barjohn
New member
I used Bob Atkins 4x6 test image chart used to test lens resolution to see how a few lens I have compare. I used his test setup and I printed 3 4x6 test images on 1 13x19 page with one in the upper left corner, one in the middle and one in the lower right corner. A multiplier of 25 times the sensor size works out to 17.21" x 13.28" so it was close enough for my purposes to use a multiplier of 25. I was particularly interested in the wide open performance of the Minolta 40/2, the Nikon 28/2.8 and the Nikon 50/1.8 in comparison to the kit 14-45 lens.
There is a high contrast set of test images and a low contrast set of test images. Since several of these lenses are full frame (35mm) lenses one would expect the edges to be very near the center.
Here are my results:
Minolta 40/2
F stop Location High Contrast Low Contrast
2.0 C 90 lpm 70 lpm
2.0 U 80 lpm 50 lpm
2.0 L 70 lpm 45 lpm
2.8 C 100 lpm 70 lpm
2.8 U 80 lpm 55 lpm
2.8 L 80 lpm 55 lpm
Nikor 28/2.8
2.8 C 90 lpm 70 lpm
2.8 U 80 lpm 62.5 lpm
2.8 L 80 lpm 55 lpm
Nikor 50/1.8
1.8 C 90 lpm 62.5 lpm
1.8 U 70 lpm 55 lpm
1.8 L 70 lpm 45 lpm
14-45 @45
5.6 C 90 lpm 80 lpm
5.6 U 90 lpm 70 lpm
5.6 L 90 lpm 70 lpm
@14
3.5 C 90 lpm 62.5 lpm
3.5 U 90 lpm 62.5 lpm
3.5 L 90 lpm 70 lpm
C = CENTER
U = UPPER CORNER
L = LOWER CORNER
lpm = Lines Per Millimeter
The Kit lens has a very consistent image across the frame
The surprise to me was the fall off on the full frame lenses. Anyone have any guesses as to why?
There is a high contrast set of test images and a low contrast set of test images. Since several of these lenses are full frame (35mm) lenses one would expect the edges to be very near the center.
Here are my results:
Minolta 40/2
F stop Location High Contrast Low Contrast
2.0 C 90 lpm 70 lpm
2.0 U 80 lpm 50 lpm
2.0 L 70 lpm 45 lpm
2.8 C 100 lpm 70 lpm
2.8 U 80 lpm 55 lpm
2.8 L 80 lpm 55 lpm
Nikor 28/2.8
2.8 C 90 lpm 70 lpm
2.8 U 80 lpm 62.5 lpm
2.8 L 80 lpm 55 lpm
Nikor 50/1.8
1.8 C 90 lpm 62.5 lpm
1.8 U 70 lpm 55 lpm
1.8 L 70 lpm 45 lpm
14-45 @45
5.6 C 90 lpm 80 lpm
5.6 U 90 lpm 70 lpm
5.6 L 90 lpm 70 lpm
@14
3.5 C 90 lpm 62.5 lpm
3.5 U 90 lpm 62.5 lpm
3.5 L 90 lpm 70 lpm
C = CENTER
U = UPPER CORNER
L = LOWER CORNER
lpm = Lines Per Millimeter
The Kit lens has a very consistent image across the frame
The surprise to me was the fall off on the full frame lenses. Anyone have any guesses as to why?