Freezing Lens Problems

[WarBird Dude]

Folks,

I shoot with a DVC Pro camera and lately the cold has been affecting my lens in strange ways. Say if I'm standing outside for 10 minutes waiting for a live hit, my focus begins to get tight and my back focus gets out of whack. I have to jog the macro ring a few times

I reset the back focus and it's good for awhile then the process begins again when we go back outside for the next hit.

It's so bad, I can't keep my focus while following what the reporter is talking about.

Help! It's cold out here, and I can't see~!!

WarBird

[BluesDaddy]

Is it possible that the temperature shift from the truck to outdoors is making parts of the lens housing contract? Thus making the focus shift?

[<a-b-roll>]

I worked in minnesota for almost 6 years, I know what youre talking about. I'm pretty sure that the cold make the lubricant in youre lense solidify. When you zoom or focus the backfocus ring probly sticks one of those elements because the oil in the lense is has hardend. The only I've found that the only way i know to deal is to keep the camera from being cold for that long. Heating pad (electric or chemical) would work or leaving it in the truck as long as possible or move to a warmer climate like southern california.

[Terry E. Toller]

It is most likely the lubricant that is packed into the lens. There are special 'low temp' lubricants you can have your lens treated with.

WARNING! I worked with a photog who thought it would be a good idea to heat the lens with a tungsten light. WRONG! He screwed the lens up so bad it would zoom by itself and wouldn't stay in focus.

[A/B roll]

sweet, the veteran agrees. I feel so smart :)

[queen of blue]

Originally posted by Terry E. Toller:

WARNING! I worked with a photog who thought it would be a good idea to heat the lens with a tungsten light. WRONG! He screwed the lens up so bad it would zoom by itself and wouldn't stay in focus. Question - Would being in the trunk of your car during a heat wave cause the same problem? We have a Sony DSR 200A with an internal focus lens that does this sometimes. Not all the time mind you, just sometimes. Usually it does it when you attempt a slow zoom either way, then it will start to slowly and steadily zoom all the way in.

I apologize for the hijack - it just never occured to me that something like this might be the problem.

[Jaded]

The hand warmer packs you can buy for your gloves will help a little-- but YOU MUST WRAP THEM IN SOMETHING like a towel, or even a glove. Also it helps if you set the camera to the climate and leave it there if at all possible-- IE if youre going to be shooting live shots outside, try to get the camera outside at least 15 minutes before your shot so it has time to acclimate to the cold. Lots of tips out there for this kind of thing-- keep fishing.

[Terry E. Toller]

That's not a bad idea! I found some chemical warmers at ACE hardware. Two for a buck and they last several hours each.

As for being in the trunk, I have never had a problem with that. The guy I was writing about would turn a 1K lowel onto the lens for a minute. His lens had to be sent in to be repacked.

[queen of blue]

Originally posted by Terry E. Toller:
As for being in the trunk, I have never had a problem with that. The guy I was writing about would turn a 1K lowel onto the lens for a minute. His lens had to be sent in to be repacked. Good night! It's hot here .... but maybe not quite THAT hot.

I'll try the hand warmer thing too next time I need it. Man I wish I had thought of that myself about 8 years ago.

[Shootblue]

The weather sucked here two weeks ago...ass cold and high humidity. I had left the camera out overnight accidently (damn falling asleep). Needless to say, It took me nearly an hour to get the thing through the condensation cycle. I am pretty sure that the condensation was on every element of glass--I'd get one layer clear just to see it right behind that layer. Luckily the interviewee was understanding.