Setting up my Nauticam 5dmIII housing for the first time and was wondering if someone can help me understand some of the basics I still don't understand:

 

1) I have an older style vacuum port that has a gauage that is listed in in/Hg. How much vacuum I should pull on the housing when diving? All the recent videso I could find on this only go by a colored blinking LED which I don't have. Around 13in/Hg the vacuum pump was making a clicking noise when I pulled it back every time and it sounded like I was starting to stress what I assume was the bladder inside the hand pump but wasn't sure what's normal and if that was too much. I left the housing at 15in/Hg overnight and it held for 24 hours. 

 

2) I'll mostly be taking my housing from warmer air into colder water that's ~40F (4C). Do people put silica gel packets in their housings or how much is condensation/moisture going to be a problem? I know some people soak their cameras before diving but it's unclear to be how much this is going to help and worried condensation or fogging might still be a problem.

 

3) I have a Nauticam FLash trigger for Canon which takes two CR3032 batteries and the user manual says it's good for 5000 flashes. I'd really like to know the standby time too (powered on but not being used), does anyone have any idea what that might be? Obviously I won't leave it on but it might happen or might be using it for 8 hours non stop and would be good to know. Part Number: NA-26301

Edited April 10, 20241 yr by brightnight

Most sources say that the vacuum light goes green at 200 mbar which is about 5 in Hg.  15 in Hg is probably a bit too much and I would stick to around 5". 

 

Regarding fogging, aluminium housings are generally a lot less prone to fogging, but it can still happen.  It depends on how humid the air is when you close the housing.  4°C is quite cold so you would want fairly dry air inside the housing to guarantee it won't fog on you.  For example if the air is 20°C and the relative humidity 30% then the dewpoint is right about 4°C.  This chart allows you to estimate the dewpoint:

https://www.hardwareinterviews.fyi/t/why-does-condensation-form-on-the-outside-of-cold-glass-on-a-hot-day/19/2

 

Start at dry bulb temperature and go up vertically to the relative humidity (blue line) then horizontally across to the the 100% RH curve.  This provides the dewpoint temperature of the air and when it cools to that temperature, water starts to condense.

 

As to what to do about it it would depend on your atmospheric conditions on the day  the hotter and more humid the air the more likely it is to fog.  An easy way to help is to purge the housing with air from a scuba tank which should be bone dry immediately before closing up.  The vacuum will also help a little. 

 

Aluminium housings normally don't fog as the metal gets cold quicker than the glass and the moisture if any will condense on the metal walls.

 

I recall that some triggers switch themself off when the camera is off, There was a post on this topic a little while back- possibly on Wetpixel?  Can't say for certain about the nauticam, but I recall they have a very long battery life.

I assume I should only put my battery in the leak detection circuit when I will be using it as I don't have a switch to turn everything on or off.

 

I tested my leak detection circuit and it works (blinking a red LED and beeping) when I apply water to the contacts. In videos online I’ve seen the more modern Nauticam housings have an LED that goes green when the vacuum is pulled and red when the vacuum is released. I assume that because my leak detection system is older that it doesn't have that functionality. Is it worth it to upgrade it and is that something I can install myself?

null

 

I had that old leak detector in my previous Nauticam housings and never removed the battery. It lasted months if not a year.
If you already have a separate vacuum circuit, I don't know if you should change it. Do you have just the pressure gauge or also some kind of alarm?

In the current Nauticam housing I have the latest version that integrates leak detector and vacuum with the multi color led. The circuit also has a switch because when it is on the led flashes red and then drains the battery. It does not use a CR2032 but a fatter version, CR2450.
I turn it on and vacuum the housing the night before the dive and often take it apart the day after the dive. So the led stays on two days and I dive at least twice a month. the current battery has been there for almost two years.
 

The leak detector is quite simple, just a circuit that detects increased conductivity when you bridge the terminals with a little water, it would have negligible current use unless it activates.  So I would think quite safe to leave the battery in place.

 

Regarding the vacuum circuit, the Nauticam system is quite good but the system you have also works.  You could install the the Nauticam circuit probably fiddly but possible, though installing the LED my be a little tricky, you might be able to use the LED window on your current housing for this purpose, if the LED supplied fits.  It will depend if you can find room to mount all the needed components. 

 

You would get similar functionality to the Nauticam system with a Vivid Leak Sentinel and it would be  a lot easier to install as it only needs a free M14 or M16 port, you would likely install where you have your current vacuum valve.

11 hours ago, Davide DB said:

I had that old leak detector in my previous Nauticam housings and never removed the battery. It lasted months if not a year.
If you already have a separate vacuum circuit, I don't know if you should change it. Do you have just the pressure gauge or also some kind of alarm?

In the current Nauticam housing I have the latest version that integrates leak detector and vacuum with the multi color led. The circuit also has a switch because when it is on the led flashes red and then drains the battery. It does not use a CR2032 but a fatter version, CR2450.
I turn it on and vacuum the housing the night before the dive and often take it apart the day after the dive. So the led stays on two days and I dive at least twice a month. the current battery has been there for almost two years.
 

 

Mine uses the CR2032, and I turn the vaccum detector on the afternoon/evening before the diving day, turning it of in the afternoon the next day (so it's on roughly 24 hours).
Diving usually 3 times a week, batteries last roughly 2 months before I start to see some sort of low battery indicator flashes, but this is Indonesia so they might not be the best, and environmental conditions might also be at play.
I was using Panasonics with expiry date in 2030, but switched to Energizers which seem to hold a little better.

Edited April 11, 20241 yr by bghazzal

Appreciate all the advice and suggestions! Looked into many options to add a vacuum sensor but they are all pretty pricey for what it is. Still, would be nice to have for peace of mind and might allow me to preemptively save my rig before the water alarm goes off. Now that I've confirmed that my setup doesn't have the capability to indicate if there is a vacuum or if the vacuum is lost, I think I might just build my own sensor system. Looks like there's plenty of room for a small board in my housing and I can pop an LED indicator up near the LCD window. Will make a DIY post so others can follow if I decide to make one.

2 hours ago, brightnight said:

Appreciate all the advice and suggestions! Looked into many options to add a vacuum sensor but they are all pretty pricey for what it is. Still, would be nice to have for peace of mind and might allow me to preemptively save my rig before the water alarm goes off. Now that I've confirmed that my setup doesn't have the capability to indicate if there is a vacuum or if the vacuum is lost, I think I might just build my own sensor system. Looks like there's plenty of room for a small board in my housing and I can pop an LED indicator up near the LCD window. Will make a DIY post so others can follow if I decide to make one.

 

If you build your own, do post details - it'd be really interesting.

 

On cost, yeah, they are a little pricey but, believe me, the cost is nothing compared to the cost of resolving a problem if there is a leak! I managed to get a half-teaspoon of water in my housing some years ago. Cost of despatch to repairer and back, $200; cost of repair etc,  $1200; cost on the wear and tear of my nerves, immeasurable. Vacuum valve? Never leave home without one.

I do not have Nauticam housing/flash trigger for Canon, but I have Nauticam flash triggers for both Olympus and Sony and Nauticam housings for EM5II (just sold), EM1II and A7R5. Fogging and battery issues are probably similar...

 

The batteries for housings and flash triggers (both CR2023 and CR2450) last usually long (1-2 years with approx. 70 - 100 dives/year), even when one leaves vacuum and flash triggers on overnight, e.g. when diving in the early morning is planned and I want to sleep as long as possible. I always have a bunch of of spare batteries for replacement with me and sometimes this was already required (I have a spare flash trigger with me also, just in case)...

 

The Nauticam housings are very resistant to fogging (I do not use silica gel packages). I had fog only twice so far:

 

#1. I assembeld my NA-EM1II on a rain day (=constantly raining from 00:00 to 24:00) at the equator in a small hut covered with banana leaves and water was dropping in at some places. On the subsequent dives I had fog on the domeport. This happened just once, all the other dives were without fog...

#2.: I assembled my NA-A7RV, also on a full rain day in an apartment in Tyrol/Austria. On the subsequent dive in a mountain lake there was fog inside the domeport. When I inspected the housing later there was a tablespoon of water inside (neither vacuum system nor moisture detector indicated this). Responsible for this tablespoon, that for sure produced the fog, was either an extension where a part got loose because of the lack of screws as provided by Nauticam (there is a tread on this somewhere here), or just me being sloppy when assembling the housing and trapping the water unintentionally - I will never know for sure...

I had numerous other dives in cold mountain lakes with Nauticam housings and never had fog on them ...

 

 

Wolfgang

Edited April 11, 20241 yr by Architeuthis

Always seal your housing in an air conditioned room if possible. Next best is outside. A non climate controlled room tends to be the highest possible humidity. 

On 4/9/2024 at 4:47 PM, brightnight said:

2) I'll mostly be taking my housing from warmer air into colder water that's ~40F (4C). Do people put silica gel packets in their housings or how much is condensation/moisture going to be a problem? I know some people soak their cameras before diving but it's unclear to be how much this is going to help and worried condensation or fogging might still be a problem.

As said, this is usually not a problem but assembling in the least moist space as possible (AC) or in very dry air.  Having said that, I have frequently taken an Alu housing from 80 C to 55 without any issue (or from 65 to <0 C... but the air is really dry).  I do not put dessicant in my housings.

 

The other thing I would strongly suggest is being weary of the water that you rinse your housing in after the dive.  A 40 deg housing getting dumped into an 80 degree rinse tank is a great way to flood a housing.  I let mine warm up and make sure it is similar in temperature to the rinse tank before putting it in.  I do use running water to wash the front of the port after I get up, but will then let the whole housing warm prior to a submergence and/or soak and then only if the rise water is not hot.

1 hour ago, ColdDarkDiver said:

As said, this is usually not a problem but assembling in the least moist space as possible (AC) or in very dry air.  Having said that, I have frequently taken an Alu housing from 80 C to 55 without any issue (or from 65 to <0 C... but the air is really dry).  I do not put dessicant in my housings.

 

The other thing I would strongly suggest is being weary of the water that you rinse your housing in after the dive.  A 40 deg housing getting dumped into an 80 degree rinse tank is a great way to flood a housing.  I let mine warm up and make sure it is similar in temperature to the rinse tank before putting it in.  I do use running water to wash the front of the port after I get up, but will then let the whole housing warm prior to a submergence and/or soak and then only if the rise water is not hot.

40deg -> 80deg? How does that happen, in either Celsius or Fahrenheit? 

2 hours ago, Dave_Hicks said:

40deg -> 80deg? How does that happen, in either Celsius or Fahrenheit? 

In Celsius, that water would be FAR to warm to dive 🙂

 

If bottom water is 40 (which is brisk) and you are in a heated boat or vehicle, or its really sunny and stagnant you can have a nice warm rinse tank. Just takes a really strong thermocline. Much more common is a nice dive on a day with strong upwelling so the water temp is in the mid to upper 40s and the boat is sitting in some glorious sun. 50 F (bottom water) to 80F (rinse tank) is even easier, and we have that happen frequently.  We have multiple lakes here that stay in the 40s all year and the surface can be dreadfully warm (so not just in the ocean). Also a good reason just to swap the rinse water to fresh and colder water when you come up, if the temp differential isn't too much everything is happy.

 

23 hours ago, ColdDarkDiver said:

The other thing I would strongly suggest is being weary of the water that you rinse your housing in after the dive.  A 40 deg housing getting dumped into an 80 degree rinse tank is a great way to flood a housing

 

Is this type of flooding a results of warming the metal housing up quickly that the metal housing expands faster than the o-ring leaving a gap for the water to get pulled in or what's the underlying cause?

4 hours ago, brightnight said:

 

 

Is this type of flooding a results of warming the metal housing up quickly that the metal housing expands faster than the o-ring leaving a gap for the water to get pulled in or what's the underlying cause?

I think it is the rapid temperature change causing the air to expand (and this should be much less of a problem if a vacuum was pulled), but it has always surprised me - and I have flooded at least a strobe or two this way.  In those cases, it was always a plastic housing not metal and not on something that I had pulled a vacuum on.  But I just am delicate with all my housings, especially the ones with the expensive cameras inside when dealing with rapid temperature changes.