I'm trying to fool my P&S. Help!

[Vics]

I really like my newly aquired Canon Sure Shot Supreme, but I'd like to shoot Tri-X at ISO 320. Does anyone know a trick for fooling this automatic camera? Thanks in advance.

[Greyscale]

You can follow this thread at APUG concerning creating custom DX labels.

http://www.apug.org/forums/forum172/...cassettes.html

Info on DX configuration:

http://bythom.com/dxcodes.htm

[Lord Nikon]

1234567890

[sepiareverb]

I don't know this camera, but the Contax TvS had a sensor in the face of the camera I used to cover with some ND gel to skew ISO.

[btgc]

I'm afraid most P&S cameras, at least ones not prohibitively expensive, don't read intermediate ISO values and either revert to ISO100 or closest lower value.

Suggestion to cut amount of light reaching sensor is good one, in days before I had adjustable camera I thought I could select several "filters" to trick AE brain but rather bought other camera.... Probably strip of not exposed and processed BW film would make variable density filter for this? I'll try this when I load some camera without control over exposure.

[Thardy]

Here's an article on Wikipedia that shows the dx coding on film cartridges.

http://en.m.wikipedia.org/wiki/DX_encoding#section_4

[Vics]

Thanks for all the replies! I think I'll start with a bit of film over the sensor. Failing that, I'll live with it. That's what Leicas are for.

[loquax ludens]

Porter's still has some ASA 40 and ASA 125 DX coded film canister labels for sale. No 320, unfortunately.

[Greyscale]

Originally Posted by btgc

Suggestion to cut amount of light reaching sensor is good one, in days before I had adjustable camera I thought I could select several "filters" to trick AE brain but rather bought other camera.... Probably strip of not exposed and processed BW film would make variable density filter for this? I'll try this when I load some camera without control over exposure.

I don't know if you would need a filter, probably just a piece of black tape with a small hole cut in it to make a smaller iris for the sensor would work.

[David Hughes]

Hi,

Count the number of DX contacts in the cassette chamber. If there's only four, which is normal, then give up as 4 contacts means 100, 200 and 400 ASA/ISO only.

Regards, David

[John Bragg]

This is a cassette re-coded by me to fool my camera into rating it at ei200. I call it the scrape and tape method. It is easy to use a modelling knife to carefully remove some segments and tape to make new ones. Two minute job, tops.

Good luck.
John.

[btgc]

Originally Posted by Greyscale

I don't know if you would need a filter, probably just a piece of black tape with a small hole cut in it to make a smaller iris for the sensor would work.

Yes, let's imagine pouch with pre-cut pieces of film or bits of tape with holes of different sizes?

- what are you doing with this, is this new kind of school drugs?
- nope, this is to fool exposure meter!

[Vics]

Originally Posted by John Bragg

This is a cassette re-coded by me to fool my camera into rating it at ei200. I call it the scrape and tape method. It is easy to use a modelling knife to carefully remove some segments and tape to make new ones. Two minute job, tops.

Good luck.
John.

Thanks for that one, John. I'll give it a try on my next roll and post the results.

[Aristophanes]

Originally Posted by Vics

Thanks for that one, John. I'll give it a try on my next roll and post the results.

I have used real (metal foil) duct tape instead of scraping, and electrician's tape. The former is conductive enough and can be read by the contacts.



I also used it to gap seal my ducts!

Much cleaner and quicker than scraping.

[Aristophanes]

Originally Posted by btgc

I'm afraid most P&S cameras, at least ones not prohibitively expensive, don't read intermediate ISO values and either revert to ISO100 or closest lower value.

That's a good point. I had one cheap camera that would only accept 25, 64, 100, 200, 400, and 800. If in doubt, stick to these.

I regularly upgrade Portra 400 to 800.



http://www.markushartel.com/blog/lea...-the-dx-sensor

[loquax ludens]

Originally Posted by Aristophanes

I regularly upgrade Portra 400 to 800.

I found a tech pub on the Kodak site for Portra 400, but not one for Portra 800. Here are some questions that occurred to me. If you happen to be able to answer any of these, Aristophanes, I'd love to know. Thanks!

Are the 400 and 800 films the same emulsion, or is it just that 400 pushes easily to 800?

How does 400 pushed to 800 compare to the 800 film at 800?

You can push the 800 to 1600. How well does the 400 push to 1600?

[Aristophanes]

Originally Posted by loquax ludens

I found a tech pub on the Kodak site for Portra 400, but not one for Portra 800. Here are some questions that occurred to me. If you happen to be able to answer any of these, Aristophanes, I'd love to know. Thanks!

Are the 400 and 800 films the same emulsion, or is it just that 400 pushes easily to 800?

How does 400 pushed to 800 compare to the 800 film at 800?

You can push the 800 to 1600. How well does the 400 push to 1600?

I don't know too much about Portra 800. I do know that the 400 is "new" and supposedly based on their Vision 3 emulsions from their motion picture film stock categories. The current Potra 800 speed is an older formula. I would not be surprised if Kodak discontinued it and advised shooting Portra 400 pushed.

I shoot the Portra at 320, 400, 640, 800, or 1600 in an SLR or RF and move it around if I feel the need depending on the max. aperture of my lens. For a P&S with fast enough shutter speed I mark it at 800. I have a Fuji Natura Classica that has a no-flash, fast lens system and DX-only coding which is why I started marking the rolls.

I do NOT push in processing. It is always processed at 400 (box speed). I doubt I will print much above 5x7, so not a major factor in speed/grain measure.

I started doing this because of the work of Jonathan Canlas. You be the judge:

http://canlasphotography.blogspot.ca...-beach-fl.html

There are lots of other samples and related discussions on Flickr:

http://www.flickr.com/groups/portra4...7627404027556/

For "beach" shooting or ISO 100 I revert to Ektar, a riotously fun film that I always shoot at 100. I have not shot the "new" Portra 160 (yet).