The Pergear 50mm f1.8 does pretty well on the technical side of things, pretty good sharpness across all around but there is some slight field curvature, so focus across the board is not perfectly even. For example, you’ll notice that the corners are sharper than the edges. That’s pretty common with third-party lenses.
Also, keep in mind these charts were shot with the X-T2. RAW files from the X-T3 and X-T4 are output with some extra sharpness backed in.
Sharpness is very good in the center, however, there is this strange thing happening where there is almost this haze that creeps into the center starting around f5.6. I’m not sure what that is or why that’s happening. My lighting situation was very controlled here, two 800W softboxes on each side of the test chart.
You can see that the white kind of blooms out a little bit.
In general, this lens does struggle a little with contrast and clarity in bright situations because of that blooming.
There is some slight hazing with these high contrast charts but the lens is still very sharp.
Corner sharpness is very good.
Midframe sharpness is decent but it improves by f4. You’ll want to be at about f4 or f5.6 for the best results.
There is a donut of mild softness that starts around mid-frame and extends out to the edges. By the corners, it gets sharp again.
Edge sharpness is ok although does struggle with the high contrast a little. You’ll want to be at about f4 or f5.6 for the best results.
There is a little bit of vignetting when shooting wide open. No big deal really.
Safe to say there is no distortion, or at least very little distortion. The red are straight lines created in Photoshop that line up against my less than perfect white tape lines from my old salvaged chart that I pulled out of storage.
In extreme conditions, you’ll get some fringing with some really high contrast. Like water droplets reflecting sunlight. Nothing really unusual for this type of lens. Clicking the little “remove chromatic aberrations” button in Lightroom does not fix this. You’ll have to manually remove them.
Longitudinal Chromatic Aberration
This lens will see a very slight longitudinal Chromatic Aberration. It’s subtle but occasionally you’ll see it fringe the edges of high contrast bokeh.
I don’t see it in most situations.
Sunstars look like this.
Center Frame Ghosting At Higher Apertures
The Center frame ghosting kind of looks like this. You get this almost orange ghosting in the center of the frame kind of like an Instagram effect. It only does it when you’re at certain angles from light sources and when stopped down. It starts to show up at around at f4. Opening up to about f2.8 to f2 clears it up. Very strange.