Battery grip.. why?

Scooby888 wrote in post #14834675
If you buy the OEM grip this won't happen. My grips are tight, tough and never let me down. No flex

The Canon grips cannot avoid the laws of physics. If you add more form factor to the tripod connection point (grip), then you will add flex. It also makes a longer pendulum out of the system. If you throw a 24-70 on a Rebel and time the tripod settle duration, it will be higher with any grip than without.

As I mentioned earlier, I have both a Canon OEM, and a Targus brand grips for my XT. There is one difference that I can see, and that is the decals. The Targus was just as secure on the body as the Canon, and it had no flex. I don't have monster lenses, but both are fine on a tripod. The Targus also has a place for the battery door. I bought the Canon thinking I was going to get a much better built product, and realistically, I just got a duplicate with the Canon name on it. I'm happy with both, and would recommend either.

Scooby888 wrote in post #14834675
If you buy the OEM grip this won't happen. My grips are tight, tough and never let me down. No flex, work perfectly on tipods and hold the battery cover should you with to remove them in the field.

I suggest you get what you pay for, although I believe Meike make a decent grip if you are trying to penny pinch.

My 7D grip is OEM. It flexes. Mounted on a tripod, just look at the bottom will pushing the lens from the top.

snake0ape wrote in post #14838617
My 7D grip is OEM. It flexes. Mounted on a tripod, just look at the bottom will pushing the lens from the top.

All grips flexes. It's quite visible if aiming the camera at something in live view, and then look at the sag as the grip + head takes the load. Some of the sag will come from tripod + head, but some sag will come from the battery grip.

Besides the flex in the grip it self, there is the issue with the two screws holding grip to body and grip to tripod head. The grips aren't really designed to tighten these screws as hard as would be needed to fully take up the twisting forces from a heavier lens. The screws need to be preloaded with a very high force, and both OEM and third-party grips can be destroyed if trying to tighten the screw too much.

Luckily, the extra sag from the battery grip normally doesn't matter too much. With bigger lenses, you would use the tripod collar on the lens anyway which both remove the battery grip from the equation and at the same time removes most of the torque - as long as the camera is aimed forward, and not at a significant angle upwards/downwards.

+1.