Hi MIke
You write very little on what you want to do with the OM-5 and what improvement you want to get over your Pen-F.
I have bought an OM-5 at a good close out price this summer and am very pleased with it. I upgraded from an E-M10 (first iteration). I was keen on the Phase detect AF and was waiting for that to trickle down to the OM-10 line. These days it seems questionable whether there will ever be an OM-10, so I stopped waiting for the OM-10 V.
With the OM-5 II out, it is clear that a real update on the E-M5 III is years away, if ever. Comparing the OM-5 and the OM-5 II many of the differences are in my view minor. In favor of the OM-5 II you have:
- New menus
- USB-C
- Larger hand grip
The OM-5 has:
- Up to 10 Fps with mechanical shutter and locked AF, the OM-5 II only does 6 Fps
- External hand grip available, though expensive
- Compatibility with the Olympus mini-flash that shipped with the EM-5 ii, though it is not included where I am. I would need to purchase separately
I am using Olympus cameras since the E-300 and had Olympus/OM mFT bodies ever since. So I am used to the old menus. I prefer the external design (so called top plate) of the OM-5 and E-M5 III by a long mile over the OM-5 II. Together with the price advantage and the 10 Fps that swung the balance towards the OM-5. I felt I don't need the USB-C, since I have an external charger from my E-M10.
I use out-of-camera JPEGs a lot and often edit files in camera. I have my camera on JPEG + RAW and occasionally work with RAW files, mostly when I messed up the white balance. I think the image quality of the OM-5 is a substantial improved over the E-M10. The biggest improvement is the operational speed and the speed of the AF. Impossible for me to judge the improvement in operational speed and image quality over the Pen-F.
You ask about the E-M10 IV. That doesn't have phase detection in the sensor and uses contrast AF all the time. These days I need a fast CAF and I do not recommend anything that doesn't offer a phase detect AF, in particular not if it is just US$ 100 of a difference.
I got a set with the 12-45/4.0. I really love that lens. It does everything but speed. For that I have an array of primes ranging between f/2.0 and f/1.4. I use a 75/1.8 and 40-150/4.0-5.6 for my telephoto needs, depending on how much l light I expect on the project.
