Cressi Leonardo Dive Computer Watch the first computer completely manufactured in house by Cressi.
The Leonardo is a complete RGBM computer with all the functions a recreational scuba diver might need, all wrapped up in this sharp Italian designed package. The large single button makes this diving computer easy to use with both Air or Nitrox whilst the large clear digits and backlight give an easy to read display.
Complete RGBM Dive Computer
Air and Nitrox Modes
Single Easy Button
Large Digits for easy reading
Backlight on Demand
User Replaceable Battery
-Air, Nitrox and Gauge modes
-FO2 adjustable between 21% and 50%
-PO2 adjustable between 1.2 bar and 1.6 bar -CNS oxygen toxicity graphic indicator -Single button interface (short push changes function, longer push selects functions) -Three levels of user-adjustable conservatism
-User-selectable Deep Stop function
-Modified Haldne and Wienke algorithm -Tissues: 9 with saturation hemi-phases between 2.5 and 480 minutes
-Ascent rate alarm (10 m per minute) -Log book for 60 dives/75 hours of information with 20-second sampling rate -Battery life indicator
-Distinct, easy-to-hear audible alarms
-User changeable battery -Adjustable unit of measure: English or Metric
-Built-in calendar and clock. -The instrument may be fully reset, in case of renting. -PC/Mac interface with dive profile (optional)
This computer is designed for use by those who enjoy being under water for reasons other than using the kit.
THE MANUFACTURE OF DIVE COMPUTERS originally fell to a couple of companies. In Europe, units bearing different brands all came from the same factory in Switzerland. Then that Finnish upstart Suunto got in on the act, though it kept everything under its own label. In the USA, a Bob Hollis company dominated the market, manufacturing for many different brands. Many companies that wanted something different went to Seiko in Japan. It made no computer under its own label but was happy to manufacture for others. The diving business is very small. I was once told that the entire annual production of current brand-leader Suunto in units equalled only 10 minutes of Nokia phone production. Similarly, Seiko makes a lot of products, and no longer seems interested in dive computers. This left those companies that relied on Seiko supplies in the cold. One, Cressi, decided to source its own unique product within Italy. It’s called the Cressi Leonardo.
The Algorithm Where do dive-computer manufacturers mostly go today for algorithms? One man has taken the limelight, and when he’s not busy at Los Alamos, Bruce Wienke likes to write decompression software for the leisure-diving industry. So far, to my knowledge he has done this for Suunto, Mares and Atomic, and now he has written a nine-tissue version of his RGBM algorithm for Cressi. Before any geeks write in to say that this is not a proper Reduced Gradient Bubble Model, I would like to mention that when the great physicist was questioned about this, he answered that it would be possible to write a pure RGBM only if it was also possible to miss out the shallow part of the dive. The algorithm takes into account silent micro bubbles that might form the nuclei of symptomatic bubbles during a second dive or series of dives.
The Instrument The Leonardo’s LCD face measures 4.5cm across. It’s hidden behind a protective layer of transparent plastic. The manly strap is long enough to go round any wrist clad in a drysuit cuff, while being easy to replace if necessary. The computer is set up using a single button, which is pressed in sequence to access the various menus. When adjusting any part such as the nitrox setting, one must be careful not to overshoot, as it is slightly irritating to have to work all the way round again. When I first set it up, there was some frantic button-pressing, accompanied by one or two harsh words.
In the Water At a time when diving Internet forums are full of recommendations to buy technical-diving computers on the grounds that “you’re going to need one, one day”, it was refreshing to get into the water undaunted by any lack of IT skills. This computer is designed for use by those who enjoy being under water for reasons other than using the kit. It proved straightforward to use, gave clear information, guided me as to when I was better off pausing for a minute or two at depth on the way up, gave a clear indication of remaining no-stop time or deco requirements, and beeped at me if I went up too quickly. It indicated clearly the safety-stop time and, if I needed to see the screen more clearly in the dark, a button switched on the backlight. Not only that but, unsurprisingly, the information it gave regarding decompression requirements during the dive was not dissimilar to that given to me by the Suunto (also using a Wienke RGBM) alongside it, including the option to enable deep stops and a variable safety setting. What more do you want? You cannot program in your own gradient factors, or your own algorithm for that matter. Wienke, in his infinite wisdom, has done that for you. Buy it, set it, strap it on and go diving.
After the Dive Finally, what a pleasure it was for someone who works in media to find that the computer interface and software for the Leonardo was equally at home on either a PC or a Mac. Times are tough, and Cressi has brought this Wienke-type computer to the market at a fiercely competitive price. I imagine that we’ll be seeing a lot of them at dive sites before long.
Cressi Dive Computer Leonardo Features:
“User-Friendly Display System”. The information display, screen contrast, proportions and digit size have been carefully chosen for ease of use. All of the information presented is separated by light lines to facilitate reading even in stressful or emergency situations. Back-lit display activated by button or when alarm sounds
It is a rugged and completely modular computer with a wide UFDS display, providing ease of navigation and Cressi software menus
Low relief profile with ergonomic design to properly fit the wrist and allow free movement of the hand
Single multifunction button for lower production cost, greater reliability and ease of navigation
DIVE MODE (“DIVE”) :
Versatile Air/Nitrox ranging 21%-50% O2 with 1% increments
Modified 9-tissue Haldane Algorithm
RGBM + Deep Stop (optional)
Algorithm customizable on 3 levels (Safety factor: SF0, SF1, SF2)
Allows successive dives with different mixes (indispensable for reprogramming a mix when using Nitrox)
Adjustable PO2 of 1.0-1.6
Dive Planning Mode
Independent logbook by mode: 75 dives or 60 diving hours with 16 pieces of information about each dive
Profile Mode: Minute by minute on-screen profile of all dives logged in the logbook
Variable ascent rate with visual indicator and visual and acoustic alarms
Acoustic and visual alarms with screen lighting: PO2, CNS, ascent rate, DECO, DECO bypass
Calibrated in salt water for maximum precision
NO DEC TIME and DEC TIME with three digits
Optional decompression safety stop (“Stop”) in case of no-stop dives
Approximate 3-year battery life (50 dives per year)
Temperature, instant PO2, time and mix used are visible under water at the push of a button
Back-lit screen (one press, 5 seconds)
Reset option accessible through the menu. Eliminates the residual nitrogen memory for rental or instructional use in dive centers
GAUGE MODE (“GAUGE”) :
Designed to provide precise basic diving parameters with mixes with decompression tables through a specific program
Gauge calibrated in salt water (maximum precision)
Current depth reading, maximum depth, dive time and temperature