SilberSalz (ECN-2) film - 1 stop overexposure recommended - why?

[Colin O]

I'm considering various colour negative film options and one option that looks interesting is SilberSalz film - it is Kodak Vision3 film, loaded into 135 cassettes. The remjet layer has not been removed from the film (unlike Cinestill varieties) and so there's no halation effect (which is a plus point in my opinion). The film consequently needs to go through the ECN-2 development process.

One thing I'm curious about though is that the DX code on the cassettes is set to be 1 stop slower than the actual ISO rating of the film. So, for example, if you buy SilberSalz 250D, the DX code indicates 125 to the camera. SilberSalz says on their website, "we recommend overexposing SILBERSALZ35 films by one stop for quality reasons."

What are these "quality reasons"? The ISO rating is surely a standard measurement of the sensitivity of the film. Why not just expose at the actual ISO rating of the film?

[AJG]

When I shot color neg films professionally I routinely overexposed by 1/2 stop or more because I found that I got better prints that way.  Given that many older cameras with CdS cell metering tend to underexpose as they age it makes sense to me to tell the camera to overexpose routinely.  I once managed to forget that I had set a Vivitar 285 to full power manual shooting a wedding and took several frames that way and probably over exposed by 3-4 stops until I realized that the recycling time was way too long for fresh batteries. The machine prints from those negatives were fine.  The lesson I took from that was that color neg could take a lot of over exposure before the results would be unusable.  Under exposure, on the other hand, quickly leads to smoky green shadows and generally poor print quality. You are right that the ISO should be what the manufacturer rates it to be, but for color neg some over exposure is often helpful, and is easily compensated for in printing. 

[iosif_astrukov]

First I want to say that silbersalz35 are great! I tested their service in 2021 - I wanted to try the bleach by pass option. They offer amazing quality and service, probably their scans are the cleanest I ever have seen. The presets they are adding are... I don't know, I didn't like it, but as long as they are giving the raw files too, it's what you prefer. I highly recommend them, but a bit expensive for me outside Germany (the shipping costs are twice the other ones)

I also asked myself why they recommend overexposing, my explanation is that the movie films are extremely high dynamic ones, much more than the photo films, and I guess in a matter of one stop you won't even notice any difference. It also depends a lot how it is developed, it's possible that they have optimised the lab that way.

[Colin O]

Thanks both for the helpful and reassuring answers.

[Alan Marcus]

Color films are tweaked based on how the displayed image will be produced. Amateur films are made more contrasty because the camera is likely to be equipped with a substandard lens and because there will likely be a long delay between exposure and processing / printing. Professional films are fabricated with less contrast because this generates a longer tonal scale. Cine negative films are an intermediate step in the making of positive release prints for the theater. Movie projectors systems use high-quality lenses, and the image will be shown in a darkened room. Thus, the cine negative film has lowered contrast. If these films are to be used in a still camera developed and printed by printers with a diffused light source, exposure modification will make a better match film–to-final-output method.   

[Colin O]

Thanks Alan.

Just a quick follow-up - I had contacted SilberSalz themselves before posting here, and I got a short reply from them...

Quote

 

Overexposed film gets best colors, more detail in the shadows without the risk of clipping the highlights.

Best regards,

Enzo

 

 

[glen_h]

Usual C41, and I suspect ECN2, films have a Gamma of about 0.5.

(That is most obvious when choosing color correction filters.  The effect of a filter is twice the filter number.)

 

When using manual exposure cameras, I round to the next whole f/stop.

The low Gamma gives them a very large exposure latitude.

Unlike usual black and white films, though, you really want an enlarger light meter.

(Or just scan them.  Hopefully with a scanner that adjusts for exposure.)

 

For color negative pictures of family and vacations, I always used Vericolor III.

That is, as noted above, lower contrast than Kodacolor. 

 

I did once develop 5247 (Seattle Film Works days) in C-41 chemistry.

All you need to do is rub off the rem-jet in the rinse. 

(That is, for hand developed.  Not so good for machine developing.)