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12-07-2014, 02:13 PM   #4816
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QuoteOriginally posted by LensBeginner Quote
What are the advantages of doing that? the main thing of having a Pentax A lens - at least for me - would be finally having the aperture data in the EXIF (writing it by hand really gets tedious...), but since there's no contact I guess there must be other benefits?

I think that allows shooting in Av mode with an M lens while still being able to change the aperture.

12-07-2014, 02:39 PM   #4817
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QuoteOriginally posted by Tsuken Quote
I think that allows shooting in Av mode with an M lens while still being able to change the aperture.
Would it also allow all metering modes as well? (not just center-weighted)
12-07-2014, 04:18 PM   #4818
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QuoteOriginally posted by Tsuken Quote
I think that allows shooting in Av mode with an M lens while still being able to change the aperture.
I don't get it... the benefit of Av mode is that you get an immediate change in the shutter speed when you change aperture... the way you do it, it looks like you still have to press the green button..?
12-07-2014, 06:41 PM - 1 Like   #4819
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To answer the questions, the "A" lens hack with foil allows ALL auto-exposure modes, including P-TTL flash use. It's not perfect but is sometimes a worthwhile convenience.

Here is my 3-year-old granddaughter performing at Dixie Stampede in Branson, MO yesterday.

(K100DS, ISO1600, Pentax-M 50mm f1.7 @ f2.8)

-Joe-


Last edited by k0og; 12-07-2014 at 06:52 PM.
12-07-2014, 08:06 PM - 1 Like   #4820
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QuoteOriginally posted by k0og Quote
To answer the questions, the "A" lens hack with foil allows ALL auto-exposure modes, including P-TTL flash use. It's not perfect but is sometimes a worthwhile convenience.
To clarify the "not perfect" part, on K- and M-series Pentax lenses, a given amount of movement of the diaphragm actuator changes the aperture diameter by a proportional amount. But in A-series and later lenses, a given amount of movement of the diaphragm actuator is proportional to the difference in the number of stops. Which is to say, using a K- or M-series lens with this hack will give increasingly inaccurate exposure as the lens is stopped down.
12-08-2014, 02:04 AM   #4821
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I took photos at the 'switch-on' ceremony of my Town's Christmas Lights and used my 35-80mm f4-5.6 SMC Pentax-F series for all except this one where I switched to my trusty 75-150mm f4 SMC -Pentax -M lens at full aperture.
12-08-2014, 09:13 AM - 1 Like   #4822
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I ve been really enjoying my SMC M 50mm f1.4, ...



12-08-2014, 02:03 PM   #4823
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QuoteOriginally posted by LensBeginner Quote
I don't get it... the benefit of Av mode is that you get an immediate change in the shutter speed when you change aperture... the way you do it, it looks like you still have to press the green button..?

I wouldn't think so. I haven't bothered with this (I usually just estimate exposure when using my M lenses, and that usually works fine), but I would expect the idea is that Av works just as you'd expect; stop-down metering with the green button works without doing that mod.
12-08-2014, 02:30 PM   #4824
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focus problems with 50mm f1,4 ?

Hello everybody...

I hope that i am posting in good thread : i recently bought pentax smc M 50mm f1,4. I use it on my K5 : M mode, with Manual focus selected -

Up to now i used it only in inside condition, at f1,4 and f2. Unfortunately almost all my photos are not clear : when i take photo, focus seems to be perfectly clear on face of subject for example (my eyes see a perfectly clear scene with focus on people face for example) but when i watch photos on computer, almost all are blurr with face not clear. Usually subject is situated at about 1 meter from me.

Is it possible that lens suffer from trouble ? Or just consequence of very small DOF with 50mm f2 ? Can we speak of front / back focus with manual lens or maybe i use this lens in bad conditions ?

Could people in this forum explain me how they manage this 50mm f1,4 lens ?

Thanks in advance !!

Lionel

Pentax K5 + samyang 14mm + DA ltd 40mm + DA ltd 70mm + pentax M 50mm f1,4 + pentax 100-300(4,7-5,6) + sigma 18-35 f1,8
12-08-2014, 02:36 PM   #4825
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If it seems in focus in your viewfinder, but photos turn out out-of-focus, try adjusting your diaopter above the viewfinder.
12-08-2014, 02:44 PM   #4826
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When I started using faster lenses and focusing manually, I had the same issue -- things that looked in focus in the viewfinder were way off in the actual output. In my case it was a couple of things. First of all, the stock focusing screen is optimized for slower lenses, and doesn't show just how narrow the depth of field is at f/2 or f/1.4. (The DOF you see in the viewfinder is somewhere around f/3.5, in my experience.) I changed for one of the S-type screens from focusingscreen.com and I love it.

Second problem I had was a mis-aligned focusing screen. Before I changed to the S-type screen, I temporarily shimmed the stock screen with some strips of Post-It note, and this fixed the issue.

I don't know if either of these is affecting you, but that is at least a couple of things to look into.
12-08-2014, 03:03 PM - 2 Likes   #4827
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Love my M50 1.7, some pics taken with it;
12-08-2014, 04:57 PM - 2 Likes   #4828
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K5IIs+M150mm f3.5 (f8), Galata Bridge and Beyazıt Tower ( Actually design fire-watch tower but It is currently equipped with lighting system to indicate weather conditions in different colors. Red colour means snow, blue - nice and clear weather, green - rain and yellow - fog.), Istanbul

12-08-2014, 07:58 PM   #4829
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QuoteOriginally posted by turkiye2turkiye Quote
K5IIs+M150mm f3.5 (f8), Galata Bridge and Beyazıt Tower ( Actually design fire-watch tower but It is currently equipped with lighting system to indicate weather conditions in different colors. Red colour means snow, blue - nice and clear weather, green - rain and yellow - fog.), Istanbul

beautiful.
12-09-2014, 02:50 AM   #4830
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QuoteOriginally posted by baro-nite Quote
When I started using faster lenses and focusing manually, I had the same issue -- things that looked in focus in the viewfinder were way off in the actual output. In my case it was a couple of things. First of all, the stock focusing screen is optimized for slower lenses, and doesn't show just how narrow the depth of field is at f/2 or f/1.4. (The DOF you see in the viewfinder is somewhere around f/3.5, in my experience.) I changed for one of the S-type screens from focusingscreen.com and I love it.

Second problem I had was a mis-aligned focusing screen. Before I changed to the S-type screen, I temporarily shimmed the stock screen with some strips of Post-It note, and this fixed the issue.

I don't know if either of these is affecting you, but that is at least a couple of things to look into.
I will watch if i did not change by mistake diaopter ....

Changing focusingcreen seems to be a difficult operation..i'm afraid about doing it....i will try to make various test with this lens before....

Lionel
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