Limited DX Coding Range in Compact Cameras.

[BobUK]

I have never had a camera that used DX Coding. All of mine have been manually set film speeds. So I have never had this problem before.

At the moment I'm looking at a Samsung AF Slim Zoom going for a reasonable price. It has DX coding and apparently no manual ISO setting.



Now for the interesting bit.

After testing for my personal film speeds and developing times, some of my speeds fall between the standard box speeds given by the film manufacturers.

I thought of using self adhesive DX Code labels to set the camera to my true ISO speeds. But, apparently most, if not all of these DX Coded point and shoot cameras are programmed with only about four or five standard box speed settings available from a theoretical range of twenty four.

I have looked through quite a few instruction manuals at Butkus for different cameras, but they say things like "Automatic setting with DX Coded films ISO 50 - 3200" or whatever the range is for that particular camera. No mention of the actual available steps built into the camera.

Apart from makers instruction manuals that do not touch on this subject, is there any source that reveals the limited range of DX Codes available on the various cameras?

Thanks in advance for any advice.

 

[4season]

I don't know of such a listing, but you might be able to spot clues based on how many electrical contacts the camera has. A Canon EOS that I checked as a single row of 6 contacts, so it can detect ISO but not film length via DX coding. But it nevertheless detects film length by unspooling the entire roll, then advancing film backwards.

On the other hand, my Zenit 412 (not 412LS) has just three contacts, and IIRC, it detects ISO up to 400.

More regarding DX code are here:
https://en.wikipedia.org/wiki/DX_encoding

 

[Paul Howell]

I have the same problem. my E.I for the films and developers I use do not match box speed, when I use a point and shoot I process black and white as a push.

 

[Cholentpot]

I use tape and scratch to make my own DX codes.

To be honest I don't think dialing in the exact ISO does anything for these point and shoots. I'm convinced they take a more sledgehammer approach to exposure. Overexpose when in doubt kind of thing.

 

[koraks]

After testing for my personal film speeds and developing times, some of my speeds fall between the standard box speeds given by the film manufacturers.

But since these P&S cameras generally have rather crude metering systems anyway, I wouldn't worry about it and just round down (assuming negative film) to the nearest 'whole' ISO rating.

 

[MattKing]

Even if the metering system in these cameras wasn't technologically crude, it certainly doesn't make use of a carefully positioned spot function - in fact, it is usually difficult to pin down what it is pointed at. So I agree with the advice above.

 

[Cholentpot]

I have a few later model point and shoots that do have a dedicated spot meter setting but I'm still not convinced that it does anything. The camera does what it wants, focus and exposure be darned.

 

[xkaes]

I won't dispute what has already been said, but what I'd look for, as mentioned, is the number of pins in the film chamber. If there are six, then the camera could handle film from 25 to 5000 ISO. The maker of the camera would not add extra pins if they didn't do something.

 

[mshchem]

My point and shoot. Available used for under 300 usd