Considering a 28-200

I'm considering an AF 28-200, and wondering about the respective merits of Tamron and Pentax.

The ones I'm considering are:

Pentax FA 28-200mm f3.8-5.6 AL (IF)

and

Tamron AF 28-200 f3.8-5.6 LD Aspherical (IF) (PKA fit).

I'd appreciate any comments on either - and also could someone let me know if IF means that the front element doesn't move when you focus (and zoom, preferably, obviously).

if=internal focus..you are right.
I have the pentax 28-200 and it's fabulous.
It is a great match to my ds2.
if you were a velvia shooter usinge primes you'd notice the limits of the lens as far as sharpness is concerned, but you'd not be able to tell it from a prime using 400 speed film.

They are virtually the same lens, with the exception that the Pentax has 'SMC' ......

My Dad has one of the Pentax versions - I'll be blunt, I don't like it much but for a 1 lens solution it's OK.

Whilst the lens is quite compact to start with, when zooming the lens almost doubles in length...

Will

The Pentax version is a very useful 'walkabout' lens. It has its critics, but I love it. I used mine very effectively to take some aerial shots of my local area. Having the effective range of 42 - 300mm (approx) made it an ideal lens to use on that, and many other occasions.

If I have to take one body + one lens out for the day, the SMCP-FA 28-200mm AL (IF) is the lens I use.

Chris, I sent you a PM. I have a spare one of these lenses.

Quite so. I have a Sigma MF 28-200 (PKA) that I've had for many years and it's been extremely useful on walkabouts as you say, including a trip along Striding Edge in the Lake District.

Quite fancy an AF one, hopefully with (even) better optics.

Thanks - I've sent you a reply.

Could you elaborate a bit on why you don't like it, Will? Presumably it's not just the length..

I found it a bit unwieldy, the zoom effect unbalances it a bit. I also don’t like the feel of the lens, very plasticy but then I feel the same way about how all of the Pentax zooms (28-80/28-90) from that era feel like construction wise.

I've never done any specific testing but back in those days when I still went shooting with my Dad I always preferred my results over his. My slides always seemed to jump out that bit better...

For a lens having 7+ X zoom ratio, I'd say that for it to only double in length when zoomed between it's extremes, was actually pretty darned good. Measured from the front surface of the filter thread to the body contact surface it actually extends from 85mm long @ 28mm FL to 135mm long @ 200mm FL.

On a film body, this single lens covers most of the commonly used focal lengths from wide angle to medium telephoto and it suffers, IMHO, from some very minor compromises at the long end. It's a great lens to have in your arsenal for the occasions when only one lens can go on the trip. It's light enough at only 501gr to carry around all day too.

As a postscript to this, following the wise words from the contributors to this thread, I've acquired an example of the Pentax SMC FA F3.8-5.6 28-200 (IF). So far I'm very pleased with it, but have noticed one interesting thing.

If I zoom it all the way to 200mm, and focus on an object some distance away, the object remains in focus if I gradually zoom it out towards the short end.

This was expected behaviour, and corresponds to all the other zoom lenses I've had over the years, although the precision with which focus is maintained on zooming can be a bit variable.

However, this was not true if I focused on something very close first. What happened was that if I zoomed to 200mm, and focused at the closest focusing distance of about 18 inches, and then zoomed out, the subject went dramatically out of focus until it got to about 50mm, at which point it came back into focus again.

Focused on something a bit further away, the effect was less pronounced, until at about 6 feet away and further, it was not noticeable.

It's not at all difficult to refocus when it blurs on zooming, but it does seems strange.

Could someone that has one of these (Mannesty?) please see if theirs behaves similarly?

Thanks very much.

I have the Tamron virtually permanantly on the istD and it suits me perfectly.
The only gripe is that the zoom is a trifle loose and you need to ALWAYS have the zoom lock on when not in use - but then it might just be my particular lens.

It's not just your lens Graham - I have the Tamron 18-200 and also need the zoom lock on when not in use.

Lovely lens though and almost permanently attached.