dickb wrote:One big difference between magic arm/hydrostatic arm solution versus the locline type is that you can easily adjust the locline arm onehanded. The cheap magic arm I have needs two hands to adjust, as it doesn't hold any weight once you release the central knob. Better designed hydrostatic arms probably exist, maybe someone can recommend a specific model.
Good point about one-handed vs two-handed but don't confuse hydrostatic with a regular chinese magic arm that sells for a few dollars, also called articulating arms.
The hydrostatic type are pressurized with fluid, like a fluid type video head, so even even with turn the lock knob all the way 'loose' or unlocked, the arm stays in place with a flash due to the low weight. If you push down on the unlocked arm, it droops slowly, like a fluid video head pan or tilt movement.
That could be good or bad depending on what you are looking for.
My Bogen/Manfrotto hydrostatic/fluid arm locks 100% in about 1/4 turn, its quick. The chinese articulating arms that I own, at least a dozen of those, take about 2 knob rotations to lock tightly.
locline arms are easy to move with one hand, but they also like to move on their own
Also I never could get them to hold the flash, subject, reflector, diffuser or whatever in the perfect position without lots of fiddling since they like to flex and droop with weight. So you have to set the position higher than you want since the locline arm will droop and flex a little. locline works best left in the a machine shop where it came from.
Nothing is perfect and all solutions have pros and cons.