There's a
previous thread wondering about the DA 35 f2.4 and DA 18-135 at 35mm, but I'll start this one since I'm comparing my whole lineup of lenses I have that shoot at 35mm.
General comments:
I realize that simply comparing sharpness at 100% center crops is not the measure of a lens. A lens' ability to render contrast and colors is important in apparent sharpness. A lens is also evaluated on its sharpness across the frame, distortion, bokeh, ability to focus, price, convenience of a zoom vs. prime, and speed. Together, all these factors go into a lens' IQ or quality.
I did find that lenses also evaluate light differently. The DAL 18-55 consistently underexposed, the DA 18-135 somewhat less so, and the F 35-70 somewhat more less so. My samples show them with minor level adjustments.
All pics were taken using a K-30, fixed ISO 400, and a timer (so no shake reduction). Focus in every case was on the little emblem above the T in Bertolli. Distance was about 2 feet, so even at f2.4, I had almost 2 inches of focus range. I shot at wide open for each lens, and then at f3.5, f4.5, f5.6, f8, f11, f16. I used Av mode, so the shutter speed was changing in each instance.
Broadly speaking, the DAL 18-55 was the weakest lens, but it really is still a quite decent lens. Even viewing full screen on a monitor, the pics look just fine. It's only when you compare it to the other lenses at higher magnification that you notice a difference. So, in the comparisons below, I've omitted the DAL 18-55.
Also as a general observation, the differences between the lens lessened as I closed down. When you get to f8-f11, you can still see some differences at 100%, but there isn't much.
SUMMARY:
The DA 35 f2.4 was the best lens at every f-stop. At f2.4 it was even better than any other lens at their wide open stops of f3.5 - f4. Contrast was great. Bokeh was nice at every f-stop. Lens looks pretty sharp with negligible distortion across the frame. There was minor CA at f2.4, but it was gone by f5.6. I like that it is small, lightweight, and fast. It really is a great little lens. Indoor or outdoor, if I'm shooting at 35mm and quality is most important, this is the lens I will use.
The next best was the well-regarded Pentax F 35-70, especially from f3.5-5.6. Small, f3.5 at 35mm, fast (but noisy) focus... It's only a 2x zoom, but 35-70mm is an often used range. If I want a bit more flexibility than the DA35, this is the one I will use.
The next best was the Tamron 24-135, and it was even better than the F 35-70 in the f8-f16 range. The quality from this 5.6x zoom is really excellent. I'd use it more, but it is fairly large and heavy, and if I'm going to use a walkaround zoom, I like something wider. This is a full-frame lens, however, so if Pentax ever comes out w/ a FF, this will be a fantastic lens to use.
I was disappointed that the DA 18-135 consistently ranked 4th in my tests. This is the lens that is usually on my camera. It's lightweight, focuses quickly and quietly, and has a very useful zoom range. All that and it's WR as well! Differences in quality between this and the other lenses are small enough that I am still very happy to use it as my general purpose lens.
I'm only providing a few examples of the pics. There is EXIF info on the pics below, but they are organized as:
DA35 DA 18-135
Tamron24-135 F 35-70
1) This is 100% center crop of each wide open. Even at f2.4, the DA35 is sharper than the others.
2) This shows the scene I created. Pics are all at f8. I did adjust the levels a bit on the DA 18-135 and F35-70.
3) 100% center crop at f8 of #2.
Originally posted by JinDesu 
Post #1 by mgvh
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