First Rebreather Questions

[flymolo]

Could other people chime in on this point?

My understanding has always been that the whole point of huds (for example the narked@90 one) is that once you ppo02 drops or climbs too much, it will go into a disco mode and warm you.

Does it actually happen that you become so used to it that you can ignore the warnings?

the fathom hud has the disco mode and the low/high po2 range can be programmed. i don't think others have it. the regular shearwater hud doesn't.

i would consider a hud mandatory

 

[inquis]

I used a [ETA: Fathom] HUD for a week while my Nerd was down. I DEFINITELY noticed when it started flashing red on some ascents (PO2 below 1.0). I also wasn't consciously watching it, but the green flashes were comforting. On the flip side, it took a couple minutes for me to notice that it wasn't blinking at all after it was surreptitiously turned off midway through a training exercise.

That said, it does need to be in your peripheral vision to stand a chance of being useful. I've heard that some will tuck it under a cover and will only pull it out if their "normal" monitor fails.

As an aside, I would frequently see a teammate's HUD flashes reflected off their mask. If they somehow missed it, there's a decent chance I would see it and could say something.

 

[Wibble]

Had a DSV and bought a BOV following a caustic bailout. Used that for 15 months then switched back to a DSV using a necklaced bailout.

Much more convenient, less of an embuggerance and just works better.

Just my opinion after using all three (DSV with reg on bailout; a BOV; DSV with necklaced bailout). No intentions of going back to the BOV.

 

[piranhaman00]

Had a DSV and bought a BOV following a caustic bailout. Used that for 15 months then switched back to a DSV using a necklaced bailout.

Much more convenient, less of an embuggerance and just works better.

Just my opinion after using all three (DSV with reg on bailout; a BOV; DSV with necklaced bailout). No intentions of going back to the BOV.

Nice review. My current plan is the DSV with necklace 2nd stage, that is also what the instructor teaches.

 

[davehicks]

You don't need a HUD if you have a Petrel 3. The P3 has a strong vibration function that you can configure to alarm on Hi/Lo PPO2 levels.

I don't get the sadness reactions. Do you feel a red LED is somehow better than a Haptic alert? Both do the react same thing.

 

[lermontov]

Could other people chime in on this point?

My understanding has always been that the whole point of huds (for example the narked@90 one) is that once you ppo02 drops or climbs too much, it will go into a disco mode and warm you.

Does it actually happen that you become so used to it that you can ignore the warnings?

The HUD is a warning to look at your hand controller -The nerd is more than just a HUD with smithers code though - you have more info regard to PO2 depth and time and deco obligation - a back up computer - I use my nerd info more than my controller - especially when Im fluffing around with tank, gear etc and my hand is busy

 

[Wibble]

I don't get the sadness reactions. Do you feel a red LED is somehow better than a Haptic alert? Both do the react same thing.

The HUD is a second alerting interface that is literally in your face, even if it is a Nerd,

Wrist computers slip around and aren’t in your field of view, especially If scootering, climbing down a shot line in a current, or other forms of task and arm loading. Also in very poor visibility.

Personally I’m uncomfortable with one computer even with haptics.

 

[inquis]

Much more convenient, less of an embuggerance

Would you please elaborate when the DSV+necklace was more convenient for you than the BOV? Outside of scootering, nothing comes to mind, but I've also never used a DSV.

 

[rjack321]

Could other people chime in on this point?

My understanding has always been that the whole point of huds (for example the narked@90 one) is that once you ppo02 drops or climbs too much, it will go into a disco mode and warm you.

Does it actually happen that you become so used to it that you can ignore the warnings?

The narced@90 / shearwater will flash 5x green-green-green or 5x red-red-red at you if you are above 1.5 or below 0.7 but there's no "disco" mode. Disco is a Fathom HUD feature only

It is possible to look over or past a HUD if it's not adjusted properly or you're intensely tunnel visioned.

 

[davehicks]

The HUD is a second alerting interface that is literally in your face, even if it is a Nerd,

Wrist computers slip around and aren’t in your field of view, especially If scootering, climbing down a shot line in a current, or other forms of task and arm loading. Also in very poor visibility.

Personally I’m uncomfortable with one computer even with haptics.

Have you tried it? A haptic alert is noticed no mater what position, task, or visibility conditions exist. Even with a hud the first thing you do after an alert is look at the actual computer. So i feel that is a non issue.

I dive with two computers but only one has PPO2 readouts. If that fails I end my dive. Now if I did dives that did not enable an immediate exist to the surface I would get a Nerd or similar.