[Grokh]

Dear colleagues, good afternoon.
I would like to ask such a question - what about the focus speed of the lenses D FA 2.8/70-200 * and D FA 150-450?
Interested in the suitability of these lenses for shooting sailing.
(Now I use the old Sigma 2.8/70-200 and Bigma 50-500 models, but they are almost 20 years old, and their lifetime is tangibly approaching the end.)
The question of applicability with these lenses of the "native" converter 1.4x on the K-3 Mark III camera is also interested.

[UncleVanya]

I'm unfamiliar with photographing sailing - at least in any in depth degree. I have done some sailing and some photography of sailing. I once was present at the start of a leg of an ocean catamaran long distance race. What I recall is that if you are on shore you need a long lens and the action isn't particularly fast with respect to focus speed. What am I lacking in my understanding?

The PLM 55-300 is blisteringly fast focusing. The DA 70-210/4 is not bad at all. I am afraid I have not used either of the lenses you are asking about and my platform is the KP not the K-3iii - I have used the 70-210/4 with the 1.4x and found it to be still speedy. I do not own the 70-210/4 - it was a loaner - so getting any actual metrics would be impossible I'm afraid.

[steephill]

HD Pentax-D FA* 70-200mm F2.8 ED DC AW Review - Focusing | PentaxForums.com Reviews
HD Pentax-D FA 150-450mm F4.5-5.6 Review - Focusing | PentaxForums.com Reviews

[sealight]

Can't speak for the use on a K-3 III, nor the 70-200mm- I've been shooting a lot of drifting cars last winter on my K-1 II + 150-450mm and usually never had the feel I'm lacking anything in focusing speed, so my guess would be both lenses should do fine for sailing (only trouble I had was on a day with particular extreme minus- temperatures...)
about the teleconverter- Pentax recommends to use it on lenses with f4 or faster, I use it here and there with my 150-450mm, here at least for me the results are somewhat of a mixed bag- though generally focus speed doesn't seem to suffer...in total personally I don't like using the TC (both on a K-1 II or a K-3) - but that's maybe because I only have experience using it on my 150-450mm- and as said before, that lens isn't exactly meant to be used with it, think i never tried it in combination with some other lenses I own, other than maybe the 60-250mm f4*...

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Last edited by sealight; 05-28-2022 at 12:12 PM.

[gatorguy]

I have both. With the 150-450 use the focus limiter for fastest performance. Both the 150-450 and 70-200, are quick, concise and accurate. You should be good with either.

[Grokh]

about the teleconverter- Pentax recommends to use it on lenses with f4 or faster, I use it here and there with my 150-450mm, here at least for me the results are somewhat of a mixed bag- though generally focus speed doesn't seem to suffer...in total personally I don't like using the TC (both on a K-1 II or a K-3) - but that's maybe because I only have experience using it on my 150-450mm- and as said before, that lens isn't exactly meant to be used with it, think i never tried it in combination with some other lenses I own, other than maybe the 60-250mm f4*...

Thank you. I used a teleconverter with 2.8/50-135* - it's disappointing (in terms of sharpness). I tried with Bigma - in principle, not bad, but at the longest end there are the problems with focusing.

---------- Post added 29th May 2022 at 00:02 ----------

I have both. With the 150-450 use the focus limiter for fastest performance. Both the 150-450 and 70-200, are quick, concise and accurate. You should be good with either.

Thank you. Once, many years ago, thanks to the courtesy of Pentax, I tried a non-serial engineering sample 2.8 / 70-200. Alas, at that time it was clearly an unfinished product, completely ugly in terms of autofocus accuracy and speed.

[gatorguy]

Thank you. I used a teleconverter with 2.8/50-135* - it's disappointing (in terms of sharpness). I tried with Bigma - in principle, not bad, but at the longest end there are the problems with focusing.

The 150-450 is excellent across it's entire range, as is the 70-200.

[Grokh]

The 150-450 is excellent across it's entire range, as is the 70-200.

Thanks!

[UncleVanya]

Thank you. I used a teleconverter with 2.8/50-135* - it's disappointing (in terms of sharpness).

That’s odd. I’ve used the HD DA 1.4x with my DA* 50-135/2.8 and found it quite sharp.

[biz-engineer]

I have both lenses. Both 150-450 and 70-200 are similar, solid. I believe the 150-450 motor gear is slightly faster than 70-200's, at least I've had better results of AF tracking with the 150-450, I'm not sure why. In theory, the 70-200 2.8 should work better than the 150-450 thanks to it's 2.8 wide open aperture. The 70-210 is reasonably quick as well, but I missed 90% of shoots when tracking slow vintage cars on the road, I don't think it's because of the speed of AF motor, but more like K1 AF + lens combo was very bad. If the intention is to use the lens on an APSc camera, better get the 55-300 PLM, cheaper and faster to focus than both 150-450, 70-200 and 70-210.

[bdery]

HD Pentax-D FA* 70-200mm F2.8 ED DC AW Review - Focusing | PentaxForums.com Reviews
HD Pentax-D FA 150-450mm F4.5-5.6 Review - Focusing | PentaxForums.com Reviews

You beat me to it. This forum offers in-depth reviews, with AF tests you can read and compare.

[zapp]

Both Pentax lenses focus well at all apertures. I assume you wonder about good focus with small aperture glass or in low contrast. Pentax does well here, K3iii helps. Tracking of sailing boats should be no problem here.

[angerdan]

With active focus limiter, the 150-450mm is faster than the 70-200mm.
HD Pentax-D FA 150-450mm F4.5-5.6 Review - Focusing | PentaxForums.com Reviews
HD Pentax-D FA* 70-200mm F2.8 ED DC AW Review - Focusing | PentaxForums.com Reviews

Once, many years ago, thanks to the courtesy of Pentax, I tried a non-serial engineering sample 2.8 / 70-200. Alas, at that time it was clearly an unfinished product, completely ugly in terms of autofocus accuracy and speed.

You mean the FA* 80-200mm f/2.8 ED which came out 1994?
https://en.wikipedia.org/wiki/Template:Pentax_K-mount_AF_lenses_timeline

[StigVidar]

Thank you. I used a teleconverter with 2.8/50-135* - it's disappointing (in terms of sharpness). I tried with Bigma - in principle, not bad, but at the longest end there are the problems with focusing.

I agree with you regarding the converter with DA*50-135/2.8. It is not good enough. On DFA*70-200/2.8 it is a lot better. I dont use the converter with the DFA*70-200/2.8 wide open, but stop down 1 step to f/5.6 and in that case it is sharp down to pixel level on a K-3 III.