Oly 100-400mm vs. Pana 100-400mm - quick and dirty sharpness comparison

Out of curiosity and for the sake of completeness, decided to repeat the comparison in a bit more controlled setting. I guess there are more useless things to do to fill a rainy and grey Sunday morning. Possibly.

Test setting

- Same silly target on a roughly 3m distance, artificial light used

- Pana G9, tripod mounted, e-shutter, operated remotely with Pana Image App

- AF-S, dual IS (Pana) / lens IS (Oly) OFF, 400mm, f6.3, 1/640s, ISO400

- 5 consecutive shots taken with each lens, images "assessed" by eyeballing

- RAW, imported to LR, no tweaks

Samples images below (only posting one each as the 5 shots taken seemed consistent.

Oly:

Pana:

My conclusion: images taken with Pana "appear" to me still just a notch sharper, but the difference is very, very minor. This probably does not even translate into a noticeable difference in a real life shooting scenario (the stabilization effectiveness difference might though...)

Of course this is not a conclusion that one is sharper than the other by design but only shows the difference between the two specific samples that I currently have in my hands. In the past I've also tested another Pana sample and there was a more significant difference than between these two. Damn sample variation!

Having now handled the two lenses for a couple of days, summarizing other observations:

- Magnification on at least short distances seems a bit different at 400mm, Oly being a bit longer (did not quantify the difference though)

- Pana dual IS feels significantly more effective than the Oly lens IS, judged how well I could keep a distant target within a small focus area (did not do any real quantification). Dual IS is a real marvel.

- Oly is larger and heavier, but not significantly so in my view. Both fit well with my shooting style (and my camera bag), but something to consider anyway

- Having put on the Oly lens on G9 a few times, I realize how much "looser" it sits in the camera mount. There is some rotational play which you don't really notice with Pana as the lens fit is tighter. With Oly you feel and hear the play clunking when you rotate the zoom. The play in axis perpendicular to the image plane also feels more pronounced. There is of course a spring on the camera mount side that should force the lens towards the camera but the lens being heavy, not sure if this is really the case. Tested it also on my G85. It feels roughly similar to 40-150mm, which I used to have. Perhaps this is just the way the Oly lenses behave in Pana bodies due to different mount tolerance set up? Perhaps again not a real life concern

I'm still a bit on the fence whether to keep the lens or not. My main motivators for getting it was a faint hope for just a bit more sharpness and the ability to use TC's. Seeing though how the sharpness and IS compares, it might be a bit of challenge though to get decent results with 1.4x.

Anyways, might still take the lens out to meet the birds if the weather improves in the afternoon. Goldfinches and greenfinches have been reliably around in the local nature reserve so perhaps they will lend a helping wing for the decision 

Marko