[normhead]

The argument against the Tamron has never benen it's IQ. It was judged by one independent site to be equivalent tp Canon and Nikon 70-200s, (I doubt any of them stack up all that well against the pentax DFA) which wasn't out when the test was done. Sigma declined to provide a lens to the testers, which says everything you need to know about their confidence in their version.)

The issue has always been it's build quality, which was the only place it was judged inferior and which dragged it's composite score down below the others. I see it as great addition to the collection of someone who doesn't beat the crap out of their gear the way I do.

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Last edited by normhead; 10-24-2018 at 05:27 AM.

[UncleVanya]

Old but relevant:
Tamron 70-200 F2.8 vs Sigma 70-200 F2.8 EX DG HSM II - Battle of the older telephotos - PentaxForums.com

[jddwoods]

Pretty good. And Norm is right about the F 70-210. No 2.8 and variable aperture but very good image quality. These are both so inexpensive you could get both and probably decide to keep both. Of course my "pretty good" could be your "terrible".

I have always liked the F series lenses. Periodically I stop into goodwill shops and fundraiser flea markets to see if I can find any. They are usually found attached to an older film body such as an SF10 (which I had) SF1 of P3 which were the Pentax bodies of that vintage that somebody has given up. For some reason used F series seem to be hard to find. I check B&H and KEH periodically but do not see to many coming up used. I made the mistake of selling my F 35-70 compact zoom but fortunately kept the F 28mm f2.8 which I use quite frequently.

[bassek]

Another lens I haven't seen mentioned is the F 70-210. Maybe not as good as a 55-300 PLM but we got ours for around $60 with and SF1 film body thrown in.

Another vote for this lens if you are on a tight budget. It's heavy (any f2.8 is heavier) but has fast AF.

Seb

[jgnfld]

On the speed issue, I have been migrating a bit towards slower lenses since I got my K70 to replace a K50. The new camera has taught me that I can go (into what to me have previously seemed) much higher ISOs with 3 or even low 4 digit values with little or no IQ loss. I live in Newfoundland which commonly has dark shooting conditions given fog, rain, low sun angle in winter, etc. but like you concentrate on landscape and wildlife as one might expect given the environment here. The environment also pretty much requires WR lenses. I would MUCH rather pack a lighter lens for a hike back somewhere than a heavier one.

This, for example, was taken from a moving sailboat with a 55-300 PLM WR on a K70 at:
Focal Length 260.0mm
Exposure Time 1/3200s (0.0003)
Aperture F/7.1
ISO Equivalent 320


(The IQ at full res is much better than the down sampled version here.)

So I guess I might ask why exactly do you want f2.8 when you have a K3 with its sensor which is nearly as good as a K70s sensor at low light? Is the weight and hassle of the faster lens really what you need? While I have lots [ too many??? ] lenses including a number f2.8 or faster, I have found myself gravitating to the 16-85/55-300 PLM pair as my most used lenses when going outdoor when I have no particular, specialized subject in mind. Neither is particularly fast, but that really isn't an issue give their overall performance with a good sensor. And if I do want to stop action, both are quite capable (when paired with a good sensor which your K3 has).

Sorry to add a complication.

[cyberjunkie]

I also considering the Tokina 80-200 MF...

I have one.
Great build, as all other AT-X/AT-X Pro lenses.
It has zoom creep though.
Good stopped down, not so good wide open. Not surprising, most fast film era zooms are the same.

From my personal experience I'd favor the Tamron, if you really want a bulky f/2.8 AF zoom.
Optical quality is very good for the price.
The only problem I have is that it front focuses on my K-1. A correction of 10 is not enough to make it right at the long end.
Worked great on the K-5 II.
I should have it fixed.

IF you are okey with a slower zoom, the best vintage tele zooms made by Pentax are the Pentax-A 70-210mm and the Pentax-F 70-210mm.
The latter has screwdrive AF and is not much more expensive than the A version.
If you are fine with the way F lenses look/work, it's a good choice.
For some reason a certain number of them have fungus or lens separation. Finding a good example should be quite easy, just check the state of the optic.

The old Pentax-FA f/2.8 is not worth its (high) price IMHO... unless you are a die-hard pentaxophile collector.
The Sigma is not cheap either, but it's reportedly very good and the HSM version has fast AF. Never tried it but my HSM lenses focus fast and precise on my K-1.

If f/3.5 on the whole zoom range is enough, let's not forget one of the best MF zooms ever: the Tamron SP 70-210mm model 19AH.
It has a great macro (the Pentax-A does not) and has very good image quality at close range. With the PK/A Adaptall-2 ring it practically works as a Pentax-A lens... you got to focus manually

Considering everything, I'd either go for the Tamron or the Pentax-F. Unless you are already very comfortable with manual focusing.
If not, I'd suggest to start with an MF prime that could be purchased with some of the money you'd save going for one of the least expensive AF options.

[mattb123]

I had a 60-250 before and it eventually died (AF). It was a nice lens and with a minor mod was good on the K-1 as well.
I replaced it with the Tamron 70-200/2.8 and I really like the rendering but I wish it was sealed. Mine is already getting some dust in it (understandable for the conditions it has seen).

I'd love to see an updated, sealed, full frame 60-250/4 or similar!

[lotech]

Great photo taken on a dull day very nice ! but sorry to ask, are you sure the exposure detail are correct, I am rusty on the calculation, according to 'Sunny 16 rule' the day was brighter than a prefect sunny day ... my EDC combo was first the kit 18-55 WR with 50-200 WR, then the 16-50 DA* with HD 55-300 WR, both tele are very sharp but bit slow and noisy to focus, the PLM would be too dark for me as I shoot quite a lot of low night under Tungsten lighting beside overcast and rainy day, I want a faster lens since my 55-300 got stuck in focusing after rough use for years, the weather sealing probably worn out.

Sunny 16 rule - Wikipedia

Exposure Calculator

On the speed issue, I have been migrating a bit towards slower lenses since I got my K70 to replace a K50. The new camera has taught me that I can go (into what to me have previously seemed) much higher ISOs with 3 or even low 4 digit values with little or no IQ loss. I live in Newfoundland which commonly has dark shooting conditions given fog, rain, low sun angle in winter, etc. but like you concentrate on landscape and wildlife as one might expect given the environment here. The environment also pretty much requires WR lenses. I would MUCH rather pack a lighter lens for a hike back somewhere than a heavier one.

This, for example, was taken from a moving sailboat with a 55-300 PLM WR on a K70 at:
Focal Length 260.0mm
Exposure Time 1/3200s (0.0003)
Aperture F/7.1
ISO Equivalent 320


(The IQ at full res is much better than the down sampled version here.)

So I guess I might ask why exactly do you want f2.8 when you have a K3 with its sensor which is nearly as good as a K70s sensor at low light? Is the weight and hassle of the faster lens really what you need? While I have lots [ too many??? ] lenses including a number f2.8 or faster, I have found myself gravitating to the 16-85/55-300 PLM pair as my most used lenses when going outdoor when I have no particular, specialized subject in mind. Neither is particularly fast, but that really isn't an issue give their overall performance with a good sensor. And if I do want to stop action, both are quite capable (when paired with a good sensor which your K3 has).

Sorry to add a complication.

[MossyRocks]

are you sure the exposure detail are correct, I am rusty on the calculation, according to 'Sunny 16 rule' the day was brighter than a prefect sunny day

Given the reflections in the water it seems like was probably shot on a sunny or mostly sunny day as I see blue reflections in the water. Those settings seem like are are only about 1 to 1.5 stops underexposed to the sunny 16 rule. The settings used for aperture and ISO give 4 stops of extra light compared to sunny 16 but the shutter speed eats 5 stops of light compared to sunny 16 so the image would be 1 stop underexposed with those assumptions. With a modern sensor bring things up in post from that wouldn't be difficult especially since it doesn't really look like he ran into any dynamic range limits. Even if it were late afternoon, losing another stop of light, 2 stops under still seems entirely recoverable.

[lotech]

Yes digital has more room for error than film.

Given the reflections in the water it seems like was probably shot on a sunny or mostly sunny day as I see blue reflections in the water. Those settings seem like are are only about 1 to 1.5 stops underexposed to the sunny 16 rule. The settings used for aperture and ISO give 4 stops of extra light compared to sunny 16 but the shutter speed eats 5 stops of light compared to sunny 16 so the image would be 1 stop underexposed with those assumptions. With a modern sensor bring things up in post from that wouldn't be difficult especially since it doesn't really look like he ran into any dynamic range limits. Even if it were late afternoon, losing another stop of light, 2 stops under still seems entirely recoverable.

[UncleVanya]

Yes digital has more room for error than film.

Really? I think the that's a bit misleading. They are DIFFERENT. Film - print film - was very tolerant of overexposure where digital is NOT. Film was less tolerant of underexposure - lost detail was very very lost. If anything film reduced the differences between +/- 1-2 stops, digital is just easier to see the outcome and manipulate the results in real time. Darkroom work was slower, less feedback was given, and it was more expensive to experiment.

[stevebrot]

Yes digital has more room for error than film.

????

Really? I think the that's a bit misleading.

Agreed!

In absolute terms, digital irrecoverably clips both above and below the 14 stop range of higher-end Pentax cameras with limited ability to capture tonal gradation at the lower end of that range.* Color slide film, in general, is famously high contrast with compressed response**; the strategy being to expose to avoid blocked (clipped) highlights with sacrificed shadows. Color negative film is more forgiving, allowing about 13 stops. B&W films are the traditional champions with 15+ stops being available with special development techniques. As noted above, inadequate low-end response with negative film results in little or no detail/tones in the low values. How steep the "cliff" depends on the emulsion being used. With negative films, the strategy is to expose for the shadows and deal with the highlights in the darkroom.

Of course, all of the above pertains to the actual image on the film/sensor and not the usable dynamic range, grain/noise being taken into account. Throw in the variables of digital PP, scanners, enlargers, photo papers, ink-jet papers, and printers and it is anyone's guess what can be accomplished for image for display. There is technique and potential for loss/artifact at each phase.


Steve

* Pentax dSLRs support 14-bit capture in the higher-end models. This translates to 14 EV steps (powers of two), non-negotiable, for the capture.

** Sorry...I don't have actual numbers, stop-wise, though the Web says seven stops.

[normhead]

Color negative film is more forgiving, allowing about 13 stops. B&W films are the traditional champions with 15+ stops being available with special development techniques. As noted above, inadequate low-end response with negative film results in little or no detail/tones in the low values. How steep the "cliff" depends on the emulsion being used. With negative films, the strategy is to expose for the shadows and deal with the highlights in the darkroom.

Do you have a source for these numbers? I've never seen numbers for an every day colour film over 7 stops.
Seven stops, or about 120-1 was the range I was taught in school. And I've read a couple of places that confirm that. I've never seen anyone suggest you can get over 7 stops using most films. Certainly not 13 stops.

13 stops would be a contrast ratio of 8000:1. I've never even heard of 500:1 using film. 512:1 would be 9 stops.