K5 Sensor Issues...

Have you actually taken a shot of featureless wall at small aperture and cranked up the contrast on the result?

If you have, and you've got no dust, I'd love to know what's special about your lens change technique.

I had to butterfly my K-5 for the first time a week or so ago.

I have had to clean my K-5 twice since I got it. I don't see it as a problem.

It's a lot easier to deal with sensor cleaning than to spot prints. White spots on darkroom prints were a nightmare.

Did they come from specks of dust on the negs?

I get lots of white spots on scans if I don't have Digital ICE switched on.

Black dust on negative = white spot on print. It can be dust that adheres to the film during drying and the drying needs to be in a scrupulously clean area. A shaft of sunlight in a room reveals just how much dust is around. Negatives should be cleaned carefully prior to avery use, including scanning.

There are microfibre cloths, up to very expensive antistatic vaccum devices.

Life's way too short for that, if you have Digital ICE on your scanner

I know what you mean, it's a slow process at best, but Digital ICE will not see detail that is covered by dust. It's in a way like cloning everything in sight rather than cleaning the sensor.

For a quick scan that's one thing, but to do a high quality job then that's something else. It's why I rarely scan. It takes too long unless it's really needed.

I bought my K-5 in March (I wish I'd bought one of those posh lenses at the same time, having seen the subsequent price hike). Anyway, after about a month I noticed a circular blob appear on the upper right hand side. It doesn’t vary with lenses or focal length. It doesn’t show up by the Dust Alert function.

I'm new to DSLR so am not familar with what dust looks like. Does this look like dust, or is it the dreaded sensor stain? Or could it have be caused by condensation? Whatever the cause I feel unlucky to get such a problem so soon.

Click here to see the blob. Note it's actually the photo I submitted for the 'Tree' competition, only I've increased the contrast a bit to make it more obvious. BTW, that white speck lower down is a genuine UFO, not dust!

That is dust Charlie. You can clone it out for now but you will at some point need to clean your sensor. I suggest you invest in an Arctic Butterfly brush. They are not cheap but they do a great job and last a lifetime.

When you change lenses make sure you keep the camera pointing down, to minimise the chances of dust getting in. It takes a bit of practice but soon becomes second nature.

Thanks Gwyn. I only swapped lenses a few times in that time and thought I was being careful. However, a normal domestic environment is far from dust free and it's impossible to ensure dust doesn't get in. I'm also careful to immediately pack the lens cap because if that gets dusty it can move to the lens and then into the camera.

I was wondering if it was a condensation blob because I first noticed it after going out on a cool evening. I don't want to invest in an Arctic Butterfly to deal with a condensation mark!

I have never had trouble with condensation and my camera has been in and out from a warm ship to Arctic temperatures and back. I think you'll find it is dust.

Try running the cleaning program on the camera first, before spending money on cleaning.
If it doesn't annoy you too much then just clone it out for now, and wait till you spot more dust, or get annoyed with it before cleaning.

Do you mean run 'Dust Removal'? I've tried that. Isn't that run everytime I turn on anyway? Or is there something more sophisticated?

Thinking about it, if it were a condensation mark I assume they'd probably be more than one of them.

My main concern was whether it was a 'stain' which I should get fixed. I'll just learn to live with it for now, as you suggest.

It isn't stain. That problem has long since been fixed, and it looked very different to what you have there.

dammit! I've just joined the group so I can express my frustration with a similar problem with my k30, just posted my entry and then read this!
do we have a common problem perhaps?

One more thing......the sensor has a static charge even after switching off the camera, so best to wait some seconds after switching off the camera before changing lenses to allow the static charge to dissapate.