[butangmucat]

Hello,

I would like to know if MZ-M will actually read the part of DX on a film cassette that indicates the number of exposures. The reason is that I have bought some respooled Vision 3 5207 film (the 250D, which does not have a CineStill version). The seller told me that the cassettes come from expired film, so the DX coding could be anything, and Canon EOS cameras tend to rewind prematurely if a cassette indicates the number of exposures to be less than 36.

Sincerely

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[pschlute]

Had a quick look at the MZ-M manual and it does not appear to have a setting to disable auto-rewind. Having said that I was not aware the DX code triggered the rewind. Think you will have to experiment !

You will also need to set the ISO manually.

http://www.cameramanuals.org/pentax_pdf/pentax_mz-m.pdf

[Alex645]

I canʻt think of any reason why any DX equipped camera wouldnʻt read or ignore the exposure length info on the DX marked cassette. The answer to your question is YES.

Hereʻs a link to DIY DX labels:

DIY Film DX Code Labels: 4 Steps (with Pictures)

And more details about how to de-code DX:
DX encoding - Wikipedia

Just check that the actual amount of exposures on the DX coded cassette matches the DX label. Unless someone DIY the loading of the wrong cassettes with the wrong DX info, you shouldnʻt have a problem.

[AstroDave]

Just check that the actual amount of exposures on the DX coded cassette matches the DX label. Unless someone DIY the loading of the wrong cassettes with the wrong DX info, you shouldnʻt have a problem.

Or, just cover up the bad code(s) (tape or paint over) - or make a new one that matches your film length, and paste it over the bad stuff. I never had a camera that used the codes, but I presume if you had a roll of uncoded film that the camera would work anyhow (you just had to set ASA/ISO and remember when to quit advancing the film).

[butangmucat]

I asked because from what I know, my (now dead) Contax 167MT does read DX, but only for film speed. The rewind is triggered manually, and the camera simply refuses to cock the shutter and advance anymore when the end of a roll is reached (yes the camera has motor wind and rewind built in). I regularly gets 37 to 38 shots on a 36 shot roll with that camera. I know that MZ-M auto rewinds, but am not sure does the DX trigger it or the change in film tension triggers it.

Sincerely

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---------- Post added 01-15-18 at 09:42 PM ----------

I canʻt think of any reason why any DX equipped camera wouldnʻt read or ignore the exposure length info on the DX marked cassette. The answer to your question is YES.

Hereʻs a link to DIY DX labels:

DIY Film DX Code Labels: 4 Steps (with Pictures)

And more details about how to de-code DX:
DX encoding - Wikipedia

Just check that the actual amount of exposures on the DX coded cassette matches the DX label. Unless someone DIY the loading of the wrong cassettes with the wrong DX info, you shouldnʻt have a problem.

Or, just cover up the bad code(s) (tape or paint over) - or make a new one that matches your film length, and paste it over the bad stuff. I never had a camera that used the codes, but I presume if you had a roll of uncoded film that the camera would work anyhow (you just had to set ASA/ISO and remember when to quit advancing the film).

Yeah that's what the seller suggested if I am in question. The cassettes comes from expired film, and the respooled Vision 3 is taped to the end section of the expired film so the cassettes can be reused without being opened. Therefore there will always be one exposed frame at the end of the respooled film, and the DX code can mean anything but ISO 250, 36 frames.

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[TwoUptons]

I don’t think the ZX-M has enough contacts to read the second row of the DX. I looked at a photo of a ZX-3 online, and it doesn’t (and I can check the ZX-L when I get home).

I think it just winds until it gets to the end and then rewinds based on increased tension.

I rolled my own film 20 years ago with a PZ-20, and it worked out fine (38-40 exposures on a roll).

I think the camera only ripped off the film where it was taped to the original roll once... and that was fixed with a changing bag and more careful taping on future rolls...

-Eric

[stevebrot]

The seller told me that the cassettes come from expired film, so the DX coding could be anything

There is your answer. Cover the code on the cassette with non-conductive tape and set the ISO manually. Your camera is designed to support both DX and non-DX cassettes so I would not sweat the end-of-roll concern unless the seller was lax in securing the tail end to the spool.


Steve

[johnha]

DX film coding was originally developed to help the lab processing machines work out what they were processing. The number of shots helps the lab work out many prints to charge for. I don't know any Pentax 35mm film cameras that rewind the film based on the DX code - they all sense the film advance motor stall and respond to that.

John.