Zooming in on the Moon

How much detail can you see in the moon with a compact Olympus 75-300 zoom lens? Here is my attempt from tonight using 190 separate images stacked in Autostakkert and with basic sharpening applied. It helped I figured out the camera wifi and got the shutter triggering remotely from my iphone.

I don't think there is much more detail possible at this focal length and pixel size (maybe somebody can prove me wrong!)

Camera Settings

Sigma 170-500 version

Using a borrowed Sigma 170-500 Zoom adapted to the same camera here is the moon the following night. Although the moon appears the same size here, the extra focal length clearly shows improved image quality. I will definitely be looking out for this lens on the second-hand market (or the newer version which reaches 600mm). However, this lens is far less portable and too heavy to take on a hike :(

Camera Settings