Computers with non-conservative algorithm.
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Are you expecting the computer would give you an analysis report of your dive and details why it had the NDL it had? If there was one that can do this, you won't be able to pay for it. If you want a theory background on the computer and its RGBM, there are many documents and videos on the Suunto website and on youtube.
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@BurhanMuntasser I don't think I've gone off topic. Here's why.
OP asked for a non-conservative algorithm. What was required information that was not provided was whether he wanted a liberal algorithm for multiple rapid fire dives, or individual long dives. He did not mention what he wanted the computer to be liberal in relation to what he deems conservative. No mention of how liberal he actually wanted to go.
What I pointed out was that without a computer that you get to control the conservatism with a very simple to understand concept *i.e. gradient factors. In NDL diving you basically leave GF-Lo at default and setting the GF-Hi which allows you to choose the percentage of tissue loading that you want to dive with*. That to me gives me information that I want to know other than a proprietary algorithm with conservatism 1,2,3 but they don't actually tell you what those levels mean.
I trust my regulators to provide air, but there is no "magic" going on inside regulators. They are simple machines that provide a very basic function. My BC is a balloon with two valves on it, no magic going on. A decompression algorithm that does what Steve commented on by randomly padding the dive and not telling you why is performing magic that no one can understand because the manufacturer doesn't tell you what it is doing. That is putting blind faith into something that you have absolutely no control over and is the only piece of dive gear that we use that does that.
Regarding your comment about whether the OP asked how computers work. I think that's a bit harsh of a response since in order to understand what makes a conservative computer conservative, you have to understand how they work, don't you?
You want the least conservative computer on the market? Buy anything running a Buhlmann Algorithm that you can set the GF Hi to 99, or a VPM computer at 0 and since safety stops are optional, skip them. You are all but guaranteed to bend yourself running those algorithms in those settings, but there are many computers on the market that will let you do it. These computers do absolutely nothing other than track your tissue loading as accurately as they can. If you sawtooth profile, rapid ascent, short SIT, whatever, they don't care. They give you your actual dive profile in the log and you can see what you actually did. Why does this matter? Your risk of DCS is completely different diving in deep dark water kicking against a current in New England vs. a clear blue water drift dive in the Caribbean and the computers have no way to know what you're doing. As an educated diver, you should understand these changes and be able to adjust your conservatism accordingly.
Computers like Oceanic, Suunto, everyone running proprietary algorithms will randomly add conservatism and not tell you when they did, why they did, or how much they added. Just throw it in there because why not. That doesn't jive with me and I would rather run tables than use those computers, and did for a long time until I could afford a Shearwater.
OP asked for a non-conservative algorithm. What was required information that was not provided was whether he wanted a liberal algorithm for multiple rapid fire dives, or individual long dives. He did not mention what he wanted the computer to be liberal in relation to what he deems conservative. No mention of how liberal he actually wanted to go.
What I pointed out was that without a computer that you get to control the conservatism with a very simple to understand concept *i.e. gradient factors. In NDL diving you basically leave GF-Lo at default and setting the GF-Hi which allows you to choose the percentage of tissue loading that you want to dive with*. That to me gives me information that I want to know other than a proprietary algorithm with conservatism 1,2,3 but they don't actually tell you what those levels mean.
I trust my regulators to provide air, but there is no "magic" going on inside regulators. They are simple machines that provide a very basic function. My BC is a balloon with two valves on it, no magic going on. A decompression algorithm that does what Steve commented on by randomly padding the dive and not telling you why is performing magic that no one can understand because the manufacturer doesn't tell you what it is doing. That is putting blind faith into something that you have absolutely no control over and is the only piece of dive gear that we use that does that.
Regarding your comment about whether the OP asked how computers work. I think that's a bit harsh of a response since in order to understand what makes a conservative computer conservative, you have to understand how they work, don't you?
You want the least conservative computer on the market? Buy anything running a Buhlmann Algorithm that you can set the GF Hi to 99, or a VPM computer at 0 and since safety stops are optional, skip them. You are all but guaranteed to bend yourself running those algorithms in those settings, but there are many computers on the market that will let you do it. These computers do absolutely nothing other than track your tissue loading as accurately as they can. If you sawtooth profile, rapid ascent, short SIT, whatever, they don't care. They give you your actual dive profile in the log and you can see what you actually did. Why does this matter? Your risk of DCS is completely different diving in deep dark water kicking against a current in New England vs. a clear blue water drift dive in the Caribbean and the computers have no way to know what you're doing. As an educated diver, you should understand these changes and be able to adjust your conservatism accordingly.
Computers like Oceanic, Suunto, everyone running proprietary algorithms will randomly add conservatism and not tell you when they did, why they did, or how much they added. Just throw it in there because why not. That doesn't jive with me and I would rather run tables than use those computers, and did for a long time until I could afford a Shearwater.
I agree, Shearwater with gradient factors would be good because you can adjust them depending on the dive and conditions, who you are diving with etc. But most importantly it is not a bubble model programme like Suuntos RGBM which seems to leave you in the water longer than anything else, although of course you can adjust for conservatism on it. Not sure if the rec mode in Shearwater stop you from hurting yourself though, locks you out, beep and farts if you ascend too fast etc. It is really a technical diving computer in the first instance, adapted to the recreational market for obvious reasons. So quite pricey.
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I don't expect the computer to analyze. I would just like to know how typical actions on my part affect things. For example is length of SI a continuous variable or are there critical points. Is 55 min that different from 60 min? Etc.
I just spent 10 minutes on the Sunnto website. Everything I saw was either sales pitches or talked about the technical or new fused algorithm. If you would care to share a link that addresses my specific question - what type of activities incur a penalty and how much of one- I would appreciate it.
Right. But, you know a LOT more than the average recreational diver already. And your base of knowledge allows you to evaluate the info you're talking about in a meaningful way. The average recreational diver does not have the ability to evaluate the info that you're talking about, so it's of no use to him or her. And that means that even getting into that discussion is likely to just confuse them or put them completely off of what you're saying. I mean, seriously, how many recreational divers have the knowledge base to evaluate computers based on whether they're going to do numerous shallow tropical reef dives versus occasional, two-per-day NJ wreck dives? And how many of them even care to be that detailed? I reckon "not many" is the answer to both questions.
People who have the ability to evaluate a computer based on those kinds of things are not likely to come here and ask "I want a computer with a liberal algorithm. What should I look at?"
What is your basis for saying that? The Oceanic computers running DSAT seem to translate very closely to using a GF Hi of 99. I think there are quite a few people using those computers and that algorithm and it doesn't seem like many of them are getting bent.
Would you buy a tech computer that only allows a max GF Hi of 70? Probably not. That is the same reason I would suggest to anyone shopping for a Recreational computer that they at least CONSIDER something that runs DSAT. Because you can run it at a very low level of conservatism (analogous to using GF Hi of 99) or you can change the conservatism to something higher (analogous to GF Hi of 70, for example).
Some of the other recreational computers seem to be roughly equivalent, in concept, to buying a computer with GF that only allows a max GF Hi of 70. That may even sound super safe and a good thing. But, maybe it's not so safe when people start deciding their computer is too conservative so they're going to ignore it and follow what their buddy's computer says....
My work horse has been Uwatec Aladin Pro Nitrox for the last 18yrs. I had added a Oceanic Veo 180 as a back up not too long ago. Both computers have very similar ndl at depth but the Veo 180 allows more dive time as I ascent to the shallow part of the dive.
As far as I am concern, Oceanic on DSAT is too aggressive and PZ+ is probably fine for most divers who are looking for a of bit cushion.
As far as I am concern, Oceanic on DSAT is too aggressive and PZ+ is probably fine for most divers who are looking for a of bit cushion.
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check how the Oceanic follows ZHl/99 for repetitive dives. First dive conservatism is not what most people want which is why almost no one uses the NAUI tables. Back when tables were still taught, good instructors should be explaining the pros and cons of the two "main" tables and when and why to use them. NAUI tables were based off the USN tables where they were optimized for one single long dive per day, hence why there is a 24hr reset period, and the first dive NDL is longer than on the PADI RDP. PADI decided that this type of diving was not what people were doing in the real world so they invested an insane amount of money to develop the RDP where it was designed not around single exposure, but around repetitive diving with short surface intervals.
Oceanic DSAT is basically the PADI RDP, even per Oceanic, i.e. optimized for things like liveaboards, or Caribbean diving. Comparing it to Buhlmann on the first dive is unfair because what they have not told us is how the computer works for repetitive diving. DSAT uses a completely different method to calculation tissue loading than the Buhlmann algorithm they used to make PZ+, but again, we don't know what their conservatism levels mean or what they equate to in a public algorithm. Do I use DSAT even though on the first dive it roughly matches Buhlmann GF99, but on the third dive of the day it's going to GF70 *I have no idea what it actually ends up looking like, was just a random number*. The difference here is on how they choose to track the slow tissues and which tissues they favor. Are they trying to prevent bubbles in the fast tissues but that comes at the expense of the slow tissues still ongassing? *all bubble models, and a Buhlmann algorithm with a low GF Lo which will quickly shorten your repetitive dives but not really impact your first dive*, or do they find a more balanced or slow tissue bias where they try to get you shallow quick in order to minimize on gassing of the slow tissues?
If divers are pushing the NDL's, choosing computers based on an algorithm, choosing their conservatism factors, they NEED to understand how and why the algorithms are doing what they are doing instead of blindly picking some random number and calling it good enough.
Oceanic DSAT is basically the PADI RDP, even per Oceanic, i.e. optimized for things like liveaboards, or Caribbean diving. Comparing it to Buhlmann on the first dive is unfair because what they have not told us is how the computer works for repetitive diving. DSAT uses a completely different method to calculation tissue loading than the Buhlmann algorithm they used to make PZ+, but again, we don't know what their conservatism levels mean or what they equate to in a public algorithm. Do I use DSAT even though on the first dive it roughly matches Buhlmann GF99, but on the third dive of the day it's going to GF70 *I have no idea what it actually ends up looking like, was just a random number*. The difference here is on how they choose to track the slow tissues and which tissues they favor. Are they trying to prevent bubbles in the fast tissues but that comes at the expense of the slow tissues still ongassing? *all bubble models, and a Buhlmann algorithm with a low GF Lo which will quickly shorten your repetitive dives but not really impact your first dive*, or do they find a more balanced or slow tissue bias where they try to get you shallow quick in order to minimize on gassing of the slow tissues?
If divers are pushing the NDL's, choosing computers based on an algorithm, choosing their conservatism factors, they NEED to understand how and why the algorithms are doing what they are doing instead of blindly picking some random number and calling it good enough.
I think that @stuartv have answered you concerning recreational divers and their needs and background. Oceanic has explained in a simple way how the two algorithms differ and where they can/should be used.
Expecting recreational diver, who can't work the tables most of the time, to figure GF, etc. and not be happy with just "conservatism settings" as suggested by computer mfg. is just ridicules.
Expecting recreational diver, who can't work the tables most of the time, to figure GF, etc. and not be happy with just "conservatism settings" as suggested by computer mfg. is just ridicules.
To Original Poster, get yourself an Oceanic. 
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