Blurred lens

Techniques and equipment.

Moderator: Moderators

Blurred lens

Postby stefan » Dec 26, 2009 1:01 pm

Hello,

I have a problem that sometimes is really anoing. Sometimes the lens get blured because of temperature differences and it takes a lot of time for them to clear up. Especially if you use the camera in winter, as the temperture inside the cave is greater than the outside temperature.

The only way I managed to deal with this problems was to wait for the camera temperature to increase and for the blur to simply go away. Cleaning the lens didn't help at all...

Did any of you had this kind of problem? How do you solve it ?

Thanks
stefan
Infrequent Poster
 
Posts: 18
Joined: May 22, 2007 5:04 pm
Location: Timisoara, Romania
Name: Stefan M.
  

Re: Blurred lens

Postby Chads93GT » Dec 26, 2009 1:11 pm

I have it every time I go caving. My solution...............Open up the case and let it "air out" and adjust to the new temp. You are never going to not have the problem when the camera is one extreme temp, and it goes into an environment of another extreme temp. Same reason everyone's glasses fog up in the winter when they come in from the outside.

I carry Q tips to speed up the condensation removal process from my camera.
User avatar
Chads93GT
NSS Hall Of Fame Poster
 
Posts: 2294
Joined: Jun 24, 2008 1:27 pm
Location: Missouri
  

Re: Blurred lens

Postby Phil Winkler » Dec 26, 2009 2:02 pm

It is not only the fogging that causes blurring problems, but the expansion and contraction of the different lens at different rates (due to thickness variations) causes differences in focal lengths between the lenses. Hence the blurring. Allowing cameras to adjust to the different temperatures is the answer as provided above.
Phil Winkler
13627 FE
User avatar
Phil Winkler
Global Moderator
 
Posts: 2375
Joined: Sep 5, 2005 8:48 am
Location: Wilmington, DE and Dewey Beach
NSS #: 13627FE
  

Re: Blurred lens

Postby Jeff Bartlett » Dec 29, 2009 2:09 am

Fogging on the lens is caused by the moisture in your breath (and the cave air, and the steam coming off of your body) condensing onto the cold lens. Ever take your camera out on a hot/humid day, after a trip in a cold cave? The same thing happens.

One solution is to put a heat packet inside the camera case, right up against the lens. While it won't get particularly hot -- those things need air to work -- it'll keep the lens warmer than the ambient cave temperature, preventing fogging. Just a few weekends ago, I took a series of cave photos in a very wet cave, where I was sitting in waist-deep water for a few of the shots. Everyone was steamy, and lens condensation is a constant impediment to photography here. This trick completely prevented my lens from fogging up, and the photo trip was a success!
"Although it pains me to say it, in this case Jeff is right. Plan accordingly." --Andy Armstrong
User avatar
Jeff Bartlett
NSS Hall Of Fame Poster
 
Posts: 948
Joined: Jun 29, 2007 12:19 am
Location: Chattanooga, TN
Name: Jeff Bartlett
NSS #: 59325
Primary Grotto Affiliation: Tennessee Cave Survey
  

Re: Blurred lens

Postby wyandottecaver » Jan 1, 2010 1:42 pm

The heat pack trick does work wonders
I'm not scared of the dark, it's the things IN the dark that make me nervous. :)
User avatar
wyandottecaver
NSS Hall Of Fame Poster
 
Posts: 2902
Joined: Aug 24, 2007 8:44 pm
Location: Indiana
  

Re: Blurred lens

Postby Chads93GT » Jan 1, 2010 4:31 pm

I learned yesterday that you have to opent he heat pack a while before putting it into the case, as it needs oxygen to activate. I simply opened it up and threw it in. It never got hot, lol. Tomorrow I will try yet again.
User avatar
Chads93GT
NSS Hall Of Fame Poster
 
Posts: 2294
Joined: Jun 24, 2008 1:27 pm
Location: Missouri
  

Re: Blurred lens

Postby wyandottecaver » Jan 1, 2010 8:41 pm

you can also buy sealed ones that dont need oxygen.......
I'm not scared of the dark, it's the things IN the dark that make me nervous. :)
User avatar
wyandottecaver
NSS Hall Of Fame Poster
 
Posts: 2902
Joined: Aug 24, 2007 8:44 pm
Location: Indiana
  

Re: Blurred lens

Postby Chads93GT » Jan 1, 2010 8:46 pm

Brand? (where to get?)

the ones i got have to be exposed for 15-30 minutes and shook up before they get hot. I made the mistake of simply opening it and putting it in the case immediately.
User avatar
Chads93GT
NSS Hall Of Fame Poster
 
Posts: 2294
Joined: Jun 24, 2008 1:27 pm
Location: Missouri
  

Re: Blurred lens

Postby wyandottecaver » Jan 1, 2010 9:28 pm

mine are lost deep in my gear pile but they are essentially plastic pouches with a metal disc imbedded in a gel. You boil them to turn the gel to liquid then when you flex the disk inside the reaction turns them hot and they gradually get hard as the reaction goes on. You boil them again to re-use.

one site is here

http://www.9thtee.com/reheater.htm
I'm not scared of the dark, it's the things IN the dark that make me nervous. :)
User avatar
wyandottecaver
NSS Hall Of Fame Poster
 
Posts: 2902
Joined: Aug 24, 2007 8:44 pm
Location: Indiana
  

Re: Blurred lens

Postby captnemo » Jan 1, 2010 10:14 pm

wyandottecaver wrote:mine are lost deep in my gear pile but they are essentially plastic pouches with a metal disc imbedded in a gel. You boil them to turn the gel to liquid then when you flex the disk inside the reaction turns them hot and they gradually get hard as the reaction goes on. You boil them again to re-use.

one site is here

http://www.9thtee.com/reheater.htm


Funny you should mention those- I was just going to order some for keeping warm on longer motorcycle rides, fromhttp://www.hotsnapz.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=H&Category_Code=HCP a friend got some from them and were happy with them. I've used similar packs before and like the fact that they're reusable. They get pretty warm though so don't know if I'd put them in my camera bag.
User avatar
captnemo
Prolific Poster
 
Posts: 128
Joined: Jul 10, 2009 12:46 pm
Location: California
NSS #: 44985
Primary Grotto Affiliation: mother lode grotto
  

Re: Blurred lens

Postby NZcaver » Jan 1, 2010 11:31 pm

Somewhere I have a few of those liquid heat packs with the metal disc inside. I haven't used them in years. Mine are fairly large like the ones in the links, which I think makes them a little bulky/heavy for caving and hiking etc. I couldn't fit them in my camera cases with all my gear packed in there. I guess smaller ones would be OK though. Do they make any miniature versions?
User avatar
NZcaver
Global Moderator
 
Posts: 6342
Joined: Sep 7, 2005 2:05 am
Location: Anchorage, Alaska
Name: Jansen
NSS #: 50665RL
  

Re: Blurred lens

Postby Jeff Bartlett » Jan 4, 2010 3:26 pm

captnemo wrote:They get pretty warm though so don't know if I'd put them in my camera bag.

Yeah, I'd only recommend doing this if you have a waterproof/airtight case like a Pelican. This prevents them from having enough oxygen to really get cooking too good.
"Although it pains me to say it, in this case Jeff is right. Plan accordingly." --Andy Armstrong
User avatar
Jeff Bartlett
NSS Hall Of Fame Poster
 
Posts: 948
Joined: Jun 29, 2007 12:19 am
Location: Chattanooga, TN
Name: Jeff Bartlett
NSS #: 59325
Primary Grotto Affiliation: Tennessee Cave Survey
  

Re: Blurred lens

Postby stefan » Jan 4, 2010 4:58 pm

Thanks guys for all your help. I'll have to try the heat pack trick. :grin:
stefan
Infrequent Poster
 
Posts: 18
Joined: May 22, 2007 5:04 pm
Location: Timisoara, Romania
Name: Stefan M.
  

Re: Blurred lens

Postby BrianC » Jan 4, 2010 5:52 pm

I have some dust behind my lens and some scratches that cause a slight burr off center in my pictures. I accidentally submerged the lens once that allowed the dust to collect behind the lens!
User avatar
BrianC
NSS Hall Of Fame Poster
 
Posts: 2061
Joined: Oct 2, 2006 2:34 pm
Location: up on this here mountain
  

Re: Blurred lens

Postby NZcaver » Jan 4, 2010 6:05 pm

Jeff Bartlett wrote:
captnemo wrote:They get pretty warm though so don't know if I'd put them in my camera bag.

Yeah, I'd only recommend doing this if you have a waterproof/airtight case like a Pelican. This prevents them from having enough oxygen to really get cooking too good.

FYI - the heat packs in Capt Nemo's post don't require oxygen to activate or 'get hotter.' They're a sealed pouch containing gel and a clicky disc, which uses a different chemical reaction to the old tea-bag style hand warmers.
User avatar
NZcaver
Global Moderator
 
Posts: 6342
Joined: Sep 7, 2005 2:05 am
Location: Anchorage, Alaska
Name: Jansen
NSS #: 50665RL
  

Next

Return to Photography and Videography Forum

Who is online

Users browsing this forum: No registered users