I too want a high-quality fast normal lens for APS-C. Since I cannot actually try any lenses before I buy them I am forced to evaluate based on what other people say and shoot.
The FA31/1.8 is available and no-one ever complains about the quality. However, it measures closer to 32mm and so is too narrow to be normal. I don't like 35mm or thereabouts on cropped sensor; it just feels wrong. Perfect normal is 28mm, a focal length missing from the current Pentax line-up, for some reason that cannot be explained, especially as it was one of the most popular focal lengths in the film era.
The second problem with the FA31 is that it now sells for £1140.
The Sigma 28/1.8 is the "correct focal length" and
much cheaper at £330. The problem is -- don't hate me here -- that it is a Sigma, with all the problems that entails.
Originally posted by WMBP except that mine has a small problem where it sometimes won't talk to the camera.
Yeah, exactly. Buying a Sigma is a gamble. I've read any number of reviews complaining about random focusing problems. It's fairly soft anywhere outside the center (unless you stop down a lot). I actively dislike the feel of Sigmas in my hand. This lens is big and weighs a ton. And I'm not so hip to their rendering. But the price is right at £800 less than a lens with that special Limited quality.
What about other systems? I know Canon has the
28/1.8 USM at £390. It's reputed to be soft wide open and doesn't have the godlike bokeh of the FA31, but it does have USM. The
24/1.4 L II is difficult to compare since it's in a different class entirely: big, weather-sealed, USM, wider. And it's more expensive than the FA31 at £1350.
I would love a Pentax 28/1.4 Limited, even if restricted to cropped sensor. But if it existed, I doubt I could afford it.
Just to be clear, I don't mind stopping down once to sharpen up the image and twice to get it perfect, but I do not want a lens useful only in the centre. That might be fine at portrait lengths but 28mm is useful for street, landscape and other applications where the sharpness in the corners matters.
All of this brings me full circle to the thread
Vivitar 28mm As FA31mm Replacement? I am happy to have found solid metal lenses that perform well and have a great feeling in the hands, covering full frame, not gigantic, for less than £100. All you give up is auto-focus to get a close focus 28/2 that is well usable at f/2.8 and great at f/4.
It's a perfect street lens and would go well on a new small Pentax Limited body. But that's another story.