Spots on CMOS sensor (EX3)

[Steve Phillipps]

This is a bit strange. As Alister pointed out, sensor dust should show up as dark spots.
As for cleaning the sensor glass AFAIK you should just treat it like you would any other optic (lens, filter etc.), so normal lens cloth/tissue/fluid should be OK. In fact the sensor cleaning stick etc. for DSLRs should be best bet.
Good luck getting to the bottom of this one!
Steve

[Alister Chapman]

Still looks like dirt on the front of the lens to me. What aperture are you at? The EX camera are best used between F8 and F4. Stop any lens down far enough in bright light and you will see dust.

It isn't unusual to have a few specs of dust on the ND filters or IR filter, these don't normally show up at all.

[Dave Morrison]

Looks exactly like a dirty front element to me, too. The only time that dust will light up like that is when you have sunlight directly falling on the dust itself. If it's anywhere else inside the lens or inside the camera, they will show as dark spots. Before they replaced my first lens, I didn't even notice the crud inside until I stopped down and pointed the camera toward the sky.

[Christopher Dye]

Okay. Upon closely examining the front element of the lens with a penlight, there was dust on it, but it's very hard to see unless you angle the light just right. Otherwise the lens looks crystal clear. I did put a protective filter on the lens not long after receiving the camera, so this is why I figured it couldn't be dust on the front of the actual lens, but it does appear to be the culprit.

I cleaned the front element of the lens with Tiffen Lens Tissue as well as a Lenspen, but it just seems to be moving the dust around, not lifting it off, as the dust is still there, but not as prominent. Maybe I'm too much a perfectionist, but I want to get as much of the dust off as I can.

Should I use a liquid lens cleaner? If so, what kind? I don't want to damage or scratch the lens trying to get this dust off.

I can't believe dust that fine on the lens shows up so prominently in the picture like that even under those conditions. I live in a much dustier place than I thought.

It's a relief that it's not on the sensor. I should stop assuming worst case scenarios. It just seemed odd looking to me, then again, I come from a film background and I'm not used to HD or CMOS sensors, so forgive my ignorance.

Thanks again for everyone's help and suggestions.

[Alister Chapman]

I suspect it's the aperture your working at. Your earlier frame garbs are showing lots of diffraction artifacts which suggest the iris is almost closed. If you try to keep between F8 and F4 much of your dust will simply disappear plus the lens will be working at the apertures where it performs best. I wouldn't get too obsessed with lens cleaning. While it is good to have a clean lens too much cleaning could lead to a scratched lens.