Aside from the difference in focal length, is there a big difference in picture quality between the Zuiko 21/24/28 3.5 lenses? If the focal length is not a concern, is the price difference between these lenses worth any upgrade in quality?
I have only used the MC 24 2.8 and the 28 3.5. The MC 24 2.8 is better overall in my opinion, particularly with regard to color and contrast. The 28 3.5 does really well when it comes to sharpness into the corners.
I have a 28 f/2.8 and its quite nice. I like the natural light fall off on my FF sensor... but I'm currently looking to go wider. I probably should have gone with the 24 f/2.8, that is a steller lens.
I also have the OL 28/2.8 (very recent purchase) and plan on testing it against the Canon EF 24/2.8 that I have had and enjoyed for years. Now that I have a better viewing screen on my 5D the OL lens is looking better...