On a budget: fast Vintage Wide-Angle lenses for your M43?

First: Remember the crop-factor. They legacy wides will behave more like a "normal" in mFT-system, not like wide angle lenses. So, with a 28mm lens you'll get a FOV of 56mm lens (about). Cropping to the center, you know. In this system the "normals" are around 25mm.

F-stops remain the same. F2.8 is F2.8. But the DOF will also be the same you'll get from a 28mm lens at F2.8  - or with a 56mm lens at F5.6.

T-stops ( transmission) is bit harder - it will depend on lens costruction and design, quality of the glass, coatings etc, so it varies between the manufactures and lenses more. But it is always less than the F-stop, even with modern lenses. Thumb rule: F2.8 is lets light in for T3 or less. About the same with new ones, too, so you won't lose there...

So, for a wide angle lens you need to search for something wider than 20mm - and they can be quite rare, and usually not too fast.

I have some old Zuikos, (21mm, 28, 35, 40 etc), old Edixa Westromat 35mm M42, Konica Hexanons, have used some old Canon FD-lenses... All behave differently. Common rule: full open, the faster the lens is, the softer (or dreamier) it is. Good or bad - depends what you are searching for.  Sharpest of the bunch are the Hexanon 40mm f1.8, and Zuiko bellows macro 80mm, image style quite "modern". But sharpness is not everything, and sometimes overrated. I like the dreaminess of the Zuiko 28mm f2 wide open...

All above lenses became sharp enough for usual shooting at F5.6 -F8.

For a sharp and "easy" lens take a look at Sigmas 19mm and 30mm F2.8 lenses. AF, EXIF etc work, For wider ones the zooms starting from 12 or 14 mm are good or exellent choises - some better than others. The old FT version Zuiko D 12-60mm f2.8-4 is still one of the best all rounders, and can be found for reasonable prices used. It needs the FT-mFT adapter, and focusing can be slowish in other than EM1-bodies, but it works optically very well even wide open, EXIF works and so the IS system is easy etc.

I hope this helps.

Cheers!

Jouko
'The best camera in the world is the one you have with you when you need it'
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