Housing Sentry Vacuum Seal

Since everyone recently has been talking about Vucuum seals for housing I thought I input on my recent experience with Housing Sentry from Underwater Camera Stuff (http://uwcamerastuff.com/housing_sentry_overview.htm)

I decided to go with the basic setup which has no electronics and uses the manual hand pump. I installed the valve in the Hydrophone port of my Aquatica AD7000 and it took me a couple of minutes to do.

Here are some pics of the layout:

The basic setup like mine retails for $290usd plus shipping.

Have used the setup for the past 3 weeks and think its one of the best things I have bought for my camera housing. Like alot of other I think that every brand of housing should have this setup as a standard part in each new housing.

I found that Bill and Mary from Underwater Camera Stuff great to order from especially for me here in Australia

Regards Mark

Got one from Bill to try for Diver Mag. I agree that it took seconds to fit and worked as intended. My only gripe is that there is no permanent monitoring (you have to refit the pump to check). However, if you have no factory-fitted option, this is still better than no test!

http://www.backscatter.com/sku/bs-ale.lasso

Backscatter has now come out with a new system with a LED indicator. In addition, you get to keep the moisture indicator if installed as a backup.

My insurance policy for my camera and housing is the same amount as this system.

The Meltdownman

I actually put my housing together and vacuum seal it the night before or hours before I am diving. Then I test to see if there is a vacuum just before I go out on the boat. If the seal is going to fail it will most likely be during this time. I dont see the point in an electronic part to keep monitoring the vacuum during the dive especially if it cost an extra $200.

Regards Mark

It's not for monitoring during the dive but it is very useful to glance at the indicator just before you commit yourself to the deep! (...and I sleep well in my cabin, with that little green light winking away!) Each to his own...Then again, if I flood my camera, I lose my camera, a lens and my job.

Another vote for the Housing Sentry and Bill at Underwater Camera Stuff. I have had my system since 2011 with no issues.

Guess I will take the extra 10 seconds to use the pump to check my seal and save the $200 cost of the little winking green light. On the other hand if my job was on the line due to failure of one Housing/Camera I would be packing an extra housing and camera body to be on the safe side.......that would make me sleep well

Regards Mark

http://www.backscatter.com/sku/bs-ale.lasso

 

Backscatter has now come out with a new system with a LED indicator. In addition, you get to keep the moisture indicator if installed as a backup.

 

My insurance policy for my camera and housing is the same amount as this system.

 

The Meltdownman

It is my understanding that the new backscatter option is a new purchase and you can't upgrade from there previous unit released a couple of months ago.

The cost of your insurance is a yearly fee. Will your insurance policy have any effect on weather your camera floods? It sometimes is not a matter of getting the gear replaced once you get back home and file a claim and pay the deductible but, rather a matter of keeping the camera from flooding while on a week long live aboard half way around the world.

Actually Bill,

I have your Housing Sentry and it's the cat's ass. Acutally on 2 of my 5D MII Aquatica Housings. It saved my butt on a predive check so it paid for itself. As usual I was in a hurry to go after trying to fix my strobes (which weren't firing) and the boat was about to leave. Classic set up for disaster.

I do have the added insurance policy to cover both the camera and housing should it get flooded, lost or stolen. I do like the idea of a keeping the moisture alarm in the event the pressure switch fails. With the moisture sensor still working along with the vacuum still in play during a dive is good backup. In addition, God only knows what the baggage handlers do to your housing even when packed in a Pelican case. I have a few scars on the case already that are worth noting.

The new unit out by Backscatter looks very appealing too but I have not seen any reviews on it yet. With regards to the light on it I don't have a opinion as to whether it is better to be external to the housing vs. internal for the Housing Sentry nor do I have an opinion for the seal on the Backscatter system and whether its disconnect is any better than the stainless steel from the Housing Sentry. So far the Housing sentry has held up on over 3 dozen dives at recreational depths.

One feedback on the Housing Sentry is that many people prefer to remove the hydrophone since they don't use it anyway (and complain that the cord gets in the way). The Housing Sentry uses a differenct port. I personally like the option of having a mic available but honestly have not used it yet. I will when I get into experimenting with video this year.

One thing not mentioned in any discussion that I have seen is that for those individuals that have masks with the colored filters on them will have any difficulty seeing the blinking green or red indicator lights for either vacuum indicator. I know that the green indicator light looses some of its color in the Housing Sentry when in the water. While I still can see it easily blinking underwater it definitely is not as green underwater. There is a concern that if I were to slowly lose vacuum and the color shifts to red that I might not be able to pick it up as readily. I don't know about the Backcatter light indicator and if it does the same thing with the same colors. Nor have I used a mask with a red filter on it and if that would disrupt seeing the change in indicator color should it shift from blinking green to blinking red if vacuum were to decay off due to a slow leak.

The last question is just how much vacuum should one pump the housing down to and whether or not it is actually good for the seals? I have not seen a figure on what vacuum is "enough". Surely some of the vacuum must be pulling somewhat on the rubber o rings and will drawing a vacuum cause them to unseat or distort over time with the added sea pressure acting in the same direction?

One final note on using a vacuum system it is nice to know that having a vacuum will help keep the housing closed in the event that a latch were to accidently come loose or not snapped into place at all before or during a dive. I did try to pull apart my housing with the latches not latched and the halves would definitely NOT come apart. However, I did draw a pretty high vacuum when doing this (15" Hg).

My two cents.

The Meltdownman

One feedback on the Housing Sentry is that many people prefer to remove the hydrophone since they don't use it anyway (and complain that the cord gets in the way). The Housing Sentry uses a differenct port. I personally like the option of having a mic available but honestly have not used it yet. I will when I get into experimenting with video this year.

Actually Bill,

 

I have your Housing Sentry and it's the cat's ass. Acutally on 2 of my 5D MII Aquatica Housings. It saved my butt on a predive check so it paid for itself. As usual I was in a hurry to go after trying to fix my strobes (which weren't firing) and the boat was about to leave. Classic set up for disaster.

 

I do have the added insurance policy to cover both the camera and housing should it get flooded, lost or stolen. I do like the idea of a keeping the moisture alarm in the event the pressure switch fails. With the moisture sensor still working along with the vacuum still in play during a dive is good backup. In addition, God only knows what the baggage handlers do to your housing even when packed in a Pelican case. I have a few scars on the case already that are worth noting.

 

The new unit out by Backscatter looks very appealing too but I have not seen any reviews on it yet. With regards to the light on it I don't have a opinion as to whether it is better to be external to the housing vs. internal for the Housing Sentry nor do I have an opinion for the seal on the Backscatter system and whether its disconnect is any better than the stainless steel from the Housing Sentry. So far the Housing sentry has held up on over 3 dozen dives at recreational depths.

 

One feedback on the Housing Sentry is that many people prefer to remove the hydrophone since they don't use it anyway (and complain that the cord gets in the way). The Housing Sentry uses a differenct port. I personally like the option of having a mic available but honestly have not used it yet. I will when I get into experimenting with video this year.

 

One thing not mentioned in any discussion that I have seen is that for those individuals that have masks with the colored filters on them will have any difficulty seeing the blinking green or red indicator lights for either vacuum indicator. I know that the green indicator light looses some of its color in the Housing Sentry when in the water. While I still can see it easily blinking underwater it definitely is not as green underwater. There is a concern that if I were to slowly lose vacuum and the color shifts to red that I might not be able to pick it up as readily. I don't know about the Backcatter light indicator and if it does the same thing with the same colors. Nor have I used a mask with a red filter on it and if that would disrupt seeing the change in indicator color should it shift from blinking green to blinking red if vacuum were to decay off due to a slow leak.

 

The last question is just how much vacuum should one pump the housing down to and whether or not it is actually good for the seals? I have not seen a figure on what vacuum is "enough". Surely some of the vacuum must be pulling somewhat on the rubber o rings and will drawing a vacuum cause them to unseat or distort over time with the added sea pressure acting in the same direction?

 

One final note on using a vacuum system it is nice to know that having a vacuum will help keep the housing closed in the event that a latch were to accidently come loose or not snapped into place at all before or during a dive. I did try to pull apart my housing with the latches not latched and the halves would definitely NOT come apart. However, I did draw a pretty high vacuum when doing this (15" Hg).

 

My two cents.

The Meltdownman

What can you tell me about the hydrophone connection.What size etc.

We recommend 10" of vacuum.

Thanks

I actually put my housing together and vacuum seal it the night before or hours before I am diving. Then I test to see if there is a vacuum just before I go out on the boat. If the seal is going to fail it will most likely be during this time. I dont see the point in an electronic part to keep monitoring the vacuum during the dive especially if it cost an extra $200.

 

Regards Mark

I (used to, because it quit working by itself some months ago) have a Hugycheck with its permanent monitoring and I think it is a good idea. Pressing buttons during the dive etc... may cause a leak (it did to me) even after being perfectly watertight on the surface. If I were to get a vacuum system I would get one with constant monitoring and, please, a reliable one...

Did you press every control button on your vacuum housing on the surface before the dive?

If I leave my manual pump connected to my vacuum housing on dry land and test every control button wouldn't this also find out potential control button o-ring failures. One could also find it easy to located which control button o-ring is failing and doing so in a much safer environment (outside of water).

Regards Mark

I did not. The advantage of constant monitoring over one-time-check cannot be discussed, what can be discussed is if it is worth the extra price etc...

One plus of constant monitoring is changing lenses etc... fast and jumping back in the water without having to wait a longish time.

One drawback of the hugycheck is that it quit working, so the water alarm quit working too since it is the same circuit... I went from diving with water alarm plus constant vacuum monitoring to "faith" diving

 

I (used to, because it quit working by itself some months ago) have a Hugycheck with its permanent monitoring and I think it is a good idea. Pressing buttons during the dive etc... may cause a leak (it did to me) even after being perfectly watertight on the surface. If I were to get a vacuum system I would get one with constant monitoring and, please, a reliable one...

The Hugycheck indeed isn't flawless! When i put my housing under a vacuum the green LED blinks and keeps on blinking, also overnight or longer. Last week i was using my housing in Spain and almost every day after a day of diving i discovered some tiny drops inside the housing. I emailed the manufacterer about it, and (as usual) they said it's most likely that the drops of water fell from my hair or that they are originated from the wet outer edges from where tiny drops spash in when you take the 2 halfs from the housing apart. But later that week i discovered that after a day of diving my camera body was wet too! Especially around the AF-ON button there is a rim around the button on the camera and with a balloon air blower i could blow out salt water. Fortunately my camera body still works fine, because it's weather sealed (advantage of a pro-body?). More accurate examination of the housing showed that the AF-ON button was having a slight leak. I put my housing under a vacuum without a camera and via the port i could see a small drop of water on the inside of the AF-ON button (the housing was still wet on the outside from the rinsing); no doubt about it, a leak. The Hugycheck always indicated that the vacuum is still present. Apparently a few drops of water in the housing do not cause a detectable pressure increase, which makes sense to me because the pressure increase is indeed minimal. BTW, an overnight green blinking Hugycheck was still green blinking the next morning, so based on hugycheck my housing was always perfect.

Anyway, Pascal from Hugyfot was so kind to send me a few new buttons, O-rings, spacers and some extra strong replacement springs which they sell for tech dive photographers who want to take photos up to 150 metres depth. My personal belief is that stronger springs put slightly more pressure on the O-rings, which will make them close better. Pascal denied it would make any difference, but i feel a little more confident about it this way. Fingers crossed the next trip! My housing is now almost fully equipped with extra strong springs except for two buttons (he didn't send enough springs...)

cheers, Udo

Udo,

What was amount of the vacuum you were using for your camera? I always wondered if too much vacuum was not good for the seal. On the other hand would it be better to have the vacuum at a level that was just above the point where the green light will change to red so that a very small leak would be detected as the vacuum decayed slowly away? The dial on these vacuum gages are broken up by one half inch increments of vacuum and therefore the resolution is not all that good for detecting very small changes in vacuum readings. I don't know if a vacuum gage with more precision would be a better way to help detect a very small leak.

The other feedback I have on this topic: is anyone recording the vacuum when first setting up the system and recording the vacuum just before a dive to see if there is a slow leak? I usually draw a vacuum overnight and check it again in the morning but from Udo's experience I am not sure this would catch such a small leak. Has anyone caught such a small leak before by performing a vacuum drop test (i.e. check/record the vacuum over a period of time)?

By the way thanks Udo for the feedback on your experience. I think most people have gotten the impression that these systems will detect leaks in all circumstances. This obviously is not the case in your circumstance. I will certainly be more sensitive to the indications of moisture buildup inside the housing now that you have you have shared your experience.

Sincerely,

The Meltdownman

Udo,

 

What was amount of the vacuum you were using for your camera? I always wondered if too much vacuum was not good for the seal. On the other hand would it be better to have the vacuum at a level that was just above the point where the green light will change to red so that a very small leak would be detected as the vacuum decayed slowly away? The dial on these vacuum gages are broken up by one half inch increments of vacuum and therefore the resolution is not all that good for detecting very small changes in vacuum readings. I don't know if a vacuum gage with more precision would be a better way to help detect a very small leak.

I normally make the vacuum until the red light changes to green and not more for the reasons you mentioned. According to the manual this is -200 mBar (so actual pressure in the housing will be approx. 800 mBar). I guess there is still a tolerance in this vacuum as temperatures and atmospheric pressure may differ too (a larger pressure difference then a volume decrease of 2-3 drops). When i wanted to see whether i could see water leaking in, i made the housing as vacuum as a the vacu-vin pump allowed me to, and that worked, because i saw a drop of water hanging on the pin of the button when i pushed it.

I never did a pressure drop test with an accurate pressure gauge. Possibly something would be visible a week ago, but hopefully now not anymore because i replaced, cleaned and greased most of the O-rings myself now.

Cheers, Udo

I am confused by the worry of pulling a vacuum in the housing having a deleterious effect on the o-rings. Pulling a vacuum in the housing is the same physics as putting pressure on the outside and at 200 mbar delta that is the same as diving to about 2 meters or a little under 7 feet or so with 1 atm in the housing. Since we routinely dive a bit deeper than that I don't see the problem unless somehow doing this in air is far worse than doing this in water.

So can someone please explain the worry?

Bill

Bill, I think people might be worried that if they leave their housing vacuum for sometime like over night that some of the housings o-rings maybe compressed over time quicker than if you didnt vacuum the housing...............? Like if I put a vacuum 12 hours before I dive it would be like taking that housing for dive for 12 hours (even if its a shallow depth respectively) and the o-rings would be placed under some form of stress.

So say if your dive for an hour twice a week at the end of the year you have racked up 104 hours which your housing o-rings have been under stress. Now you add putting your vacuum seal on the night before each of those 2 dives (10 hours before your dive as an example) and after a year you have put an extra 1040 hours of stress on those O-rings.

On that basis one does have to think O-rings will be compressed quicker when using a vacuum seal.

Solution to the issue? Change your main body and port o-rings more often. Be more diligent when you do put a vacuum in your housing. Press all the controls buttons and check the vacuum pressure again to see if there has been a noticeable drop in the vacuum?

Maybe there is a recommend higher vacuum pressure which we can test the housing, safely on dry land to double check the condition control button o-rings.........? Take the housing to that higher vacuum pressure and use all the control buttons and see if there is a change in vacuum............What do you think???

Regards Mark

Another Idea is that housing manufacturers look at using different Durometer rubber for their O-rings. Using a higher durometer rubber to have a stronger, longer lasting o-ring when used in suitable applications. Just like using 90 Duro O-rings on your Scuba cylinders. They cost about the same and last much longer than the standard 70/75 Duro o-rings.......? Might not work on those housing who main body o-rings has alot of bends but I cant see a problem with those round o-rings like for ports/extensions and domes...........?????

Regards Mark