[peterh337]

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Example

Some of them are not Pentax.
Most of them are not full-frame, but AFAIK the recent APS-C models will still work, automatically telling the camera to create a smaller (15 megapixel) image.

I am looking for a lens for the very occassional distant shot from a light aircraft.

I have a 70-200 Pentax from several years ago; APS-C, used on the K200, and that may actually be pretty good. It was cheap; something like £200 new.

[Lowell Goudge]

Xa quick scan shows most are A70-200/4 manual focus lenses, the was one FA70-200/4-5.6 AF lens,

All of these are full frame lenses, but not really worth much.

The FA will be better for Chromeric abberation but slower by a stop at the long end.

If you want a really good lens look for a sigma APO 70-200/2.8 EX with no DG designation. Last of the sigma film era fast 70-200 AF zooms but until the latest offering by far the sharpest

Many of the DG designated lenses, specifically those that offered "macro" were soft especially at the long end

[RobA_Oz]

All of those examples are designed to cover the full 35mm frame. Some are auto-focus and many are auto-aperture. The 70-200mm zoom range was, and still is, a standard for focal lengths for 35mm SLRs. The Pentax DA*50-135/2.8 on APS-C covers the same range of angles of view as the 70-200 zooms do on 35mm film or sensors.

[peterh337]

OK I need a bit of help here...

I don't need f2.8. I already have the outstanding 24-70 f2.8 and that is enough ballast to keep the backpack sitting firmly the right way up

A 70-200 f2.8 is one heavy lens.

Can anyone recommend a 70-200 (or similar range) f4 or so, which would work fully automatically with the K1? I usually shoot in TAV mode - f8 for best sharpness with most lenses, and high shutter speed because it is handheld. The K1 has very good stabilisation but it needs to know what lens is attached, which rules out old lenses unless you configure it manually which I don't want to do.

You may laugh at this but for years I used a 500mm f8 mirror lens. Very light, very compact, but the quality was poor, across several I had, one of which was a pricey Tamron (£500 in the 1980s). I now have a £100 Vivitar one... I don't understand why the quality of these is as bad as it seems to be.

[BigMackCam]

As has already been stated, those are all full-frame lenses. Typically, variable aperture 70-200 lenses aren't badly priced, but they're also quite limited. Older variable aperture zoom lenses (and newer low cost equivalents) tend to be quite soft at the long end unless stopped down considerably. Typically, you'll need to stop them down to f/8 for decent performance, and they usually peak around f/11. So, you need a *lot* of light to use them effectively. Compare that to a modern 70-200 f/2.8, which will perform quite well even wide open, and produce excellent results from f/4 or f/5.6...

[BigMackCam]

Can anyone recommend a 70-200 (or similar range) f4 or so, which would work fully automatically with the K1? I usually shoot in TAV mode - f8 for best sharpness with most lenses, and high shutter speed because it is handheld. The K1 has very good stabilisation but it needs to know what lens is attached, which rules out old lenses unless you configure it manually which I don't want to do..

I don't know of any 70-200 f/4 for Pentax. That said, if you're shooting mostly at f/8, then a fixed maximum aperture of f/4 isn't strictly necessary or beneficial to you... in which case, you might consider something like the Tamron 70-300mm f4-5.6 Di. It's a full frame lens with a very good focal length range and, stopped down to f/8, will give you good results - not in the same league as a modern 70-200 f/2.8, but very decent. You can pick up a brand new copy for about £115...

[clackers]

OK I need a bit of help here...

I don't need f2.8. I already have the outstanding 24-70 f2.8 and that is enough ballast to keep the backpack sitting firmly the right way up

A 70-200 f2.8 is one heavy lens.

Can anyone recommend a 70-200 (or similar range) f4 or so, which would work fully automatically with the K1? I usually shoot in TAV mode - f8 for best sharpness with most lenses, and high shutter speed because it is handheld. The K1 has very good stabilisation but it needs to know what lens is attached, which rules out old lenses unless you configure it manually which I don't want to do.

You may laugh at this but for years I used a 500mm f8 mirror lens. Very light, very compact, but the quality was poor, across several I had, one of which was a pricey Tamron (£500 in the 1980s). I now have a £100 Vivitar one... I don't understand why the quality of these is as bad as it seems to be.

Legacy zooms and wide angle primes are weak compared to today's products, Peter. I mean, that's across the industry, not a particular brand.

But if you must, you could try something like the F 70-210 f4-5.6. Has just a 49mm filter size. The Sigma 70-300 DG f4-5.6 is newer.

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Last edited by clackers; 11-08-2016 at 05:41 AM.

[D1N0]

There is one FA 100-300 zoom that is pretty well reviewed:
SMC Pentax-FA 100-300mm F4.7-5.8 Reviews - FA Zoom Lenses - Pentax Lens Reviews & Lens Database

[lemonsoda]

Take this one:

Sigma AF 70-300 mm DG OS ( Bildstabilisator ) für PENTAX Neuware 85126572617 | eBay

- it's new
- it's pretty good (for the price)
- it's cheap
- it's reasonable small and light

[cyberjunkie]

Legacy zooms and wide angle primes are weak compared to today's products, Peter. I mean, that's across the industry, not a particular brand.

But if you must, you could try something like the F 70-210 f4-5.6. Has just a 49mm filter size. The Sigma 70-300 DG f4-5.6 is newer.

I don't fully concur with your statement.
I would reword it as:
"the best, very expensive zooms of today (fast, same max aperture across focal range) are sharper and give more contrast than film-era zooms. Especially wide open"
Though the best vintage zooms, if used at their sweet spot and with some post-processing, can still offer an incredible price/value ratio and take very sharp pictures.
I agree with your choice of the Pentax-F 70210mm. Pretty good.
For a wider focal range i'd go for the Sigma Apo Macro 70-300mm last version. Pretty decent, AFAIK. I have the older version, which seems a little worse.
For shorter focals, i'd go for the Pentax-F 35-70mm, the Pentax-FA 28-70mm f4 AL, and the Pentax-FA 24-90mm.
From very cheap to not expensive.
If manual focusing is not a problem, the two Pentax-A 35-105mm f3,5 and 70-210mm f4 can still be found for almost nothing, and should perform well on the K-1 (if stopped down a little).
Pentax film-era AF zooms look plasticky and a bit wobbly, but they are very well made. More the series F than the FA, i'd say.
Very likely "screwdriver" in-camera AF motors of the time didn't have enough torque, so the lenses had to be made that way.
I can't say that i'm impressed by the build quality of recent high cost Sigma zooms.
The old EX DF version of the 28-70mm f2,8 sometimes gets stuck at minimum focusing distance, and i have to free it manually.
The 24-70 EX DG f2,8 has been a nightmare. May bad, probably. I purchased it on Ebay, like new, no bumps no signs of use. Tried it quickly at home with the K-5 II: everything seemed ok and i released positive feedback. Since then has been kept dormant, waiting for the K-1 (i had better options for APS-C sensors). By mistake i sent it to the official repair service of Sigma Italy, together with a 120-400 that has to be upgraded for free for the new K-1, and a 30mm DC with damaged front glass. Yesterday i've been contacted by email: the focusing helicoid has a problem close to infinity and the zoom guide is bent. 200 euros for parts/assembly/checking/fine tuning. The lens showed no damage whatsoever. Like new! Probably it just took a bump on the front, on a kind of surface that left no traces.
Some of my Pentax zooms took a few hard knocks, but all of them still work as new.
Even the Sigma zooms that give no problems, like the 10-20mm DC or the 120-400, give me a distinct feeling of quite feeble innards.
A little better feeling with my primes, like the three macros... which are VERY good optically.

cheers

Paolo

[peterh337]

Would this one work with the K1, with auto focus, and the various camera modes?

[UncleVanya]

da* 60-250 can be modified to work on k-1.

[BigMackCam]

Would this one work with the K1, with auto focus, and the various camera modes?

Yes, Peter - that's the one I suggested in my earlier post A Tamron lens with the "Di" designation is for full frame or APS-C; "Di II" means it's suitable for APS-C only.

Don't pay that price for it, though... Jessops are doing it for £123 right now, and I've seen it drop as low as £100 from time to time...

[lpfonseca]

Would this one work with the K1, with auto focus, and the various camera modes?

Yes, the Tamron AF 70-300 Di will work with a Pentax K-1. It works fine with my K-5 and my Z-1p.

[peterh337]

The Jessops one is a Canon mount, however. I found it on Amazon for £125

Thank you all.

The main use will be landscape (from aircraft) in good light, usually sunlight. I can use F8 no problem. The K1 doesn't make any real noise until you get to ISO 2000 or so.