Camera mirror shake

[Overread]

Just how bad is it? Well take a look
SLR shutter tests

Shows not only the wabble that the mirror goes through in its rapid motions, but also the amount of wear these components take

 

[Soocom1]

Hence Mirror Lock up.... lol....

 

[KmH]

Checkout all the movement in that second curtain too.

The durability sure isn't all that great.

So a mechanical mirror system like that is good for 100,000 cycles. Lets say, 200,000 cycles.

My computers CPU does that many cycles in a fraction of a second (no moving parts, if you don't count the electrons).

My racing kart's 2-cycle engine at peak revs is hitting TDC 15,000 times a minute, or 250 times per second. It has to be rebuilt after every 10 hours of racing time though, or it goes KA-BLAMMO somewhere during hour 11 when the rod or a crank bearing fails.

Imagine the increase in complexity if they tried to control all the bounce and slap.

 

[Sw1tchFX]

I'd really like to see that same video with a 1D, a D3, and a D700. I bet either of those cameras doesn't wobble shimmy and shake NEARLY as much as a 5D. Much stronger since they're built for 8-11 fps. The 5D's shutter doesn't feel all that solid anyway when you're shooting.

 

[KmH]

I think I recall there is a video of a D3.

Here it is, but it's not a video.

 

[Derrel]

Wow, very cool link. Funny thing--it looked to me like the camera that had the last mirror slap and the least mirror bounce after the shot was the lowly Rebel XT!!!!!

Not trying to start any N vs C war, but I think Nikon developed some new types of mirror bounce dampening system to cut down on both mirror slap and mirror bounce problems once their d-slr's got to the 5 and 8.2 FPS point with the D2 generation bodies, and I know that Sony's A900 has an entirely DIFFERENT mirror motion--not the ages-old hinge point at the back of the mirror, but a system that sort of "lifts skyward" the mirror while tilting it upward. In other words, Sony has developed a new two-axis mirror lifting system, which you can see illustrated here.

Sony launches flagship, full-frame Sony Alpha DSLR-A900

I would love to have seen a professional level 1D-series Canon body in those high speed tests, because I think their newer pro-grade bodies also have anti-bounce systems integrated into them. What we saw were basically lower-level engineering cameras relying mostly on the lowest cost engineering possible at a "given" price point. I went back again and counted the number of mirror slaps and the return mirror's vibration dampening,and it does look like the Rebel XT had the least slap and the least bounce,but then it also probably has the absolute slowest mirror up and mirror down times of any Canon d-slr. It looked to me like the 5D and 20D were the worst on both mirror slap and mirror bounce...the 20D's mirror bounced like a rubber ball when it came back down! The 50D looked pretty good on both counts.

Addendum: Okay, so my memory WAS right. Nikon built a new "mirror balancer" when they introduced the D2h sports camera that the mirror in the D2 series bodies "completes its motion and reaches a full stop without any mirror bounce. This stable mirror movement allows for faster AF detection which provides for more accurate focus tracking and only blacks out the viewfinder image for only 80ms". There's an illustration of this mirror balancer system here Nikon D2h-Slr Review: Image Sensor, Af, White Balance

Of course, it's not fair to compare the D2-series pro-level bodies which were priced at $4995 and $3495 several years ago to $1400 and $500 Canon consumer bodies. A quick search shows that in 2005 Canon's 1Ds Mark II had their "Active Mirror Control" system which allowed Canon to nearly equal Nikon's 80 millisecond blackout time with an 87 millisecond blackout time; these times are significantly faster than what consumer-level bodies turn in.

I know that Nikon's F5 from 1996 and Canon's EOS-1 both had systems designed to keep mirror bounce and slap to a minimum,and those systems have been refined during the digital era, but mostly only at the top-camera level where the firing speed, and the retail price, makes it a desirable feature.

The one I would like to see is the old Pentax 6x7's mirror....I bet at 2,000 frames per second it would look like a small earthquake when that massive mirror slapped upward!