Pentax-A 28-80 3.5-4.5 macro.

I have just been given one of these lenses but have a slight problem. It looked like it had a badly scratched filter on it, but when I unscrewed the filter (in fact it popped out, it's held in place by 2 metal rings) I found out it was not a filter at all but appears to be the front element, about 3mm thick, behind whgich is another, much thicker, element that seems to be held in place by the front element. The thicker second element is fine, but the front one is badly scratched. Does anyone know where I can get a replacement front element? Also, is this lens any good? It seems to get mixed reviews.
I was also given an Auto-Chinon 28m f2.8 lens, in very good condition, which I have never heard of. Any info much appreciated!

It's just not cost effective really. You can buy a new lens for such a low price that repairs are a doubtful proposition.

Thanks John, just seen someone sold one on here for £12, so I will bin the 28-80. May as well play with the Chinon lens though, but can't really think why I need it. I turned down a free Clubman 70-150 macro, can't find any trace of them on the net, has anyone ever heard of it?
Still searching for a cheap macro lens.......

Buy a cheap prime and a reversing ring? It works very well...

K.

I'll second that. Or a cheap set of manual tubes.

A.

I have got an Auto-Chinon 28mm f2.8, but the aperture ring does not change the aperture when mounted on the camera. Takes nice pics at f2.8 but would like to be able to use it at all apertures. What am I doinfg wrong? Would this work for macro with a set of tubes?

I've got a Pentax-A with scuffed front element too. I can't really be bothered to replace it with a good example as by most accounts it's not a particularly good lens. I just fancied the challenge of fixing it as the price was low. If I ever see a horribly fungus-infested one with unscratched optics I'll probably buy it and build one good lens from two.

What mode are you using with the 28mm? If you're in Av then the aperture ring won't do anything - the camera will meter and shoot with the lens held wide open regardless of what you do. Switch to M mode and it'll work, although you'll need to master stop-down metering and deal with the fact that it has a rather whimsical view of the correct shutter speed with apertures smaller than f8...

Ah ok got it now, the metering seems fine at all apertures, very peculiar that the foregroungd and background move in relation to each other at different apertures though... never seen anything like it. Also can't seem to get any dof preview....
I have binned the 28-80, its too scratched to be any use. Though kept the second element, have to think of some use for it.