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Is Technical Diving Right For You?

  By Joe Ross • February 22, 2014 ,

Technical Diving is a Discipline

Poor Diving Skills

Don’t be this diver!

Like most serious tec divers, I read everything I can get my hands on related to the topic. I comb the Internet looking for anything new that will make my own diving a little safer. Naturally, there’s no shortage of opinion, and I am often stupefied by the things I see or read.

As an example, look at the image to the left. This was on a website promoting a technical diving instruction program. (I censored the image to protect the identity of the diver, lol!) I can’t even count the number of things that are wrong. The equipment is wrong. The deco bottle is clipped in wrong. The deco regulator is stowed wrong, not to mention the octopus and extra hoses hanging off of it. The console, BCD, hose lengths, Air2, suicide clips… virtually everything, WRONG! Dangerously wrong!

Beyond that, he’s holding onto the reef to make up for his obviously poor buoyancy skills. And his trim… The list never ends. The bottom line is he’s simply not ready for technical diving. Without a minimum level of precision, technical diving is just plain dangerous. So, bad example aside, if you are considering moving into tec, here are a few thoughts.

First, honestly assess you diving skills

There’s mystique in technical diving, and the idea of diving deep and claiming the label of “technical diver” is very attractive to some. However, not every diver is cut out for this kind of diving. If you are thinking about moving into tec diving, there are a few things you can do that will make your experience as safe and enjoyable as possible.

It starts with your basic diving skills, so get in the water as often as possible. On your next dive, try the following.

  1. Run through all of the PADI open water dive skills and make certain that you have achieved mastery of all of them.
  2. Although hovering for 1 minute is the standard for PADI Open Water certification, on technical dives, you’ll need to hover at various stop depths for much longer duration. Decompression times well over an hour are not unusual. On your practice dives, pick a depth and hold it for at least 10 minutes. If you vary in depth by more than a foot or so, keep practicing.
  3. Take your mask off. Try reading your gauges without it. Get used to breathing without your mask in cold water. Swim around without it. Try to get to the point where you are as comfortable without your mask as with it. You don’t have to like it, but in the event you find yourself with a deco obligation and no mask, which can happen, surfacing just isn’t an option.
  4. Have your drysuit skills dialed. Long dives are almost always drysuit dives. You should be able to manage your buoyancy with absolute precision, so practice holding depths in midwater. Also, maintaining depth in shallow water is significantly more difficult than in deep water. I like the idea of being in about 30 feet, but not descending below, say, 10 feet, for an hour or more. Try it.
  5. Get into a set of doubles and take a test drive. Diving doubles is not difficult, but it can feel busy and out of control until you get a feel for it. Find a patient buddy and swim around in 10 feet of water until you have a feel for the weight and trim differences diving in doubles presents.

If you find yourself struggling with any of the basic mask and buoyancy skills, do practice dives in shallow water until those fundamental dive skills are second nature. Whether it takes one dive or 100 doesn’t really matter. If you have the basics nailed, your first technical diving course will go much more smoothly.

How often do you dive?

Another consideration when deciding to get into technical diving is how often you dive. There are prerequisites that include a minimum number of dives, Nitrox certification, Deep certification, etc., but also consider how much diving you really do (or will do). If you are a once or twice a year diver, mostly on vacation, the demands of technical diving may make sense to think about.

The issue is technical dives are ceiling dives. In fact, most agencies define technical diving as dives made where a direct ascent to the surface is not possible. This could be a physical barrier as in a cave or wreck, or a ceiling imposed by a decompression obligation. In technical diving, any problems must be dealt with underwater.

A good technical diver practices a lot. We run scenarios, plan dives and repeat skills and drills constantly. This is because we know that failures do happen, and conditions change. Something as simple as isolating cylinders 10 seconds faster (or, at all) can mean the difference between having enough breathing gas to safely reach the surface, or not.

Know your goals

For many of us, long deep dives are exciting. It’s not just the depth but the level of focus and satisfaction that comes with executing dives with precision. But, to make these types of dives safely requires more than earning the certification card. Think about your goals. Why are you considering technical diving?

Your reason is as valid as mine or anyone’s. Just keep in mind that to be safe requires a level of commitment that exceeds that in recreational diving. Tec diving is risky. As technical divers, we subject our bodies to what amounts to experimentation and educated guesses with regard to decompression theory. It is an entirely different mindset compared to recreational diving, and you must accept the risks associated with that.

For those who that are willing to practice and learn continuously, technical diving provides an opportunity to dive where others have never been, and to see things that few of us ever will. If this is you, go for it! Just don’t look like the guy in the picture.

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No Stop vs. No Decompression. Which is correct?

  By Joe Ross • February 13, 2014

Should no-decompression diving be renamed no-stop diving?

No stop vs. no decompression diving

A slow ascent is your deco obligation on recreational dives.

Earlier, I was semi-involved in a discussion about terminology regarding no-decompression diving, or diving within the no decompression limits (NDL) that define sport or recreational diving. I suggested that every dive is a decompression dive. I’m not the first to make that assertion. The theory goes like this.

The pressure gradient encountered by divers when ascending from even relatively shallow depths, and for short durations, is such that there still exists a decompression risk. Although rare, data show that divers have been and continue to get bent even when diving well within the no-decompression limits.

In diving, the no decompression limit (NDL) represents the maximum bottom time for a given depth, that a diver may stay without being required to make explicit decompression stops during ascent.

Safety stops do not represent a deco obligation

Before I go on, the 3 minute safety stop you learned during your open water diver course is not considered a decompression stop because it is not technically mandatory. I’d adds safety to your dives, but is not included as part of the mathematical wizardry used to calculate the no-stop limits. As an example, the PADI Recreational Dive Planner allows a 55 minute bottom time (sea level, salt water, first dive of the day) on a dive made to a depth of 60 feet. Thus, the NDL or no-decompression limit at 60fsw is 55 minutes, regardless of whether the diver makes a safety stop or not.

Back to the topic. The argument is in the terminology. PADI, in the new Open Water Diver course for 2014 has stopped using the term “no decompression limit” in favor of the term “no stop” limit. It has been suggested that describing such a dive as no stop is not only confusing, but inaccurate. I personally side with PADI on this issue.

Just because no stops are required does not mean that no decompression obligation exists

Arguments opposed to the idea that every dive is a decompression dive, included a list of natural occurrences that result in a pressure gradient relative to human tissues. Additional points about the affects of flying were made as well.

However, none of these (with the possible exception of data related to U2 pilots above 70,000 feet altitude) result in a pressure gradient anywhere near that, which even a shallow water diver experiences. Even our diver at 60 feet, does in fact, have a decompression obligation. (Notice I said decompression obligation, and nothing about decompression stops.) It is in the form of a slow ascent rate. Most agencies recommend an ascent rate slower than 60 feet per minute. Further, it is standard among many agencies to recommend an ascent rate of only 30 feet per minute. Regardless, a slow ascent is not optional, specifically for the purpose of decompression.

Remember? Slowly Ascend From Every Dive

60 feet (or 30) per minute is the accepted standard by which divers can reasonably expect to off-gas nitrogen at a rate faster than what would result in bubble formation. In other words, fast ascents can get you bent, even if you are well within the no decompression limits and defined by dive tables.

Therefore, if it is possible to experience decompression sickness (the bends), even on “no decompression” dives, is it accurate to refer to them as “no decompression?” I say, no. These are “no stop” dives, yes, but to be safe, the diver still must undergo sufficient decompression, just in the form of a slow ascent.

As a final case in point, what happens to a diver that bolts to the surface from say, 100 feet? The obvious answer is, he is very likely to experience a DCS (decompression sickness) episode. Why? Because of adequate decompression. Therefore, all dives are decompression dives. Agree or not?

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The Importance of Dive Planning

  By Joe Ross • February 3, 2014 ,

Dive planning

Scuba Diving Sparks Marina, NV

Pre-dive at the Sparks Marina

I recently came across John Chatterton’s blog. You might know him as the host of Deep Sea Detectives. For the last several weeks, I’ve been thinking about dive planning and how to convince my recreational students how valuable it is to follow an established dive plan. Then, I read this post by Chatterton: Accomplished Bad Divers

A student of mine was on a boat charter for three days of diving in the Channel Islands off Southern California. It is an annual trip where a bunch of our instructors, students and customers dive like crazy for three days. He was diving in a group that included two instructors and a “fairly experienced” dive master.

Agree on your hand signals before the dive

The foursome jumped into the water and started swimming around a small island. As the dive progressed, the student watched his tank pressure drop at the same time as the group was swimming further and further from the boat. He gave a “half tank” signal resembling a karate chop into his opposite palm. The group kept swimming.

Eventually, he got to a point where he needed to surface—somewhere around 700psi. His “buddies” were beyond a range where he could get their attention so he surfaced alone with enough air, in his view, to support his swim back to the boat if the conditions were choppy. And, they were. Worse, he surfaced fairly close to a rocky wall and was taking a beating from the combined forces of the surge, chop and back-swell bouncing off the wall.

Honestly assess you experience level

Although a good diver, this student is a relatively new diver with about 80 dives to his credit. He holds a PADI Master Scuba Diver rating. Until this particular dive, all his dives had taken place in relatively calm conditions.

Upon surfacing, he found himself in an environment he had not experienced before. Water was beating him over the head, reflecting off the wall, and beating him in the head again. He felt heavy, tired, and, I’m guessing, scared. He also neglected to inflate his BC. Eventually, the other divers surfaced, and one of the instructors asked, “did you inflate your BCD?” He recalls telling him he had, but in reality, he hadn’t.

Not long after, they got him positively buoyant, and assisted him safely back to the boat.

When we talked about it, he was very candid about the idea that he could be a “Master Diver” and still have gotten into a situation like that. It goes without saying that titles are not a replacement for experience. This is why we tell students to dive in conditions they are familiar with.

I often tell people that, in diving, everything is fine, until it’s not. This is an example of that idea.

That’s where experience comes in. Sometimes, it is impossible to avoid a bad situation. Tides change, surf comes up, things break and people do stupid things. It’s easy to be lulled into believing that all dives are the same when all of your dives up to a certain date have been the same.

After our discussion I asked him to reflect on all the diving that took place during that trip. Did you plan those dives? Did everyone on the buddy team know what that plan was? Did you stick to the plan? Was there any contingency planning? Did you go over hand signals?

In reality, no one on the boat was doing any real planning, which is unfortunately, typical. If they had, his buddies would have understood his karate chop “half tank” signal. Ideally, they’d have decided on a turn pressure and stuck to it. And, they would have agreed about the navigation.

Of all the lessons we can learn to make us better divers, planning is too often overlooked. Divers tend to just start swimming.

I think this is the connection to Mr. Chatterton’s blog post. He uses the term “accomplished bad diver” to describe the now dead, Ed. Ed’s fatal flaw was that he refused to learn. The fact that he could keep it together 200 feet down, long enough to find someone with an available gas supply is amazing to me. The fact that the experience wasn’t disturbing enough to make him re-learn the fundamentals of gas management, is shocking.

Stick to your dive plan

Hurricane Bay, Lake Tahoe Scuba Diving

Scuba Diving Hurricane Bay, Lake Tahoe

About a month ago I made a dive with the guy I mentioned earlier, along with another instructor. It was just a fun dive to around 105 feet (Lake Tahoe, so 6228 feet altitude) where we planned to descend to 100 feet on a steep slope, then hang a left remaining at that depth until we’d get to about a 100 year old truck chassis that was converted to a log carrier back when clear cutting was still going on in the Tahoe basin.

We all knew the dive site well, but none of us had ever dived that particular artifact. Consequently, we made our descent probably a hundred feet south of it, leaving me with only 2 minutes of NDL by the time we reached the “wreck.”

I was diving with my Shearwater Petrel dive computer, with the gradient factor set very conservatively. My dive buddies each had 8 or 9 minutes of no decompression time remaining, compared to my 2. And, both were actually below me by a few feet throughout most of the dive. The difference was my very conservative GF.

I’m a technical diver. On this dive, I was in full technical dive gear (to practice shut down drills, etc.). I had full doubles, redundant regulators, isolator bar, plate, dual bladder wing, dry suit, a deco bottle full of 40% Nitrox, a backup timer/tables and a lift bag and reel. I was 100% equipped and trained to stay on the bottom as long as they could and simply hang for 6 or 7 minutes on the way up. But, I didn’t. We began our ascent 2 minutes after reaching the truck.

Be a dive planning role model

We tell students to plan their dives and stick to that plan. To me, that means anytime things deviate form that plan, either the dive ends while the situation is still relatively safe –or– the team moves into safer water (shallower, more sheltered, etc.). We planned that dive very carefully as a computer profile, no-decompression dive. Sticking to the plan means you don’t change it, especially with a big decision that could potentially impact the group, like going from non-deco to deco.

Afterward we talked about the dive and the reason for the short stay on the bottom. No one was upset about it. It was a great dive. But, I wanted to express my opinion that discipline is a critical part of safe diving, no matter how great the dive, or how easy it would’ve been to extend it.

Too often dive students see their instructors bend the rules they teach. Topping that list is dive planning. For starters, when every diver agrees to a plan, it is much easier to recognize a problem and take corrective action before the problem elevates into a full blown crisis. For example, when every member of the dive team agrees to 105 foot maximum depth, but one diver descends to 115, that should throw up a red flag with the rest of the divers. Whereas, had no explicit floor been established, an extra 10 feet may seem normal. Dive plans highlight deviations, which can mean the difference between a problem being recognized early, or one that erodes into something much more serious. Put simply, disciplined divers are safer divers in general because there are fewer surprises.

That’s what dead Ed in the article never learned. He had no business attempting recreational dives, let alone deep, technical dives. He simply didn’t have the discipline. In the end, it got him killed.

 

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Dry Suit Inflation System Mounting

  By Joe Ross • January 27, 2014 ,

Dry suit inflation

Diving in Hurricane Bay, Lake Tahoe

Diving Hurricane Bay

Whether using air or argon, for most dives, I prefer not to use my back gas to inflate my dry suit. Using helium mixes, it’s not optional, but even on air, it often makes sense to use a separate dry suit inflation system.

For example, earlier today, I did a simple dive to 133 feet in Hurricane Bay, Lake Tahoe. The water temperature was relatively warm for this time of year at 43 degrees. But, 43 degrees is still cold water, and while breathing, if I simultaneously inflate my wing and dry suit, there is a much greater chance of free flow than if I’m only inflating one or the other. For the same reason, we often run our wing off the left post around here. DIR guys get their panties in a wad over that one, but inviting a free flowing regulator is definitely not “doing it right” in my book.

Mounting Drysuit Inflation System

Mounting Drysuit Inflation System

Anyway, here’s how I mount my dry suit inflation bottle. I like this better than the webbing/bungee thing I see posted all over the Internet. I also like that I can reach all the components with my left hand if I need to, as opposed to mounting it to one of my back cylinders. Basically, all I’m doing is using a couple hose clamps and tacos to mount bolt snaps to the cylinder and clipping them to my back plate. I like this arrangement because it pushes the tank a little farther out from the plate, making things not quite so cramped around my waste d-ring, and also not too bulky behind my left shoulder.

Mounting the system this way allows me to use either an AL13 or steel 15 and still keep then within reach, without feeling like I have a tennis ball can shoved behind my back.

As a side note, I use a Poseidon high performance first stage for dry suit inflation. I find that down deep, it makes a huge difference in flow, especially a high density gas like argon.

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Logging Your Dives Online – 3 Top Dive Logging Websites

  By Joe Ross • August 12, 2013 ,
divelogs.de Dive Profile From Imported Dive Computer Data

divelogs.de Dive Profile From Imported Dive Computer Data

In the early days of dive computers, uploading dive data to a personal computer wasn’t even on the radar. My first dive computer was an Oceanic Datamax Sport, a solid computer that was compact, easy to read and simple to operate. It would store quite a few dives, but didn’t provide a means for exporting them. After literally decades of logging my dives in paper logbooks (almost 3,500 dives, in fact), I finally bought a SubGear XP10, which made it possible to upload dives to a PC.

The problem is SubGear’s Dive.Log software is PC only, and despite claims made by the manufacturer, a Mac (Linux would be unthinkable) version appears so far down the horizon, I gave up wishing for it ages ago. I’ve been keeping around a netbook running Windows XP just for logging dives and generating decompression tables with GAP. (See: Moving Your Logbook from PC to Mac)

That issue resolved, I’ve taken a great interest in logging dives online. First, I just think it is fun to be able to share dive profiles, dive site and location information and notes about equipment, conditions, sightings, etc. with divers from around the world. More significantly, it forces dive computer manufacturers to conform to standards or risk being displaced by computers that make it easy to upload data to any platform their customers wish.

I’ll focus on what I think are the three best online dive logging websites: divelogs.de, PADI ScubaEarth and DiveBoard. I maintain profiles on all three, so I’m not advocating for any one of these to the exclusion of the others. Rather, my hope is to encourage as many divers as I can reach to share their experiences online and help build all of these into thriving online communities.

divelogs.de

Divelogs.de is a website that has been online for quite a few years and is clearly the most refined of the dive logging websites I’m profiling here. I learned about divelogs.de when exploring the capabilities of SubSurface, a multi-platform desktop program for logging dives, developed by Linus Torvalds, the developer of the Linux operating system. (More on SubSurface later…)

divelogs.de Home Screen

divelogs.de Home Screen

At first glance, divelogs.de looks like a project developed by engineers, which makes sense, because it is. All the functions are there. The menus make sense and the site is fast. Divelogs.de is also capable of importing dive data from just about anything. If you visit my profile, most of the dives that have actual profile data, were logged with the SubGear XP10. My most recent dives, however, were made with the Shearwater Petrel. Both live harmoniously at divelogs.de.

Access your dive logs from anything

The whole point of logging dives is to document your diving experience and to be able to recall information like weighting and exposure protection, environmental conditions, dive site information, etc. While dive computer manufacturers appear to be making incremental moves toward standardization, most are still proprietary. So, you buy a dive computer from brand X, load brand X’s software into your computer and live with it. Thanks to divelogs.de, changing dive computers is a snap.

Divelogs.de provides an awesome range of export options. Here’s the current list:

  • PDF
  • eBook with or without images from your dives
  • Google Earth
  • Excel
  • UDCF
  • DLD which is divelogs’ own format containing much more data than UDCF (Thanks Rainer for the tip!)

Your diving log book as an eBook

If you’re like about a zillion people, including me, your iPad or iPhone is a constant companion. Thanks to diveloge.de, you can now export your logbook into the epub format in the form of an electronic book. For travel, this means you can skip the paper logbook and demonstrate your experience like you would any other book. Between that, and PADI’s eCard, you really don’t have to carry anything else with you.

Dive Logs in iBooks

Your Dive Logs as an eBook

There may be a few dive operators out there who aren’t quite tuned in with the digital age, so taking along your cards and paper dive log may still be a good idea, but I personally haven’t had any issues. (I also haven’t been anywhere very exotic for quite some time.)

I have to admit, part of the appeal of having my logbook in the form of an eBook is the cool factor. Flipping through pages of logged dives in iBooks, everyone wants to know how I get them there. The truth is I just click a button.

Map your dives

divelogs.de Dive Site Google Map

divelogs.de Dive Site Google Map

Another cool feature is the ability to map your dives. Stored with your other dive information, divelogs saves GPS data if you choose to include it. By location, once you have identified a dive site, every time you log a dive made at the same location, that information will be reflected automatically. This is not a feature exclusive to divelogs, but it is cool nonetheless.

What I believe is unique to divelogs.de is the ability to export dives to Google Earth. Next time I run a trip, I am excited to be able to hop from dive site to dive site using Google Earth to orient divers to what they can expect on arrival to each location. Once I have a chance to try this in front of a real group of divers, I’ll be sure to post a followup.

divelogs.de Export to Google Earth

divelogs.de Export to Google Earth

Other features of divelogs.de

If you haven’t guessed by now, I am a huge fan of divelogs. While it doesn’t share the high-end, polished look of the others, it is far and away more advanced in terms of function and integration.

I particularly like that it wasn’t developed commercially–at least not to my knowledge. Divelogs.de is a program created by divers, for divers and it simply works. And, since the site is developed and maintained by divers, as technologies and needs evolve, so does divelogs.de. As a side note, that’s one of the key reasons SubSurface is so powerful, but that’s a topic for another article…

Diveboard

diveboard.com - Diver Certifications

Diveboard profile page showing certifications.

Diveboard was the first online dive community that I personally was impressed with enough to create a profile. I still like it. Some of the key features include dive logging (of course), mapping of dives, storing your certifications, diver to diver messaging, and photo galleries.

I like the way all of these features function, and love the look and feel of the site. In practice, I don’t find myself actively using Diveboard like I do divelogs.de. Primarily this is because Diveboard isn’t nearly as sophisticated in it’s ability to import dives.

A quick look at my Diveboard profile shows a fairly sizable collection of dives, but they lack all of the important details about location, etc. The same exact file imported into divelogs included all of that information. Diveboard also breaks on import if the planets don’t line up just right. So, while I like Diveboard a lot, and applaud the developers for doing a great job, the simple fact that I must manually edit individual dives makes it too time consuming to be practical if you have a lot of dives to add information to.

diveboard.com - Dive Profile View

diveboard.com – Dive Profile View

Once entered, Diveboard’s dive profiles look beautiful. There are plenty of options for adding detail about individual dives and various locations, etc. I should mention with all of these websites divers have the option of keeping their information private, visible only to “buddies” or public.

One thing I really like about Diveboard is it’s “Community.” Basically, it is a blog but has quite a following among active contributors. Topics range from preventing regulator free flows to becoming a dive instructor.

There’s also a gallery, where members can post photos or browse those that have been posted by others divers. Many are spectacular, and as the community grows, Diveboard is sure to add functionality. My guess is, eventually, Diveboard will provide better support for expanded import/export options, as well as many new features even they haven’t thought of yet.

PADI ScubaEarth

PADI Scuba Earth

PADI Scuba Earth

First, I can’t emphasize enough that PADI ScubaEarth is in beta. As a PADI instructor, I am included in their surveys and have a bit of insight as to what’s to come with ScubaEarth. As new features roll out, I’ll be sure to include them. In the mean time, I’ll give my opinion about the site in it’s current beta state without being too critical.

The idea behind ScubaEarth is to create a global community of divers, resorts, PADI dive centers and related organizations. It is a huge undertaking and PADI is uniquely equipped to make it work. As the top certifying agency, PADI has incredible global reach, not only among certified divers, but with every manufacturer, retailer, independent instructor and others.

Basic features of membership to ScubaEarth include logging dives, a growing community of members, messaging, personal galleries and a “dive locker” for storing details about your equipment. That could be very handy in the event of loss or theft.

ScubaEarth also provides tons of great editorial content like featured dive destinations. It makes sense since PADI publishes popular dive magazines in addition to countless publications like books, videos, slates, marketing materials and who knows what else.

PADI Scuba Earth Featured Destinations

PADI Scuba Earth Featured Destinations

Site wide, ScubaEarth provides information about dive stores and resorts worldwide, along with a very Facebook-like “wall.” All of this is very cool and done in the uber-branded, high-end way PADI is famous for.

If ScubaEarth has a weak link, dive logging is it. At present, dives can only be logged manually, so visual profiles are out of the question. One thing that’s nice is that you can search for a dive site and, if that site has been logged previously, location details will be provided.

But, that doesn’t change the fact that dives must be logged one at a time, and for those with lots of dives, it can take hours or days to plug in all the details. I have it on good authority that PADI is looking into options, but I have no way of telling if direct data import is in the works or not. One thing’s for sure. PADI will do whatever it takes to make ScubaEarth the powerful, popular platform it invisions.

Final thoughts…

First, I’d like to restate my appreciation for the developers of each of these for having the vision and commitment to bring such great websites to the diving community. If you haven’t already, I recommend you get online and create an account with all three of these websites, if for no other reason than locking up your favorite screen name.

I’m sure you’ll find features in each that are worth exploring, and the more members each site has, the more motivated they’ll be to add features and increase compatibility.

For me, the favorite, running away, is divelogs.de. I only discovered the site recently and instantly it’s become part of my standard dive logging routine to upload dives (automatically from SubSurface, incidentally) to the site. At the same time I log dives, I create a new eBook and save it to my iPad. It’s all effortless, with seamless ease of use that makes it feel more like a desktop application.

Give them all a try and please send me your comments, and let me know about others I may not be aware of.  I’ll look forward to profiling those too.

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Moving your dive logbook from PC to Mac

  By Joe Ross • July 25, 2013 , , ,

Sort out dive log computer compatibility problems and getting your old dive computer data into your new software.

Divelogs.de screenshot

Divelogs.de screenshot

Tell me if this sounds familiar. You’ve been using a particular dive computer for quite a while, and have hundreds, if not thousands of dives logged using the software it came with. Now, you’ve decided to move from a PC to Mac, and need to find some way to move all your logged dives from PC to Mac, but the dive computer manufacturer doesn’t have a Mac version of its software, and they make matters worse by locking you into some proprietary logbook format.

Well, that’s exactly what I’ve been dealing with for the last couple years. In fact, I’ve kept a netbook around, running Windows XP for about 5 years now, simply because it was all I had to get dives out of my (recentyly dead) Subgear XP10 dive computer. All of my computers run either Linux or Mac OS X, yet I’ve been forced to keep this one little machine running Windows for exactly two programs; Subgear’s Dive.Log and GAP for generating decompression tables. I don’t yet have a solution for GAP, but I’m working on getting it to run under Wine on the Mac. However, after much frustration, I have finally managed to get all of my dive computer data out of SubGear’s Dive.Log and into a dive logging program that is compatible with Mac OS X.

The Dive Computer Challenge

In my case, I made a move away from my old SubGear dive computer for good, replacing it with a Shearwater Petrel. That means I don’t have a need to import dive data directly from the XP10 into the Mac. I simply wanted the dives out of the Subgear, and into whatever software I’d use moving forward.

The Shearwater Petrel syncs through Bluetooth and the company supplies dive logging software that is already Mac compatible. You’d think simply exporting dives from one and importing into the other would be a piece of cake, but not so as neither would support a format that is common to the other.

Dive Log Formats

If you’re lucky, your dive computer software will support exporting into a more or less universal format. Examples are DAN DL7 or DL1, UDCF or Excel file like CSV. The issue I had is that Shearwater Desktop (Shearwater’s name for its dive logging program) wouldn’t import any of those. Just getting Dive.Log to export was no picnic.

So, I turned to diveboard.com, where I’d created an account some months back. DiveBoard has the ability to import DAN and UDCF files, along with a few others. It’s pretty cool (here’s my profile: http://www.diveboard.com/joescuba), but I haven’t taken the time to really engage with it. The problem I had was DiveBoard wouldn’t import my Dive.Log files correctly. Either they’d bomb out as corrupted, or not work for some other reason.

I knew I was on the right track, but needed a magic bullet. The problem really was with Subgear. The simple fact is Dive.Log is not fully tested, and it is clearly not being actively updated. Back to the drawing board…

Thank you Linus Torvalds!

That magic bullet came in the form of a clue inadvertently provided by Linux creator, Linus Torvalds. Linus, it turns out, is an avid scuba diver. As such, he’s taken a natural interest in dive computers and related software, especially related to Open Source and compatibility with the Linux operating system.

He’s developed a program called Subsurface that is compatible with a few additional dive log formats but still wouldn’t directly import (at least not as complete files) anything generated using Dive.Log. However, under the file menu, there is a link labeled “Upload to divelogs.de…”

I ignored that link for my first several attempts at importing data. Frustrated, I decided to stop trying and just poke around in Subsurface a bit. It imported my dives from the Shearwater Petrel without a hiccup, and is really a more robust program than Shearwater Desktop, so I was already planning to use it as my primary logging program–especially since it will run on Linux, which is my preferred OS anyway.

Having dug through about everything that Subsurface has to offer, I decided to see what divelogs.de is all about. Turns out, it’s a bit like DiveBoard, although not as pretty. I figured if divelogs.de is good enough for Linus to put in Subsurface’s menu, it’s good enough for me to create an account (visit my profile page here: https://en.divelogs.de/log/joescuba).

The aha moment!

Naturally, now that I was a proud divelogs.de member, the next step was to see exactly how one goes about uploading his or her dives to the site. And, there it was… shining like a beacon on a dark, foggy night. Under a link labeled “Import logbook,” they list a fairly exhaustive collection of supported formats, and glistening near the bottom of that list is “Subgear Dive.Log.” In my joy, I believe I wept a little.

My native Dive.Log file imported flawlessly, with individual dive profiles completely intact and all the supporting data right where it belonged. BUT, I still needed to get the dives into Subsurface and/or Shearwater Desktop. As it stands, I’m half way there. From divelogs.de, I was able to export a UDCF file that Subsurface imported easily.

Platform independent dive computer

It took a couple days of screwing around but the bottom line is I now have fully platform independent dive logging program that supports my complex technical dive profiles stored in the Shearwater Petrel AND has the dives stored that had been previously locked away in an obsolete netbook, running an obsolete operating system.

There are MANY uber-cool things to love about divelogs.de, as well as Subsurface, so I’ll profile both independently when I get a chance. In the mean time, I’ll bask in newfound glee as I upload dive profiles with reckless abandon.

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Shearwater Petrel Dive Computer

  By Joe Ross • July 23, 2013 , ,

Review of the Shearwater Petrel Dive Computer

Shearwater Petrel Dive Computer

Shearwater Petrel Dive Computer

I’ve owned and used a number of dive computers over the years. The most recent of these was the Subgear XP10, I bought a couple years ago as a simple Nitrox computer for sport dives. Before that, I had an old Oceanic Datamax Sport for that type of diving.

For technical diving, I’d been using an old VR3, and occasionally a Vytec. The VR3 was great for it’s day, but the software always sucked, and the way they lock them at the factory blows. The Vytec never really was a full-fledged technical decompression diving computer in my view, even though it does support gas switches.

Since my XP10 crapped out on me, and none of my computers were really ideal for the range of diving do anyway, I knew it was time for a switch, but was on the fence about what computer to switch to. As a side note, for the last 18 months or so, I’ve doing all my technical dives on tables generated using GAP decompression software. My primary timing device/depth gauge has been the Scubapro Digital 330m Depth Gauge backed up with any other dive computer in gauge mode.

Shearwater Petrel

I had been looking at the Shearwater Petrel since it came out last year. Prior to that, I had planned to buy the Shearwater Predator. I hadn’t made the leap because my deep dives have been more like exercises in precise time and depth management than sightseeing anyway. Even with the computer, I plan very strictly based on the tables I generate using GAP.

But, being an instructor, I do tons of NDL dives using simple computer profiles, as well as lots of sport dives in general. I basically had it with all of my crappy old computers, and when my Subgear XP10 wouldn’t turn on last week, that was it.

The Shearwater Petrel is a technical decompression diving computer in the truest sense. The diver has full control over gradient factors, a choice of decompression algorithms (standard is Bühlmann ZHL-16C), support for 5 breathing gases, customizable views, and of course, out of the box support for closed circuit diving.

So far, I have only made a couple shallow dives with the Shearwater Petrel during an altitude diving course I conducted over the weekend at Lake Tahoe. So, all I can offer at this point is a series of first impressions. The long and short of it is that the Shearwater Petrel is the most intuitive dive computer I have ever used. Here is a list of a few things I love about it:

  • Easy to read with the ability to customize views for the needs of different types of dives
  • Constantly visible PPO2 display
  • Compact for the type of computer it is
  • Bright, easy to read display
  • Simple menus with hints
  • Uses cheap AA battery
  • Bluetooth dive log uploads
  • Mac compatible

My initial dives with the Petral have been no-deco dives, but the view is pretty obvious about what’s happening during the dive whether you have a ceiling or not. Basically, the bottom row of the screen shows your NDL or the depth/duration of your next required stop, plus minimum time required to reach the surface. I should probably note that I am diving open circuit.

The computer also displays your current gas. Changing gases is done by pressing the left button and toggling to your selected gas. Press the right button to make the switch. Gas switching on some computers in miserable. The Vytec is one of them.

The main thing I like about the Shearwater Petrel is that everything you do with it is contextual. If you need to change gases, that process has been made as simple as possible based on where you are in the menu system. Diving in general, all the critical details are available at a glance, yet if you need more detail, it is almost always a single right button press away.

I will, of course, form a more comprehensive opinion once I’ve had a chance to really dive with the Petrel. But, I think, having been in the water with it for a couple repetitive dives, I have a good sense of how it will perform in more demanding circumstances. So far, the Shearwater Petrel is the best computer I’ve ever dived with. It is easy to read and comprehend, as well as easy to use underwater.

Being fully customizable, there’s nothing I find that makes me question it’s suitability for serious technical diving. I’ll follow up with more detail once I’ve had a chance to do some deco dives with it.

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Mounting a GoPro Camera to Scuba Gear

  By Joe Ross • December 17, 2012 , ,

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Mounting a GoPro to Scuba Gear

recently got my hands on a GoPro Hero video camera. I honestly never gave GoPro much thought since I am in the media business and use a lot of high end video gear all the time. Underwater, I’ve been shooting with a slightly outdated Sony HD camera in a Light & Motion housing and a pair of mounted video lights for a long time. It’s compact for what it is, but I set a goal recently to be able to travel without carrying any of that, including my MacBook, and just shoot and edit with a little camera and an iPad.

Even with the other camera, the GoPro has made quite a mark as a cheap and virtually indestructible POV cam. After purchasing the GoPro, I did a little research and learned that the Hero 2 shoots blurry video underwater because of some kind issue with the dome port on the standard housing.

Fortunately, the solution is a $40 replacement housing from GoPro that has a flat port instead of the dome. So far, I haven’t shot anything underwater with either of them, so the only comparisons I have are from YouTube, but that’s not the point of this post anyway.

I have been struggling for a while over how I could mount the camera without interfering with my mask or other equipment. I want to shoot hands-free, and be able to create time lapse sequences of entire dives. So, here’s what I came up with.

Using the GoPro’s handlebar mount, I’m able to attach the camera directly to the valve of my old school 3500 psi Genesis 100 scuba tank. This is actually a second generation valve. Unlike the original, it is configured to attach an H-valve or isolator bar, and the extension provides the perfect attachment point to mount the GoPro. And, I can reach it, so I can turn it on at the beginning of the dive and not have to shoot a bunch of video of the sky prior to descending. That’s the theory anyway.

Mounting the GoPro camera to a set of doubles

Doubles are a little different setup. Well, actually it’s the same setup, but a different concern. For technical dives, I love the idea of shooting the entire dive from the diver’s perspective. I’m not sure if it’ll be all that cool shooting dives with the back of my head always in the frame, but that’s something I’ll deal with later.

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Mounting the GoPro to my doubles isolator bar works just fine, and I can reach it. However, the thumbscrews could potentially impede my ability to control the isolator valve, which is not something I’m willing to risk on a ceiling dive. I’ll try it in shallow water and see if its a problem. My guess, just by looking at it, is yes.

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Plan B will be to replace the thumbscrews with stainless hex head screws cut to exactly the right size. That will get the GoPro mount completely clear of the isolator knob. I could also use a remote isolator knob, but that means more crap on my chest, and I’m not accustomed to that setup anyway.

The pictures aren’t great but you get the idea. In a week or so, I’ll get underwater finally to see how it all works out. In the mean time, if you have experience with this arrangement or something similar, I’d like to know how it’s working.

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PADI Altitude, Drysuit and Enriched Air Specialties

  By Joe Ross • June 22, 2012 ,

Scuba diving specialty certifications every mountain diver should have.

PADI Specialty Course

PADI Specialty Courses

As much as we all love to get into the deep blue, warm water of the tropics, for most of us the majority of our diving takes place near where we live. I feel lucky in that great diving is close by. Lake Tahoe is just 45 minutes up the hill, with Donner Lake and others also nearby.

Ocean diving in places like Monterey Bay can be reached in half a day. What all of these sites have in common is cold water. The rest take place at altitudes typically greater than 4,000 feet. With this in mind, three PADI specialty courses make sense for diver in areas like ours.

PADI Altitude Specialty Course

The thing about diving at altitude is that while air is compressible, water is not. In essence, this means there is a reduction in atmospheric pressure that causes an increase in the pressure gradient between your body tissues and ambient pressure upon surfacing. In short, there’s a greater chance of forming a bubble unless strict guidelines are adheres to.

The PADI Altitude Specialty Course deals with the use of specialized tables and other practices that keep high elevation diving as safe as possible. Other considerations covered are thermal protection and the aquatic environment itself.

PADI Drysuit Specialty Course

Diving at altitude almost always means dealing with colder water than you’ll experience during your tropical vacation. In our case, water temperatures as low as 39 degrees (f) are common all winter, and even during the Summer when the water reaches a balmy 55 degrees, enhanced thermal protection provided by a drysuit is generally the diver’s best choice.

The Drysuit Specialty Course deals with all of the issues involved in diving safely in a drysuit. Like the Altitude Specialty Course, the drysuit specialty also includes making two open water dives. Both courses can take place entirely at the dive site, which generally makes for a fun time.

EANx, or Enriched Air Nitrox Specialty Course

Finally, EANx, or Nitrox as its commonly called is a breathing gas consisting of elevated oxygen levels in combination with reduced amounts of nitrogen. Since your body metabolizes (uses up) the oxygen, the reduced partial pressure of the remaining nitrogen means less of it is available to absorb into your tissues. (That’s not a 100% accurate description of the physics of what’s taking place, but there’s not enough space here to go into detail.)

Basically what this means is that, for a given depth, no-decompression bottom times are dramatically increased. For altitude divers this is very handy because we deal in theoretical depths, which greatly reduces our NDL.

However, diving with enriched air means accepting very strict rules regarding depth and oxygen tolerance, among others. It’s a big deal, but for the disciplined diver, Nitrox can be a godsend. For sea level divers, EANx increases bottom times dramatically as well, making gas consumption the limiting factor on most dives rather than no decompression limits.

So, there it is; the perfect trio of specialty diving courses for the cold water diver at altitude. Not surprisingly, these are also the most popular diving specialties that I teach. If you’re interested in learning more, you can reach me be email (joe@joescuba.com) or through Sierra Diving Center, (775) 825-2147. Be safe! Have fun!

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Deep See Pulse Dive Fin Review

  By Joe Ross • April 25, 2012 ,
Deep See Pulse Dive Fins

Deep See Pulse Dive Fins

Dive fins have undergone a revolution in recent years. In addition to countless designs using every material imaginable, split fins, fins with hinges, unique venting options, spring straps and every shape imaginable dot scuba diving self propulsion landscape. Despite the incredible range of options, a few of us divers simply want a fin that will push water and feel comfortable throughout the dive.

The Deep See Pulse by Aqualung is just the ticket for divers that prefer a paddle fins. Personally, I decided on the Deep See Pulse because it is similar in size to my beloved Apollo Prestige but lighter for traveling, and very inexpensive.

So, new fins in hand, er foot, I rushed out to make some dives. The first thing I noticed is the foot pockets seem to handle my large DUI Rock Boots better than the Prestige. I was concerned about this because the appear to be narrowing. Apparently, that’s an illusion because they slipped on with little effort. The shape of the Pulse’s foot pocket keeps the fins snug but not tight. So far, so good.

Once I started kicking, I immediately noticed the difference in stiffness compared to the Apollos. The Deep See Pulse is quite a bit stiffer. I can see how some divers would find that uncomfortable. On the other hand, stiff blades respond to very subtle movements, so I’ve always liked that-especially when taking pictures or shooting underwater video.

So, the bottom line is the Deep See Pulse is a well made, moderately stiff fin that’s light weight and feels good in the water. Split fin lovers will probably not like it much, while traditionalists like me will like it a lot. I’ve made about 40 dives with the Pulse so far and feel that I made a good choice. It’s also a great, no frills, fin for tech.