I am using some Odyssey LTP1/2 light stands with a T-bar and then loaded up with 4 "Blizzard Fab5". I've been looking at adding some sand bags to stands to keep them planted for a little while.
But I am not sure on:
Which bag weight should I get?
How many per stand?
Where the best place to buy these? (I'm looking for pre-filled).
Unless you've got a ton of weight at max height, or have to collapse the legs a bit to a smaller extension, a pair of 20-25# bags per stand will be fine.
Don't waste your time with pre-filled, unless you have no access to a Lowe's or Home Depot. The shipping isn't worth it, and sand at your local home improvement store is around $3 for a 50# a bag.
It helps to have dry sand in the bags, but drying sand in this weather is tough, unless you have a garage where you can spread a tarp and dump the sand to dry. The easiest thing to do is fill gallon ziploc bags with the sand, and tape them shut. I have these 2 versions:Sapsis 25 lb bagePhoto 20 lb bag
With the Sapsis bag you can fill the ziploc first, with the ePhoto bag you need to line the sandbag with the ziploc before filling in order to get a full 10# per side in there. The Sapsis bag is a little nicer construction, easier to fill, and having the extra 5# in there is nice. The handle is a little different than what is shown in the picture - more like the ePhoto bags (spans across the middle) and is made out of material like a seat belt, so it's flexible but durable.
The ePhoto bags are inexpensive but good quality, but the zipper closure concerns me that it may eventually fail. Fortunately it will only ever get reopened if the internal ziploc bag fails.