I bought a Canon XM2 (PAL - GL2 NTSC) several months ago, and have been generally pleased with the performance of the camera.

However today I have discovered something not very good at all, as you can see from the WMV clip in this link [1.5mb .WMV file]:-

telephotowobble-1.wmv

Looking through the viewfinder, when I am zoomed in on something, the picture wobbles badly. Just to confirm I am using a steady tripod, with all automatic settings turned off. For those who cannot see my example from the above link, it is best described as a 'ripple' effect, as if the image is being seen underwater from above the water. Or like the 'heat rising' effect you see in 'desert road' film scenes.

This happens increasingly as the camera approaches the long end of the lens, and reaches abysmal levels going further when I experimented with the 100x digital zoom [I am aware digital zooms are 'bad' quality anyway, but the unwanted effect is also clearly present in normal zoom].

I at first assumed the camera was fighting with itself over auto-focus or something similar, but after experimenting with all settings alternated between manual and auto this appears not to be the case. 'Image Stabiliser' on or off makes no difference.

After experimenting for several hours today, this is what I have found:-

> When I shot through my OPEN back window at a sun-lit patch of grass, this terrible 'ripple' effect as I zoom in

> then through my CLOSED back window at same sun-lit patch of grass, same effect

> then through my OPEN front window at a sun-lit brick wall, same effect [see above link]

> then through my CLOSED front window at a sun-lit brick wall, NO 'ripple' effect

As I am typing this and the sun is going down, I have just tried shooting the grass through the back window again, with window both open and closed. The 'ripple' effect is still there when I zoom in, but it is definitely less than before.
Also, my front window is [ahem] rather dirtier than at the back.

So based on this, could it be a 'light' issue? I have experimented with exposure settings [shutter/iris/gain/ND filter] and can still see the unwanted 'rippling' even when the picture is dark. Thinking the problem may have been just in my viewfinder, I digitised the footage through my normal firewire route into Avid Liquid to find this was not the case.

Most importantly, has this been heard of before, and is my camcorder faulty?
For the record my XM2 has been treated with kid gloves since I bought it, and never subjected to any mishandling, extreme tempteratures or bad storage.

I don't know if the camera has always behaved like this, because to be honest today was the first time I had a chance viewing of a tripod-stabilised telephoto zoom. All I have done differently recently is attached a screw-on UV filter today. And yes I get the same 'ripple' effect near the long end both with and without the filter attached.

Any insight on this greatly appreciated.