The Minolta W.Rokkor MD 24mm f2.8 has a reputation of being one of the sharpest 24mm lenses ever made. Even Leica licensed it for their R mount, and by that giving it credence as an excellent construction.
So how does it hold up today against modern lenses and digital media?
Since I just got hold of it in a near to mint condition (for a more than reasonable price) and I also own a Sony Zeiss 16-35mm f4 zoom (known for it sharpness at 24mm) I thought a shootout would be a fun idea.
An almost 40 years old $200 prime agains a modern $1200 zoom. How would that end?
Doing the shootout
Dealing with it in a sort of semi-unscientific way I set up my tripod in the kitchen and took pictures of the eastern wall with both lenses at different apertures, all in raw format. I used timer release and silent shutter to remove as much vibration as possible and set the focus at the largest aperture in the center of the image.
The raw images where converted to JPEG in Photoshop without any additional processing, sharpening or lens correction except for a small adjustment for exposure (the same for all images).
Here are all the images. You can click on them to see them in full resolution but crops are included further downing in the post for those of you who are not prepared to jump in at the deep end.
Here follows 100% crops from both lenses for all the apertures I’ve tested with my initial comments and reflections. Feel free to add your additional comments or thoughts in this post’s comments.
There is no doubt, in this shootout the Sony Zeiss beats the Rokkor on every point except one. It’s sharper overall and especially in the off-center and in the corners. It has better contrast, less aberrations and less vignetting. Only in the color rendering I find the Rokker more even and pleasing. The Sony Zeiss tend to be a bit uneven with a warm center and colder corners.
Does this mean that the Rokkor is a bad lens all over? Probably not. First it means that the Sony Zeiss zoom is a very good lens. Second, as long as you stop down the Rokkor to at least f4 or f5.6 you get better to excellent results. From there on it’s almost as sharp as the Sony Zeiss except for the extreme corners.
I also like the colors of the Rokkor better than the Sony Zeiss.
Aberrations and vignetting are worse on the Rokkor but within reasonable limits and if you shooting digital these are easily fixed in post.
One advantage of the Rokkor is also the size and weight compared to the Sony Zeiss. Though not as large as other modern super wide-angle zooms, it’s still a considerable bulkier and heavier lens.
For $1200 you would expect the Sony Zeiss to perform the way it did. For $200 the performance of the Rokkor stopped down to 5.6 or more leaves very little to complain about. A good budget alternativ as long you don’t need those larger apertures or use it’s weaknesses to your advantage.
I did some further investigation into the unexpected low border and corner sharpness of the Rokkor at larger apertures. It seems that at least some of it is due to field curvature at the actual distance I used. Focusing at the corner makes them much more sharp than in my test but then the center becomes unsharp instead. I estimated to just under a meter in difference which is quite much on this short distance.
Normally not really a real world problem since we seldom take pictures of flat walls all the way to the corners. Still it’s always good to know your lenses.
Could be I’ve got a bad sample too.