GoPro 2 fogging remedy?

[uwxplorer 4]

Just came back from a Manta dive in Mona, where I had my GoPro Hero2 mounted on top of my L&M housing, set to time-lapse (2s) mode.

None of the shots where any good, being blurred due to what I think may have been fogging. There was clear condensation visible inside the housing (lens side). I usually don't have this problem in cold water, but I guess ambient humidity plays a bigger role than I thought...

Any advice on how to avoid this in the future?

The good news is that my video (taken with the Sony CX550 in the L&M housing) came out great!

[hellhole 24]

Strip dessicAnt... Sold on eBay

[ChrigelKarrer 52]

The GoPro 2 is heating up a lot while recording video creating condesation inside.

I have no experience with the essicant bags/stripes (i don't even use them in my DSLR housing) but i use mine with the following steps:
1° load the camera with dry hands

2° load the camera in your hotel room with the A/C on and in drying mode
3° If you don't have A/C in your room or need to open the housing outside; fill it with air from a scuba tank
4° Don't leave the camera on the sun, wrap it in a white, fluffy towel or if waters is very cold in a bucket of water

5° Don't let the camera recording all your dive, try to record only short parts of scenes you really want

 

In humid Costa Rica i can record approx 20 minutes continously before fogging start, while when i split it in 5 minutes scenes

with some interval between i can record much more .

 

Chris

[peterbkk 110]

Small bag of silica gel inside the housing will solve the problem.

 

LeisurePro sell them: http://www.leisurepro.com/p-fntsgp/fantasea-silica-gel-packs-absorbs-moisture-prevents-condensation-inside-your-housing

[uwxplorer 4]

All good advice, thanks.

On a slightly different topic, my friend used his GoPro 3 during that dive, and the footage is very noisy. I was very surprised by the poor quality, which reminded me of my first underwater camera, a Bonica.

He was shooting in 1080p30 (and did not suffer from fogging). What I do not understand is that the first sequence shot at the beginning of the dive (already in night conditions) looked fine...

Any comment would be appreciated.

[peterbkk 110]

All good advice, thanks.

On a slightly different topic, my friend used his GoPro 3 during that dive, and the footage is very noisy. I was very surprised by the poor quality, which reminded me of my first underwater camera, a Bonica.

He was shooting in 1080p30 (and did not suffer from fogging). What I do not understand is that the first sequence shot at the beginning of the dive (already in night conditions) looked fine...

Any comment would be appreciated.

 

It would be almost impossible to be sure what caused the noisy footage as there are no user controls and no metadata recorded by the GoPro. Everything is happening inside its automatic adjustments.

 

However, the noise is almost certainly coming from "gain". The GoPro is not seeing enough light and it is trying to amplify the amount that it is receiving, causing gain. There is no way to tell the camera, "OK, this scene is dark, let it record as under-exposed". It just pushes the "gain" up, all by itself.

 

Why did it change from the beginning of the dive to later in the dive? Not sure. But, is there somewhat less light in the scene in the later clips? Less reflective subjects? Different angle of the video lights? Anything that would have caused the GoPro to think, "not enough light, boost the gain"?

 

Unfortunately the downside of these excellent small video cameras is that you have no control over them.

 

Regards

Peter

[CheungyDiver 53]

Hmmm bit late to the party. Gopro housing has a small volume so any splashes when you open the box after rinsing will quickly heat up next time you use the box. Capillary action will wick some moisture to the inside of the seal. Tiny amount. My solution....wait for it....toilet paper. Good old loo roll works. Single ply or use the luxurious double ply for extra softness and absorbency. All you need is a single sheet and fold it so it cover the bottom (yes its a pun) of the box (more pun?) The tissue need to be dry obviously and will surprisingly absorb the humid air when the Gopro heats up. Change the sheet each time you open. The best thing is the tissue is ubiquitous and you could wipe of splashes when you open the box. Simple and useful.

 

As for why noise appears and inconsistency I think Peter explain most of it. Lack of control and also we are dealing with a tiny sensor. Now the new version is even smaller. Sensor heats up and lack of space for processing and cooling all contribute to the problem. Go Pro is a POV camera so I would not expect it to be a main videocamera for important footage. Always do tests and in doubt use a videocam that offer better features.

 

Cheers
David

[peterbkk 110]

My solution....wait for it....toilet paper. Good old loo roll works. Single ply or use the luxurious double ply for extra softness and absorbency.

Cheers

David

 

Any brand recommendations?

 

The one downside of loo paper is you must make sure that it does not interfere with the o-ring.

 

Regards

Peter

[CheungyDiver 53]

The brand I use has a puppy dog as a logo. Soft, comforting and reassuringly absorbent.

 

Sure that is why it must be folded to fit. Practice Origami .....

Edited October 30, 2013 by CheungyDiver

[peterbkk 110]

 

Sure that is why it must be folded to fit. Practice Origami .....

 

Will you be running toilet paper origami classes in your shop anytime soon?

[CheungyDiver 53]

yes free lesson with every housing purchased and a complementary sheet of 2 ply loo paper...LOL

[briand123 3]

The GoPro heating up has nothing to do causing any fogging. In fact, it heating up during the dive will actually work against fogging by raising the air temp some inside the housing.

 

Fogging all comes about from the air inside the housing cooling to the point it where it hits its dew point temp. The more moisture in the air, the higher it's dew point temp. So, you want the driest air inside the housing possible with the lowest dew point. The key is the air is dry enough so the dew point is lower than the coldest water temp you will experience during the dive. Then you will have no fog.

 

The easiest way to do this is to load the camera in a cool and dry environment (i.e. in A/C )and not on the deck of the boat. If you must open it on the boat deck, you could try to put it in a clear bag to close it and blow some air from your second stage into the bag just before you close the housing. Scuba air is less than 10% humidity, so the dew point will be very low. Just be very careful not to blow any water that may be on the reg into the housing or bag.

 

-Brian

[peterbkk 110]

If you must open it on the boat deck, you could try to put it in a clear bag to close it and blow some air from your second stage into the bag just before you close the housing. Scuba air is less than 10% humidity, so the dew point will be very low. Just be very careful not to blow any water that may be on the reg into the housing or bag.

No offense, but I can't see any situation where it would be a good idea to blow air from a regulator into a bag containing an open camera housing. The possibility of blowing sea water into that open housing is going to outweigh any benefit of getting dry air into the housing. Even a "dry" regulator can have pockets of water in its nooks and crannies. Maybe if the dive boat / shop has one of those blower attachments but, even then, compressed air can do other damage, like pushing an o-ring out of its groove or pushing a sand grain down behind an o-ring. David's toilet paper or my silica gel sachets is going to be a much safer more reliable solution.

[CheungyDiver 53]

Toilet paper should be ranked as one of the top ten inventions by mankind.....well in my book at least Now we have another use for it.

 

Dew point temperature is clearly understood even for me but let me reiterate what I wrote. If the go-pro and casing was use the first time then yeah no problem. After rinse when one opens that housing tiny droplets will spew forth in all directions (note to myself to film a hi-speed video showing this occurrence) these will land in all surfaces with opposite electrical charges. These tiny water droplets will be "stuck" there until one dries it with a ...wait for it ...a tissue paper or evaporated. In most occasions this is closed again thus trapping the moisture in. Plus the o-ring or gasket has the tendency to "suck" water from the external side of the o-ring to the internal side of the o-ring by pressure differential. The very act of opening the housing will cause a slight vacuum on the internal volume. Trapped water however small on the o-ring will get 'sucked' inside. This will happen even if inside and outside is equal pressure as capillary action will also tend to "suck" water into tiny gaps.

 

A dry tissue paper or a sachet of silica gel could take care of the slightly moisture atmosphere once the go-pro is closed for use again. Aircon room is a good idea for drying the housing but when you go outside you have to let everything return to ambient temperature.

 

Cheers

David

[briand123 3]

No offense, but I can't see any situation where it would be a good idea to blow air from a regulator into a bag containing an open camera housing. The possibility of blowing sea water into that open housing is going to outweigh any benefit of getting dry air into the housing. Even a "dry" regulator can have pockets of water in its nooks and crannies. Maybe if the dive boat / shop has one of those blower attachments but, even then, compressed air can do other damage, like pushing an o-ring out of its groove or pushing a sand grain down behind an o-ring. David's toilet paper or my silica gel sachets is going to be a much safer more reliable solution.

I actually have used a cloth covered flex tip valve on a power inflator hose to carefully do this on several occasions out of need (had to risk opening the housing for some reason on a open boat.) Never used a 2nd state regulator directly to do this personally since I had the tip. This was on a large volume housing where no typical silica gel pack is going to help ( not a go pro.) Obviously I didn't blast full-flow 100psi air in unabated, and expect most handling underwater cameras would think about why that isn't a good idea. Maybe I should add a disclaimer here. lol

 

There is no beating letting A/C'd air fill the housing before you close it up if you know the dew point of that air is safely below the coldest temp you'll experience during the dive. It doesn't matter if you take it outside after you close it and it sweats like a ice cold bottle of beer would, as that is on the outside (though it can freak some people out if they don't understand that.) Even as the air temp inside the housing rises or falls with the ambient environment, the dew point remains constant inside the housing as long as it's not opened.

Edited November 7, 2013 by briand123

[SPP 16]

All good advice, thanks.

On a slightly different topic, my friend used his GoPro 3 during that dive, and the footage is very noisy. I was very surprised by the poor quality, which reminded me of my first underwater camera, a Bonica.

He was shooting in 1080p30 (and did not suffer from fogging). What I do not understand is that the first sequence shot at the beginning of the dive (already in night conditions) looked fine...

Any comment would be appreciated.

 

Hero 3 comes in 3 flavor. HD3 White ( improved HD1 engine ), HD3 Silver ( improved HD2 engine ) and HD3 Black, the true HD3.

For UW use HD3 Black, set Cam Raw Protune. Run the free GoPro Studio 2.0 which allows transcoding to Cineform 220 mbps the original MP4 Protune file.

Run the GP Studio 2.0 in parallel with other editor, say Vegas or whatever you use and many recognize Cineform codec.

 

Being recorded in Protune and when transcoded to AVI ( PC ) or MOV ( Mac ) however one mess with it, it is only the "active metadata" being mess with, Cineform file stay virgin forever and one can reset it back as many times as needed. Most color correction can be done and easy to be done in GoPro Studio 2.0 ( old one called Cineform Studio ). Fine tuning color one can do in their NLE of choice, while both programs running together.

 

Cineform Active Metada 101

https://cineform.zendesk.com/entries/23259777-What-is-Active-Metadata-

 

Cineform is robust and the soon VC-5 codec by SMPTE will be based on Cineform.

 

GoPro CamRaw MP4 is not true raw like photo file, but it is very good for UW use. Color recovery is easier and better than AVCHD 28mbps for distant objects. On land or water, Protune CamRaw makes color matching easier to other camera and specificly on land, one can bring out the shadow details much better.

 

There is no other micro camera with wide angle lens this cheap this good for video, for now.

Once you get hooked to CamRaw in Protune, and know how to recover the lost color, you will love it for a US$400 product ready to use and the free lighweight editor/color correction GP Studio 2.0 can deliver...for FREE.

 

Sun-ball or banding is not an issue when shot in Protune + CamRaw. Noise is very low, as long as choose MEDIUM or WIDE and not NARROW FOV.

2.7K WIDE ( 2714 x 1524 ) is one of the best recording resolution to use for HD3 Black, you can render to 1080p as-is or crop and get pure 1080 x 1920 while removing the edges distortion WIDE FOV usually give from a flat lens housing UW. 1080p MEDIUM is not bad to use too, if one does not wish to go too wide.

 

Make sure card is not Sandisk, it is now capped to 35mbps when using Sandisk, even Sandisk Extreme new one or the older Extreme Pro, if firmware is latest V03.3 on HD3 Black.

 

Use approved card and one will get the 46mbps MP4 Protune with latest HD3 Black firmware, or use 1 firmware number lower.

 

NOTE :

Protune on HD2 or HD3 Silver ( both 35mbps ) is not as powerful or has the fidelity as Protune in HD3 Black at 46 mbps.

Protune is a capture format, not a delivery one.

 

Attached some test sample I did.

Hope this help.

 

 

Have fun......

[SPP 16]

The GoPro heating up has nothing to do causing any fogging. In fact, it heating up during the dive will actually work against fogging by raising the air temp some inside the housing.

 

Fogging all comes about from the air inside the housing cooling to the point it where it hits its dew point temp. The more moisture in the air, the higher it's dew point temp. So, you want the driest air inside the housing possible with the lowest dew point. The key is the air is dry enough so the dew point is lower than the coldest water temp you will experience during the dive. Then you will have no fog.

 

The easiest way to do this is to load the camera in a cool and dry environment (i.e. in A/C )and not on the deck of the boat. If you must open it on the boat deck, you could try to put it in a clear bag to close it and blow some air from your second stage into the bag just before you close the housing. Scuba air is less than 10% humidity, so the dew point will be very low. Just be very careful not to blow any water that may be on the reg into the housing or bag.

 

-Brian

 

 

Camera heating up is also one of the reason for fogging, because temperature difference is what trigger the dew point.

Water moisture in gas form in air aka humidity has a limit to how much air can hold that water in gas phase, before it has to give it out in liquid form which is the fogging we know or rain in extreme case of high water moisture storage. Hotter air can hold more water moisture. Per 1 cubic meter of air at 30C at 100% RH can hold as much as 30.4 grams of water or 30.4 cc of fresh water or 600 drops, eye drop size in gas form. In contrast, a 20C ambient air at 100% RH can only hold 17.3 cc of water or grams in gas form. This is the simple reason if in Bali your car air-cond is very cool at 24C average and you wear Sunglass and sitting in front where the air cond vent is powerful, open the door when arrived in Tulamben......woosh, foggy glass you get the moment you step out of your car in mid hot sun.....within 5 seconds. The hot humid air which touches the cool sunglass can not avoid releasing its gas form water moisture to become liquid/fog......that is gas law, no way around it. Do any LOB on a good vessel with 23C cool non-stop air cond running for our rooms. Place a DSLR in the room for 3 hours, run to stern of the LOB vessel with that camera to take picture of friends loading the zodiac, foggy lens guaranteed.

 

In the topics at 90% humidity at 30C ambient, all one need to do is get in the water which is 2 degrees cooler and when the lens of the housing has come to the same temperature of the water, even without hot air generated from camera operation in the housing, the dew point is already reached for the air near the housing lens innner side for plastic housing. Aluminum housing is better in this case as the port lens is never faster to be cooled by surrounding water as the alu housing material. So housing lens fogging is hard to occur on alu housing. Polycarbonate vs glass, glass gets cooler faster and more so for thin 1.xx mm GoPro housing lens, compared to 2.5mm polycarbonate housing material the GoPro uses.

 

It is all about temperature difference and how wet the air is to begin with.

When camera in operation and air in housing gets hot, even the humidity is the same as the minute the camera was placed in the housing, the temperature spread gets higher and it will be easier/faster to trigger the fogging.

 

Use dewpoint calculator to see, it is easy.

http://www.decatur.de/javascript/dew/

 

Enter 30C ambient. 90% RH +-1

You will get 28.18C as "fogging temperature".

 

For plastic housing so small like GoPro, what I do is simple.

Get a 1-2 liter clear see-thru plastic bag.

Place GoPro and housing opened up, in the plastic bag.

Flatten plastic bag to remove all wet ambient air.

Inject dry air from scuba tank into plastic bag till plastic bag expand like baloon. Tie with rubber band.

Allow 5 minutes to generate expedited drying of moisture attached to seal of housing and all components of the camera.

Dump air out a bit, close camera housing while still in plastic bag.

DONE - One just place the driest air available for scuba divers in camera housing, beating any air cond air which at best is 40% RH in the tropics.

 

Scuba tank air, if dive operator is anal on quality and more so when they have Bauer Securus sensor, that is a minimum of -55C dew point or well under 1% RH ( -55C DP Temp = 0.05% RH actually ) or equal to European EN12021 breathing air standard. -55C dew point temperature is filter life expired limit under EN12021.

 

However, there are many places in Asia where air standard is so poor, expect 10 to 20% RH and some drops of water in scuba tank...ha ha ha.

 

David is right, even metal hold water moisture, let alone flexible seal on camera housing.

If ones operate a NIST certified/traceable -80C dewpoint sensor, one will be amazed that copper tube is a "wet" metal.

Plastic is VERY WET. Seals are WET WET WET.

 

Desscicant and dry scuba tank air is a potent combination for reliable non fogging on micro sized camera housing like a GoPro with minimalist air-space.

Dessicant is cure, scuba tank dry air is preventive.

 

HD3 Black under highest data bit recording in Protune 46mbps, will have temperature rise of 25C or starting at 30C and be 55C in just 13 minutes in open air without a housing, imagine when one uses the housing. GoPro HD3 or even HD2 is a "hot" camera, but it does not overheat as fast as Sony NEX7 in 1080p 50fps.

 

 

Attached is a test of HD3 Black, 1080p 60fps Protune 46mbs for 30 minutes.

All in Celcius, taken with a FLIR/EXTECH i5 thermal camera.

65.5C is the lens metal perimeter which is also the heat radiator of the CMOS sensor.

HD3 Black when using Protune is crazy hot and is more prone to fogging than any other GoPro lower grade version.

 

In desperate condition where I do not have time or the plastic bag, I spray scuba tank air to housing with camera inside it, 2cm open door and close it. Not the best but not too bad. I then use two of GoPro HD3 Black and use them alternatively, let one cool.

The more often one use the GoPro camera, the heat it generated will dry some part of the camera itself, it will be less fogging prone than a virgin brand new camera, given that the storage is in the housing and the housing remain closed while in storage and been exposed to dry scuba tank air often.

 

 

The fogging test, attached. Done on GoPro HD1 some years ago.

TEST 1 - Ambient air 30C ( see smaller digit on temperature meter ). Cool water to 10C ( larger digit ) with ice. Close camera housing with ambient wet air of at least 80% RH, typical tropical country. Fogging blind within 4 minutes camera recording.

 

TEST 2 - Use scuba tank air to inject and dry camera+housing, minimum -55C DP dryness of air but total water moisture removal is perhaps only as good as Zero Celcius dewpoint at best, but more than enough. 12 minutes camera recording no issue. Even 2 hours recording is not an issue as fresh water coldest temp is never below zero Celcius or no more than -2C for salt water of typical 35,000PPM salt.

 

Have fun guys....n safe diving.

[CheungyDiver 53]

hey SPP

 

Great explanation it is like going back to school. Interesting stuff.

 

I shall bring a few bin bags with me in my next trip. If the centre could give me some spare nitrogen then even better.

 

 

What thermal imaging camera did you used?

 

thanks for sharing that

 

cheers

 

David

[SPP 16]

Hi David,

 

Mine is a Extech i5 by Flir. Its a low cost 80 x 80 pixel resolution

http://www.tequipment.net/Extechi5.html

Used to be US$2K but now its lower

 

I suggest you buy this one :

http://www.tequipment.net/FLIRE6.html

This is a 160 x 120 pixel, better resolution but price still within US$2.5K.

 

FLIR practically owned the thermal imaging world.

 

See resolution difference

http://www.flir.com/thermography/americas/ca/view/?id=61647&collectionid=845&col=61648

 

Since u got so much expensive camera toys, troubleshooting using thermal camera is better than those spot measurement using the other type of infra red thermo gun, which the laser guide dot and the sensor reading area is not that accurate/aligned anyway.

 

The higher resolution model you choose, you can shoot 1 image from a bit further away and get more data than lower resolution one at same distance.

It will come handy for all cameras asset you got or when you tinker with them.

 

 

Have fun shopping David.

 

[uwxplorer 4]

Terrific lecture David, thanks.

There must be a large fudge factor though, as my buddy dove with a H3 BE and was shooting 1080p30 w/o Protune (with my H2, I was shooting a continuous 5M pixels time-lapse series at 2 s intervals, and except for the graininess, I don't think he suffered from fogging.

We both set up or cameras in the same apartment in Kona.

I was surprised, because I had never experienced this in SoCal, but even though the temperature difference from surface to bottom can be as large as 20° F, I guessed what saved me was the lower humidity.

I also wanted to mention that I put my gear in the rinse bucket > 1 hr before the dive, as told...

[Davide DB 583]

Many thanks for your post

[uwxplorer 4]

Bought the GoPro dessicant tablets after trying the toilet paper trick: too much risk to pinch TP with the housing and flood the unit. Those tablets fit perfectly. I just need to go back to some hot and humid destination...