[Guest]

I am using Canon 600D, I have Tamron 70-300mm VC USD (A005) and noticed if I turned on the VC, look through the view finder and press half the shutter to focus I can see the picture in the viewfinder will be a tiny "shake". Someone says that is Tamron's VC normal.

 

Now I just bought 90mm VC USD (F004), and did not have this "Shake".

Not sure which one is right or 90 mm VC is better?

 

How do I check if the VC is working or broken?

 

One way to visualize handshake is to use liveview and set the magnification to 10x. Even with shorter focal lengths, where handshake is not so apparent (unlike teles), you should see how you shake. Turn on the VC, and it should be a lot smoother, it may not freeze completely, but change to a smooth, damped movement.