Register a SA Forums Account here!
JOINING THE SA FORUMS WILL REMOVE THIS BIG AD, THE ANNOYING UNDERLINED ADS, AND STUPID INTERSTITIAL ADS!!!

You can: log in, read the tech support FAQ, or request your lost password. This dumb message (and those ads) will appear on every screen until you register! Get rid of this crap by registering your own SA Forums Account and joining roughly 150,000 Goons, for the one-time price of $9.95! We charge money because it costs us money per month for bills, and since we don't believe in showing ads to our users, we try to make the money back through forum registrations.
 
  • Post
  • Reply
pupdive
Jun 13, 2012


Amazing pictures throughout the thread. For those who have not been diving, an interesting point: Pictures simply do not do it justice. The experience of being weightless underwater is, all by itself, the most amazing thing a human being can do, because it is just so far outside the range of expectation of what humans are capable of that few who do not dive can even begin to understand how cool it is to 'fly' underwater.

Add to that the grace with which underwater creatures move, and it is basically a religious experience every time a diver goes down, except for jaded people who forget to enjoy what life has to offer.

Long-time full-time instructor ready to answer any question also. (I will probably be wrong, because the diving internet is pretty much full of people who know more about diving than people who do it for a living, but.)

Kaal posted:

Guam is noticeably warmer than Hawaiian water (4-5 degrees F warmer). HI is relatively cooler than many tropical areas due to its geographical position. Still, water transfers heat away from you 20 times as quickly as air; so any water temperature less than 98F will cool you down during prolonged immersion.

Actually it is more like anything over roughly 91-94 degrees can often cause overheating with any level of activity, depending on fifty million things. Plenty of people who dive the tropics have trouble only with overheating, while plenty of other people in the same water freeze their butts off.

Adbot
ADBOT LOVES YOU

pupdive
Jun 13, 2012


TANZENTURTLE posted:

Off for another night dive tonight, hopefully ill be able to get some more snaps of something interesting. I know there is supposed to be a number of moray eels where were heading and im hoping theyre reasonably active at night. Happy diving goons.

What got you into night diving?

pupdive
Jun 13, 2012


TANZENTURTLE posted:

I noticed a while back that some people where talking about having done diving in quarries, im guessing because they live in central US states or similar circumstances. Can anyone elaborate what diving in a good quarry site is like? Do they deliberately hatch sustainable ecosystems to make them attractions?

http://www.lochlow-minn.com/

http://dutchsprings.com/

http://www.2dive.com/btm.htm

http://www.sportdiver.com/keywords/bonne-terre-mine/bonne-terre-mine-missouri

Quarry/mine diving is how to train when ocean or lakes are far but they have some advantages, including the fact that as man made things putting in training platforms etc is not problem.

Ocean sites cannot be altered in any way usually, including putting in stairs and the like away from the ocean itself.

pupdive
Jun 13, 2012


Clicktrack posted:

Our next training night-dive is this Thursday. Part of the training is, once descended, to have everyone turn off their torches and just float in total darkness for a couple of minutes. Sounds freaky as hell, can't wait.

Depending on the phase of the moon, and the visibility, it is entirely possible it will not be anywhere close to total darkness.

When teaching night diving, this always turns out to be the student's the favorite part of the dive afterwards. I have done entire dives w/o lights, with no problems getting and receiving hand signals, seeing marine life, and navigating just by the full moon.

pupdive
Jun 13, 2012


Clicktrack posted:

Crazy, until what sort of depth can you usually see without torches in these conditions?

I usually plan night dives to be as shallow as possible 7-10m 20-35 ft.

The no light diving portion of a night dive is interesting: Because the color sensitive light cones in our eyes are concentrated in the front of the eyes and the more light sensitive black and white sensing rods tend to the peripheral vision, you end up not looking straight at stuff to see it best.

http://en.wikipedia.org/wiki/Cone_cell

So one is not always seeing perfectly on one hand. But when the stars line up right (full moon (or nearby bright lighting), 100ft+/30m+ visibility), you can see colors (faded but visible) by the incident light.

http://en.wikipedia.org/wiki/Manta_ray_night_dive

The Manta Ray Night Dive on the Big Island of Hawaii originally came about because one of the hotels put lights in and near the water that drew plankton, and that drew Manta to feed on them. Originally light usage was discouraged to concentrate the plankton around certain areas of the hotel lighting.

Here's something fun to do on a night dive. Leave your light behind pointing up, and swim away from it. You get practice wihout a light, you can always find the light to swim back to, and when you get back to it, a lot of stuff will have been drawn to the light.

For me, PADI no longer requiring a night dive for the advanced class is a mistake. There is so much to learn about everything on a night dive that it is perfect for a training dive, and because it has special procedures it is useful that way too.

pupdive
Jun 13, 2012


Sotore posted:

As an experienced diver, how often do you worry about the 'bends'? And what would you recommend to any novice divers like myself about avoiding it?

Not to avoid answering your question, but as an experienced driver, how often do you worry about getting paralyzed in a car accident?

The metaphor is pretty robust because we can take lots of care to prevent getting bent (always hydrate, stay well away from limits, watch our ascent rates) but we simply cannot be sure it will never happen to us. There are some pretty well accepted risk factors, and yet there are some DCS hits which are completely 'undeserved', to put it one way. Which means we simply do not know all the factors.

I drink 4-5 2 liter bottles of water every day (I dive for work every day) as a preventive measure. But then again I am diving for work every day which is in and of itself a risk factor. Most people I know who have gotten bent have been dive instructors, and dive instructor trainers. I also know some fish collectors who have taken a 'hit', and know of a rather famous case, famous in certain fields that is, of a tourist who did one dive and ended up in the chamber.

Chamber is a hyperbaric Chamber:
(http://en.wikipedia.org/wiki/Diving_chamber#Hyperbaric_chamber)

Only one person I know personally got paralyzed from being bent. On the other hand, I have lost two roommates to death by car accidents, and I still drive without even thinking about that.

About half the people I know who have gotten bent, got bent in Chuuk (Truk Lagoon).
http://en.wikipedia.org/wiki/Chuuk_Lagoon

pupdive fucked around with this message at 11:31 on Aug 27, 2012

pupdive
Jun 13, 2012



What is this a picture of?

(One of the problems with being a long time dive instructor is that I am so used to some stuff, that when a customer points something out to me, I sometimes have no idea what they are noticing with their fresh eyes.

I mean turtles are pretty big, so those are easy. But sometimes I have no idea which new to them thing the customer is noticing.

On the other hand, I was doing an intro dive with some customers and they were enchanted by the fish they were feeding, and out of nowhere a Manta Ray comes swimming by to check us out. And no one but me cared. I was like "Hey look at the manta ray! You might never see one again in your life!" And the customers were like "Forget that Nemo is right here, trying to bite me!" We were both excited, thus the exclamation points.

I do still love playing with bubbles from divers below, which makes me clearly a nerd in some divers eyes. But a lot of the kids I train could spend the entire dive just swimming around in bubbles from other divers below and be happy.


I love this picture. I wish I had shot it myself. I cannot really say what I love about it, but.

pupdive
Jun 13, 2012


Clicktrack posted:

For more experienced night-divers: what kind of behavioral changes do you notice in sea life between day and night dives?

There is almost no way to come to the end of lists of what changes on night dives.

The funniest thing is that there are some schooling fish who just fall to the bottom asleep. They don't find a place to sleep, they just drift to the bottom as a school, and fall asleep still in a vague school shape, with their body color sort of faded out to match the sand. If you poke one, it shakes itself awake, changing colors, and sort of swims half asleep off to somewhere else.

Parrotfish sleep in holes facing out and blow big spit bubbles around themselves which supposedly alerts them in case something comes to hassle them, but usually just alerts divers to their presence.

All the invertebrates come out in force: Crabs, Shrimp, Octopus, and are much more active. Sea Urchins go from being spiky things in holes to being things that are walking around.

If divers ever get a chance to be on a live aboard they should avail themselves of the ability to do a real middle of the night dive. Things change at 9:00 at night, and they change even more by midnight, and even more at 2:30 in the morning. These sorts of dives are easy on a liveaboard, they say.

pupdive
Jun 13, 2012


Crunkjuice posted:

I definitely pee in my drysuit all the time.

(I peed in your suit too!)

I took too many vitamins today, and when I did the post dive flush on the boat, I washed the deck with bright yellow pee.

I am not the slightest bit ashamed to say this.

pupdive
Jun 13, 2012


MA-Horus posted:

I haven't worn a wetsuit yet in Thailand but pee in the ocean erryday.

First dive down to 39.9m today. Highly disconcerting to watch your pressure gauge drop like that. Nitrox/Wreck dives tomorrow.

Nice to see someone actually notice that, and understand why. I sometimes take a tiny 6 CF tank with me to have people breathe from to actually be able to see the needle move.

pupdive
Jun 13, 2012


macado posted:

Anyone have any recommendations for taking the PADI IDC course? I'm looking to take the IDC/IE sometime in late January or February depending on the schedule.

I'm just having trouble finding reviews of different places, the options are endless from Florida, Mexico, Costa Rica, Utila, Roatan, Thailand for places to do it. I thought about doing it in Cozumel since it's one of my favorite places and I frequently dive there and have lots of friends that work on island but I just figured I would also look around at other places. I also looked at Rainbow Divers in the keys.

If you've done the IDC, do you recommend the place where you took it?

My fear is getting stuck in a class with lots of younger students with limited dives. I'm obviously not the most experienced person but I have been diving about 10 years (~850 dives) lots of local diving in New England, wreck/tech diving. I'm not looking for zero-to-hero. I'm already a DM and frequently help OW students in the pool and deckhand/DM on the a dive boat locally.

Not to be confrontational, but the first thing to think about before becoming an instructor is that we really do not need any more instructors who already know everything teaching. We have more than enough of those, and that is the reason why we cannot get octopus's moved to the left side of rental gear, and why we still have tank valves turned back, and why we are still training with snorkels, etc. etc. Because we are tied to the way things used to be, for largely no good reasons other than inertia.

An example of a a word that screams 'already thinks they knows everything' is the word zero-to-hero. I learn something from every single open water student I teach. I have done far, far more diving than anyone I ever teach, and yet I look to students for new ideas, both for my teaching, and for general dive behavior. New ideas come from people new to the field. I want new instructors who are also new divers around me, because at least some of the time they are actually thinking new thoughts. Experienced divers and instructors often tend to get set in their ways. Unfortunately, there are plenty of new divers and instructors who also just parrot what they heard/read and get set in their ways early on without any real experience.

I say that recognizing full well that an instructor's experience is useful. But it is only really useful to those who open to learning from it. And being open to learning from it requires one to be ready to learn from those less knowledgeable about things. Which you do not appear to be ready to do.

Separately:

The IDC is not going to teach anything but how to manipulate the PADI educational system, and course directors are mostly equally good at conveying that info. It would be nice to think that there might be something more in an IDC but since the IDCs are store/resort based nowadays, the something more has just become marketing the store/resort.

pupdive
Jun 13, 2012


MA-Horus posted:

Must it be PADI? I've found SSI puts out some very good instructors.

There is quite simply no reason to become an SSI instructor unless one owns their own dive shop, and does not compete with other dive shops, or the training is free. An SSI instructor can only teach at an assigned SSI location.

It's like getting a driver's license that is only good for cars rented from Hertz. Great for Hertz, bad for the driver. Unless the driver owns a Hertz franchise.

pupdive
Jun 13, 2012


monkeyharness posted:

Hi all,

Nice picks Slicer.

I got my PADI dive certification in 1992, but haven't been diving in years. Just lake dives when I did. My girlfriend wants to get certified, and I wouldn't mind going back through the course as a refresher.
I checked with the local shop where I originally took my certification, and they now offer NAUI.

Are there any major differences between the two?

Nope.

The only difference you might notice is the slightly greater emphasis on 'skin diving', which means using a snorkel. But in the average course you would not really even notice that from the student side.

pupdive
Jun 13, 2012


TLG James posted:

Can you explain the Snorkel thing or the valve thing?

I already know the Snorkel thing is pretty usefull when you are having to swim out to a dropoff and prevents you from getting a mouthful of salt water.

A snorkel is a far less useful than a regulator since it can only be used in one postion (face down, slightly forward) and at one depth (surface). A regulator never gets water in it on the surface, can be used in any orientation, and at any depth. Since the air consumed at the surface is much less than air consumed at depth, the idea that using a snorkel 'saves air' is more a back rationalization of why we are forced by tradition to use snorkels than it is an actual evaluation of appropriate gear choices.

Swimming on the back with scuba is a more efficient way to kick and it lifts the head well clear of the water. It keeps the diver more situationally aware of boat traffic and other surface obstacles, as well as the actual heading. It puts the heavy tank in the water, instead of over the diver.

The usual rationales for requiring snorkels also fall down when one realizes that the very divers who are likely to be stuck at the surface for extended periods (tech divers) almost never wear snorkels because they are a functionless entanglement hazard for most of the dive, and their potential usefulness is just not enough reason to even consider one for most tech divers.

The 'valve thing':
http://scuba.about.com/od/divemedicinesafety/a/Open-Tank-Valves-Fully.htm

pupdive fucked around with this message at 10:50 on Sep 20, 2012

pupdive
Jun 13, 2012


Crunkjuice posted:

you keep octos off the left side because its a big entanglement hazard with your inflator hose and possibly console during an emergency. None of what you said is an actual scuba problem, led alone inhibiting "progress"

So interfering with the inflator hose is a problem, but interfering with your primary gas supply hose is not?

That sounds like one the typical back rationalizations given to explain why thing are rather than an actual attempt to think through gear choices, and setups. I have run a left mounted octo for many years, and never once have I had it interfere with anything but unthought out preconceptions of how to set up gear. In fact having only the primary to the right has made my gear my easier to deal with on many levels, including running a long hose, or an underarm hose.

Please put your octopus on the left side and run through some out of air drills with a buddy. Many who try it once change their setup, once they realize that routing the hose so that an OOA (out of air) diver is not fighting a kinked hose to breathe is a good thing. (Of course some people don't give a drat about their OOA buddy and that's fine too. Only silly people run out of air anyway, I guess.)

It's why BSAC has made left mounted octos standard, and why Japanese have made it a de facto standard. Because approaching gear setup without preconceived notions leads to better ideas about gear setup. Strange to think that Japanese are more open minded about gear setups than Americans, but there it is.

OOA gas sharing either matters, in which the octopus should be on the left for the OOA diver's benefit (or it should be a left running hose, or an Oceanic Omega/Poseidon type), or the octopus is just something we pay lip service too, and we can mount it on the right because it does not matter that is gets pulled out of the OOA divers mouth in an actual gas sharing situation.

pupdive
Jun 13, 2012


QuarkJets posted:

I moved to Maui a few months ago, and I went spear fishing with borrowed gear for the first time two weeks ago, mostly new guys and two experts that we knew. It was pure badass for the entire 8 hours or so that we were out there, and now I want to buy some free diving gear

What's probably the best route for buying gear, just walk into any dive shop or are some places just better? Should I buy any gear online? Is there any gear or gear manufacturer that I should avoid?

Some websites advertise "sports skins" that are supposed to be really thin (1mm or less) wetsuits that are just for UV protection but also provide aerodynamic advantages. If I got one of those instead of a wetsuit, would I get cold during a deep dive in Hawaii?

As above, don't go into a scuba shop and expect much help.

Maui, and really all the Pacific islands, have free-diving shops that know more about what works than any dive shop.

Disagreeing with the above on the open cell suit. Open cell/skinless suits won't last a season.

Thin wetsuits are not good for free-diving for reasons that will become clear as you do it more.

Also disagreeing about the snorkel. Don't necessarily avoid purge valves, just avoid the typical floppy 'scuba' snorkel that dive shops sell. J snorkels are not necessarily the best bet for Hawaii, because sucking sea water sucks.

pupdive
Jun 13, 2012


IM FROM THE FUTURE posted:

I think you are mistaken on the suit style I am referencing or perhaps the language I used. You are thinking of whats called a "chicle" or smooth skin style wetsuit that is unlined exposed neoprene on the outside and inside. These are very common with professional freedivers due to the bare neoprenes smoothness decreasing drag ever so slightly. But as you said, they wouldnt last very long freediving and spearfishing recreationally.

What I am referring to is an outside lined, inside unlined "open cell" "spearfishing" wetsuit. Its the status quo among spearfishing freedivers.

The inside of these suits are open cell and soft neoprene, but the outside is lined with nylon or lycra and is extremely durable. They are made to dive hard in every day and hold up extremely well, usually better then normal scuba suits due to reinforcement of the knees and elbow areas. With my current suit ive done probably 200+ dives over 3 or so years many of which included scraping around on the bottom in holes while spearfishing or lobstering. It still looks and works like new.

Here is the suit I have: http://freedivestore.com/en/wetsuits/67-speardiver-pacific-wetsuit.html There are a number of other brands that make suits in this same style.

Regarding purge valves. A purge valve is absolutely useless if you have used a snorkel more then once. Purgeless snorkels are very easy to clear. A sharp blow expels every drop of water from the top of a non purge snorkel. And it wont keep any more water out then one with a purge. On top of that they can actually be a hazard and often let water in.

The tiny rubber purge diaphragm will eventually fail on you. If this happens during a beach dive or when you are a good distance from your kayak/boat etc you can be in a bit of trouble. If it happens early in the day, your day is shot. This has happened to not only me but a number of friends who got convinced by dive shops a purge was needed. Purge valves blow.

Nope I got what you said about the suit. But one improperly trimmed toenail/thumbnail and you can cut right through an unlined wetsuit. Lined wetsuits last years. Unlined suits last a season. And they are a bitch to get on.

While purge valves can fail, so can diaphragms on scuba first stages, or exhaust valves on second stages. And yet they seem to last years, surprisingly, even under daily usage in rental.

A purge in a snorkel works. If someone wants to have to continually clear the water out of a snorkel in chop, then they do. But a purge makes most clearing unnecessary in chop. If having to continuously clear a snorkel is part of the fun in free-diving then by all means, get a J-Tube.

Of course if all the free-diving is done in perfectly calm water, then a J-Tube is fine there too, because there is no water get in the top of the snorkel at the surface. But the free-diving in Hawaii is not done in pool like conditions, it is done in waves and chop.

Records sound better than CDs. Round masks with metal clamps are the only way to dive. There are people who think J-Tubes are best. But the 'reasoning' is often the same as the reasoning in the previous examples: "drat kids get off my lawn."

pupdive
Jun 13, 2012


DreadLlama posted:

Finally I got back into the water again after a year-long hiatus. Thailand is beautiful and great for diving, but forget about trying to work there.

I'm in Korea now, and holy poo poo, the 38th parallel is much cooler than the 11th. Who knew? The people I dove with were using some newfangled technology called "Semi-dry" suits. It sounds like witchcraft to me. But they were comfortably tech diving at temperatures of about 6 degrees at 40 meters, while I was shivering above the thermocline at 17 degrees at 15 meters.

What's the deal with these semi-dry suits?

Semi-Dry are usually skin-in/Open Cell etc. suits that are unlined to limit the amount of water trapped against the skin. Some go the extra mile and add extended seals like a dry suit. It's the same thing IM FROM THE FUTURE was talking about for free diving, but with extended cuff and neck seals probably.

(It's not anything new. They have been around for many years.)

People who think they need them swear by them. But unfortunately many divers swear by whatever they own. People used to swear by Henderson Polar fleece as well, and said they were as warm as a 3 mil suit. And those suits sucked, and were not much warmer than a rash guard, and not even as warm as a 0.5 neoprene suit, and they lasted not even half a season.

I find open cells do not last long enough to be worth it.

But then again, I work as an instructor for a living, and cannot be bothered with taking more than a few seconds to suit up. I never found the suits much warmer, just more of a pain to put on. It was nice that the inside of the suit was never 'wet' when I first put in on in the morning.

pupdive
Jun 13, 2012


Bishop posted:

Phone posting as I blend my own trimix for a 200 dive today. Get the hell in.

Asking for the sake of asking. Why do you use Trimix for 200' dives?

(I know lots of people use it for anything over 100'. I am just curious about your own reasons.


FWIW, IANTD use to train their run up dives to full Trimix certification on Air to 200'. Obviously, they don't do that no more.



awesome pictures, great composition. Really first class work. This thread has some really great photographers both in composition, and timing. I hope some of the non-divers brwsing the thread bet turned to get wet.


All I can say to those who are waiting to get started: Stop waiting. Even playing with being weightless in a pool is a blast. Add the cool stuff you can actually see and you will kick yourself for waiting.

I came back wet from working the other day and a kid asked me if I had been swimming, and I told him I was a dive instructor, and he just thought it was so cool. And he was right. It is so cool. I took a bunch of divers for an intro dive today, (like I do many days) and it is just a blast watching their eyes get huge as they see fish after fish after fish. And showing them a real life Nemo is just the coolest thing in the world.

pupdive fucked around with this message at 07:29 on Nov 7, 2012

pupdive
Jun 13, 2012


Bishop posted:

First of all gently caress all of you who have seen whale sharks I'm jealous as poo poo
I'll buy the HE for "big" dives, which this was. Mainly because it reduces my deco time because you offgas helium faster than nitrogen. This means I either carry less deco gas or I have more of a surplus. I've never had a huge problem with narcosis (never been deeper than 150' on air though), but on a tough technical dive I'd rather not risk being on air. Anything shallower than 150' and I'll go with nitrox (28% or whatever works)

The dive I phoneposted about that you quote is a good example of why I don't want to be narced at 200ft. Current was horrific and we could not hook the wreck, so we tried a hot drop. At sunset. We missed the wreck and were just messing around in the sand and I hear someone screaming through their rebreather. (peanut gallery: A hot drop is trying to sink as fast as possible towards the wreck with no downline or anything, and with rebreathers you can actually speak muffled words while on the loop)

Here is some more jargon (sorry this is impossible to tell with out jargon) Anyways his unit went HAL9000 on him and it was showing a pp02 of 2.5 on every sensor. He tried a dil flush and it just made poo poo worse. He is screaming at me and gesturing with both hands to ascend real quick. He bails out but is burning through that 40cft bottom mix tank real quick. It's a race to 70 feet, because his other tank had 50% 02 in it. I'm ready to donate my primary but I've also got to launch a surface marker real quick because we're drifting like motherfuckers. I only had one shot at launching a surface marker from 150+ feet because my backup is just a 100' spool and would never make it. Then we gotta worry about stops, etc. I had to remember to switch to the right deco gas (was carrying 50% and 100%) and to tell my computer when I did. Once we got up to 40 ft I shined my primary light directly upwards so it illuminated surface marker, in case the boat had not seen it. Everyone ended up fine, but if I was narced maybe I would have hosed up in those first few minutes.

As a funny aside, I get to my 10 foot stop, slowly reeling my way in perfectly since near the bottom, and I drop the loving reel. It sinks out of sight but is still attached to the surface marker. Once we got on the boat we pulled the reel back, but now I have a 400ft rats nest of line to untangle. I think I'm just gonna buy new line.

Zowee, Heilum certainly helped there.

(buy new line. The Dive Rite orange line worked best for me. Yellow can diappeaar.

pupdive
Jun 13, 2012


eviljelly posted:

imo online stuff is not worth bothering with.

I am going to disgree with this pretty strongly. Online learning for the Open Water course is really the only way to go.

Do the learning at your own pace?

Retain online access for the material for life?

And not have to keep track of a paper book?

Yes, yes, and yes. Plus there is nothing more frustrating than not being in the water when one is in a place where one can dive all day and all night. Spend the dry time (classroom) somewhere where diving is not an option anyway.

pupdive
Jun 13, 2012


Crunkjuice posted:

Is keeping track of a paper book difficult for you?

Almost none of my students have any idea of where their text is a month after the class. What's difficult for my students is what's difficult for them. The person asking about online learning is a potential student, who has no experience with what's what.

I have to keep track of mountains of paperwork.

I also know that people pay baggage fees for extra weight, and books weigh a fair amount.

pupdive
Jun 13, 2012


Trivia posted:

I will certainly concede that point. I'm talking those instances where you want to refresh your memory before a dive, whether it be at your locale or on the plane there.

I got nitrox cert'ed two years ago but I'll be damned if I can remember all the nuances of oxygen partial pressures, for example.

What I'm saying is tht both have advantages/disadvantages (obviously).

Well the biggest point to remember about diving in the modern era is that we simply learn/teach theory to justify dive behavior, and then we can simply forget the theory. As an instructor, I cannot do that. But students should, because there is nothing about the theory that really matters, except in the way it justifies in-water behavior.

I really want students to learn that there is a very good reason for various things (in Nitrox, things like why we track O2 exposure, and why depth limits on Nitrox are no fooling around, actual real, hard limits), and then just act appropriately. All the understanding of theory in the world is pointless if the dive behavior is wrong.

Anyone diving Nitrox should be using a dive computer, and then it simply does not matter if the student can do the math.

pupdive
Jun 13, 2012


Tomberforce posted:

so I'm with PADI but I get the impression that NAUI and BSAC have higher standards, so I'm keen to learn more.

Don't believe the hype.

There are just many times more PADI instructors, so there are many times more bad PADI instructors, because any group of people has some idiots in it, and dive instructors in general are full of hot air and nonsense anyway, so the bad instructors look really, really bad.

If you are studying for DM, the first lesson to learn is that the people that talk the most about agencies are the ones who do all their diving on the internet instead of the water. PADI dominates the market in many/most parts of the world so people who want to put their noses in the air want to say bad things about PADI, but seriously there is almost no difference between agencies when comparing classes directly. (In other words don't compare a PADI Nitrox computer based course with a TDI Advanced Nitrox course, instead compare the PADI Nitrox course with the SDI Nitrox course, and you will find both courses are better in some places and lacking in others, but almost no different in practice.)

pupdive
Jun 13, 2012


Loving Africa Chaps posted:

Get a mask and some fins and rent everything else, it'll be fine

Get a mask, and a wrist mounted dive computer, and let the locals provide the rest.

Don't buy fins, they will lead to excess baggage charges unless you specifically choose them on the basis of size and weight.

A wetsuit is pointless for anyone traveling because you will have the wrong exposure protection for almost anywhere your go. Wetsuits are tuned to the location, and fighting with a 3 mil suit in the tropics (or worse yet a 5 mil suit) makes diving a hassle. And wetsuits tend to get pretty crunchy pretty fast when dragged around in planes because of less than 1 ATM environment, and the fact they tend to be hung in really dry air for long period between uses.

On the other hand, though, do get a lycra rash guard with full sleeves and a hood, though, and some kind of swim trunks that won't end up bunching up under a wetsuit (triathlete supply shops are the best place to find these because triathletes don't have time to fight with bunched up swim trunks under their wetsuits), and board shorts with a zip pocket to go over them.

totalnewbie posted:

I need a mask with prescription lens inserts and I am not so confident I can find a pair before my trip in Feb. How big a risk am I taking if I order a pair online as a last resort? (With fit, etc...) and, while I'm at it, same question with fins.

Don;t buy a mask online, least of all a prescription mask. Call ahead to the destination and make sure they stock them, or better yet have them for rent. Most places do, because seeing is the point of diving.

If you have not tried diving yet, you may be surprised to find how well you can see underwater even without correction, too.

I always have students use a rental prescription mask before they buy it. Fit matters, but so does the fact that for some people the correction makes them far more prone to seasickness underwater. Seasickness underwater is a real issue in many places. I regularly have students puke in the pool just from the new feeling of weightlessness, and for some they are fine until they add the RX mask.

pupdive fucked around with this message at 09:08 on Nov 26, 2012

pupdive
Jun 13, 2012


SlicerDicer posted:

Well I find lots of them to be actually arrogant and unsafe.. I get very worried and it can only be matter of time before somebody gets hurt imo..

It's too late for you then, since you already believe the hype. Hopefully it's not too late for the person who asked the question in the first place.

Diving seems to bring out the know-it-all in many people. One of the reason I prefer to teach Open Water to any other courses, because in OW training I do not have to listen to a stream of half remembered random ideas, like I do from Con-Ed students, none of which have really much of anything to do with actually diving, just with tangential stuff, like whether PADI (NAUI, SDI, TDI, GUE) instructors and arrogant and unsafe, and are likely to be the cause of the end of the world (or just the cause of 'someone gets hurt'.)

I still get to hear random nonsense from random divers who feel the need to share their 'wisdom' with me or my students. Diving seems to offer an opportunity for random, intransigent stances on just about anything except actual diving. Gear setups are a great example. 'The way is should be' is always based on something the 'diver' read on the internet or got from an instructor: "Split fins are bad" is the a good example.

pupdive
Jun 13, 2012


SlicerDicer posted:

Welcome to the world of White Balance, I recently got me the Scubapro Jet Fins. From Japan the white ones I now have a mobile current proof white balance card.


Agreed, awesome shots.

Are the white Jet FIns Japan only? (Do they still make pink ones?)

pupdive
Jun 13, 2012


SlicerDicer posted:

jesus dove a backplate and wing.

I need this bumper sticker.

(I am not a BP&W guy, but that's a great enough line to become one for the purposes of humor.)

pupdive
Jun 13, 2012


rockcity posted:

Yeah, I'm assuming they do it as a precaution. That being said, I just put in 1% lower than what I'm diving so it calculates it by the tables.

What they usually do is do the O2 as if it is higher and the N2 also as if it is higher. To be safe about toxicity, and also deco.

Stop thinking tables and dive computers have anything in common. They work under fairly different principles, and are designed for different purposes.

Trying to out-think your dive computer is probably a bad idea, IMHO. Either trust it or don't, but don't try and rig it by giving it bad info, and expect it to be anything but a wrist ornament.

It's like hanging your dive computer on the hang bar on the way down just so it does not go into deco.

pupdive
Jun 13, 2012


Loving Africa Chaps posted:

Do you have an aversion to buying used? Dive gear depreciates alot.

Buying Dive Computer used can be a bad idea, since closeout new ones are so cheap, and dive computers are pretty sensitive to care, or lack thereof.

pupdive
Jun 13, 2012


Here's the thing you are forgetting:

You have done a basically infinite time dive to surface level depth.

Since no deco theory deals with infinite dive times, there is no theory to deal with it.

So on one hand what you are saying makes sense. On the other, when the plane has to dump all its fuel to land, and comes after you for the fuel cost, saying "it makes sense" won't keep them from suing you.

And then the whole chamber cost thing.

pupdive
Jun 13, 2012


Crunkjuice posted:

Once you get over the "OH gently caress I"M BREATHING UNDERWATER THERES A FISH OH MY GOD" feelings, and you get acclimated, everything sort of falls into place.

I am glad to say I have never gotten over these two things, or the fact that I weigh nothing underwater.

My air consumption, not surprisingly, sucks.

On the other hand, air consumption is also just a thing. Some people use more than others. Going diving with some Japanese people, one becomes convinced that they are simply not breathing sometimes: 3200 PSI to start, 2500 PSI to end on a 30 minute dive to 60 feet is a real head scratcher.

(220 Bar 166 Bar 18 meters depth 11.1 liter tank for those playing along in foreign lands).

pupdive
Jun 13, 2012


Bishop posted:

Also in theory what you described is pretty much in water recompression, which is a terrible idea unless you know what you are doing and have good support but I've used it before. You can surface and know that you are way way short on deco and have a few minutes to gather yourself before descending again.

Here's why it is not even close to in-water recompression. In a chamber, breathing 2.8 ATA PPo2 is standard fare. In the water, that's deadly.

Recompression without insanely high PPo2 is just plain stupid, because it is treating DCS with more nitrogen.. In water compression with insanely high PPo2 is also stupid, because Tox hits in water kill. Tox hits in a chamber are just good clean fun for the chamber driver.

So Sur-D is not even slightly like inwater recompression.

pupdive
Jun 13, 2012


Bishop posted:

Aren't you going to start seizing almost immediately with a 2.8ppo2? I know they do tests and such where they intentionally give you an o2 toxx hit in chambers but is it so common that it's just "good clean fun"? Honest question. That sounds insane to me but then again I'm not a commercial diver.

Also "it's just treating DCS with more nitrogen" dosen't make any sense to me either because I'm "treating DCS" when I'm doing regular in water deco and my ppo2 is usually 1.4-1.6 or whatever. Going back down and getting on an o2 rich mix is no different than switching to one on the way up. (this last point assumes you are asymptomatic, just like the guy running to the chamber is)

Over time I've become convinced that in-water recompression gets a worse reputation than it deserves. For advanced decompression divers, surfacing, getting another o2 bottle or whatever, and going back down is not all that risky if you have proper support and have not developed DCS symptoms. If I misjudge how much deco gas I'm going to need by 10 minutes, I'll absolutely do it if the circumstances are correct. Remember I'm not talking about situations where someone has bolted to the surface and is so bent that their blood is foamy.

E: to clarify a couple things, surfacing and being at 1 atmosphere of pressure is going to make nitrogen bubbles expand, but the same thing is happening when the guy surfaces and runs to a chamber to be recompressed. That's why I compared it to in water recompression.

SlicerDicer posted:

Tell that to Richard Pyle

http://www.daneurope.org/c/document_library/get_file?folderId=13501&name=DLFE-121.pdf

Not that I advocate it but you can bet your rear end if I was bent and far enough from medical... I would do IWR over died.. Its also covered in many of my official govt publications.. There is also data and tables out of Australia for it!! Its sound science to some degree but recreationally its not considered good practice or even viable.


Things:

Re 2.8 PPo2
2.8 PPo2 used to be the excursion depth/PPo2 for Navy o2 rebreathers. It's changed now, but that was actually in water diving. In chambers, 2.8PPo2 is operational standard; it might be less at times but it is best to ride right on that line because bruises heal but DCS does not really do as well for well and truly hosed people who are paralyzed when they enter the chamber.

2.8 PPo2 is 60 foot on 100 o2 (more or less), which is a pretty standard treatment table for full o2 environment chambers. 2.8 PPo2 also the standard test done on inside tenders, and inside tenders run right at that often, especially when cycling through a team of inside tenders who have to minimize their n2 exposure because they are not doing a saturation dive like some of the truly badly off patients are.

There is an enormous difference between preventing bubble formation, and getting rid of bubbles that have already caused paralysis, and other CNS symptoms. If you have DCS, treating it with anything other than 100% o2 is treating DCS with more nitrogen, (or like treating a poisoning victim with more poison etc. etc.) Any additional nitrogen is just simply going to make things worse, because anything that eliminates the maximal o2 window is just misunderstanding decompression, and DCS treatment. It's not pressure, it's the relative PP of the inert gas.

Read the linked file of Richard Pyle and he says exactly that:

Richard Pyle posted:

At least three formal methods of IWR have been published. All of them prescribe breathing 100% oxygen for prolonged periods of time at a depth of 30 feet (9meters), supplied via a full face mask

In other words this is not in water recompression as most people bandy it about, and thus is a ways from what most divers think it is. It is absolutely not going in with a 60% o2 mix, or any kind if Nitrox at all; it is going in with 100 o2 and breathing it in water at a PPo2 of 2.0 with a full face mask. And it often results in seizures. And it works because treating DCS with nitrogen is silly, and the Richard Pyle version of IWR is absolutely not doing that. It is accepting o2 hits as the price of doing business.

It's important to read the point Michael Menudo says in that article:"The solution for the technical community is to expect and plan for DCS and be prepared to deal with it". When you are doing dives far from a chamber then those divers are planning to use IWR. They are not doing it as a last resort, it is simply a planned part of the mission.

(That article was originally published more than 20 years ago, and was published secondarily in AquaCorps. There has to be a newer article to cite on it.)

Regarding gov't publications giving credence to what technical divers should do:

Remember soldiers (and navy divers) have signed up to risk their lives performing their duties. Lots of military divers die diving, just like lots of soldiers die soldiering. Just like the o2 rebreathers used to run to 60 ft excursion depth and the death of some divers was just considered part of the risk of being in the military.

pupdive
Jun 13, 2012


macado posted:

59 minute runtime with (O2 and 50%) versus 63 minute runtime with only O2. For extra 4 minutes, seems like not worth it to carry a second bottle.

I find that carrying one bottle easier especially if it is an 80 which just rides better than a 40 for me.


What's your rig for the 'back gas', assuming you are not running SM (sidemount)?

pupdive
Jun 13, 2012


IM FROM THE FUTURE posted:

That is a great picture to show how blue shift and underwater filming works. Are you filming with the Red for a special reason or just to step up your work?

That's just a great shot period, in fact. Any more like this of what the rest of the photo taking diver looks like?

pupdive
Jun 13, 2012


SlicerDicer posted:

Photos of me? All the photos I show I have taken myself


I mean that shot of what the diver sees and what the camera sees, and all that.


Pictures of UW photographers are rare and useful.

pupdive
Jun 13, 2012


Pufflekins posted:

Nah, it's not anything related to the department, thats just where I am getting my (limited)SCBA knowledge from. I'm hesitant about the mouth regulators because I gag when I get fluoride trays at the dentist.

Basically you need to just get over not wanting to wear a mask.

FullFace mask are a real hazard (for technical reasons) and really only for people who are comfortable diving without a mask at all, who need communication units for a specific task*

As wise people say, diving is not sleeping on a feather bed, rather it is a an entry into a completely different environment which requires that you adapt to it, including wearing a mask, using a mouthpiece and finding ways to not gag.

There is always SeaWalker if you just want to do it once.

If you want to dive, you have to be willing to let go of your previously learned behaviors on many levels.

pupdive
Jun 13, 2012


Ko Samui dive centre training recommendations needed...

Adbot
ADBOT LOVES YOU

pupdive
Jun 13, 2012


QuarkJets posted:

Okay, freediving questions now:

Right now I'm still working on suppressing the panic that I feel at my current record depth while freediving. I'm nowhere near hypoxia, I know that. I know that practice is going to be the easiest way to overcome this. Are there other suggestions for reducing panic levels at depth? Should I take up meditation or other groovy poo poo like that?

I've also figured out that while I'm surfacing I can reinhale some of the air that I had to release into my mask during the dive in order to prevent squeeze. This is a huge help in suppressing panic while I'm surfacing, and I can usually take in several small breaths on my way up. Is this ill-advised? I know that it shouldn't affect whether or not I'd get the bends (since it's all the same initial gulp of oxygen), and even if the air is a little stale I can't imagine it hurting any worse than just continuing to hold my breath

First there are seveal actual places that teach freediving in Hawaii. SInce you are lucky to be where free-diving is actually taught, it's probably worth your time to take some classes from them.

Also, free-diving can result in the bends because it is both dealing with compressed air, and rapid ascents which are the magic ingredients to getting the bends.

http://dsc.discovery.com/news/2008/05/12/whale-evolution-bends.html

http://news.sciencemag.org/sciencenow/2007/12/14-02.html

Whales have some adaptations but we are not diving mammals (even though we do retain the diving mammal reflex).

What is your personal record depth? Go ahead and brag, I am always amazed by free-divers.

  • 1
  • 2
  • 3
  • 4
  • 5
  • Post
  • Reply