Hi, so, I created a lot of confusion. I'll go through the individual messages. In a second post, I'll provide an example of what I mean
Originally posted by séamuis you absolutely should which makes this whole thing rather bunk to be honest because at f11 what lens isn't sharp?
I know the DoF is razor thin. That wasn't my point. At f11, no lens is really sharp because of diffraction (max. resolution is about 7.4 microns which isn't even enough for true 1:1 on the K20D).
Originally posted by Nesster Also, the resolution numbers aren't directly comparable between cameras, so the Canon numbers won't match Pentax, and neither will match Nikon, and so forth. I see you applied some sort of correction factor, maybe that helps.[...]false accuracy
I know about the false accuracy. I used the lens data in boldface to calibrate across mounts. This isn't totally correct but the best I can do. Fortunately, some lenses were tested for multiple mounts and I used this for my calibration.
Originally posted by jsherman999 Viv 105, FA 50 2.8, DA 35ltd, Sigma 70/105/180, Tamron 90, VL 125.
I already own a DA35 Ltd. Great lens and it really gives 1:1.
The point which I didn't get across: I want to go further down, up to 10:1 which is were the lights finite wave length would stop you
Originally posted by thePiRaTE!! What he's saying is that scientifically speaking, a lens that is sharper at 2.8 than f4 is capable of better resolution and was analyzing the ratios on that basis. By taking the lenses with the highest mean scores and then checking that ratio he's just sorting which one theoretically could be the highest resolver of the bunch.
I do wonder though along the lines of what others are saying, if aperture wouldn't negate a lot of the advantages of a top resolving glass and even out the field?
Yes. The lower the aperture of max. resolution the better the lens. This is a universal law and true across mounts.
I don't plan to stop down the lens. This isn't possible anymore if you go beyond 1:1. You have to use the best resolving aperture and use focus stacking in software, i.e. dead subjects.
Originally posted by ghost maybe I'm just being naive, but all of the lenses are in the same area (2100/2400).
photozone.de figures are limited by the sensor resolution. E.g., Pentax K10D is limiting figures to 2592 LW/PH, because this is the sensor's no. of pixels. All the lenses I mentioned are far beyond the sensor's capabilities and therefore, even small differences can mean huge resolution differences for the lens.
Also, I don't mount the lens to the body. I reverse-mount (front to front) it to another lens, e.g., a 50mm to a 300mm. The 300mm will magnify 6x and give the K20D a 0.8 micron sensor, so to speak. What resolves good on a 5 micron sensor (K20D) may resolve badly on a 1 micron sensor. Which is why I need such a perfect lens to go beyond 1:1. And by doing so, I continue to operate both lenses in their designed way, namely at infinite focus.