It’s been one year that I’ve had the HD PENTAX-DA 55-300mm F4-5.8 ED WR and I am still very pleased with it. For the money it is a very good lens and the weather sealing has been a definite plus for me.
It’s minor weak points seem to be an increase in softness and chromatic aberration as you move away from the image center towards the corners and it’s slower aperture at the long end (f5.8) but all things considered it does the job and provides photographic freedom for creating images. The distortions seen in the corners are at their strongest at 300mm and require stopping down to about f8.0 to make an appreciable difference. So after a year of use I would say unless I need f2.8 or some improvement in image quality I tend to take the lighter DA55-300 with me over the DA*50-135 because of its greater versatility and lighter weight. You can see my user review for it here HD PENTAX-DA 55-300mm F4-5.8 ED WR user review and some other thoughts here HD PENTAX-DA 55-300mm F4-5.8 ED WR and the rest of the kids. If I needed to I would buy it all over again.
Bellow are 100% views of some test images I shot. I created and printed a chart specifically to test the performance of the lens.
While I didn’t set the test up with extreme rigor it demonstrates my points and matches my findings in real world situations. The first image bellow is from the center of the HD DA55-300 ED WR at 120mm. You can see that when used at its widest aperture for this focal length the image is somewhat soft and with chromatic aberration showing up as purple fringing. Stopping the lens down to f9.0 decreases this type of aberation leaving primarily transverse aberations as seen by the red fringe on the now sharper image.
It should be noted that with some minor processing the chromatic aberations can be greatly reduced and further adjustments can yeild a superior image as seen in this before and after. Again taken from the center of the frame, now at 300mm but still with a wide open aperture of f5.8
As I mentioned previously the image corners suffer the most when it comes to distortions. The image that follows is taken from the upper left corner with an aperture change from f5.8 to f10 and no further processing.
Here for comparison purposes is a central crop from the DA*50-135 and the DA55-300 both at f9.0 (The camera was moved to provide similar framing) You can see that the DA* 50-135 is sharper and less distorted.
But with a little processing on images from both lenses the playing field is leveled slightly between them.
The image above is from the center of the frame where the image bellow is from the lower left which in the case of my lens seems to be the worst of the corners.
All this should be taken with a little bit of a grain of salt however as these are 100% crops from the demanding 24mpixel Pentax K-3 under more extreme conditions than the average picture is taken.
(The salt picture is taken with the DFA100 WR macro as the HD Pentax-DA 55-300mm F4-5.8 ED WR does not lend itself to this type of image making because of its maximum magnification of 0.28X)
It’s certainly not my intent to leave the reader with a lingering sense that the lens is weak. It’s actually a good lens optically and you are going to have to pay for any improvements either in limiting yourself to fixed focal lengths or by paying more money or both.
Here are some more images from the past year taken with this lens and the Pentax K-3 with a few cameos from the K-01 mirrorless.