Within less than 1-year, I have had to send my 16X zoom lens back to CanonUSA in Irvine, CA for "cleaning of optical path". At first, I thought that by obtaining some selica gel packs, I could arrest this development of mold in my Canon lens. It seems that this lens is more prone to growing mold than other lenses I own. Whazzup?

I've been told by some pros here in the Philippines where I now live that I should not store my lens in darkness...which I've been doing, even with selica gel inside a vinyl bag and rubber banded shut.

Is exposing lenses to warmth of the sun going to inhibit the growth of fungii and mold?

Anyone with tropical experience (with long stays in this kind of environment) please share your experience with me and others who do shoot in hot/humid environments like the Philippines or plan to do so in the future.

Thanks.

Collis

I spent some time in the Philippines after the revolution. Mold, mildew and fungus is just a part of life in tropical environments. I've never found the silica packs to be too beneficial for optical equipment that is used daily. If the lenses are used daily I don't think a short stay in a dry environment is long enough. Silica probably works fine for long term storage.

I tried to limit the time my equipment was in A/C. The changes in humidity and resultant condensation seemed to promote the growth of the fungus. Dark conditions are also known to promote its growth. Exposure to daylight (UV) will inhibit or slow the growth.

My experience with lenses that have developed a fungus problem is that it never really goes away. It may be next to impossible to remove all the spores, I just don't know. I would sell the fungus prone lens and try to keep the new one dryer and stored in light conditions.

Eventually the fungus eats (etches a path) into the multi coating of the lens. When that happens the only remedy is to replace the element. Big expense for a lens that is likely to develop the problem again.

Collis,

Unfortunatley, we in the warm and wet climates have some nasty issues to deal with when it comes to equipment.

If your equipment is not totaly dry before you put it in that banded shut, vinyl bag, with silica gel, then you are probably setting yourself up for a science experiment.

Those silly little silica packs that come with the original equipment are fine as the gear is packed under nominal conditions. They are not made to remove real moisture in a hostile environment, only absorb what little may have been introduced in the packing process. To help combat the adverse effects of moisture and heat you need larger, heavier duty packs.

I agree with Jeff's assesment that once you have the problem, it will probably very difficult, if not impossible to erradicate completely.

All of our gear is kept in an airconditioned environment which is cool and dry. Realistically, most of our work takes place in hot and humid environments. This is just the nature of the beast.

We do have our "On Call" packages that are kept in secure vehicles, so temperature changes are not an issue.

If you know you are going to need a specific piece of gear, it would behoove you to acclimate it slowly to the operating temperature you need. This will help in cutting down interior moisture caused by condensation.

Also, if you use air/water tight cases like Pelicans, make absolutely sure that your gear is completely dry before storage. The same wonderful features of these cases that keep air and moisture out, also keep air and moisture IN. Another award winning, biological experiment.

Good luck and keep it dry.

RB

Jeff and Rick...

Thank you for your helpful comments.

I do use the "heavy duty" selica gel packs, not the ones that come with newly purchased gear.

I think you both pretty much nailed down what goes wrong when moving from a frigid into an oven-like outdoor environment in the tropics with perhaps pre-existing moisture beginning to condense, then setting the stage for a growth. I probably have been remiss in aclimating gear sufficiently before opening up sealed stuff to warm air.

Gel packs I use are of the indicator type, i.e., they turn blue when saturated (although I've never seen them reach that level since I bought here in a moviemakers supply shop in Manila).

Canon USA has been distressingly mum on the whole matter, which is even more disturbing to me. Other kinds of fungii or mold others have reported which form on metal parts have not been observed with my gear.

Interestingly, I haven't encountered this problem with camera lenses, both 35mm and medium format 6 X 4.5 cm equipment. Curious!!

Collis