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01-20-2014, 04:20 AM   #1246
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QuoteOriginally posted by tromboads Quote
They are a hoot :P

I have a fx2 it drives you mental trying to compose in it tho honestly :P Well.. Its just a little foreign to what one is accustomed too
Yep, I just put a roll through it this afternoon.
Great fun, but it takes an eternity to get used to the left/right swap from the mirror.

01-20-2014, 04:28 AM   #1247
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Oh and just because we are talking about Ziess's



Fits the smoooooooth lines of the MZ :P
01-20-2014, 04:53 AM   #1248
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QuoteOriginally posted by Jean Poitiers Quote
There's the 44K-4 (MC-Helios 44K-4 58mm F2 Lens Reviews - Russian and Zenitar Lenses - Pentax Lens Review Database) ... I have been hunting for an inexpensive one along with a 44M-5, "6" and/or "7" ... your 44(-0), is it the 39mm/13 blade version ... ?
I would have been a lucky guy, if it was the case !

But no ! my version is the 44M in fact Helios - 44M 58mm f2 Lens Reviews - Russian and Zenitar Lenses - Pentax Lens Review Database

I know the 44k exist, but i can't find it for cheap :/

As your kind of a real soviet collector, i thought that, maybe, you would have create some K mount for those helios 44.

I think this will be another summer project, along with wet plate photography

One more thing, i was wondering if anyone "cracked" the way lens communicate data to the body (like focal lengts, etc ...) to create some custom mount and chip to save the focal lenght in the exif data when using M42 lenses ?
01-20-2014, 05:39 AM   #1249
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The SR setting gives the focal length away :P

01-20-2014, 06:33 AM   #1250
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QuoteOriginally posted by tromboads Quote
The SR setting gives the focal length away :P
not the 58mm for the 44k series, neither any 80mm, or 83mm for one of the takumar
01-20-2014, 08:24 AM   #1251
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QuoteOriginally posted by aurele Quote
One more thing, i was wondering if anyone "cracked" the way lens communicate data to the body (like focal lengts, etc ...) to create some custom mount and chip to save the focal length in the exif data when using M42 lenses ?
I agree with tromboads that typically the SR setting provides the focal length. But it would still be nice to know the aperture setting, so your idea is still interesting. I don't know anything about creating electronics, but just as a common-sense observation, I should think this would be very difficult for one simple reason: There is seemingly nowhere to put such a chip. Since the M42-to-Kmount adapter is just a tiny ring, and M42 has same film-to-flange distance as K, there is almost no space for electronics or contacts. It's in adapters with considerable front-to-back length, like from any film SLR mount to mirrorless, that you could have space for chips, contacts, and even an aperture. But maybe some hacker out there will prove my assumption wrong!

--Dave
01-20-2014, 10:35 AM   #1252
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QuoteOriginally posted by Argenticien Quote
I agree with tromboads that typically the SR setting provides the focal length. But it would still be nice to know the aperture setting, so your idea is still interesting. I don't know anything about creating electronics, but just as a common-sense observation, I should think this would be very difficult for one simple reason: There is seemingly nowhere to put such a chip. Since the M42-to-Kmount adapter is just a tiny ring, and M42 has same film-to-flange distance as K, there is almost no space for electronics or contacts. It's in adapters with considerable front-to-back length, like from any film SLR mount to mirrorless, that you could have space for chips, contacts, and even an aperture. But maybe some hacker out there will prove my assumption wrong!
SR is great, but (i dunno about newer body) on the K-x it doesn't allow to enter any value, but only preselected value (28, 35, 40, 50, 55, etc ...).

About the chip : i'm currently repairing a Sigma 28-70/ 2,8-4 Sigma 28-70mm F2.8-4 UC Lens Reviews - Sigma Lenses - Pentax Lens Review Database, the data info don't work currently because the wiring between the mount and the circuit board is cut. I'm re-wiring it and re-brazing.


The chip part is really small, and there is plenty of room between the glass and the barrel to stock everything. In fact, the biggest part is about the AF elements to tell the body the distance marking of the focusing group, when focusing (the body pre-determine where the foccus group should go, it moves, then the body re-check if the focusing is good, and can re-ask to move the focusing group accordingly).
On the picture, the biggest part of the circuitry is used for the AF system.

Hence, if anyone could decode the communication passing trough the data pin (look there to understand Features and Operation of the Kaf Mount ), i could probably make a diagram for the chip.
The chip required to communicate just a focal lenght, min and max aperture, and the name / provider of the lens, is really chip. I cost less than 1 bucks ! i think with all the wiring it can be done for 3 to 5 bucks.

All i need is an electronic engineer to can decode the communication
Any volonteer ?

Last edited by aurele; 01-20-2014 at 10:40 AM.
01-20-2014, 08:42 PM   #1253
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This was inspired by a recent Japan Camera Hunter pr0n post that Bellamy did on Facebook. I threw in all my fifty-ish lenses (50, 55, 58). I set the shot up to use the last frame of a medium-format roll at the end of a day in the field, but shot it on digi as well just in case. Glad I did; the film shot had too narrow DOF and the lenses in back were blurred! Clockwise spiral from top-right:
  • Minolta MC Rokkor-X 50/1.7 that came with my SRT102. Newer-style rubberized grip.
  • Minolta MC Rokkor PF 58/1.4 bought for use with the SRT102. Old-style solid metal.
  • Canon FD 50/1.4 from my father-in-law on his AE-1 Program. Non-breech-lock style.
  • Canon rangefinder 50/1.8 that came with my Canon P. So dinky! This is why people carry rangefinders. Great "kit lens"; it has nearly as many blades as any two of the other lenses. This is the black, not the chrome version.
  • SMC Tak 55/1.8. Came on an ESII that no longer works on electronic speeds
  • Super-Tak 50/1.4. 'Nuff said!
  • SMC M 50/2. Came on a charity shop ME Super SE. This lens is complete rubbish; I never use it (Tried it once; it's soft as hell.)
  • At center: The medium-format interloper. Nikkor-H 50/3.5 bought for use with the Bronica S2. I think you could almost fit the Canon RF 50 between the front element and second element of this thing.
That's all I have. It's a small collection compared to the dozens of 50s that some of you here have, but not completely pathetic.

--Dave


01-20-2014, 11:58 PM   #1254
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Bonjour,

"Fifties" (50mm to 58mm, or just a "true 50") ... what's "fast" in your books?

( 1.) below f2 ... independent of focal length; thus f1.2 (or lower ) to f1.9, not including f2 ( or )
( 2.) f2 and below ... and independent of focal length again ...

My question relates to the Helios 58/2's ... are they "fast" because @58mm & f2, "borderline" or not fast ...

Just curious as to your opinion(s) ... Salut, J
01-21-2014, 09:58 AM   #1255
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QuoteOriginally posted by aurele Quote
One more thing, i was wondering if anyone "cracked" the way lens communicate data to the body (like focal lengts, etc ...) to create some custom mount and chip to save the focal lenght in the exif data when using M42 lenses ?
Only way this might be done to my knowledge is to fake it:

-rejig the lens mount so the camera thinks it's an 'A' lens see for example: https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/63878-how-c...s-ka-lens.html
-you can then spin the e-dial to a particular f number and this will be recorded
-in practise the aperture is being set manually but the camera doesn't know that
How the exposures correlate could be icky..

Just a thought anyway
01-21-2014, 10:21 AM   #1256
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QuoteOriginally posted by marcusBMG Quote
Only way this might be done to my knowledge is to fake it:

-rejig the lens mount so the camera thinks it's an 'A' lens see for example: https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/63878-how-c...s-ka-lens.html
-you can then spin the e-dial to a particular f number and this will be recorded
-in practise the aperture is being set manually but the camera doesn't know that
How the exposures correlate could be icky..

Just a thought anyway
i have thought of it too, but it's more the focal lenght and name of the lens that i would like to record, and for that i need to understand how work the communication between the lens and body by the lowest pin on the mount.
01-21-2014, 10:29 AM   #1257
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QuoteOriginally posted by aurele Quote
i have thought of it too, but it's more the focal lenght and name of the lens that i would like to record, and for that i need to understand how work the communication between the lens and body by the lowest pin on the mount.

Whole different ball game. I vaguely remember reading some stuff by minolta enthusiasts who had done st similar chipping old rokkor lenses...
01-21-2014, 01:02 PM   #1258
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QuoteOriginally posted by aurele Quote
not the 58mm for the 44k series, neither any 80mm, or 83mm for one of the takumar
Exiftool is your friend. I use it for my scanned images and occasionally for those from the K10D.


Steve
01-22-2014, 01:43 AM   #1259
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QuoteOriginally posted by stevebrot Quote
Exiftool is your friend. I use it for my scanned images and occasionally for those from the K10D.
Yeah i know, but i'd love to work a bit the mount thing to avoid this pain every single time i take pictures.
01-22-2014, 05:06 AM   #1260
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QuoteOriginally posted by aurele Quote
Yeah i know, but i'd love to work a bit the mount thing to avoid this pain every single time i take pictures.
I agree, that would be génial as it would avoid the effect of SR-induced motion blur because I forget setting the focal length when changing from 16mm to 125mm!
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