here's a comparison

 
Since all my Pentax lenses would shoot wide open, here's a tripod shot using the Vivitar 28-105 at 105mm f/5.6 to compare with the 45-200. That shot was taken an hour earlier and at 97mm (gosh what precision!), so apples are compared but like Granny Smith to Gravenstein. As noted in other posts, the Vivitar/Kobori 28-105 continues to show itself as a very nice lens!

comparing the Lumix 45-200..

I'll need to use a tripod to compare this lens, as lack of OIS will bias against alternatives. This lens does great work (as advertised), and it's a bargain too (also as advertised!). I have a line in for a micro-Zuiko 40-150, no IS for Panasonic cams but very small and light. We'll see how it does.

comparing 18-55WR and 16-45

I had a chance to make some rather hasty tests of these two Pentax lenses. Taken at f/5, and shot to match exposures, the conclusions are expected: the 16-45 shows better resolution near the edges but both are similar near the center. This Picasa collage isn't intended for deep inspection, just shows that both took a nice image overall. So other than weather-resistance and range the general results are pretty similar.

 

curious timing (2 lenses)

For the 1st and presumably last time ever, I received two lenses on the same day - for two different camera systems! I actually had the 45-200 Lumix in hand for a while, but my wife commandeered it for a birthday gift. On that day my Pentax 18-55wr arrived at last. It should have arrived three weeks earlier, but an inferior 81-55 DAL came instead; after shipping it back (for free) and talking with the company, my WR is now here. Too late for the planned fourth-anniversary trip, but the weather was so poor we didn't go outside anyway so no big loss. I never thought I would own two interchangeable-lens systems at one time, so the odds of receiving a micro-4/3 and Pentax lens on the same day will be quite small!
Now for a mess of tests..

realignment for 2011

I've been trying to dispose of some PK manual lenses for a while, and it seems a few are about to move. I saw a 45-200 lens for the G1 at keh.com, and offered them a few items that combine to a similar value, so the G1 system will soon cover the 35mm equivalent of 28-400 (the Pentax does 24-450). In neither case should I be playing with anything over 200-250mm equivalence, not without tripod or monopod.. but they're available if I feel lucky. I'm quite happy with the Pentax' 50-200WR and may let the 55-300 go soon; if the 18-55WR tests well I might contract to 27mm equivalence for the weather resistance. We're planning to take a short anniversary trip in a few weeks, so it will be nice to get out and play.. even if the cameras stayed home that would be true!