150mm - 180mm Mid-Telephoto Lens - Infinity Test #2


The area enclosed by the red box is represented below at 100% magnification. No sharpening, color, or contrast adjustments were made. I focused on the yellow street sign with the 4-way intersection mark (looks like a + sign) at the bottom of the cropped image.

This time I used the same compendium shade on all of the lenses. Since the previous test, I also affixed a baffles to the inside of my Pentacon 6->Canon EOS adapter and flocked it to reduce internal reflections. This appears to have paid off, resulting in somewhat contrastier images. However, the Pentacon mount lenses still exhibit lower contrast at F22. I think this can be attributed to the much larger cone of light that the lenses project (compared to 35mm lenses) and the use of the adapter.

See notes on the limitations of this test at the bottom of this page.


Wide open
Canon lens at F5
180mm Sonnar at F2.8
150mm Hartblei at F2.8
150mm Kaleinar at F2.8
150mm Tele-Xenar #1 at F4
150mm Tele-Xenar #2 at F4



F8
Canon lens
180mm Sonnar
150mm Hartblei
150mm Kaleinar
150mm Tele-Xenar #1
150mm Tele-Xenar #2



F16
Canon lens
180mm Sonnar
150mm Hartblei
150mm Kaleinar
150mm Tele-Xenar #1
150mm Tele-Xenar #2




Some limitations of these tests:

1) Point of focus. This time I focused all lenses manually. Viewed at a pixel-level, it appears that the focus on the Kaleinar is not accurate.

2) Air disturbance. Well, this is a real world test. I shot these images at around noon on a sunny day. It seems that heat waves in the air may have distorted the images somewhat, especially lower to the ground as is visible when looking at the yellow street signs at the bottom left. Looking at the vertical store signs on the upper right side of the image may provide a better gauge of these lenses resolving power.

3) Contrast. Probably due to the Pentacon 6->Canon EOS adapter, and particularly at smaller apertures the Pentacon lenses exhibit lower contrast than the Canon zoom lens. Since the previous test, I affixed a baffles inside of the adapter and also flocked it to reduce internal reflections. The difference between shots taken before and after my work on the adapter is noticeable, but probably wasn't enough to completely kill all internal reflections.

4) Representative sample. I am using my own equipment for these tests, some purchased new but other pieces purchased used. I do not know the history of the lenses I purchased used, and so some of them may have been disassembled or serviced prior to their coming into my possession. At any rate, the lenses tested here are assumed to be a "representative sample" of what is commonly available. Variations in manufacture among other things may skew the results, and so these test images may or may not accurately reflect what you can expect from a different lens specimen.


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All text and images Copyright © 2004 - Kevin Ing