camera stability - is magnesium body necessary?

I'm sure this is a re-post, but yes, I have searched so I thought I'd try to get some thoughts on this...

I currently have an XSI with support setup of a vintage aluminum Gitzo tripod and a 2003ish Gitzo magnesium ballhead. The support set up itself seems amazingly solid and a appears to have little to no issues whatsoever. I do wonder however about the whether the plastic rebel body is holding it back or not. When checking out the setup before a shot, it appears that any flex I do have is at the body, not the support system. The thing it has going for it is that the rebel is super light, but this all becomes irrelevant if the body is flexing at the base attachment

I don't have any particular shots to show where I've had a problem, it works well in practice. I do wonder, however, how it would hold up if I was try some really long exposure night photos whether this is going to be a problem. Without upgrading lenses, I can't really tell if the ever-so-slight drop in sharpness is from the lens, my focusing or from the tripod stability.

Thanks for wasting your time reading my ramblings, I'd love to hear some quick thoughts from someone who has used both the rebels and the higher-end bodys.

How are you checking for the flex that you've identified? What focal length lens are you using? From what I've seen, with my 40D, there is a slight bit of vibration when letting go of the tripod anyway.

Are you using mirror lockup and a remote trigger or 10 sec timer before taking your shots?

Remote trigger, yes, but not mirror lockup. I either use the remote or the 2-sec delay on all tripod shots but I'll have to try to be better about hooking up the remote or else give 10-sec delay a try.

I'm not regularly using mirror lockup so it looks like I have something easy to try before blaming the camera.

When I say I'm checking the flex, I pretty much just mean tapping around on the camera and tripod after I set it up, to try to make sure its got a good grip on the ground and everything is firm and its not on a rock or loose dirt or anything. As far as the shots, I'm usually using the 55-250 ef-s or the kit 18-55 lens. I'm just getting started here, so I hope to upgrade the lenses relatively soon, but I was hoping to verify what my weak point is before I spend more money.

I think the extra weight of magnesium does add stability. It won't be enough to affect IQ though.

I find that a magnesium body feels more solid, and the extra weight makes the camera feel more proper.

I've used a Rebel and have a 40D, and my primary use of both has been in situations requiring a tripod, since I prefer to not use flash. I learned about mirror lockup(MLU) before I started to seriously use the former Rebel, and I've pretty much stayed with that in low-light/long-exposure situations.

At the same time, I've used both on a tripod and the 40D on a monopod, and have not seen any evidence that the Rebel has been compromised in any way by having the plastic body. The tripod mount socket is firmly attached to the mirror box, which also has the sensor fastened to it, which comprises the mail physical assembly of the guts of the camera.

The situation may become a real issue if using long & rather heavy lenses, in which case a ring or other device attached to the lens barrel is also the attachment point to the tripod, creating a more even weight balance.

i think you're worrying too much. i'm not sure how the body of the camera can flex after you tap it. either you have some crazy strength, or you're seeing something else. just make sure that the body is mounted securely to the tripod head. if your tripod has a hook on the center column, you can use that to hang a weight or your bag on to weigh it down more. that should give you a bit more stability.

anyway, stop looking for faults and enjoy the camera you have. once you feel the equipment is limiting you, then think about an upgrade. but don't just go looking for them, unless you're looking for a reason to spend money.

keitaro wrote in post #10813908
I think the extra weight of magnesium does add stability. It won't be enough to affect IQ though.

I find that a magnesium body feels more solid, and the extra weight makes the camera feel more proper.

2 lbs of plastic is just as heavy as 2 lbs of metal. Just so no one makes the stupid conclusion that the 60D isn't good enough for tripod work...

The chassis is steel, so whether the plastic flexes or not (it doesn't) is irrelevant.

Agreed. If you are seeing slight softening from any motion in your shots I see two possible culprits in your description:

1. not using MLU. That mirror slap makes a fairly noticeable difference, especially in shorter <20s exposures. NOTE: If you are using Live View, you are automatically, effectively, in MLU as the mirror is up out of the way for LV.

2. Make sure IS is off on both of those lenses when shooting from the tripod. Most IS systems will try to activate while on the tripod and can cause motion blur themselves. Learned this one in some puzzling night shots a couple years back

And if you're tapping around you're going to transmit SOME vibration through the rig. I doubt that anything you're seeing is a result of the frame composition of your camera.

Go out, shoot, have fun

didnt see this mentioned yet... but if your tripod has a center column, make sure that you are NOT extending it (at all). for the greatest camera stability, the center column should be all the way down, resting on the top of the legs.

~mike

Also, you are much more likely to have trouble on shorter time exposures. 1/10 to 1 sec are much less forgiving than really long exposures because the vibration resulting from the shutter movement is a much greater percentage of the shot. So...if you have a choice and your subject isn't moving lower the ISO and lengthen your shutter speed a bit.