F24-50 f4 and FA100-300 f4.5/5.6

Reports I've read suggest that these lenses are mediocre at best in terms of performance - I sometimes think we expect too much from zooms!

Does anyone have personal experience of either of these lenses?
If so, I'd appreciate comments good or bad with a view to possible purchases.

Thanks
Kimbo.

Hi Kimbo

I have just purchased the 24-50mm Pentax-F zoom... you writing 'mediocre at best' certainly hasn't got my hopes up . So my plan is to compare it against a few different Pentax 50mm lenses (K, M and A), sadly i am not lucky enough to have a Pentax 24mm lens to compare it against at the wide end .

Can anyone tell me a good way to test these lenses? I would like to use the *istD but obviously the 24mm end becomes about 36mm and so on, and then (I presume) it won't give an accurate idea of edge sharpness and edge distortion but would at least show contrast and overall picture sharpness differences. I would shoot RAW images.

What is the best subject to shoot to show the differences to their fullest, i.e. a chequerboard pattern on a vertical surface with some colour thrown in? Any advice from the group would be appreciated.

Thanks
Simon

Hi Simon,

I look forward to hearing your comments after you've had a chance to give the lens a good workout.
Personally, I would try a range of normal everyday type shots with varying lighting conditions and focal lengths. I don't rely too much on test results by photo mags and the like as it is the opinion of real photographers in the real world that really counts.
Technical testing is a great way to know which lens is best but where the differences are not really discernable to the naked eye, then factors such as handling characteristics and price become more important.

A simple test that I like to perform is to tripod mount the camera above a newspaper page and look for edge to edge definition.

A 24-50F lens recently sold in the states (ebay) for almost $200 and one here in the UK for around £50 - would that be yours Simon?
If so, then I think you've bagged yourself a real bargain even if it's not one of Pentax's best!

Thanks for the advice Kimbo. I will give the lens a good workout and let you know.

As for the lens recently sold on Ebay for £50... that was me ! And I thought it was a bargain too. I half expected that as it only reached £50 that people knew more about the performance of this lens than I did (which was almost nothing) and that it might turn out to be a 'dog' but now I have an inkling that it wont be so bad.

Cheers
Simon

For what it's worth...
The SMC-F lenses are lovely, IMHO. I've just bagged two more from eBay - the 35-70 and the 70-210. First impressions are very, very good on the *ist-D. Image contrast and detail is great! And such small lenses too!
They go well with the 28, 50/1.7, and 100/2.8 SMC-F that I already have.
I'll be giving them a more thorough work out later, but that's the thing that's really brilliant about the Pentax system - you can use 13 year old lenses on new kit Plus there aren't so many users out there, so bargains are to be had!
(Can't do that with Canon )

Matt

Hi,

I have used the M, A and F versions of the 24-50 lens. The F version has become the "normal" lens on my MZ-s. I haven't noticed a real difference in the optical performance between the 3. Despite this the early versions tend to have good reviews but the F doesn't. I think is is fine optically and that many these days are more used the wider ranges such as 24-80 and more. The real advantage in my book is that it is fixed aperture which makes life so much easier with manual metering and slide film.

Regards
Kim