Re: Lens condensation question

"Floyd Davidson" <floyd@xxxxxxxxxx> wrote in message
news:87k6czu7fs.fld@xxxxxxxxxxxxx
> "Skip M" <shadowcatcher@xxxxxxx> wrote:
>>
>>Nope, didn't say that. It just works in reverse, going from hot and dry
>>to
>>cold and wet. Happened to me on Saturday, going from cool, damp outside
>>to
>>the relatively warmer and drier interior of a venue.
>
> It never works in reverse. It is *always* the cooling of air to a
> temperature below the dew point. The dew point changes, of course,
> depending on the temperature and the relative humidity.
>
>>But what I was referring to was in SoCal, if it is truly hot, it is
>>probably
>>a Santa Ana, which can produce relative humidity in the singe digits, and
>>if
>>it is damp, it is winter, and relatively cold.
>
> In fact it can happen at *any* temperature and relative humidity
> combination. The point in every case is that if the air touching
> the camera is rapidly dropped to a temperature below the dew point,
> it *will* result in condensation.
>
> Air with single digit relative humidity is not immune, it just
> has a lower dew point.
>

Well, it sure happened to me, going from the rain to the inside of the
reception hall, my lens, and viewfinder, fogged up. Logic told me that it
couldn't happen, but it did. Probably because, even though the lens was
already damp, the lower temp of it condensed what moisture was in the inside
air. I guess.

--
Skip Middleton
http://www.shadowcatcherimagery.com


.

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