Lense Cleaning & Moisture

[PapaBear]

I hope this isnt repeating something elsewhere but I tried using the search of the forums and didnt find anything, needless to say apologies for both the noddy question and if I have got it wrong.

I picked up my housing Tuesday for my ixus 950 and am loving it. I followed the canon guide of testing it empty in the water to see if any leaks and has proven fine. However when I was running my finger around inside the case to feel for any moisture I think I have put a finger mark on the lense area the camera shoots through. I hadn't noticed it in any photos and tried wiping with a glasses cloth to no avail. Anyway I took it in the pool last night to see how it all came together and get a feel for the camera. The finger smudge has gone but I appear to have a few small rings as if something has dropped onto the lense on the inside I can not wipe clean. I think these rings are now visible in the photos but it could just be my first time shooting underwater (don't think it is really but just in case)
Is there any cleaning solution or wipes I can get/use to clean up the housing without damaging anything?
Also will putting satchets of silica gel you get in everything free help prevent condensation if taking the camera from hot to cold, for instance from the nice warm dive boat to the not so warm UK sea?

Thanks guys,
J

[DDT uk]

Does it look sort of like oil? Lenses are coated with a special solution. Rub the lens too hard or too often and you can remove it. What you may be able to see is not something on the lens but something not on the lens. If it is thing then I would doubt that you will see it on pictures other than in the form of sharpeness or refraction.

Daniel

[PapaBear]

Im not really sure, the most I can describe it as is a very small ring or bubble. It is not in the same area as the smudge which seems to have cleaned itself up now. I will try to post the picture I took with the bubble in to get a little expert advice.

[browng]

I used to experience condensation on my wide angle lens in my Olympus PT 015 housing when diving in the Maldives. Despite trying all sorts of things, my wife's hairdryer, warming up in the sunshine , allowing the dry air from the air conditioner to blow on it, etc but the best thing I found was coloured silica gel in little plastic tubes which I bought in the USA. I could trap them between the housing and camera and avoid them getting between the camera and the housing controls. But best of all they could be re-generated by warming them up and they changed colour showing that they were ready for use. They had to be stored in sealed bags.

Interestingly I have not experienced the same problem with condensation in my Subal housing - could it be it has more of a heat soak and therefore less likely to have condensation.

The other tip I heard about is to place a peice of aluminimum foil inside the hosuing and the condensation will occur on that first. I can't say that it was 100% successful.

Anyone with other thoughts?

[DDT uk]

I must say that I always use Silica gel bags in my [S&S] housing. Not the little ones either. Not only do they stop condensation but they will also soak up the water in the event of a small leak. As I understand it, they normally absorb a mass of water equal to their own. So the 10g bag will absorb a small spoonful and could prevent damage to the camera.

Daniel

[PapaBear]

Does anyone know where I can get some silica gel bags? Aside from the ones you get in something else to keep them fresh?

Thanks for all your help and advice guys,
J

[browng]

Have a look at Indicating Silica Gel Desiccant Bags

I have not used these before but they look a reasoanble price and they show when they have been all used up by turning green. I am going to buy some and see how they work.