Well, I took the Luma Labs Loop 3 out for its first real use test over the weekend, and it performed well. I have the Cinch (fist generation), so I'll be mostly comparing it to that. I don't work for Luma Labs, but I do like their products and follow them closely so when the preorder announcement came out on their e-mail newsletter I jumped on it. Some people in the Cinch thread have been asking for a review but I feel that it would be best to just start a new thread about this strap as it differs from the Cinch.
First, a few pics..
A few shots with the S100, bad light and I am no product photographer..
Loop 3 on my 70D:
Luma Loop 3
by slcko, on Flickr
Luma Loop 3
by slcko, on Flickr
Luma Loop 3
by slcko, on Flickr
Luma Loop 3
by slcko, on FlickrNow, on to the strap itself.
Like all Luma Labs straps, this one is of the best quality. Heavy rivets hold the D loops into the shoulder pad, which is a die cut piece of leather with the Logo sewed to a die cut piece of neoprene. The shoulder pad, while it does not look thick, holds my 70D with the 70-300L on it comfortably and as effortlessly as the Cinch does.
On the strap there are 3 of the Cinch 2nd generation sliders. These are some kind of custom carbon fiber filled polymer stuff and are substantial. They feel rock solid and are lighter than metal and won't scratch your L lens barrels should they get up against one in a bag. The front slider is for "cinching" in the strap in a similar fashion to the Cinch straps. This lets you bring the camera up and snug against your body, which prevents it from flopping around like it will tend to do with other sling style straps. I did find that getting it to "cinch" up was a little more tricky than the Cinch 1. Without a pull tab and because the camera can move freely, you have to lift the camera up with your right hand while pulling the slider down with your left to get the leverage you need to get it to tighten up. Releasing it is just as easy as the Cinch straps as the camera weight is working for you and it can be done quickly with one hand. The back slider closest to the shoulder pad is designed to adjust the overall length of the loop. Closer to the pad, the longer the max length, closer to the camera, the shorter the max length is. The final slider is "free" in that the doesn't affect the strap length at all, it is there to provide a stop to keep the camera from sliding freely along your back. Properly positioned you can lock the camera against the front slider and the back stop and really secure it.
On to the coolest part of the strap in my opinion, the fully custom camera mount hardware. The tripod nut is a chunky captive hunk of aluminum that looks like the hilt of a lightsaber or something. It goes into a black anodized offset D loop that has a rubber backing to go against the camera. The nut lets you get a lot of torque on it to make it a very secure fit, yet it is shaped such that it won't catch on other things to accidentally come loose. With the rubber providing some counter pressure and dampening I don't see this working loose unless you intentionally loosen it, but as with all single attachment point straps it is a risk and should be checked periodically. I like the fact that there is no hinge to be a point of failure in this design and there is no chance of the metal in the mount to get pressed up against the camera in a bag.
The offset nature of the mount combined with the fact that it sized perfectly so the strap cannot easily twist means that the camera is held very stable during use. I've used it with my 70-300L and the 17-55 with a 430 EX II on my 70D, and in all cases the camera did not move around much when down at my hip. It is held in a similar grip out position as the cinch straps and it won't rotate much at all. The Cinch straps tend to hold the camera in a grip out lens straight down position, this one is a little different in that the lens is at more of a 45" angle (depends on where the center of gravity between the lens and the camera and the mount is) I actually prefer this as I have less lens creep and the viewfinder isn't facing straight up into whatever is coming from the sky (direct sunlight, moisture, etc). Going to shoot I never had to reorient the camera to get to the grip, it was a natural movement to get the grip and pull the camera up to shoot. Going from hip to shooting is a great experience - I could not use backpacks with the Cinch as it prevented the strap from being able to slide around my body. Since the camera can move freely along the strap this is not a problem with the Loop 3.
Running through some stability tests, I was able to jog and lean over without the camera bouncing around much or trying to come forward. While the camera will always have more freedom of movement than a two point strap, it is still extremely stable for a slider. The ease of shooing far exceeds the cost of having the camera move a little more for me.
Overall, I am really happy with the Loop 3. It seems to combine the best parts of the Cinch and a sliding "sling" into a solution that still provides stability while offering the freedom of a sliding camera strap.
