28-135 IS Tests

I just received a used 28-135 IS lens from a right nice fellow on Astromart. He stated that the lens was the sharpest of 3 that he had gone through to get to this one. Grain of salt applies, I guess, but I have dealt with this gentleman on Astromart before and he has given me no reason not to trust his word. I decided to see how it stacked up against my 17-40L and 75-300 IS.

I'm not a big fan of 100% crop comparisons, so I did an 8x10 printout of the 28-135 image @ f/3.5 and an 8x10 of the 17-40L @ f/4 (both at 28mm) and the difference was obvious. I didn't print any others.

I took the images inside of a basket from 10 ft. I used mirror lockup with an RC1 for a trigger. Here's the comparison at 28mm to the 17-40L. The image on the left (top) will always be the 28-135 IS and the one on the right (bottom) is the reference image.

28-135 @ f/3.5, 17-40 @ f/4

both @ f/4

28-135 @ f/5.6 17-40 @ f/4 (I left the 17-40 @ f/4 as my baseline image)

28-135 @ f/8, 17-40 @ f/4

Next, I compared the 28-135 IS to my 75-300 IS @ 135mm. Interesting that the TFOV on the 28-135 @ 135mm was smaller than the 75-300 @ 135mm. Makes for a weak comparison. Data presented for prosperity. Again, 28-135 on the left (top) and the 75-300 on the right (bottom).

The comparison at f/8 was interesting because I thought the 75-300 got worse at f/8 and the 28-135 got better.

My conclusion is that the 28-135 IS will not suit my needs for a walkaround lens unless I always keep it at f/8. I will try that and see if it works. My walkabouts are always outside, so maybe this will work out.

Another conclusion is that the 17-40 is one fine lens.

I have an 80-200 2.8L zoom on the way that should establish a tough benchmark for the 28-135 and the 75-200.

Here is a focus test shot done at 28mm, f/4, at a 30 deg angle (60 deg from perpendicular) to see if it was focusing properly.

28-135 at 28mm, f/4

17-40L at 29mm, f/4

Almost looks like the 17-40L focus point is off. This lens testing stuff is hard.

UPDATE: I have taken a bunch of pics now with the 28-135 IS and it is winning me over. As a matter of fact, it just snapped my best pic so far (of about 2,000):

A little Noise Ninja for the ISO400 setting and a little color saturation. This is at 75mm, ISO 400, f/5 (wide open), 1/125 sec. Here's a 100% crop:

Below is the full TIFF if you want to play with it (the thumbnail is a 900k JPEG, the link is an 18 Mb TIFF)

18 MB TIFF