I have been employing the Manfrotto 501(old style, non-HDV) fluid head with my 20X80 and 25X100mm binoculars considering the fact that 2001. The 501 head operates well with optics from ~3 lb to 10 lbs. I discovered about the new 701 HDV in late 2008. I was in search of a much more compact mount for field use. I liked the concept that the 701 HDV head use the same 501 PL rapid release plate because the 501/503 fluid heads. All of my giant binoculars and spotting scopes possess the 501 PL attached. Having the 701 HDV head means I can swap optics on distinct mounts swiftly. I ordered the 701 HDV from Amazon/Ace Photo Digital in early March 2009. Attachment (bottom): 3/8'' female thread; attachment (leading): 1/4'' and 3/8'' screw; balance manage: one fixed spring for 1.5Kg camera weight; bubble spirit level; color: black; counterbalanced; front tilt: - 60Degree / 90Degree range; height: 3.74 in.; independent pan lock; independent tilt lock; load capacity: eight.82 lbs.; material: aluminum; 2 pan bar positions; 1 pan bar integrated; pan drag: fluid cartridge with fixed drag; panoramic rotation: 360Degree degrees; plate form: 501PL; swift release; sliding travel of plate: 2.28 in.; tilt drag: fluid cartridge with fixed drag; weight: 1.83 lbs.; operating height: 3.74 in. Silky smooth pan and tilt action. Constructed in swift release method. Sliding fast release plate enables great camera balance. Extra pan bar (bought separate) could be attached for extra smoothness. It is rock solid and silky smooth. I've read some reviews stating that the small lever which you turn to lock-in the camera with is a style flaw; so I wanted to add a seriously very simple remedy. After you get the head, you'll push that lever and it will get tight when it pretty a lot touches the bottom from the camera. This tends to make it really tough to loosen, simply because you cannot get in there with your finger to push it down. I've even read that a number of people usually carry a flathead screwdriver to pry it open. That's just silly. Here's a 30 second repair. All you will need is an allen crucial. Created particularly to support the latest prosumer and specialist light compact HD camcorders, the 701HDV offers an updated design, which has been created for improved ergonomics with locks and knobs that permit for any much more solid grip and improved control, a much better fluidity due to improved internal fluid cartridges, a double pan- bar rosette plus a larger sliding plate to optimize the position of your camera thinking about its centre of gravity. The 701 HDV is really compact in comparison to my 501 head. I would estimate just over 1/2 the volume. Fluid motion is really smooth. A lot far better than the 728 digi tripod/head I purchased a number of years back. Fixed counter balance spring functions very well for my three.five lb bino. I was not planning to work with this head with my heavier optics however the 701 HDV operates fine with bigger binoculars up to my 8.5 lb 25X100. ( to my surprise). Take out the small screw that holds on this teardrop-shaped lever, pull it off, and rotate it 90 degrees counter-clockwise and put it back on. Now when it becomes tight, it will not be hitting the bottom on the camera. The 501 Plate permits about 3 inch of fore and aft balance. Works considerably much better than Bogen heads making use of the 3157 PL. This compact fluid head are going to be considerably simpler to carry inside the field in than the bigger 501 head (rated for 13.two lbs). I strategy to add a second pan manage to produce panning even easier.