
Sep 8, 2005
1,705
0
36
White Elephants Town
#7
Got a digital Hydrometer recently, while my analog meter reading is at 45%, the digital reading will be at 31-34% :confused:

Did a "salt test" last night, both meters reading are quite close to 75%.

Now I don't know which meter to trust. :confused:

Any body encounter this before?
 

Barrios

Senior Member
May 19, 2002
715
0
16
57
Visit site
#8
Got a digital Hydrometer recently, while my analog meter reading is at 45%, the digital reading will be at 31-34% :confused:

Did a "salt test" last night, both meters reading are quite close to 75%.

Now I don't know which meter to trust. :confused:

Any body encounter this before?

For how long did you do your 'salt test'? It has to be done for 24 - 36 hours.
 

giantcanopy

Senior Member
Feb 11, 2007
6,232
2
0
SG
#9
Actually i just trust whatever reading the meter gives me.

The only time i got abit more uptight was when the meter went blank
( changed battery and hey presto .. )

but interesting read nevertheless.

ryan
 

Barrios

Senior Member
May 19, 2002
715
0
16
57
Visit site
#11
If that is the case, then one of your hygrometers is probably not accurate at that RH range.
The Caliber III digital hygrometer, for example, claims to have an accuracy of +/- 1% at RH range of 40%-80% and +/- 3% outside that RH range. :)
 

Jun 16, 2009
148
0
0
#12
i might be wrong, but my cabinet was advertised as +- 10% RH. I prefer leaving it hovering around 30 to 35% to offset the error margin
 

FireZ

Deregistered
Sep 21, 2008
1,230
0
0
#13
Hi peeps...did a search but can't find an answer (perhaps my search was wrong?)
anyway..my question is... on average..how long it takes the dry cabinet to reach 45% RH upon open up?

jus bought my digi-cabi 30L.. i set it up at 7.30pm..but till now..it is still hoverng at 53% RH..i set it to maximum also...
btw...the current time is 9.28pm..which mean..i haf turned on for about 2 hrs plus..

kindly guide..

thanks!
 

Hsq7575

New Member
Jun 30, 2008
24
0
0
#14
I think best is have hygrometer calibrated. do "salt test" with an extra analog/digital hygrometer and compare with the one in ur box/cabi. This way, you can confirm that your dry cabi/box is protecting your equipment.
Hi, just thinking how do we know which hygrometer is giving the correct reading? :dunno:
 

Top Bottom