Cressi Leonardo- Too conservative?

[lowviz]

I only plan to dive on vacation - carribbean.

Leonardo is fine, nice DC. Be happy with it. One button.

For US$ 50 more you can get the Giotto. Three buttons, a bit more thinking and a lot more options...

 

[Freewillow]

I guess, you have understood that I do not like the Cressi Leonardo

 

[lowviz]

Yes, I understand. But, no offense, that does not make it a bad dive computer (algorithm) for everyone. The variation in human tolerance to bubbling is surprisingly great.

The constant stream of inquiries for a more liberal DC amuses me. I dive a VR3. It is stupidly conservative by recreational standards. Why? Because it quickly promotes the optional safety stop to a mandatory one. After that, it isn't all that different from other ascent profiles but my safety stop becoming mandatory is what knocks me out of the crowd early. No prob, I just do light deco right alongside of those who are doing an optional safety stop.

I like RGBM because it enforces a slow ascent under recreational profiles. IMHO, the biggest problem for recreational divers is a fast final ascent: Been there, done that, saw it, time to get back on the boat!

 

[stuartv]

Yes, I understand. But, no offense, that does not make it a bad dive computer (algorithm) for everyone. The variation in human tolerance to bubbling is surprisingly great.

The constant stream of inquiries for a more liberal DC amuses me. I dive a VR3. It is stupidly conservative by recreational standards. Why? Because it quickly promotes the optional safety stop to a mandatory one.

That is not what would make me classify it as "conservative" or "liberal". It's what the computer tells you your NDL is, particularly on repetitive dives.

To know that, you need data like Scuba Labs published here:

http://www.scubadiving.com/files/old/images/pdf/scubalab_200706_10_new_comps.pdf

(link is from this page: dive computers: scuba gear reviews | Scuba Diving)

Here's another:

http://ads.bonniercorp.com/scuba/PDF/Chamber-illo.pdf

from here: dive computers, scuba gear reviews 2011 | Scuba Diving

And another:

http://ads.bonniercorp.com/scuba/PDF/ScubaLab-Computer-Test-September-2014-data.pdf

from here: SCUBALAB 2014: Dive Computer Review - Page 2 | Scuba Diving

As you can see, different computers allow you different amounts of bottom time, which differences can be fairly significant as the repetitive dives add up.

Unless you think more "liberal" computers (like Oceanic/Aeris, just as an example) computers are unsafe, why would you not want to use one that allows you more bottom time and thus lets YOU decide if you want to be conservative and come up sooner? Most of the Oceanics even allow you to choose a more conservative algorithm and/or set a Conservative Factor, if you want to, so that if you want to dive a more conservative profile and have it enforced on you, you can set it to do so.

Anyway, I'm not sure who you were really addressing, but I have not said at all that the Leonardo is a bad dive computer. I am just pointing out data to help the OP (or anyone else) decide what they want to buy, rather than relying on someone else's judgment of what is "good enough". It's great that you are happy with your VR3, but the insinuation that someone who wants a computer with a more liberal algorithm is somehow inferior ("Ha ha! Look at that idiot. I am so amused.") is not very, well, polite.

 

[lowviz]

...//... As you can see, different computers allow you different amounts of bottom time, which differences can be fairly significant as the repetitive dives add up.

Yes, "fairly" significant. It is up to the diver to assess his/her feeling after aggressive diving. Then he/she alone can make the call for a more or less aggressive computer algorithm. Or use a more aggressive one more conservatively. The point that I didn't seem to make centers on "What should you give a diver who is just starting out and has no experience with the vagaries of dive computers and algorithms?"

...//... Unless you think more "liberal" computers (like Oceanic/Aeris, just as an example) computers are unsafe, why would you not want to use one that allows you more bottom time and thus lets YOU decide if you want to be conservative and come up sooner?

Never, ever said that they are unsafe. However, you imply that anyone should be able factor in the common knowledge that this or that is more or less liberal and then add your own guess as to how do dive it?

...//...the insinuation that someone who wants a computer with a more liberal algorithm is somehow inferior ("Ha ha! Look at that idiot. I am so amused.") is not very, well, polite.

Correct, that would be impolite, never my intention. Uninformed would be a better word than inferior. I'll be more careful with the word "amused". If I really felt that way, I wouldn't bother to post. Just lurk and snicker.

So as a take-away from all this, I'd suggest anyone starting out start by just matching DC's with your dive bud. I don't care what algorithm or DC you pick when starting out as long as it allows you to dive (i.e. nitrox capable if you dive nitrox). Listen to your body and adjust accordingly. When starting out, please police yourself with respect to slow final ascents.

 

[stuartv]

Yes, "fairly" significant. It is up to the diver to assess his/her feeling after aggressive diving. Then he/she alone can make the call for a more or less aggressive computer algorithm. Or use a more aggressive one more conservatively. The point that I didn't seem to make centers on "What should you give a diver who is just starting out and has no experience with the vagaries of dive computers and algorithms?"

Never, ever said that they are unsafe. However, you imply that anyone should be able factor in the common knowledge that this or that is more or less liberal and then add your own guess as to how do dive it?

Correct, that would be impolite, never my intention. Uninformed would be a better word than inferior. I'll be more careful with the word "amused". If I really felt that way, I wouldn't bother to post. Just lurk and snicker.

So as a take-away from all this, I'd suggest anyone starting out start by just matching DC's with your dive bud. I don't care what algorithm or DC you pick when starting out as long as it allows you to dive (i.e. nitrox capable if you dive nitrox). Listen to your body and adjust accordingly. When starting out, please police yourself with respect to slow final ascents.

The OP does not seem to be "just starting out and has no experience". He said he's logged 30 dives and his Leonardo is making him have to cut dives short compared to the people he's been diving with. What criteria does one need to have in order for a quest for a more liberal DC to not be amusing?

 

[Octopusprime]

My Areis 100 Is fine on the bottom timer but the accent speed is very conservative less than 30ft a min puts you in warning. I got locked out with out exceeding 60ft a min on the accent.

My sister and bro in law use the mares puck it is much better than my Areis...

 

[uncfnp]

When discussing the pros and cons of any dive computer there are a number of considerations but perhaps the most important are the features and the underlying algorithm. When someone complains they don't like a certain computer, such as the Cressi Leonardo discussed in this thread, because it is too conservation, they are actually complaining about the algorithm, not the computer itself. I think this might be a point needing clarification for some that might read this thread.

...//...
Unless you think more "liberal" computers (like Oceanic/Aeris, just as an example) computers are unsafe, why would you not want to use one that allows you more bottom time and thus lets YOU decide if you want to be conservative and come up sooner? ...//...

That's an interesting question. So your take is that the most liberal computer (algorithm) is the optimal computer and then it should be up to each diver to arbitrarily decide how to adapt that single algorithm to his/her risk profile?

 

[lowviz]

The OP does not seem to be "just starting out and has no experience". He said he's logged 30 dives and his Leonardo is making him have to cut dives short compared to the people he's been diving with. What criteria does one need to have in order for a quest for a more liberal DC to not be amusing?

I don't doubt that his Leonardo is sending him off the bottom a bit sooner. So the best computer is the one that always lets you be the last one off the bottom? If that is your quest then I find it uninformed. Let's agree to drop the word "amusing".

My Areis 100 Is fine on the bottom timer but the accent speed is very conservative less than 30ft a min puts you in warning. I got locked out with out exceeding 60ft a min on the accent.

You do know that your ascent rate is an integral part of the decompression algorithm? AERIS : Computers

My sister and bro in law use the mares puck it is much better than my Areis...

Again, "much better" means nothing more than more bottom time.

One of the best books ever written for divers trying to understand this stuff has the unfortunate title of "Deco for Divers" by Mark Powell (aquapress). It is a brilliant assimilation and careful re-presentation of a multitude of very confusing concepts. This book pulls it all together in a comprehensible way. I recommend it for the serious NDL diver.

For all others, just find the one DC that will let you always be the very last one back on the boat. If you rash or get bent at a rate that exceeds your comfort level, then you may wish to back off a bit.

 

[stuartv]

I don't doubt that his Leonardo is sending him off the bottom a bit sooner. So the best computer is the one that always lets you be the last one off the bottom? If that is your quest then I find it uninformed. Let's agree to drop the word "amusing".


You do know that your ascent rate is an integral part of the decompression algorithm? AERIS : Computers

Again, "much better" means nothing more than more bottom time.

One of the best books ever written for divers trying to understand this stuff has the unfortunate title of "Deco for Divers" by Mark Powell (aquapress). It is a brilliant assimilation and careful re-presentation of a multitude of very confusing concepts. This book pulls it all together in a comprehensible way. I recommend it for the serious NDL diver.

For all others, just find the one DC that will let you always be the very last one back on the boat. If you rash or get bent at a rate that exceeds your comfort level, then you may wish to back off a bit.

Your two highlighted statements seem to be at odds with each other.

The OP asked if anyone has had similar experiences to his, which are that his Leonardo is cutting his dives short compared to people he's diving with that have other computers. I gave links to reviews of various computers with actual repetitive dive data, that the OP can use to compare how different DCs behave. I've also taken exception to your implication that people who have a computer and want one that is less conservative are *ahem* uninformed. Is there really any more to say on any of that?

My question about why anyone would want to buy a PDC for Rec diving that arbitrarily restricts their bottom time was based on several ideas that I believe are correct: One, all the computers in question are generally accepted as safe (regarding the algorithms they use). Two, all the major manufacturers (of Rec computers) make (Rec) DCs with comparable feature sets. Thus, the implication (by me) that computers with more conservative bottom times are arbitrary - because others with less conservative BT are accepted as safe. And the conclusion that buying a computer that gives longer BTs makes sense because you can get one with whatever features you want and if you can get all the features you want and also get longer bottom times (allowances, anyway), why would you not? Being "down" is why we all do this, right?

Anyway, I'm not actually trying to push any particular computer or brand or algorithm. I'm just trying to promote giving people data and letting them make their own decisions, instead of telling people "I'm a lot more experienced than you and this is good enough for me, so you should accept it as good enough for you." And instead of snarkily deriding people who ask about computers with more liberal algorithms - especially when they have dive experience that has SHOWN them that what they are using is more conservative than what they want.