Thanks everyone - I've created one or two of these from panos before but this was the first shot with the finished product in mind.

Info:

18 K5 jpegs with Sig 10-20, handheld with plenty of overlap between frames. Stitched in PTGui, morphed in CS4 using basically this process with no other post-processing - even on the join The finished square crop is over 30 megapixels and I'm hoping will make a decent canvas.

If you're using free software then I'm sure Microsoft ICE and GIMP are more than capable of doing this.

Similar story with the Sigma 18-50 (now replaced by a 17-50 version) - both fly a little under the radar. Mine is excellent and with pseudo-macro function pretty versatile too. When bought (Aug 200 it was better priced than the Tamron, but a good copy of either is worth the upgrade from kit lens or 16-45 in my book. Not convinced of the benefits over the 17-70 though, often I'm left wanting just a tad more reach.

I'd only swap mine for something better and weathersealed, which leaves very little in the way of options...

I've done the RAC Rally three years in a row with no press pass and no problems getting superb access for photos - the beauty of most rallies is that you can get close to the stage and the cars as you're generally not fenced in. Common sense must be used though...

If you're looking to do the start/finish ceremonies then that's a different story, but catching the things in action is lots more fun!

Can't remember where I originally got the link, but there's a few potential tips in this free ebook: Good Photos in Bad Light

Exif is intact - I can see 'camera temp' listed, warmer than ambient but under 20 degrees?

Cheers Mike - sadly the Mrs came down with a viral infection last night so I'm on nurse duty for now, but itching to run some tests and get to the bottom of this. Hopefully just me being dumb and panicky!

Sorry, sensor hasn't seen a rocket blower, let alone a wet clean.

Alig, I'm pretty sure the eyepiece was covered with thick black cloth when I set up down by the lake - it was part of the process I realised I'd missed down by the coast. Did you get consistent patterns regardless of setup?

A quick bulb mode test with lens cap on and eyepiece covered (in warmer conditions than weekend!) seems okay, I'll run some more outdoors when I get a chance and report back - probably be a few days.

Haha, great moment!

Yves, I cleaned the B+W ND110 and used a different ND grad between shots, in addition to changing location, lighting direction, sensor orientation etc. Reflections would surely have changed, yet those marks remain consistent?

Neither can I, it just struck me as a variable between the car and landscape images, which used otherwise comparable settings. I'll do some more testing the next few days including filter on/off, with lens cap on, cable/IR release etc.

Understood, I'd feel the same and certainly not trying to be alarmist here - mods feel free to take the thread down if that's how it appears - just looking for some sensible Pentax User suggestions. If I was looking to create hysteria there are 'better' forums for that

Cheers John, I'd seen the Sony heating issues but that seems to be triggered by extended use of video/live view, especially with SR on.

I've used the same lens/filter combo before now with no issues (other than the Cokin cast!) so don't think it's that - in fact I've even used it on the K5 for similar exposures:




Thinking about it I used a cable release for the car shot but that broke - these were the first using IR remote. Will get another cable release and do some more testing, but gut feeling isn't great on this right now