Wet Lens - advice on fighting fog (cold water dives)

[rhwestfall]

Dive this weekend that the video rig is going, and it will be deep. Right now water at the surface is in the mid 60's (air will be almost 90), and below the thermo will be 40's. The video rig I am using is using the Ikelite WA lens (so it is a "wet" connection). As it takes a bunch of time for the space to fill through the little relief holes, and I somewhat doubt being able to attach it once in the water, any suggestions of dealing with (1) getting the air out, and (2) fogging when the thermocline comes into play?

 

[asha]

Why do you doubt your ability to detach/reattach it in the water?

I occasionally experience air bubbles between my camera port and wet lens, and a detach/reattach underwater fixes it in a few seconds. I don't recall ever having issue with fogging, though.

 

[rhwestfall]

clumbsy with cold water gloves (and unlucky) .....

I was considering soaking it to get the bubble out, but the concern was that it would be 70+ (likely 80) water, so once it is in there, and it hits 42 under the line.....

 

[Interceptor121]

Is this a W-20 with 67mm thread?

 

[rhwestfall]

Is this a W-20 with 67mm thread?

yes it is

 

[ScubaSteve]

I never had a problem with my W20 lens fogging because I made a routine of unthreading the lens "at depth" quickly to get water into space in between. Along with this, I assemble my camera in a very cold/dry area (right next to an air conditioner) to capture cold/dry air in the camera housing and reduce the likelihood of fogging. I do not have a 100% success rate but I've only lost a couple dive due to fogged camera.

 

[rhwestfall]

(right next to an air conditioner)

man, I need to dive with you......

 

[asha]

Fogging=condensation. Condensation requires an air space. You shouldn't have an issue with fogging so long as there isn't an airspace between your lens port and wet lens, which is solvable by attaching the lens underwater. Agreed that the threading is a PITA, but short of switching to a bayonet mount system, you don't really have a choice in the matter.

Fogging inside the camera housing is a different matter entirely.

 

[rhwestfall]

gotcha! Thanks.