Mast camera

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I've been keen to take on-the-water photos of flying sails, and finally saw an inexpensive, small, and light digital camera.  Round the same time I noticed that my experimental Cuben fibre sails seemed to have a rather different shape on the pond-side than on the water.  Time to investigate.  The camera is about 50 mm x 55 mm square, and about 15 mm deep.  Powered by a single AAA battery, it weights about 35 g, and cost about 40.

The top shot shows the camera on its first outing, so it is tied on in a rather untidy fashion at the top of the mast.  The 11.1 mm dia. mast is extended above the backstay crane with a length of 12.7 mm dia. tube, whose lower part is sectioned in half.  It clips over the mast quite nicely.  To the extension attaches a second tube which carries the camera.

In order to take a series of snaps while sailing, the shutter button must be kept pressed down.  So the lollipop stick serves as a finger when the yellow elastic is hooked to the base of the camera mount.  Two resolutions are available when taking "streaming snapshots" -- low 160 x 120 which gives about 160 seconds of snaps at about 3 fps, and medium 320 x 240 which gives about 80 seconds at around 2 fps.  This picture is typical of the medium resolution -- so it is, ah, obvious that you get pretty much what you pay for.  The water looks black (I've cut out much of it from the photo) because the camera has automatically adjusted its white exposure setting to accommodate the very white sails and deck patches filling the lens.  If I feel encouraged, I may splash out on a camera with better optics.

Downloading the pictures is very straightforward with the USB cable supplied and the camera software loaded onto a laptop.  Single snaps come in as JPGs, while the "streaming snaps" come in as AVIs.

The snaps could be improved by better placement of the camera so as to catch the aft end of the top mainsail draft stripe, and by inking the upper side of each boom a nice dark blue to provide contrast and the baseline measures for twist.  Also, the bottom draft stripes could probably do with being maximum width (30 mm), rather than the 20 mm which I've used.

My planned future enhancement is to be able to take single snaps.  Resolution for single snaps with the camera is 640 x 480, and it claims to be able to store up to 100 in its 8 MB memory.  I plan to mount a micro-servo in place of the lollipop stick, and use the third channel of my Tx to press the shutter button when needed.  Instead of "watching this space...", here it is.

2005-12-18


2011 Lester Gilbert