Condensation on Canon Binoculars (1 Viewer)

After much indecision I finally took the plunge and bought the 18 x 50 IS model. They arrived today.

I was initially very pleased with the quality, but whilst out bird watching today, I had problems with condensation on the inside of the front 50mm lens. After I put the binoculars down for 15 minutes the condensation evaporated.

I would have thought that Canon would assemble their binoculars in dry conditions.

Has anyone any advice?

What were the weather conditions?

If you go out into very cold weather (below freezing) you can expect some condensation, but if the weather was not that cold, then there is perhaps excessive humidity inside, and you might call up Canon about it. Granted, the binocular is not marketed as waterproof and is not nitrogen filled, but it should not fog up in normal conditions.

In very cold, especially cold and windy conditions, it helps to hold something heat-insulating such as your mittens or the sleeve of your coat over the objectives for the first five or so minutes when you are outside. This keeps the glass warm while the body cools down, and forces the humidity to condense on the insde of the body rather than on the glass.

Kimmo

It wasn't cold today. The outside temperature was 15c. I had been out for a couple of hours and the condensation gradually built up over that time. It only went away when I put the binoculars down and they cooled.

It seems strange that condensation will form on a warmed surface.

Condensation forms when an object cools below the dewpoint. The lens must have been cooler than the dewpoint of the air inside the binocular.

That's not what happened though. The condensation formed when the binoculars warmed up from the heat of my hands holding them. When I put the binoculars down and let them cool, the condensation disappeared.

Perhaps the moisture was originally on the inside of the body of the binoculars, and was evaporated when the body warmed up. The lens would have been cooler and therefore provided somewhere for the moisture to condense.

This definitely sounds like excessive moisture inside the binocular. I would contact Canon customer service about this. Non-waterproof binoculars can, of course, get moisture into them if you take them for a week of sailing or a camping trip in rain etc., but virtually straight out of the box what you describe should not happen.

Kimmo

I spoke to Canon Customer Service today. Because the binoculars are brand new, they gave me an authorisation code to get them replaced.

It took a month for my supplier to obtain these binoculars. I hope the replacement arrives a little sooner.