70-210mm supertest images: Conwy Castle.

Pentax K5, 70mm, infinity focus, 100ASA, auto WB, manual mode.

This is a classic view of the castle from Benarth Hill to the south, however not that many visitors make it to this side. Most are shooting more into the sun from the estuary or town. I chose a nice sunny day and set up the tripod in the shade of some trees.
One K5 idiosyncracy I noticed on examining the images is that the pentax, unlike the samsung, does tweak internally the white balance to suit each lens. This is how temperature and tint were reported for the RAW files in LR3.6 for each lens (temp: lower values cooler = bluer; tint: lower values = more green, higher = more red):

Lens	19AH	52A	kiron ZL	VS1-kiron	VS1 tokina	VS1 komine
temp	5000	5600	5250	5050	5000	5200
tint	18	15	14	15	19	13

Significant differences. The effect of this is to tend to average out the colour differences between the lenses. I did in fact nudge the more outlier values back towards the mean so that the colour differences between the lenses became more evident. The only other PP I did was some negative exposure adjust to get consistency, a little recovery (clipping on the white flags) and spot removal.

Click on the thumbnail on the left or drag on the crops below to view different parts of the image. Use the dropdowns to select the lenses and the buttons below them to select the apertures for comparison. Image sizes ~3.5MB, allow time to load.