Test: cropped Zuiko 75mm 1.8 better than a good consumer zoom (Lumix 45-150) from 75 to 150mm

I have just purchased the Olympus 75mm 1.8 and, although I got it brand new for a cheap enough price thanks to grey market imports, it's still £495 and my goal these days is to go for less lenses, of better quality and preferably not spend much money. Thus I might sell my 45mm 1.8, which is now a bit redundant between the 75mm and the long end of the 12-40. I will also probably sell my Panasonic 45-150. However I wanted to check in a kind of "scientific" way wether or not I'll be losing reach by doing so.

The idea basically is that if the 75mm is significantly sharper than the 45-150, I might be able to get similar magnification by cropping pictures and upscaling them.

Let's see how the comparison went (all pictures shot with an om-d e-m5 @ 400 iso).

Test scene @ 75mm (* compared side by side at 100% at the end of post if you're interested)

Side by side general view

Test scene with the Zuiko @ 75mm and the Lumix @ 150mm:

These are the pictures that will be used for the comparison

Now, in oder to be able to proceed to a fair comparison @ 150mm, I've produced 2 jpeg files from these 2 test shots in the following way:

With the 75mm: picture cropped at 50% and upscaled as a jpeg to the size of the original picture (Lightroom export with output gain set to "normal")

With the 45-150: Lightroom export with no resizing and gain set to "normal"

Side by side comparison @ 150mm equivalent:

At 50%

At 100%

It appears quite clearly that, for the same final perspective, a 50% crop of a picture taken with the 75mm contains more information (texture etc.) than a 100% crop of the same picture taken with the 45-150 at 150mm.

Conclusion: the 75mm is sometimes criticized as a lens lacking flexibility but these tests prove that it can readily replace a good quality consumer telezoom from 75 to 150mm at least (between 45 and 75mm, I will use crops from the 12-40 )

Conclusion (bis): I am putting my 45-150 on eBay tomorrow