Which dive computers provide average depth in their logs?

[Centrals]

My SAC(6 - 10L/min) varies from dive to dive ie. depend on many factors eg. current(against or with), the kind of buddy I was diving with etc etc. When the spg hits 100 bar then it is time to ascent to shallow and finally surface with min of 50 bar.
Different approach if it is tec dive.

 

[Glenndini]

I have a slightly off topic question here. I note that the post above uses L/min as SAC rate i.e. Surface pressure air volume per minute.
cylinder volume (litres) x pressure used (bar) / time (mins) / depth (bar) ie: 10 litre x 140 bar /20 minutes /3 bar (20 metres depth) = 23.3 L/min.

The post by Scubadada shows the SAC rate as pressure per minute and RMV refers to cu.ft./min of volume per minute.

I note that my Suunto and DM5 software also refers to SAC rate as L/min.(volume/minute) but many on this esteemed website also refer to SAC as pressure per minute.

I have also found formulas on different websites referring to 2 differing calculations. SAC=L/min. (or cu. ft. /min) or SAC=bar/min (psi/min)?

Is this a known inconsistancy between different countrys/regions etc. or simply some confusion?

 

[tursiops]

I have a slightly of topic question here. I note that the post above uses L/min as SAC rate i.e. Surface pressure air volume per minute.
cylinder volume (litres) x pressure used (bar) / time (mins) / depth (bar) ie: 10 litre x 140 bar /20 minutes /3 bar (20 metres depth) = 23.3 L/min.

The post by Scubadada shows the SAC rate as pressure per minute and RMV refers to cu.ft./min of volume per minute.

I note that my Suunto and DM5 software also refers to SAC rate as L/min.(volume/minute) but many on this esteemed website also refer to SAC as pressure per minute.

I have also found formulas on different websites referring to 2 differing calculations. SAC=L/min. (or cu. ft. /min) or SAC=bar/min (psi/min)?

Is this a known inconsistancy between different countrys/regions etc. or simply some confusion?

Different agencies and instructors and divers use different definitions. There is no standard. Volume per time is the most common, I think, but pressure per time is more readily calculated and useable for lots of folks.

 

[DON-PNW]

I dive the Mares Icon HD Net Ready, it tracks and logs average depth and SAC Rate among others. I can't speak of all computers but I at one time imported my raw data into excel and the average depth was a mean average. I pay particular attention to my SAC rate, especially when it is abnormally high for me. One way not mentioned yet that I use SAC Rate for is the ability to determine anxiety, comfort level, activity level etc. For example, in the past year I have logged 114 dives, I have looked at each SAC rate and now have a very good idea at what my at rest SAC rate is and what my at work SAC rate is, furthermore I know what my SAC rate is for each of the dive sites that I dive regularly. If I were to dive a site that I average a .5 SAC rate and one day I dive the site and my SAC rate is 1.0 then I know that something is not right for me and I can do something about it.

 

[DON-PNW]

(Stolen from another post)
SAC must be calculated in order to figure out RMV. SAC is tank dependent and is measure in PSI/Minute. This is actually valuable to know while underwater since your SPG measures in PSI. It's good to know for instance that your usual rate is 15 psi/minutes.

RMV is measured in cu ft/minute and is useful for planning gas requirements before the dive as in .5 cu ft/minute at the surface which then needs to be corrected for depth (ata's).

 

[ColoDale]

My two Oceanics will give average depth on download.

 

[pelan-pelan]

I am curious, why are you fixated on "average depth"?
AND: Is there a standard definition of "average depth"?

My computer allows me to download my profile and get an exact picture of my dive. I really don't care about depth details and am more interested in things like sawtooth behaviour and fast ascents. Early on I used this information to temper my up and down behaviour a bit. I had a video camera and would randomly chase fish up and down during the dive. I don't do that anymore.

So: What information does average depth provide?

Good question. I often dive in places where having a computer (tablet/laptop) is excess baggage even if it makes it through the journey. Shock horror, I use a paper log book. When I look back at say the last 80 dives, I can compare air consumption, max depth, average depth, temperature and all the features of the dive that I have noted such as current, fish-life, gear used.

I use the same computer so the average depth is comparable. I am a recreational diver. I sometimes don't dive for over 6 months. When considered alongside all the information, average depth gives me clues (clues not answers) to my dive fitness, how comfortable I was with the dive (which is the result of how out of practice, dive conditions, dive operation etc). It may raise questions. Is it what I expected? So what went on with a dive that on average was shallow, yet the air consumption was high? Went deep and then came up or finning against the current or not as fit as I thought, etc? I then run the dynamic log to help find the answers.

I am a recreational diver. I need to reflect on my dives and use that information to plan my next dive. I consciously avoid "sawtooth" dive profiles, but I try not to be complacent and all the information I can get to monitor my dive helps. With gaps of over 6 months, there's always a re-learn/re-think. (Scope for another thread on stupid mistakes on first-dive-back "My regulator isn't working", "Try turning your air on", "Dohh". At least it was discovered in a buddy-check - which is what they are for.)

To others, thanks for the answers about which computers provide average depth on the dive computer log (without the need to connnect to a computer). The discussion about what an average is has been interesting and relevant. It is important to know, particularly in the event that you change computers. The discussion on the adjacent thread regarding buying a dive computer is very interesting in this context.

 

[scubadada]

(Stolen from another post)
SAC must be calculated in order to figure out RMV. SAC is tank dependent and is measure in PSI/Minute. This is actually valuable to know while underwater since your SPG measures in PSI. It's good to know for instance that your usual rate is 15 psi/minutes.

RMV is measured in cu ft/minute and is useful for planning gas requirements before the dive as in .5 cu ft/minute at the surface which then needs to be corrected for depth (ata's).

This is my understanding also

 

[Hoag]

While it is not a dive computer, I dive with a Citizen Aqualand Dive Watch. In its Log mode, it displays average depth (and no, I don't know whether it is Mean, Median or another type of "Average"). I use it simply this feature as a point of interest.

I also use an iPad app for logging (as opposed to a paper log) that is called "Dive Log". It has a stats page that I can pull up that shows, among other things the average depth of my dives. I do know that this one calculates averages as if I have 3 dives of 50ft, 60ft and 70, ft, it will say my average is (50+60+70)/3 = 60ft.

Don't know if that helps at all.

 

[dmaziuk]

I was trying to give @giffenk the benefit of the doubt, but I ran out of patience.

What benefit? By definition of average, a dive's average depth is half of its max depth. I suspect that's not the "average" you're talking about, so the question is perfectly legitimate: what are y'all talking about?