Aperture should cope with JPG & DNG (it may not cope with K20D PEF files though).
(And you may find there's an update to Aperture to handle the K20D PEF format anyway - there are always new RAW formats appearing!)

If you've shot in PEF, do not worry! Just download Adobe's stand alone DNG converter - this can take all your PEFs and convert them into DNG. Aperture should cope with the DNG files

...but maybe a Mac user can confirm!

Matt

LOL!
Matt

You work like this (with the camera in AF-S mode):

1. Put camera on tripod
2. Get a decent test target
3. Set the lens to either maximum or minimum focus point
4. Autofocus and take a test shot
5. Examine at around 11x magnification on the LCD
6. Adjust the AF if needed
7. Go back to step 3 and repeat until satisfied.

HTH!
Matt

John - it's only one of the DA* lenses (the 50-135). I'll definitely keep you posted! The DA17-70 has been brilliant! It's almost supplanting the 50/1.4 in a lot of situations
Matt

Check out this link - https://www.pentaxuser.com/forum/topic/Ned-Bunnell-Blog-11690

Thought this might be worth reading:
Op-Ed thoughts by the sea

also (linked from the article):
Ten Recommended Cameras

As the article says:
My view: Will my photography improve by switching brands or to FF? A little perhaps, but not in proportion to the extra money

Will my photography improve by using the DA* lenses? I'll keep you posted

Matt

Just getting (slightly) back on topic...

I've been getting into the deeper side of ArgyllCMS and it seems to have resolved pretty well all the colour issues I was experiencing
(FWIW, ArgyllCMS is available for Windows, Linux, and Mac!)

There are two ways of creating a display calibration - either matrix/shaper or cLUT. The normal and easier method is matrix/shaper - but this yields pretty dire results if the display doesn't have a decent black point! If you calibrate with the cLUT method, and the applications you use are cLUT-aware (e.g. Silkypix, Photoshop, etc) then the difference is worth the effort. I now have the Tosh M200 tamed.

That said, the Dell RGB-LED display (not the White-LED) looks pretty awesome

Matt

Aiki,
You won't (generally) see any difference in GIMP (or Photoshop). These are colour managed applications.
The problem comes when you save an image for he web (or to email to someone) and they are not colour managed. Most applications assume the image is in sRGB. Consequently if you save an AdobeRGB image and they open it assuming it's sRGB the image will look very washed out and pale.

AdobeRGB can handle a wider range of colours compared to sRGB. I usually work in AdobeRGB and then convert to sRGB before saving for web or emailing
Matt

Thanks guys Bit the bullet and called Chris.
I should know Thu/Fri how it works
(I'll report back!)
Matt

Mike - I knew there was no aperture ring. Thankfully I have Triplus tubes with full contacts
John - will let you know what happens!

It's interesting that with the DA17-70 the Tamron 70-200/2.8 looks a better match. However, the sheer weight and size of the beast (though not as much as the Sigma) really puts me off. Even the 50-135 is a touch on the big side - but discrete enough to get away with I reckon
Obviously the longer reach between 135 and 200 would be nice... but not at that cost in size! The Tamron with hood is certainly "bazooka" like for handheld!

Matt