>>3396373Took this a while ago for sharpness question someone was having. First one is prime zoom kit lens. The other one is 25mm prime. Mid tier price range lens for m43. It's same location. same light, both are using same aperture, and same focal distance.
You're making some very complex questions. Answers aren't straightforward and will depend from system to system a lot. Even from lens to lens. Modern telephoto zoom lenses tend to be very good compared to old telephoto lenses. Technology advancements in coatings show here the most. Modern primes not as much, but there are exceptions everywhere. You have modern primes that are sharp as hell, but offer lousy bokeh. Old primes that are fantastic overall lenses, but flare like crazy. Modern zooms that have fantastic bokeh, but are not sharp. There are endless possibilities. Once you know what you're looking for you will be able to decide on your own.
Iso is different story. For best images, you're always shooting at lowest iso. Even for night, low light photography. You shoot lowest iso, use tripod, then extend shutter time. You go for higher isos when you aren't as interested in best quality. Top end stuff is always shot at base iso. Cams are in fact optimized for that base iso. There are extremely rare cases where a cam will have two base isos. gh5s is in fact only one that I know, and it's niche camera designed for video. Everything else are extension isos.
It appears to me you've read a lot on the stuff, but are quite ignorant on how it all comes together. I'd advise you on buying some very cheap option first. Some used dslr or mirrorless kit, then spend half a year on it. You'll invest little in system, so you'll easily be able to drop it and move to something else when you figure more precisely what to expect from other options. Sales like this aren't doing much for prices. You won't find a killer deal. Prices drop all the time, and you can get quality used gear for fairly cheap.
