FA 28 - 70

Hello all,


A local camera shop has a used pentax FA 1.4 28 - 70 AL. Has anybody used this lens, if so what do you think of it with a k20d?

What does the AL designation mean?
Is £80 a decent price?

Dave

can not find a f1.4 version only f2.8 and f4

1.4 = 1:4 ???

Aaaah perhaps I read the label wrongly. it is probably the f4 version.

Can't tell my 1 from my f

It seemed pretty well regarded, I'd think £80 a bit steep but that's just me. Check for separation of the rear elements as I remember reading that these lenses can suffer from that.

Doug please could you explain the difference between 1.4 and 1:4. I think my brain has gone walkabout..

I really need to look in shop windows more carefully....

the wee plasticky one? It's very light, very usable, and I have one here that I haven't used in months. It's no way worth £80, closer to £50. They have a rep of the rear elements coming apart. My copy's fine and even has a hood.

If you're interested, drop me a PM.

Example shots:








Bret

I think (he says tentatively).

the f4 is the same as 1:4 so the ratio of the objective lens to the aperture is 1 to 4. wide(ish).

f1.4 the ratio is 1 to 1.4 or 1:1.4, quite wide. You can see lots of light as you look through.

There are some belting lenses with 1:4 (f4) max apertures.

I look at http://www.pentaxforums.com/lensreviews/category-SMC-Pentax-FA-Zoom-Lenses.html for a start.

I have owned 2 copies of this lens, which I have used as walkabout lenses on my MZ6. Apart from the rear element separation mentioned in an earlier post, they can also develop a 'rough' zoom action.

Optically the lens is pretty good, there is some distortion at the 28mm end , but not too bad. In the film days it was considered a mid range lens, a step up from the 28-80 and 35-80's that were sold in kits with many of the MZ series of cameras.

On my K10, the lens tends to be quite slow focussing, but I definitely find it superior to the MK1 18-55 above 35mm.

As for price I purchased my current copy as new old stock for £20 about 18 months ago. £50-60 seems to be the current price on ebay plus postage, so £80 is not so far away.

Regards - Steve

Got one of these and quite like it - nice range for walkabout. Mine has a rough zoom but doesn't impede shooting. Excellent lense for the money.

I was using mine today for a commercial shoot for a national magazine.

AL means it has an aspherical element

Thanks for all the information and explanations. I quite like the idea of a light walkabout zoom.

A couple of questions:

1.How do you look out for 'rear element separation', does it just not focus?

2. Frogfish what do you mean by 'rough zoom'?

Dave

A matt/frosted look looking from the back - usually not over the whole element. Easier to see slightly obliquely but pretty obvious. Sadly it's not the very last element which is pretty easy to get out (not that I have much clue how to re-cement them anyway)
Neal