Shaking viewfinder image in Canon 550D

Question

Sometimes I put my viewfinder to my eye before I turn on my camera. When I turn it on, the viewfinder image slightly shakes and moves a bit vertically. This also happens when I look through my viewfinder and press the shutter when the camera has been on, but not used for several minutes.

My camera is a 8 month old Canon 550D and I use it with a Sigma 18-50 mm f/2.8-4.5 DC OS HSM lens.

As it happens sometimes, the behaviour is hard to reproduce and hence I can not give you more information about the problem.

Does anybody know why this is happening?

Asked by Bart Arondson

Answer

As forsvarir says, it's most likely the optical stabilisation initialising.

And to clear up one of you comments; In a DSLR you will only see a stabilised image in the view finder with a stabilised lens. When you look through the view finder you're not seeing a picture that have been captured by the sensor first. So any stabilising happening on the sensor is not visible through the view finder.

With a mirror-less camera where you use the screen instead of a view finder sensor stabilisation will be visible.

Answered by Håkon K. Olafsen

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