31 May 2015

Superzooming

Now that photographic technology (at least its non-glass parts) has evolved into the digital age, it advances much more quickly than it did in the analog era.  Sometimes, it becomes easy to find what would have been unimaginable a few years earlier.  I tend to be something of a cheapskating late adopter, and find that previous models often provide powerful capabilities to use and grow into, at impressively low cost. In this vein, I recently jumped on the chance to purchase a Canon SX50HS (introduced in 2012), my first venture into the superzoom category. Its then-astounding 50:1 zoom range tops out at 215mm, offering equivalent magnification to what would be a 1200mm lens on a 35mm camera. I was able to pay less than $200 USD for the entire camera rather than the $180K currently quoted for a rare and massive 1200mm lens. Naturally, the image quality isn't the same, but I think it's quite usable by my standards.  Also, it's small and light enough to be reasonably wearable (and, hence, conveniently available) rather than haulable.  I took it out for its first bird walk yesterday and was pleased to be able to collect this shot of a tree swallow peering out from its nest hole.

Capable viewing, looking out from a small enclosure. I can appreciate that. 

16 May 2015

Longest. Progress Bar. Ever?

I've been using a MacBook Pro for a few years, which I’ve been quite happy with except for some annoying behavior when resuming from hibernation. Being Security Guy by habit, I’ve unsurprisingly been using FileVault disc encryption; after typing a password to unlock the volume, I’d often been waiting for a minute or so, sometimes spanning a screen blank and reset button tap, before being presented with another password entry prompt and the chance to enter a useful system. (Deceptive UI indication aside: please don’t provide a blinking cursor in a text box before it’s ready to accept input!) Accumulated impatience having eventually spurred me into action, a web crawl yielded references like this article, suggesting that OS X Yosemite was intolerant of at least some earlier FileVault configurations and recommending decryption and reencryption. I started the decryption on a disk with about 140 Gb in use; though it changed before I got to screenshot the display, the progress bar started out with a caption estimating 43 days to complete the task. That proved conservatively pessimistic, with the operation taking about 10 hours in the actual event. I’m used to symmetric crypto being quick, often invisible inline at human scale; 43 days read more like what I’d expect if a fairly substantial exhaustive search had been required.