. ... However, the advantage to software is the ability to a) record your dives AND print a hardcopy for your log book b) have an electronic backup copy (I lost my original log book about 15 years ago and REALLY wish I had it now) ...
I've mentioned it in prior threads, but I
back up my paper logbook by scanning it to a pdf file. Multifunction inkjet printers that print/copy/scan/fax are pretty common these days. A 300 dpi b/w scan is quite readable, and 2 pages (2 dives) scanned to a page is roughly a 1 MByte file. Two thousand dives will fit in 1 GByte, which makes it reasonable to carry almost anyone's entire dive history logs on their laptop hard disk, or on a USB thumb drive, or on their iPod, etc. Scanning a dozen dives after a trip takes about a minute a page or so. Neither terribly time consuming, or much data compared to e.g. photos or mp3s.
I also upload my Cobra to
DiveLog on my Mac, and then back that up both as the native xml data file, and formatted/printed with profile graphs etc. to a pdf file on disk. With that saved off on both my external hard drive backup, and an archive DVD, I got to thinking about my paper logbook with all the anecdotal stuff, and how I'd hate to lose it. I thought about photocopying it, but then realized how much more flexible and compact it is to scan it to disk.
I have both forms of log (pdf image of Divelog printed output, and pdf file scan of my paper log) on my laptop, and also on my iPod touch (using Air Sharing, see
Avatron Software Products ). Always with me on any dive trip.
One other related thought: I also keep scans of my passport, drivers license, C-cards, and DAN card on my laptop and iPod. Higher-res jpg color scans for those. Another form of backup.