How about sharing a few with us ?

I'm surprise Mike handed it over, it is very sharp & contrasty. Great colours too.

I'm expecting a raft of fishy comp entries from you now Mhuni... enjoy !

Nathan, I agree entirely & you've got shots here you wouldn't have got at F4. I may be a little harsh on shot 1 as it could be high iso leading to loss of detail/sharpness, but #2 is is really very soft indeed & hardly proof of an "incredible" lens. I think you may be a little over-excited at your latest aqcuisition, it happens to us all.

Please come back in the cold light of day & blow my socks off ! Don't try & bend the laws of physics, use the technique we know you have, & produce some stellar shots.

Of course, if you did notice a difference, I'd say keep the best one. I'd rather have a lens that gives excellent results, even if used only a few times a year, than a lens I use everyday that gives poor results ! But I'm inclined to think that both the 1.4 & 1.7 would give superb results.

Of course the 1.7 has a flatter field so is more usefull with tubes etc. but you sure don't need macro advice Mike !

Mike, if you don't use them much & you don't see the difference, then sell the one that will fetch the most money which you can put toward a bit of kit you would utilise more.

IMHO of course.

It seems as F2.8 isn't quite fast enough, even with SR the first 2 are suffering from camera shake, number 2 really quite badly.

What I'm getting at is that a fisheye bends straight lines in order to get such a wide view into the frame. By using a fisheye intended for full frame on a crop camera you end up with the middle portion of the image, which has the downfall of curved lines, but without the benefit of a 180 view as you are essentially missing the edges of the frame.
It doesn't have to be a negative, but you say you dislike the effect & that you want it for landscape/architecture which traditionally requires as accurate a view as possible.

Your best bet for samples would be to head over to flickr and search for "k20d zenitar" or indeed the word zenitar & any pentax/samsung dslr or nikon aps-c model (canon & olympus are slightly different view) - check the tags of any image you view just to confirm it is using the zenitar & correct camera model. Then see if you can live with the distortion.

I actually had a Zenitar 16mm delivered today, but haven't had chance to use it in anger yet. Seems to give decent IQ from the limited test I've given it but I would imagine the Pentax 16-45 would give far, far better results at any aperture. If I was still shooting on a crop camera I would not have entertained picking up the Zenitar.

I wouldn't go for a full-frame fisheye on a crop camera as you'll get a rectilinear look with some barrel distortion.
If I were you, I'd keep saving til you can afford something like the 16-45mm or a 3rd party super wide (10-20, 10-24 etc) and in the meantime look into a free image stitching program for the times when you need to go wider.

What about a Sigma 180mm f3.5 macro ? You'd have a cracking macro lense for bugs then too.

I guess you'd need to check it has a focus limit switch to stop it hunting too much if you intend on using it for concert work.

They're not all HDR Stefan, but the majority are.