| Author |
Message |
    
Gw265ster
Tinkerer
Username: Gw265ster
Post Number: 1
Registered: 03-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 01, 2009 - 04:43 am: | 
|
Yesterday my new 50mm lens arrived from some nice eBay person. Before I'd even had a chance to use it, it got doused very liberally with water*.
A couple of hours later I noticed a small amount of condensation inside the front elements of the lens. Overnight I put it in an airtight box with lots of slica gel, but the condensation has got worse, not better.
I do realise that for the price of repairs I could get another 5 CZJ 50mm lenses off eBay, but (1) does anyone know how I might repair this and (2) does anyone know of a reliable, good person who could repair my lens? I'm in Cambridge, UK, but would be prepared to send it overseas if this didn't turn put to be prohibitively expensive.
*A friend's toddler knocked a jug of water off the table onto what I only later realised was my camera case, holding the lens. Luckily nothing else was in the case... |
Donnie_strickland
Tinkerer
Username: Donnie_strickland
Post Number: 64
Registered: 09-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 01, 2009 - 06:50 am: |
|
As you have seen, putting it in an airtight box made the problem worse. You must allow the moisture to escape to the atmosphere. You could try putting the lens under a desk lamp or something similar; the heat will speed up the drying process considerably.
Of course it is still possible that even after it dries, there might be residue that requires cleaning, but I would try this approach first as it is simple and non-invasive (and free!). |
Glenn
Tinkerer
Username: Glenn
Post Number: 523
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 01, 2009 - 08:10 am: |
|
Putting it in an airtight box with plenty of silica gel can work, but only if there is enough to absorb 'All' the moisture, the silica gel has been dried out at 105 deg C immediately prior to sealing the box and, you are prepared to wait.
The results you saw are very common when a lens has been 'dunked', and starts to dry out. In general the water/liquid enters the interior as 'large' droplets, but as these start to evapourate during the drying out process, the interior fills up with water vapour which condenses all over the interior surfaces.
Depending on the item to be dried out, I would tend to place the box of silica gel in an airing cupboard or on a radiator shelf. One should be aware that application of heat to a damp object, can drive the moisture (water vapour) deeper into the interior before the drying cycle is completed. This is not normally a problem with mechanical/most electronic items; however, optical elements deeper in the interior may be left 'watermarked' as the moisture moves dust etc onto the lens surfaces. Thus the initial appearance of problems with a front element, can end up with all the interior lens surfaces being marked. |
Steve_s
Tinkerer
Username: Steve_s
Post Number: 153
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, March 01, 2009 - 01:58 pm: |
|
I would stick with the airtight box and silica gel (provided it is good and dry), but cycle its location between a warm place and the refrigerator every couple of hours to accelerate the interchange of air between the dry exterior and the damp interior within the front elements. The only way the moisture trapped inside will get out is by the thermal expansion of the air, and contraction drawing in dry air. As Glenn says, you may find the surface left watermarked, but the quicker you can get the water out, the better your chances of a usable result. |
|
