What does "TriX pushed to 1600" mean?

[CopperB]

In my goal to learn about shooting film, I repeatedly see references to 400 film in a camera being 'pushed' to a higher ISO on film forums. What does the term refer to? Setting your light meter to 1600 film to come up with recommended settings while shooting 400 in your camera? Developing it as if it was 1600 film? How exactly do you push film?

Thanks for indulging a newbie's question.

 

[Roger Hicks]

'Pushing'= 'increasing development time in order to get more detail in the dark (shadow) areas, at the expense of getting more contrast'.

True ISO speeds depend on certain criteria of exposure and development: see http://www.rogerandfrances.com/subscription/ps iso speeds.html and associated modules.

True ISO speeds vary with the developer: see http://www.rogerandfrances.com/subscription/ps neg development 1.html, where you will also find more about pushing.

Cheers,

R.

 

[not_in_good_order]

Without getting too technical, I would explain it as telling your camera that you are using 1600 speed film and then using different development times to extract as much detail out of what is essentially underexposed film. Please read the push processing section (starts on page 6) of Kodak's Tri-X technical publication:

http://www.kodak.com/global/en/professional/support/techPubs/f4017/f4017.pdf

 

[Ronald M]

It means it was underexposed two stops and overdeveloped to try to recover lost shadow detail which doesn`t happen and to try to gain some density in the highlights so #6 paper is not required.

You end up with poor prints and no shadow detail, just black blobs.

Now there will 40 people who will swear it works fine. There are also people who think government is the answer and there is nothing anyone can say to point out facts and change their minds. Religion is the same.

So I don`t discuss religion, politics, or pushing film except to say try it and see if you like it.

A few developers will get a bit more shadow density like Microfin or Diafine or ACufine.
2 stops is even optimistic with them. Diafine is currently popular. Acufine was in 1966 when I started. Tri X and Acufine EI 640 was the PJ formula.

So let the arguments begin.

Just remember, exposure controls the shadows, development controls the highlights, Always was, always will be.

 

[matt352]

Pushing film means to expose and develop the film at a higher EI than it is rated for. By developing the film for a longer period of time, more of the film emulsion is "eaten away" to compensate for the small amount of light the exposure was made with.

The consequences for pushing film are that the grain in the images becomes more noticeable and the exposure tends to show more extremes of white and black, ie. the 'in between' grey tone spectrum is shortened.

Check out flikr searching Tri-X and 400, 800, 1600, 3200, 6400, 12800 and comparing.

Also, if you are really keen to learn film, you could likely find some very useful resource books at your local used book store. Yes they're old, but chances are they're 20+ years newer than your M3.

 

[CopperB]

Thanks for the explanation.

 

[pevelg]

Pushing'= 'increasing development time in order to get more detail in the dark (shadow) areas, at the expense of getting more contrast'.

You end up with poor prints and no shadow detail, just black blobs.

The consequences for pushing film are that the grain in the images becomes more noticeable and the exposure tends to show more extremes of white and black, ie. the 'in between' grey tone spectrum is shortened.

I guess this explains why I was so disappointed with Neopan 400 pushed to 1600. I was very much surprised by how dark the shadows where and how overblown the highlights, with little mid tones. Still had some really great photos, and had I not pushed the film, I wouldn't have any shots at all.....

Neopan 400 pushed to 1600, Mamiya 7, 80mm lens, shot at F4, speed 1/30(?)

 

[dbookbinder]

There were even post-development intensifiers that would increase negative density after the pushed film was developed, or if it was developed normally but turned out to be underexposed. Chromium intensifier is the one I remember using 30+ years ago. I managed to save a few important shots with it, though of course they had a very high-contrast, high-grain look.

 

[Melvin]

It gets tricky. Under street lamps I shoot 400 speed film at 400 with f1.4. So this should be the same as shooting a f2.8 lens with 1600 speed film, right? Two stops difference in lens speed, two stops difference in film speed. But the 1600 speed film comes out underexposed, with no shadow detail. It is an example of reciprocity failure. On the other hand if you have decent, even light, like pevelg's photo above, it works fine.

 

[maddoc]

Problem is .... there is no "real" 1600ISO film. 1600PR and P3200TMZ are ~ 1000ISO at best. Exposing these films at box-speed is already pushing them but with lesser loss in tones than pushing a 400ISO film to 1600.

I have always found that I get better results (tones) when using a 400ISO rated film at night (with fast lenses) compared to a 1600ISO rated film with slower lenses.

 

[mackigator]

It means its too dark for the soccer moms to get usable photos of their kids on stage.

 

[maddoc]

Off topic .... I quite often come across the expression "soccer mums". What does that stand for ? Just curious ....

 

[mackigator]

http://en.wikipedia.org/wiki/Soccer_moms

 

[Al Kaplan]

Before the dangers of mercury were recognized we use Victor's Mercury Intensifier to salvage underexposed negatives. Another thing that works is Kodak Rapid Selenium Toner.

About the only thing thats changed in the past half century is that ALL films have become less grainy. Whether the current Delta 3200 or Kodak Royal-X Pan Recording circa 1962 you could get a "useable" (but not great) negative by overdeveloping a bit to 3200.

"Soccor Mum" (or Mom) refers to an upper middle class housewife. Hubby makes enough to support the family, Mum used to drive a minivan and now has an SUV, picks the kids up from school, takes them for piano lessons, drives them to soccor practice, etc.

 

[maddoc]

Thanks for the explanation, guys ! 🙂