Uemis Zurich vs. Hollis DG05 vs. Shearwater Predator

[eelnoraa]

if you think tech is in your future, just start to dive in a "tech compatible" way, so that you don't need to relearn the tech way, or worse, correct the bad habbit you developed. So skip the AI transmitter, put spg on your first stage, and get used to unclipping/checking/clipping.

I like Hollis service, sometime they just missed things on their first shot. Their first 212 2nd stage had a build in swivel which cant be swapped out. Now their DG05 with AI transitter.

 

[cciejames007]

Sounds like good advice and I could agree with you if I understood why. For example, when they told me to switch to DIN, made perfect since, its stronger and can handle a bit more of accidental abuse. There is a lot of things mentioned that makes sense, but I like to know why. So far, I haven't seen a reason why not to use the AI. I just see a bunch of posts of people saying, I don't like AI and someone else responding me either. Ok, lol doesn't tell me why not. Also, as a side question, does the Shearwater know tank pressure? Like is there a hose that connects it? Or do you just use a separate SPG? This one I'm just curious on not sure how it works.

 

[Jim Lapenta]

The predator is not air integrated. You need a separate spg. When getting into tech you need to change your entire outlook on diving. Yes it is recreational but you can die a lot faster if something goes wrong. It is all about risk management and what you can do to minimize that. An air integrated computer, especially with a transmitter, is an additional faliure point. You have a battery in the transmitter you need to worry about. Plus you have the synch needs of the transmitter with the computer. While most are quite reliable I have heard too many stories about lost signals. Another consideration is much of tech diving involves going into places where the transmitter could get damaged on something. Plus the transmitter is something else that a careless deck hand might consider a nice handle to grab.

A hosed computer has it's own issues. First of all is the hose itself. Another item to get snagged or tangled. It would necessarily have to be longer than the normal tech spg hose to make it easy to keep raising the gauge. There goes the streamlining that a simple spg and wrist comp offers. Air integration of any kind on a tech computer, except for a rebreather set up is nothing more than a gimmick. It relies on the gullibilty of recreational divers who have been suckered into spending lots of cash on computers that they really do not need. Why a vacation diver would need a $1200 computer is beyond me. Other than to say look how much money I had that my LDS now has.

Every tech program that I looked into started with tables and if a computer was used it was put into guage mode for the first dives. It is all about discipline. Other than caves tech diving on wrecks tries to plan and do square profiles whenever possible. A computer that tracks nitrogen every 30 seconds is just not really needed. I got my first tech cert in 2007. Did not get a tech computer until this year. It was all great lakes diving or practice for great lakes and wreck diving in general and the computer is back up. Following the computer IS NOT AN ACCEPTABLE PLAN in tech diving. When you take your first tech class and the first thing the instructor goes over will be how divers have died doing tech dives it will become clear. The plan takes precedence over everything.

In receational diving a diver can say screw the plan and rely on the computer if they see something 15 feet deeper than they planned. Not someone I would dive with but it is done. Because no one has ever told them how risky this activity is. Tech diving is a whole nother area. If you see something 15 feet deeper you note it and plan the next dive to check it out. It's all about discipline and how much a diver has or does not have. My tech instructor never even mentioned using a computer until the diver actually got some dives in and showed that they had that discipline. Then computers were mentioned as an option on down the road.

 

[cciejames007]

Very cool and thank you for taking the time to explain. The intro part to that really gives some good information. I appreciate what you wrote and the insight and I look forward to my classes and getting into it more.

 

[eelnoraa]

Sounds like good advice and I could agree with you if I understood why. For example, when they told me to switch to DIN, made perfect since, its stronger and can handle a bit more of accidental abuse. There is a lot of things mentioned that makes sense, but I like to know why. So far, I haven't seen a reason why not to use the AI. I just see a bunch of posts of people saying, I don't like AI and someone else responding me either. Ok, lol doesn't tell me why not. Also, as a side question, does the Shearwater know tank pressure? Like is there a hose that connects it? Or do you just use a separate SPG? This one I'm just curious on not sure how it works.

You are looking at it wrong. It is not about AI's advantage vs disadvantage. It is about the a lazy dive habbit (works in rec dive) vs. proper tech diving proceedure. Relearn is not easy, correcting old habbit is even harder. Like many of my mentors told me, see the end from the beginning. If you are going to be doing tech, just learn the tech way at the start.

Now, if you ask why AI is not used in tech diving. I think Jim gave you a very good over view. Every piece of equipment you bring on a tech dive should serve a purpose, not just nice to have especially if it introduces a failure point. So what purpose is AI serving that can't be done with a diver's brain and a spg as backup?

 

[Scott]

Sounds like good advice and I could agree with you if I understood why. For example, when they told me to switch to DIN, made perfect since, its stronger and can handle a bit more of accidental abuse. There is a lot of things mentioned that makes sense, but I like to know why. So far, I haven't seen a reason why not to use the AI. I just see a bunch of posts of people saying, I don't like AI and someone else responding me either. Ok, lol doesn't tell me why not. Also, as a side question, does the Shearwater know tank pressure? Like is there a hose that connects it? Or do you just use a separate SPG? This one I'm just curious on not sure how it works.

When I went through my tec course this was one of the topics of discussion I had with the instructors since I had an AI and wanted to use it along with a SPG. The main reason for it was so that I could have as an accurate swiming and resting SAC rate as possible. After that was achieved I removed it.
The concerns they expressed were; it's another failure point with the battery, transmitter could get damaged and someone may use it as a lifting point when you're climbing out of the water. All those are some of the common concerns you will hear or read about. I agreed with their points and have not used one since.

Lately, I have noticed some tec divers do (small number) and most don't use AI. Those that do, I have asked some why and how. All the standard replies just lead me to more questions.

Battery failure, some claim your computer will provide a low battery warning for the Xmitter. Great, what happens when it dies during the dive because you failed to notice the warnning on boot up? You're relying on another battery (PDC) to monitor a battery (Xmitter).

Damaged Xmitter. The cleanest 'solution' I have noticed was installing a short HP hose and tying the xmitter to the manifold or onto the first stage where it is not on top. This helps reduces the chances of it being used as a lifting point. Fine, now you have more points were a problem could occur and fewer choices incase of failure. I'm also not convinced having it flexible, were the tie could break and leave it dangling, is any better than having it mounted solid.

When tec diving you have enough things to worry about, making wise (IMO) choices about items such as AI, allows you to reduce the chances. KISS.

 

[cciejames007]

Very good to know and I see where you are all coming from. So, I will work towards that then. Right now I carry at least two methods, one is an Analog Watch with Depth on it, or the D9tx, or now the DG05. Thanks for the advice and new way to try to work out diving.

So I guess too, to answer the original question, the DG05 is an awesome computer and so far I only see the AI, then "IF" you are going to dive with a computer just don't use the AI for tech. I mean, the AI is optional, it doesn't come with it and it can add quite a bit to the price tag.

 

[ianr33]

So far, I haven't seen a reason why not to use the AI.

What will an AI computer make of a sidemount cave dive. Pressure in one tank has not changed for maybe 15 minutes and the 100% O2 (deco gas) is maybe 1/2 mile way having been dropped just inside the entrance??

 

[cbrich]

I want the Liquivision Lynx for my recreational diving only because it's air integrated and OLED. As for Tec diving, I will grab a Shearwater any day of the week. Uemis is a company that is gone; Hollis looks like (possible is) a VR computer.

Liquivision : Scuba : Lynx

If you get into tec diving, you will have a whole new set of gear and toys. CCR is another new set of gear and toys.

 

[cavemn]

I understand this, however the option for non-tech dives would be very nice. do you have any experience with the DG05 or only the Shearwater?

---------- Post added April 4th, 2012 at 11:32 AM ----------

Sorry, I just saw this. I have experience with VR technologies having had VR3s previously. The DG05 is a VRX OLED. IMHO the service took forever and was not favorable. I have two Predators and prefer them over an X1 for user changeable batteries(one less thing to charge), easy to read interface and overall it is a very intuitive computer. Very durable too. I don't exactly treat mine nicely in overhead environments.