Sunday, October 30, 2011

Tie Downs

I've heard enough stories about cameras being blown over in heavy winds on lightweight tripods. I envy the guys who can shrug off the loss of their SLR and often run with backups for everything, but I, unfortunately, am not one of those. I'm the sort who puts my poor camera through tens of thousands of shutter cycles over many years, trudging through swamps, car races, helicopter flights, and other adventures without getting more than a few scuffs to it before the charging system finally dies or some such. Actually: My last DSLR still works well but eats batteries. I bought it in 2001, and used it for most of my nature photography until the Nikon D90 in 2010. The grip is worn down and it smells like a wildlife refuge.

So between that record and the realization that with such a lightweight system even a mild breeze could cause camera shake as is the system needs mass to keep it steady. Except of course I don't want to carry much extra mass.

Couple of ways I could think to solve this would be to fill a bag with rocks, sand, etc when we got there, or to hang one of our packs off the bottom of the tripod. At most we're talking 25ish lbs of force though, and at night a pack would have to be unloaded of food so as not to attract animals.

Solution? There's a whole lot of mass straight down to anchor in to. So this afternoon I spend part of the day with a torch and welder making a ground stake system that screws in to the firm earth:


At first I thought I would use a couple of pulleys and paracord to pull the tripod tight to the anchor, but it proved messy. I couldn't get a consistent pull on the cord, and even when everything went well the force was lower than I had hoped. Solution? Ratchet strap. This allowed me to put a couple hundred pounds of hold down force, even in the soft grass/turf in my front yard. The results were a platform that is rock solid; I think it would still be standing after a tornado.


I will already need the ratchet strap system for my cable dolly, so nothing added there. The anchor itself clocks in at 115 grams, or about a 1/4lb. It's really overkill, so I may remake it, but in the mean time it's making me comfortable about my camera's safety should there be much wind involved. Plus it will assure a steady sky tracking.

3 comments:

  1. I've got those same ratcheting tie-down straps, oddly enough. Well, I have one of them at any rate. The other tore through as I was using it to support my heavy bag, and it didn't take well to being slung over a rafter beam and knocked back and forth. With no beam to saw through it it should be quite sturdy though; the mechanism had no trouble holding a 100 lb bag 24-7 for 8 months before the nylon got cut through.

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  2. Might test this in harder soil? And what about boulders and such? Can't really know where you will be.

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  3. Do you think it would be wise to put some padding or hockey tape on the anchor or tripod hook? I doubt I'll put the kind of abuse the ratchet strap that you did, but I'd hate to have that be the thing that fails in the field.

    Clay: I tried it in some places with rocks in the soil, which is the best I can do here. If I'm on boulders I'll have to improvise. Perhaps a couple of loops of para-cord around a boulder and then strap to that... I'm not sure. I think it will be one of those problems I just have to get fancy in the field with, as you eluded.

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