Altering DX codes then push/pull does it work ?

BADGER.BRAD

BADGER.BRAD

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Hello all,

Has anyone ever tried altering DX codes then push/pulled the film to suit ? What were the results ? was it worth it ? I have a couple of point and press cameras that only recognize 100 and 400 ASA altering Aperture dependent on DX code . I thought about cheating and using cheapo 200 speed film but fooling the camera to think it's 400 to get the larger depth of field ?

Thanks all
 
What focal length is the lens on the point and shoot and the F number/

Can't see one stop is going to make a massive difference to the dof? maybe a couple of paces forward or back from the subject might make as big a difference?
 
Firstcall sell these labels at £2.99 for 5, plus what looks like a scary amount for postage, so you'd need to work out the total additional cost per film and compare it to more expensive 400 film. Rating 200 at 400 means underexposing the film by 1 stop, which should be within the latitude of print film. It is unlikely to give as good results as exposing it at 200, but that might be worth chancing it to see. I've found that Poundland Agfa 200, Agfa Vista 400 and Kodak Colourplus 200 all appreciate a decent amount of light, and I'd not want to underexpose any of them unless I didn't have a choice.
https://www.firstcall-photographic.co.uk/firstcall-dx-recoder-labels-iso-400/p747
 
Peter B said:
Poundland Agfa 200,
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Peter B said:
I'd not want to underexpose any of them
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I don't have examples to hand ( they've been posted on TP more than once in the past), but I've pushed vista 200 to 1600, devd at home with tetenal kit and had vg results.

I no longer shoot colour so I'm rapidly falling out of touch with colour films therefore I probably don't have a clue what I'm talking about ( as usual!) :LOL:
 
Asha said:
I don't have examples to hand ( they've been posted on TP more than once in the past), but I've pushed vista 200 to 1600, devd at home with tetenal kit and had vg results.
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Did you just dev them for the standard time Asha, or did you change anything?
 
Peter B said:
Did you just dev them for the standard time Asha, or did you change anything?
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Tbh it's quite some time ago and I don't have the details handy but from memory I think the C-41 developing time was extended slightly ( iirc there was advice in the tetenal kit instruction booklet on pushing development) although I seem to recall that the "push" duration wasn't much different to the standard. That itself gave me doubts that the results would be succesful, but they were.
 
I’ve hacked the DX code on the canister so I could overexpose some expired film in a DX enabled point-and-shoot, but I didn’t push or pull it in development. You don't need to buy labels, just scrape off the black paint to uncover the metal, or cover the metal with some non-conductive material as required.

There's an article about it here: https://www.japancamerahunter.com/2014/04/hack-film-change-dx-coding/

And a full chart of the codes here: https://en.wikipedia.org/wiki/DX_encoding#Reading_DX_codes
 
If your camera only recognises a limited range of values, it's likely that it only reads 2 bits of the strip as detailed in the wiki article. Therefore just a bit of tape over one side of the strip will fool the thing into accepting 200 as 400 ASA.
 
This seems more trouble than it's worth when you can just buy 400 ISO film for a reasonable price (and not be charged for labels or push processing), or buy a compact P&S like a Canon Sureshot Supreme that will read the ISO 200 code correctly for about the same price as a single film and processing. Without any adjustment in processing, colour print film underexposed by a stop (e.g. 200 exposed as 400) is generally far from ideal, while film overexposed by a stop (e.g. 200 exposed as 100) will probably be fine. Some (but certainly not all) cameras default to ISO 100 with uncoded film, so simply covering the whole code with a generic label may work; otherwise you can carefully cover the first 'bit' to turn the 200 code into 100. This will give you less DOF, of crouse, but it hardly seems worth bothering about that with the sort of simple camera that doesn't implement full DX decoding.
 
Thanks everyone, much appreciated. The cameras I have ( various electonic point and shoots) have I think been designed for taking holiday style portraits and although they have limitations I do enjoy using them and they are very tough, they were part of a collection of cameras which I inherited from my dad and I can remember using them as a teen. In the past I've only ran Kodak colourplus 200 ASA film through which it recognizes as 100 ASA so was fine, this gives an aperture of 3.6 ish ( 400 would give an aperture of 5.6.
For most of my photography I like to be able to see all the detail in the back ground so that I can look at the image and see other bits of interest rather than just the main subject ( hope that makes sense) I think as pointed out I am flogging a dead horse with these cameras and am probably better sticking with the other smallish Cosmic cameras from Lomo that I have more control over.
 
BADGER.BRAD said:
Hello all,

Has anyone ever tried altering DX codes then push/pulled the film to suit ?
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I'm not entirely sure that I'm understanding you.

Pushing and pulling refer to adjustments in development, not exposure. You don't need to alter DX codes if you only intend to push or pull the film in development.

If you want to over or under expose the film when taking the photos, however, then some cameras without manual controls might require alteration of DX codes to do so.

Are you planning to over/under expose when taking the photos, push/pull when developing the film, or both?
 
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Hello skysh4rk,
The camera only has two aperture settings theses are controlled dependent on the dx code of the film 100 ASA for an aperture of 3.6 and 400 ASA will give an aperture of 5.6 I was purely trying to gain a smaller aperture to get an improved depth of field whilst still using cheap film £2.49 for 36 exposure rather than 5 to 10 pounds but as pointed out the higher development costs would out do any savings on film. I've just dug out one of my Russian Cosmics and found a used black and white film which I had forgotten about but the intention is to use one of them instead as I can control the camera myself.
 
Guessing at an FL of 35mm and using f/4 rather than f/3.6, I had a look at dofmaster and came up with 18'3"-infinity at f/4 and 14'11"-infinity at f/5.6 at a 40' focussing distance - not a huge difference. At a closer distance (10'), the figures are 7'9"-14'2" and 7'1" to 17'2".
 
BADGER.BRAD said:
Hello skysh4rk,
The camera only has two aperture settings theses are controlled dependent on the dx code of the film 100 ASA for an aperture of 3.6 and 400 ASA will give an aperture of 5.6 I was purely trying to gain a smaller aperture to get an improved depth of field whilst still using cheap film £2.49 for 36 exposure rather than 5 to 10 pounds but as pointed out the higher development costs would out do any savings on film. I've just dug out one of my Russian Cosmics and found a used black and white film which I had forgotten about but the intention is to use one of them instead as I can control the camera myself.
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Okay, so you're looking to alter the DX code in order to manipulate the camera's aperture and then you're looking to push to compensate for underexposing your ISO 200 film?

I've experimented with pushing a number of films and it can work, but I find it's ordinarily better just to get the appropriate speed film unless you have no other options available.
 
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