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Got me a new zoom lens - for a fiver!

karma mechanic
Posted 03/06/2011 - 17:28 Link
A long time ago I'd obtained the 50-200mm kit lens, but I'd never really used it since the images were never particularly sharp. By f/8 it was improved, but that precluded using it for shots with restricted depth of field. I'd carefully adjusted the AF, but it was never worth using at f/5.6. I suspect that my copy is particularly poor.

The other day I picked up a 70-210mm f/4.5 Sun zoom in PK mount from a market stall for a fiver. That was the asking price - I didn't try to haggle

The first thing to do was to compare it to the 50-200mm... bearing in mind it is the long end I'm interested in.

Some test shots quickly revealed that at f/4.5 the Sun zoom is considerably sharper than my kit 50-200mm is at f/5.6, and the kit lens needs f/8 before it is able to compete with the Sun at f/4.5. The Sun at f/5.6 and f/8 is better still, but sharpness falls off a little at f/11.
The Sun is sharp across the field, while the kit lens tends to be poor at the edges. The comparisons were done on a heavy tripod with focussing using 10x Live View and 2 sec timer.

The Sun zoom is quite heavy, prone to some purple fringing, needs stop-down metering if not wide open and obviously manual focus, but the focussing is very snappy and easy. I've been using it wide-open on the AV setting.

Here's one I took earlier at f/4.5, 210mm, 1/200th at ISO 100:
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and here's a 100% crop - the heat shimmer has distorted the details but in spite of that the sharpness seems ok:

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I'd call that a bargain!
My own website is www.richardgaddphotography.com

Also on 500px
snappychappy
Posted 03/06/2011 - 17:32 Link
Very nice images, a true bargain.
Epithet Man
Posted 03/06/2011 - 21:33 Link
Wow. The traffic stopped for you to take the shot
Dangermouse
Posted 03/06/2011 - 23:38 Link
It's not much of an advert for the 50-200mm is it?

I've got an old Pentax-F 80-200mm which I paid a tenner for with a bit of mould, cleaned that out very easily (was only the inside of the front element) and reset the infinity position, it's now a decent performer. I've used it for shots from moving vehicles before now (staving off boredom as a passenger on motorway) and it coped astonishingly well.
Matt

Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
Posted 04/06/2011 - 07:15 Link
Epithet Man wrote:
Wow. The traffic stopped for you to take the shot

Must have been the M25
A poor life this, if full of care,

We have no time to stand and stare. W.H Davies

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