diverdoug1 58 Posted November 11, 2013 (edited) its really not that much difference with passive system. i could pull partial vacuum the night before or even two days before. just before the dive or during the morning prep i plug in my hand pump with an analog gauge or a digital gauge. i prefer all mechanical. if fact i sometimes check if the vacuum is still there just before i jump in by unlatching the snaps or try pull out the port. of course if you have vacuum you will have resistance and usually can't be pull apart. simple physics. i am okay with electronics and i have both but if i were in a one month trip in the middle of nowhere i think the passive or mechanical system offers me less trouble or risk. each to their own and as long as it works and let one concentrate on the shot rather than having constantly worry about the vacuum. bring spare batteries. With the electronic system you do not have to carry your gauge or unsnap jyour housing or try to remove your port (sounds unwise and a bit brutal). It also tells if you start to loose the vacuum with a warning light. So I know IMMEDIATELY before I go in the water that my vacuum is still intact (and nothing has gone awry in the time period immediately before going in the water). Edited November 11, 2013 by diverdoug1 Share this post Link to post Share on other sites
E_viking 30 Posted November 11, 2013 One caveat with the Leak Sentinel system (Vivid Housings). When you turn the unit on, it senses the pressure in the housing as atmospheric pressure (1 bar) and measures vacuum relative to that pressure. So if you pull a vacuum at night and then turn the sensor off afterward, when you turn it on in the morning, it will sense the internal pressure (approx. 0.8 bar) in the housing and measure vacuum relative to that pressure. So, although you may have a vacuum in the housing, the sensor will indicate that there is not a sufficient vacuum in the housing and will blink red. Although I have not dove the unit yet, I plan to pull the vacuum at night after the unit is assembled for the next day and monitor it for 30-60 minutes. If all is well, I'll turn the unit off to conserve battery, but retain the vacuum in the housing. The next morning, I'll bleed air into the housing to eliminate the vacuum as evidenced by the hissing sound. If there is no hissing, then I have a problem. Then reestablish the vacuum with the proper green light indication. Using this procedure, I should get a 14 day dive trip out of one battery, or at least I hope to do so. I cannot comment on how other systems work. I have used the System this summer. My general was to vacuum it in the evening before. Then I simply let it blink the night through and between dives ( if I did not have to open the Housing). The Cell is still going strong. So, it does not really seem to be an issue. However, I always bring some extra Cells. /Erik 1 Share this post Link to post Share on other sites
gorantrener 4 Posted November 11, 2013 back to the subject, i had leak in my nimar housing twice in the past (with nikon d 80). im not using it anymore,because upgraded to aquatica. first leak was due to main o-ring failure, which slipped out of its place right before the closing of the housing (or, during it!), and second time it was failure of the o-ring on on-off command. in first case, flooding was something like 1 cubic centimetre per second, and in second case one drop every few seconds, directly on the shutter (because it is placed in the middle of on-off command on the body). fortunatelly, in both cases managed to save the camera, because it was visually obvious that there is a leak.(transparent housing) housing is still healty, because it has no electroparts. even in the case of flooding drops directly on the shutter, after carefull rinsing of the shutter (body turned upside-down) and sensitive blowing with the air from the cylinder, D80 still functioning perfectly Share this post Link to post Share on other sites
Gudge 59 Posted November 11, 2013 Was your vacuum test done by compartment or on the entire boat at one time? Entire boat at one time. Conventional submarines are much smaller than the nuclear boats you were on. DBF!! Share this post Link to post Share on other sites
JohnE 8 Posted November 12, 2013 Interesting. I spend a good part of my life in the US Navy nuclear submarine service and never encountered such a procedure except in a shipyard during overhaul and compartment testing. Now if you're snorkeling at PD and the head valve goes shut for an extended period, you do get a rapid, unintended vacuum. Was your vacuum test done by compartment or on the entire boat at one time? JohnE: Thanks for the background. What do you define as "extreme pressure"? I assume it's beyond normal rec. depths. Thousands of PSI. Way beyond normal diving depths. Share this post Link to post Share on other sites
JohnE 8 Posted November 12, 2013 Seal Check is an active, external vacuum monitoring system. It allows you, the user, to make a go/no go decision on housing integrity by monitoring the vacuum level in the housing. An internal vacuum check takes this decision from you. You must trust the designer of the kit. We opted for the external system because other factors can influence the result. Temperature changes, for example, change the level of vacuum in the housing (PV=nRT). The smaller the housing, the greater effect temperature changes will have on the system. Also the larger Gates housings take forever to pull a reasonable vacuum with a hand pump. An electric pump is necessary. Great thread, this is good stuff. Share this post Link to post Share on other sites
jonny shaw 16 Posted November 12, 2013 I have to say the Seal Check is one of my favourite pieces of kit, as John said when shooting on a big production knowing that the housing is not going to leak takes a huge stress off. Mine has proved its worth too and identified a issues before jumping in on two occasions and they issues weren't obvious at all. Share this post Link to post Share on other sites
bvanant 195 Posted November 13, 2013 Diving on the Damai (1), fell down in the camera room holding two housings, my 7D housing and my wife's video housing. The video housing was held up in the air, my head and the 7D hit the floor. Apparently the 45 finder on the 7D had enough torque on it to unseat slightly the clear back on the housing. No leak in the rinse tank nor at 10 feet but at about 80 feet I could see water pouring in around the o-ring that holds the plexiglass back in place. Pretty sure that a vacuum check would have seen this but not sure since it took a lot of pressure to push the o-ring from the groove and allow the water to get in, not sure if I could have gotten enough DeltaP to see the leak. Bill Share this post Link to post Share on other sites
John Bantin 101 Posted November 14, 2013 Surely the "resistance" was because Hugyfot were forced into inventing the vacuum system when their original redesigned housing mechanism wasn't very good? The current popularity is because vacuum leak detectors have been taken up by some eminent practitioners recently... ... and (recession-led?) paranoia! I never had a Hugyfot without Hugycheck. It's the reason I chose it! Share this post Link to post Share on other sites
Oceanshutter 121 Posted November 14, 2013 My wife's housing....she had a massage right before she put her housing together. Forgot the port oring...woops. Obviously the vacuum would have caught this. Luckily the insurance replaced the whole housing instead of just the electronics, and I now use her old one for video....5d mark II. So in the end it worked out for me! So in this case, I am glad it happened...though I was pissed at the time. Dustin Share this post Link to post Share on other sites
DocTock 7 Posted November 16, 2013 Diving on the Damai (1), fell down in the camera room holding two housings, my 7D housing and my wife's video housing. The video housing was held up in the air, my head and the 7D hit the floor. Apparently the 45 finder on the 7D had enough torque on it to unseat slightly the clear back on the housing. No leak in the rinse tank nor at 10 feet but at about 80 feet I could see water pouring in around the o-ring that holds the plexiglass back in place. Pretty sure that a vacuum check would have seen this but not sure since it took a lot of pressure to push the o-ring from the groove and allow the water to get in, not sure if I could have gotten enough DeltaP to see the leak. Bill I was a witness to the sound of this event and can report that the video system was gallantly saved, and Bill's head did not spring any additional leaks. Out of the 4 catastrophic floods at the Wetpixel Macro Workshop in Lembeh, one was a Nauticam system where the unfortunate user admits "I hurried and did not pay attention to a pinched o-ring." The other was an Ikelite housing where the leak ended up being due to a defect in a dome at the attachment point. Share this post Link to post Share on other sites
peterbkk 110 Posted November 16, 2013 The video housing was held up in the air, my head and the 7D hit the floor. That's called photographer's instinct. Reminds me of last February. I was in Harbin, China to photograph the ice festival. Carrying my Hasselblad H4D in my hand. Walking along gingerly on shiny ice; in shoes that just had simple rubber soles. The guide called me to see something over on my right, my body changed direction, my shoes did not. Went down hard. My butt, back and head hit the ice simultaneously, with a solid crack. First instinct: is the camera OK? Everyone is worried about me. But, I'm lying on back, dazed, but testing the camera's functions. Yes, it was OK. Then I started to think about whether I was OK. The guide told me later that I held the camera up the whole way down and gently cushioned its fall into my belly... Had a headache and dizziness for a couple of days. But the camera was fine. Here are some of the images: http://www.peterwalker.com/harbinice2013.html Regards Peter Share this post Link to post Share on other sites
Aquapaul 26 Posted November 16, 2013 I have had 3 minor floods where ht camera lived all three times. All 3 due to a gritty oring, Too many dives without cleaning and just plan carelessness. Share this post Link to post Share on other sites
DiverPam 13 Posted November 18, 2013 TImely topic....2 floods since 2000. First in 2000...rolled off the back of the boat with the rig. I have had it handed down ever since. Most recent flood...3 weeks ago. Port came off the front of the camera when it was handed to me. Epic flood...when huge bubbles instantly come up you know it is not pretty. I had done a leak check in the rinse tank before getting on the boat and set it on the camera table on way out to divesite. Apparently port came loose somewhere on boat ride. Lesson learned....double check the port after boat rides. Thank goodness for equipment insurance. And...have a vacuum system put it. Already have it ordered and housing in their hands. Not waiting on that one. Happy flood free diving everyone - Diverpam Share this post Link to post Share on other sites
johnspierce 25 Posted November 19, 2013 (edited) Time to do mine. - First flood was in the rinse tank back in 2005 or 2006. Front port was knocked askew resulting in total flood. - Second flood was about 6 months ago in Fiji. Still don't really know what happened, just saw bubbles coming from the top left of the housing where the surfaces mate. I was about 20 feet down and by the time I surfaced the entire housing was full. Opened it immediately, but didn't find anything obstructing the o-ring. I'm very careful with my gear, but I did just change from wide angle to macro, so obviously I did something wrong. BTW, the moisture alarm *did* go off, but the housing was already half full of water, so it really just added insult to injury. My flood insurance worked better than the moisture alarm thankfully At any rate, the one thing I am certain of is a vacuum system would most likely have prevented both floods. My new Backscatter vacuum system arrives this Friday. Edited November 19, 2013 by johnspierce 2 Share this post Link to post Share on other sites
diverdoug1 58 Posted November 19, 2013 Does anyone have any flood stories while a vacuum system was being used? Share this post Link to post Share on other sites
John Bantin 101 Posted November 23, 2013 I used the Hugyfot vacuum system and twice flooded my housings - with air! Share this post Link to post Share on other sites
Alex_Mustard 0 Posted November 23, 2013 I know of one Hugy and one other housing that flooded with sea water despite passing checks. But I know lots of photographers - and so have seen most things! A vacuum system is well worth having if you worry about flooding. I have never lost an SLR (film or digital), nor since using a vacuum system found that I hadn't put my housing together correctly upon checking it. But I still like having it. Alex Share this post Link to post Share on other sites
John Bantin 101 Posted November 24, 2013 I know of one Hugy and one other housing that flooded with sea water despite passing checks. Alex The corollary of that is that a vacuum leak test is a waste of time! Share this post Link to post Share on other sites
Alex_Mustard 0 Posted November 24, 2013 Except that I've seen 100s and 100s of photo dives when they have not flooded. Share this post Link to post Share on other sites
Larry C 24 Posted December 2, 2013 Dove from 2005 to 2013 with no floods except strobe. (Sea & Sea caps don't like the sudden pressure of jumping in the water, even when you can't use the strobe because it's a Whale shark snorkel). 2013, two floods. First flood was a bad o-ring on the button that unlocks the lh function knob. No damage to camera or lens, but the electrics in the housing were toast. $750 rebuild and about 20 dives later, the rebuilt housing flooded destroying the camera. Sync cord port nut had come loose and the port had 3mm of vertical play. Working with good vendors pays off. The shop that repaired it the first time redid the fix, this time with loctite on the nut, and bought me a good used replacement camera. Thank you Backscatter. 1 Share this post Link to post Share on other sites
Mark K 5 Posted December 14, 2013 1. video light: leaking o ring 2. inon z240: o ring slipped out 3. Nex 5n...housing springs got caught inbetween Share this post Link to post Share on other sites
divengolf 17 Posted December 26, 2013 Earlier in this thread, I noted that I have installed a vacuum system in my AD7000 Aquatica housing and was going on a trip to evaluate. Now I have completed the trip with about 20 dives on the system. I am completely sold on the system. Generally I set the kit up in the evening and let it set overnight with the vacuum established and the green OK light blinking. Every morning it was there to welcome me before the first dive. Added assurance that everything is watertight before my giant stride or back roll (without my kit!). A couple times I had to make an unexpected, rapid lens and port change. The vacuum system gave me added assurance that everything was tight. Definitely worth the minor cost compared to all that I have invested in my kit. I have a Leak Sentinel from Vivid Housings which has an electronic sensor and signal lights. This gives me a continual indication of a solid kit during the dive. I like this better than just using a purely mechanical system, i.e., vacuum gauge, since the gauge doesn't go in the water. Soon I'd expect that all quality housing will come with a vacuum system installed. If you're going to buy the Leak Sentinel, PM me as I have a couple comments that are not yet covered in the manual. Share this post Link to post Share on other sites
bvanant 195 Posted December 27, 2013 Sync cord port nut had come loose and the port had 3mm of vertical play. Working with good vendors pays off. The shop that repaired it the first time redid the fix, this time with loctite on the nut, and bought me a good used replacement camera. Thank you Backscatter. Well it is good that they got you a replacement camera, but as John Bantin suggests earlier the corollary to this is that they should have done it correctly the first time. Do they do the repairs in-house or do they have Devon do them? Bill Share this post Link to post Share on other sites
Larry C 24 Posted December 27, 2013 They do the repairs in house, AFAIK. I think that Scott, their technician did all the work. As someone who has been employed in a service industry for many years in the past, I'm aware that errors can happen and I'm always appreciative when I'm told, "we'll take care of it" and it's done. Share this post Link to post Share on other sites