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10-19-2016, 01:27 AM   #4576
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QuoteOriginally posted by stevebrot Quote
I believe you read a mildly inaccurate account that does not apply to your Program Plus. Here are the pertinent points:
  • The KA mount specification supports f/2.5, but not f/2.4 (see link below to the contact mapping scheme on Dimitrov's K-mount site).
    Features and Operation of the Ka Mount
  • P and A-series Pentax bodies correctly use f/2.5 as the maximum aperture in both P and Tv modes when used with f/2.5 maximum lenses. I don't have experience with the autofocus bodies.
  • For some unknown reason, current Pentax dSLRs treat f/2.5 lenses as if f/2.4 were available. This is true for all f/2.5 lenses, not just the PKA Adaptall-2. On those bodies, f/2.5 is available in both Av and M mode if exposure stops are set to 1/3 increments (the default). Unfortunately, so is f/2.4...go figure. For 1/2 stop increments, f/2.4 alone is available.
  • F/2.5 is 1/3 stop wider than f/2.8 (part of 1/3 stop sequence)
  • F/2.4 is 1/2 stop wider than f/2.8 (part of 1/2 stop sequence)
  • F/2.4 is 1/6 stop wider than f/2.5
  • If the camera attempts to set f/2.4 on a f/2.5 lens, the resulting exposure will be 1/6 stop less than the stipulated EV. This is only true if the body attempts f/2.4 as maximum aperture on an f/2.5 lenses.
  • Since f/2.4 it is not supported by the mount, it is not possible to "hack" or modify a mount to report f/2.4 maximum aperture. It is possible to make the lens report as f/2.8 maximum by masking the lens contacts to the f/2.8 pattern. With an Adaptall-2 lens this may be accomplished by changing the position of the aperture index tab on the lens aperture ring.

In regards to metering and general usage with the brand-X vs. the genuine Tamron adapters, the bottom line may be expressed in a few points:
  • If you want full exposure and aperture automation and accurate metering on all Pentax K-mount bodies, get the PKA adapter
  • If you want aperture automation, full support for standard K-mount cameras, and are willing to accept the short falls of metering with the crippled mount bodies*, get the PK adapter
  • If you are happy with stop-down metering and willing to accept poor metering with modern crippled mount bodies and are happy with fully manual aperture, get the brand-X
Given that PK adapters are cheap and readily available, I see no reason to go with the brand-X with a camera such as your Program Plus, but to each his own.


Steve

* Meter variance of up to 2 stops over/under from the expected, depending on aperture and lens.
Yeah, but I bought the 01BB as a 35mm FOV equivalent for my K-S2 in the first place, and using it on my Program Plus as a 24mm ultra wide is its minor usage.

Given up aperture automation in turn gives me the option of aperture priority on DSLRs when a KA adapter is cost prohibitive.

Sent from my Android phone, please forgive any possible typos.


Last edited by butangmucat; 10-19-2016 at 01:37 AM.
10-19-2016, 07:30 AM - 4 Likes   #4577
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Cross-posted to https://www.pentaxforums.com/forums/7-pentax-compact-cameras/330998-point-sho...ml#post3789797



It was hard to get a clear shot with my phone, and if I set it up again with a tripod I will rearrange.

Top row: Bronica S2 Nikkor 75mm/2.8, Canon Serenar 85mm/2 LTM, Bronica S2 Nikkor 50mm/3.5, Pentax 67 105/2.4
Second row: Sigma 24mm f/2.8 PK, Jupiter-8 50mm/2 LTM, Olympus Pen 38mm f/1.8, Leica Summitar 50mm/2, Mamiya C 180mm f/4.5
Third row: Lensbaby 50/2 PK, Sears 135/2.8 PK, Pentax 67 45mm/4, Voigtlander Color-Skopar 35mm f/2.5 LTM, Mamiya C 80mm f/2.8
Fourth row, Tokina AT-X 28-70mm/2.8 PK, Pentax 6x7 165mm/2.8, Bronica S2 Nikkor 135/3.5, SMC-Pentax FA 50mm/1.4
10-19-2016, 08:17 AM   #4578
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QuoteOriginally posted by unixrevolution Quote
Cross-posted to https://www.pentaxforums.com/forums/7-pentax-compact-cameras/330998-point-sho...ml#post3789797



It was hard to get a clear shot with my phone, and if I set it up again with a tripod I will rearrange.

Top row: Bronica S2 Nikkor 75mm/2.8, Canon Serenar 85mm/2 LTM, Bronica S2 Nikkor 50mm/3.5, Pentax 67 105/2.4
Second row: Sigma 24mm f/2.8 PK, Jupiter-8 50mm/2 LTM, Olympus Pen 38mm f/1.8, Leica Summitar 50mm/2, Mamiya C 180mm f/4.5
Third row: Lensbaby 50/2 PK, Sears 135/2.8 PK, Pentax 67 45mm/4, Voigtlander Color-Skopar 35mm f/2.5 LTM, Mamiya C 80mm f/2.8
Fourth row, Tokina AT-X 28-70mm/2.8 PK, Pentax 6x7 165mm/2.8, Bronica S2 Nikkor 135/3.5, SMC-Pentax FA 50mm/1.4
Nice collection!

Phil.
10-20-2016, 07:01 AM   #4579
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Hi guys ... I have a Minolta question to ask.

My black XD-7 has decided to break about the rewind crank (grrrrr) and while waiting to pick a possible parts body, I found an ad for an XE-1. Curious, and seeing an excuse, I bit.

It was not to expensive, but I think that I got ripped off ... everything works, but the film crank lever will to rise up in order to open the film door (!) ... never seen this before.

So I removed the base plate in order to open the body ... all looks fine and the lever spindle rotates rather freely with a bit of resistance. I did a minor dissemble about the rewind crank, but abandoned and reassembled after seeing no issues. Was pretty sure that I would not see anything, but you never know ...

Anyone ever come across a problem like this or have a possible suggestion (?) ... I am at a loss of ideas for the moment and taking a pause with this problem.

The "rip off" bit is that the seller will not reply to my messages and that I paid by check ... this is the first time for an incident like this, which is frustrating, but not the end of the world.

Any help would be appreciated ... Merci, J

10-20-2016, 08:35 AM   #4580
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You lift the rewind lever to open the back. That's how this camera works, same with my old Minolta.

How to use the Minolta XE-1 / XE
10-20-2016, 09:30 AM   #4581
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QuoteOriginally posted by Archimedes the Dog Quote
You lift the rewind lever to open the back. That's how this camera works, same with my old Minolta.

How to use the Minolta XE-1 / XE
Thanks for your post.

No, as I wrote, it's blocked and will not raise/lift at all ... thus the film back will not open via the normal rewind crank maneuver.

Again, I removed the bottom base plate and released the film door from the interior of the bottom of the XE-1 camera body. It's easy to do.

I would load film this way, but since the rewind prong of the crank is down and will not move normally upwards, it's not possible to load a film cartridge.

Salut, J
10-20-2016, 10:13 AM   #4582
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QuoteOriginally posted by Jean Poitiers Quote
but the film crank lever will to rise up in order to open the film door (!) ... never seen this before.
There is a crucial typo there.
10-22-2016, 11:12 AM - 2 Likes   #4583
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10-22-2016, 12:08 PM   #4584
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^^^ Yummy - the camera and lens, both
10-23-2016, 05:56 AM   #4585
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Very nice 6x7!
10-23-2016, 05:59 PM   #4586
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QuoteOriginally posted by unixrevolution Quote
Very nice 6x7!
I got this camera as a parts body 7 years ago. I had Eric repair it and it's been a great camera for me. I started out with just a 45mm and 90mm LS, now I have 45, 90, 105, 200, and WLF and original Pentax strap. I'm thinking about adding the 75/4.5
10-23-2016, 06:46 PM   #4587
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QuoteOriginally posted by Swift1 Quote
I got this camera as a parts body 7 years ago. I had Eric repair it and it's been a great camera for me. I started out with just a 45mm and 90mm LS, now I have 45, 90, 105, 200, and WLF and original Pentax strap. I'm thinking about adding the 75/4.5
I just sold my 75mm, I found I never, ever used it because I also have the 45 and why wouldn't I use the 45?

I also have the 105 and the 165mm f/2.8, and I love all three lenses. I am considering adding the 300/4 at some point.
10-23-2016, 07:42 PM   #4588
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QuoteOriginally posted by Swift1 Quote
So tempted to pick one of these up at some point...
10-23-2016, 07:53 PM   #4589
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QuoteOriginally posted by nickthetasmaniac Quote
So tempted to pick one of these up at some point...
You really should. It's my favorite film camera of all time.
10-23-2016, 08:07 PM   #4590
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QuoteOriginally posted by unixrevolution Quote
I just sold my 75mm, I found I never, ever used it because I also have the 45 and why wouldn't I use the 45?

I also have the 105 and the 165mm f/2.8, and I love all three lenses. I am considering adding the 300/4 at some point.
I borrowed a friend's 75/4.5 very briefly last year. I really like the images I got with it. My favorite focal length for 135 format is 35mm, so 75 makes some sense.
Lately I've just been using my 45 and 200 though

---------- Post added 10-23-2016 at 08:08 PM ----------

QuoteOriginally posted by nickthetasmaniac Quote
So tempted to pick one of these up at some point...
They're great cameras. Big though
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