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BMFin

8mm fisheye fogging up

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I recently bought the Samyang 8mm f/3.5, which seems to perform very well exept for the super annoying fogging I had with it.

So far I have done two jumps with the lens on different days and on both jumps the lens started to fog perhaps 5 seconds after I climb out. I thought it might help to cool down the lens to get it adjusted on the lower temperatures at the altitude so on the second jump I held the lens in front of the fan nozzle of the aircraft for at least 3 minutes. This didnt seem to help at all.

Would be really helpfull if someone has experience on this issue with fiseye lens optics. Im not quite sure where exatcly does the fogging take place. Im suspecting it could be developing on the inner side of the front element. (this is just a guess)

Im also curious to find out why exactly some other lenses suffer from this problem and some others dont. My 10-22mm for example hasnt had this problem at all. Im guessing the problem might be that in the fisheye optics the front element is so thick. (just a hunch) However Im not very convinced this is the whole truth, since the difference on the thickness of the two front elements isnt that overwhelming..(see the pics attached)

I appologize if this has been discussed before. I only found discussions concerning videocamera WA adapters. Im more interested on how people have overcome this problem with SLR lenses. (especially someone with peleng 8mm or similar)

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I owned a canon 15mm fisheye and a sigma 15mm fisheye the canon did the same thing but the sigma worked fine. I traded of the canon. I believe the canon glass was thicker or something as well .


A friend will bail you out of jail , a REAL friend will be sitting next to you in the cell slapping your hand saying "DUDE THAT WAS AWSUM " ................

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Im still kind of puzzled about what exactly creates the fog.

Lets think about eyeglasses for example: When you step inside a warm enviroment (inside a house) coming from a cold enviroment, your eyeglasses will get foggy. But this doesnt happen usually when the temperature change is vice versa ? (from a warm house to cold outside)

In our case the situation is from warm to cold isnt it ? Why do we still get the fog ? Can anyone explain this to me ?

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In our case it is cold to warm and humidity.
It's cold at altitude and then gets warm and humid at opening altitude.
Notice when you land on the ground on a humid day if you lay your helmet down on the ground even for a second it will fog up the lenses immediately. Get it off the ground asap and it is just fine then. Moisture from the ground or warm ground causes it.


A friend will bail you out of jail , a REAL friend will be sitting next to you in the cell slapping your hand saying "DUDE THAT WAS AWSUM " ................

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Yes, but in my case the fogging started to arise already 5 seconds after I clibmed out and even before the exit. At this point the temperature was at the lowest. It was a nice warm summer day on the ground, but much colder at 13k (as it always is)

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I recently bought the Samyang 8mm f/3.5, which seems to perform very well exept for the super annoying fogging I had with it.



Is it possible to put on a flat filter in front of the lens or does it protrude out too far? If so, can you devise a clever way to put it on? I don't know the exact physics of it, but it worked for me a long time ago when I had fogging problems on my Hi-8.

4DBill
http://www.facebook.com/4dbill

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I don't have a solution for you... but I'll just say that my 10-22 does fog on occasion. And when it happens, it's usually internal to the lens... not something I can just wipe off. But I've only had it happen at cloud level, not exit altitude. The fogging was a real surprise on the 10-22... never happened so bad on my 18-55. I once had to hold the lens out the door of the plane during the climb to clear the fog from the previous jump. Worked great actually. Not that I recommend holding a lens (off the camera) out the door of a plane. But who knows, maybe you could keep your lens cold by holding it out the door for part of the ride up. Fog might clear by the time you exit.

Dave

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I once had to hold the lens out the door of the plane during the climb to clear the fog from the previous jump. Worked great actually. Not that I recommend holding a lens (off the camera) out the door of a plane. But who knows, maybe you could keep your lens cold by holding it out the door for part of the ride up. Fog might clear by the time you exit.

Dave



Yeah, I was also thinking the same thing. I will try and see how it works.

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I have always had a great deal of luck letting the lens on the body sit facing the sun, seems to allow for any moisture between the lens to be naturelly cooked off by the sun (it must evaporate I guess).

Let us know what has or has not worked for you when all is said and done!

Thanks, Arvel

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maybe you could keep your lens cold by holding it out the door for part of the ride up.



I have had quite the opposite experience. I find that when I keep my lens warm, it is less likely to fog on descent through warmer air. Warm air holds more moisture than cold air, and when air cools, it releases that moisture. That is why moisture often condenses on the already cold lens as it descends through warmer and warmer air.

Think about a cold beer bottle taken out of the fridge on a hot day. The warm moist air cools when it reaches the cool bottle, and the moisture condenses on the cold surface of the bottle (the same way moist air, when it rises and cools, releases it's moisture in the form of rain I believe).

I find if I can keep my lens warm, sometimes by positioning my helmet so the lens is in my crotch or hands, helps to reduces condensation.

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I've had problems with my Peleng 8mm on days of cold, humidity and heat. In fact on days like this, with lots of clouds and an extremely tropical climate, I do not know how to handle this situation. :(
I'll follow some of the advice posted here
I try to avoid jumping with peleng.
When this happened, I cleaned the internal humidity by placing the lens in a closed box with a lot of silica, for a week and it was great. Look at the photo for example.:D
Now in the summer in Portugal and Spain where I jump, I've got no problems with the Peleng, because the weather does not vary much with different altitudes.
blue skies

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I used to have the same Samyang 8mm... I had to sell it, it was fogging on every jump in the exact manner you have experienced.

I now use a Tokina 10-17mm, which doesn't fog.

I think it is something to do with the extremely thick front element you need in a lens like the 8mm Samyang. I don't know of anyone that has successfully used that lens to jump with, but if you find a solution, I would love to know about it!

Tom

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Its good to know you had the same problem with this.. On the other hand this could mean that the samyang is pretty much useless in freefall and I need to sell this lens.

I guess I will try a few more jumps and see how it goes. I would love to be able to shoot with this, since I prefer the samyang projection image to the peleng.

However if the next few jumps are the same, I will just trade it to a peleng. At least the peleng has been proven to work in freefall. (though it sure wont be trouble free either) I wonder if anyone has jumped the Sigma 8mm ?

Thanks for the help so far everyone.

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That sucks. I was about to order the samyang 14mm. It has even bigger front element…

Until I read your post I thought that the larger front element was not the cause, like pilotdave says. How many jumps (weekends) have you used the samyang 8mm? I read somewhere here that Laszlo was using the samyang 8mm, too. Not sure if he had the fog issue.

I had similar fog issues with raynox HD 3030 0.3x (video) and sigma 15mm before. But that only happened on a few occasions. I used century 0.3, which has a huge front element for almost 3 summers and I never had the fog issue.

Was the fog inside the lens?

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I have had no problem with the canon 15mm, tokina 10-17mm, Peleng 8mm or Zenitar 16mm except in 'extreme' weather conditions. I'm fairly sure that Willy Boeykens jumps the sigma 8mm on occasion so that must be a good lens.

Its a shame if the Samyang 14mm is similarly affected as it gets a good review here (in terms of resolution at least) http://www.photozone.de/canon_eos_ff/532-samyang14f28eosff
http://www.garywainwright.co.uk

Instagram gary_wainwright_uk

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UDPATE:

Today I did a funjump at a foreign DZ from 1000ft. I was jumping as a second camera man for a tandem just to test this lens. It was a nice warm and dry summer day. Lens seemed to work very nice this time. (see sample picture IMG_2049 taken with the 8mm) While there was some sunshine, earlier on the day, I kept the lens in a hot car without the lens caps so the lens would be totally dry. Im not sure if this had a real impact on anything, but at least this time the lens didnt fog.

However after I threw my PC, I had a really nasty case of line twists. As soon as I notice Im in trouble, at the same time I also notice how risers have opened the locking tab on my chincup and my helmet drops off my head. As a reflex I catch the helmet on my lap with both hands as Im already spiraling on my back parallel with the canopy towards the ground. With the camera helmet now on my hands Im strugling with the idea of weather to loose my helmet and cut away or spend a few more seconds to try to save my helmet. I decided to spend a few more seconds and I was thinking of holdint the helmet on my other hand and cutting away with the other. Somehow I felt it is too difficult to open the reserve with the right hand so I opted to wear the helmet back in my head again. I didnt manage to properly fasten my chin cup before I decided I better cut away before its too late. I cut away and my helmet flies off my head. (it could even be the risers crabbed it, who knows) I threw on my belly and open my reserve. The only thing going on my mind. "*uck where is the helmet, where is the helmet" and at the same time I see my helmet spinning towards the earth. I see the helmet hitting a pine tree in the woods and as I crab my toggles and prepare to flare I try to memorize where exactly it landed.

After 30 minutes I find the helmet on the woods pretty much undamaged. The still camera was twisted to the side and theres some pine needles,grass and dirt around the camera. At the time there also seemd to be a dent on the front glass of the lens, but when I got home it turned out it was only pine resin which I managed to wash away totally. The lens actually looks so new, I could sell it in mint condition right now if I wanted.

All in all everything seems to work perfect on my camera setup. I remember a while back there was this incident reported in the news : http://www.crunchgear.com/2009/12/15/canon-rebel-xt-survives-3000-foot-drop/ I guess im not the first one, but I do consider my self pretty lucky.

I wasnt as lucky with the freebag and the handles though, but I guess this is part of the sport.

1st jump at this particular DZ, 1st reserve ride, 1st dropped camera helmet ... etc.. BEER !!

For the sake of less weight on my head I didnt wear a video camera on my head which is a shame. It would have made one hell of a video to see me holding the helmet and filming my self as Im trying to figure out my next move.

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UDPATE:

Today I did a funjump at a foreign DZ from 1000ft.



I would suggest videoing your tandems from a much higher altitude than this... longer videos, less creative editing, less money spent on CYPRES cutters and all around more safe... I'm just sayin'... :P

P.S. Congratulations... YOU WERE LUCKY it turned out the way it did... losing ones helmet in freefall ends up resulting in much worse circumstances...

Gary "Superfletch" Fletcher
D-26145; USPA Coach, IAD/I, AFF/I
Videographer/Photographer

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I have a filter on my Tokina 10 - 17mm too ;)

However... then you're limited to about 12.5mm before you get the filter in shot!



Oh, yeah. I forgot that there is the zoom fisheye by tokina.

But like you said yourself, you cant utilize the full FOV with this lens either when you use a filter. You just cant get 180 degrees field of view without curvature on the front element.

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