Puzzled Lens Testing - m43 lenses on e-m5

Corpy2 wrote:

A few days ago, with a friend I ran a series of tests comparing my friend's Olympus 14-150 on his e-m5 against various lenses on my e-m5.

We shot the same shots at distances of minimum 50 to 300 feet or so, targets with lettering. Each shot was only in raw,

Completely useless to shoot RAW and then try to judge MTF (resolution, microcontrast) on the camera. What you actually looked at was very low-quality jpegs embedded in the RAW files.

Precisely because the jpegs embedded in the RAWs are too poor for good in-camera review, I regularly shoot RAW + Fine jpeg where the jpegs are used for in-camera review only.

But if I want to test lenses, I would of course not use in-camera review at all. I would open the RAWs in the RAW converter. Of course, I would also use a tripod unless the shutter speeds are way above the safety limit with regard to camera shake.

In short: No wonder you didn't see much of a difference under the testing conditions you chose.

handheld, at identical f stops (the largest f stop that was common to both--the limiting factor usually being the Olympus 14-150 smaller maximum apertures). The ISO chosen for both was the slowest that was consistent with conservative shutter speeds of at least 1/500 or faster. Usually, this meant, on a cloudy day, ISO of 400 or more usually 800. Since most of the lenses were fixed, the shots were zoomed for the 14-150, of course, at the mm of the fixed lens on the other camera.

The lenses tested were, again, the 14-150 on his camera, vs. the following on mine:

1) 20mm f 1.7

2) Panasonic 25mm f 1.4

3) Panasonic 45-175

4) Olympus 75mm 1.8

5) Olympus 45mm 1.8

I did not compare the shots on a computer screen (or, God forbid, printing). Rather, after shooting, we first checked that the frame for each shot was roughly identical, and then magnified on the camera screen the shots taken to maximum magnification and compared for image detail, one lens vs. the 14-150, lens after lens.

I was surprised that, except for the shots with the 75mm, upon comparing the images there was no noticeable difference in detail captured in the images! Only the 75mm images had more detail, but really only somewhat noticeable at maximum magnification. All the other comparisons suggested that it mattered not a whit if the shot was taken with a, for example, 20mm 1.7 or a 25mm on one em-5, or the 14-150 on the other set to the same mm.

I find these empirical observations difficult to understand. The only thing I could think of was that my friend's 14-150 was fortuitously the best sample ever made of the 14-150, which is unlikely. Can anyone suggest what I might have done wrong, or a different way of objectively testing which would have yielded results closer to what I strongly believed would be the case--that the fixed lenses would result in images with far more detail?

Thanks.