No shame if it's not as you expect, it's just that dust has never encroached on you pics, and undoubtedly your methodical and careful lens changes will have helped enourmously there.

I on the other hand are often in the middle of a windy meadow, or grubbing around in the dirt, so I can only expect dust to be evident now and again.

Dan

John, I still find it amazing that you've never had any dust on your sensor. I'd be really interested in seeing a pic of a blue sky or white wall at f/16 or f/22 to see how dust free 'dust free' is for you.

I wouldn't say I've ever really had a problem with dust, but I do get dust on my sensor. I've found the K10D cleans up much easier than the *istD, with just a quick few blasts of the rocket blower rather than the sensor swabs I used to use.

Dan

So that's what he's doing these days.

Dan

No, that would be correct, if the spider was 4mm across it's legs.

However, this is a shot I just took with 3 extension tubes and the 50mm f/1.4...




The width of the image shows about 17mm, so slightly under 1.5:1 magnification. Assuming you have similar sized tubes, either the spider was bigger than you remember (4mm body + legs?), or you have super long tubes, or you have a macro 50mm lens.

I tried reversing the 50mm lens, and got this:




...so much less magnification (less than 1:1.5) than with tubes, as Chris said.

Dan

Hi Lilly,

It's very easy to see how close a reversed 50mm lens will get you, just hold it round the wrong way in front of your camera and see what the view through the viewfinder is like. You'll have to set the aperture with the ring on the lens, and have the camera in manual, but you can at least try it and see.

You'll have to move the camera backwards and forwards to focus.

A set of three extension tubes would give you approximately 1:1 magnification with a 50mm lens, but with the result that your subject will be about 25mm from the front of the lens.

Dan

Are you talking specifically about Sigma aspherics, or just lenses with aspheric lenses in general?

You'd be fairly hard pressed to find any modern zooms that didn't contain one or more, including the new DA*s.

Dan

Not seeing an awful lot of Pentax stuff on there...

Dan

Pete, if you scroll down that page a way, you'll see two other stories.

The first says that during one week in July, the only DSLR to make it into the top ten best selling digital camera list in Japan was the K10D. Canon/Nikon/Sony/Olympus didn't make it. Another huge success for Pentax, and it just goes to show why this comparatively small company might be having supply problems.

The second says that Nikon sold more units than Canon during the first half of 2007, with Pentax in third place. I'm smiling 'cos Canon were second.

Dan

I use this lens and it's wonderful - I wouldn't be surprised if that auction tops £200 though...

Dan

I say anything goes until the closing time!

Enjoying it all so far...

Dan