There was a recent post dealing with extra reach that the K-3 provided with his/her DA*300 lens. I have the DA*300 and the Sigma 150-500. While one outing doesn't prove anything I went out today to Conowingo Dam in Maryland to shoot eagles. The 300 outperformed the 150-500 in terms of detail at about the same distance. Obviously I need to do more testing. I've been limiting the Sigma to 400mm because going to 500 provided more reach but an image that I felt was degraded in quality. Looking at the photos I took today, in cloudy overcast light, the images I got from the DA* 300 provided better detail than those taken with the Sigma 150-500 at 400. These were of birds at approximately the same distance. I feel the extra resolution of the K-3 may bring out more from the 300 whereas the K-5 I was using already maxed out the 150-500. One day, a couple hundred shots, actually 1300. But I need more experience.
On this shoot I consistently got in focus sequences of 20 or more shots of eagles in flight at different flight paths - going horizontally and coming toward me. I never achieved this with the K-5 - getting a couple out of 20 in focus was good.
SO for those with high quality lenses, I am guessing you'll get a lot of extra performance from those lenses to go along with a quantum leap in auto focus performance from the K-5.
So the hunt is on - how to sell my wife on a good 500. I would be interested if those shooting with the Sigma 500 find the a similar perceived bump in lens lens performance.
Last edited by RockvilleBob; 11-21-2013 at 03:19 PM.