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Forum: Pentax News and Rumors
09-28-2021, 01:21 PM
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Forum: Pentax SLR Lens Discussion
09-05-2021, 01:37 AM
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Hi Bernard,
firstly, I am not an owner of 16-50 PLM but maybe you'll find my post somewhat useful.
My opinion is based on short experiences with 55-300 PLM and some technical knowledge.
For PLM Pentax lenses, manual focusing is done as "focus by wire" technique. It means that manual focus ring has no mechanical with the optics.
This kind of solution is very common on mirrorless camera lenses - most probably with the ones featuring linear motor (PLM in Pentax lenses has that kind of focusing motor).
The consequences from that solution are:
When camera is turned off, you are not be able to focus with your lens (some people are doing this, i don't know why but that not a point of discussion... just keep in mind the limitation).
There may be no "exact" amount of rotation for focusing from infinity to minimum focus distance (MFD)... well it depends on manufacturer implementation... there are two ways:
* Non-linear focusing - the factor is a movement of focusing ring but also a speed of that movement.
The faster you move the ring the bigger change is applied to focusing (even if you made the same distance rotation).
I know it does sound crazy, but it's possible... because there is no mechanical link between - the movement of the ring is just detected by electronics probably.
* Linear focusing - the only factor is a movement of focusing ring - not just speed, so regardless you move the ring fast or slow - if you make a same amount of rotation, the focus should be more or less in a same place. In most cases, linear focusing is important when for video.
Edit: it is far better described here -> https://www.reddit.com/r/videography/comments/o98p8e/dont_buy_a_lens_without...this_focus_by/
The only point I would disagree with the article in the link is about the "hard stops".
Slso the issue with manual focus may be true or not (there's no mention about linear setting in some cameras), depending on camera implementation.
Some cameras like have a possibility to choose which way the manual focusing should be done - non-linear or linear (it's just a software setting).
Regarding the Pentax camera's I don't know which way is implemented since I spent very little time with 55-300 PLM.
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Forum: Sold Items
05-03-2021, 07:46 AM
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Hi there,
I am interested of buying Pentax Super Program. PM Sent
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Forum: Pentax News and Rumors
04-16-2021, 02:07 AM
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As the Ricoh mentioned, the focusing algorithm has been optimized while using these lenses (also SMC ones).
I have tested all lenses in the late evening, in dim lit room (ISO 1000-1600, SS about 1/100, lenses wide open).
Before the update, the 31 was the least accurrate - while now there's a big improvement on KP. 77 and 43 seem to work better too.
Even the old FA* 85 seem less quirky in it's focusing, but it's not as big change as in case of the FA Limited trio.
50-135 works nicer and more precise during focusing without a "half-stops" (some micro readjustments before final "locking" on the target) as it happened before.
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Forum: Pentax News and Rumors
04-15-2021, 07:55 AM
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Hope my beauties will be even better with KP :)
The 31 was focusing the least accurrate from the trio.
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Forum: Pentax K-3 III
04-07-2021, 11:57 PM
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Welcome in the pentax community :D
I see it seems to be working, but camera tracks eye with some kind of latency - it looks as latency at least.
Do you know maybe what is the longest distance between person and camera where eye tracking works?
I think it does depend on selected lens.
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Forum: Pentax News and Rumors
02-03-2021, 04:48 PM
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Little on expensive side but... I saw it's extraordinary lens in terms of sharpness and distorsion. The shift lens that K-mount doesn't deserve - but I hope it will get :)
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Forum: Pentax News and Rumors
01-16-2021, 04:10 PM
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Yeah, it seems to be a new Laowa 15 f/4.5 Shift Zero-D - a different one, than existing Laowa 15 f/4 Shift (non Zero D).
While checking the lens product website, I haven't found a Pentax K option (EF and F mount available, E and Z mount soon).
I wonder if the guy from video adapted the lens using Leitax adapting kit or it's time to start another rumor :D ?
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Forum: Pentax SLR Lens Discussion
08-11-2020, 11:55 PM
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Tamron SP 70-200 2.8 Di LD has a good bang for a buck, though it is sometimes soft at 200mm wide open.
This seems to be typical issue of this lens. A friend of mine, has sent his copy to technical service and after that, the lens was nearly as sharp as DFA* 70-200,
although with noisy, lower autofocus performance and bit worse bokeh. I wouldn't consider this flaws too much, the lens is worth enough it's money for a portrait work.
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Forum: Welcomes and Introductions
08-11-2020, 12:17 PM
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Hi there,
I am computer science student from Poland.
I've been watching this forums for about year or two. Mostly looking for new pentax related rumors and news.
I was fighting with myself if register there or not, mostly because If I start a discussion, I cannot stop it and go away to do other stuff.
Anyway, the time has come to say "hi". I bought (it's used but, a new lens for me) a silver 77 1.8 MIJ limited, it does need a spare AF gear, so that's why I am here.
Sorry for my poor english :)
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