Is it true (ISO 100 vs 400)?

[SolaresLarrave]

Is it true that slow film is contrastier than fast film? I used ISO 400 film for the longest time and thought I was getting decent images (though not contrasty enough for my taste), and then, just for the heck of it, I switched to ISO 100 film and then, there it was... images with more contrast than in the past! 🙂

So, is that true? Independent from developing, is it true?

For examples of this, take a peek at the latest entry in my Leica M4-2 blog.

Thanks in advance!

 

[Mudman]

I've usually found that higher iso film has less dynamic range, thus is more contrasty. Low ISO film has always appealed to me for it's grain structure and overall better clarity in the images that it produces.

 

[Rob-F]

Yes, it seems to me that there is something to this, even independent of development. Of course, we can alter contrast by the choice of developer and developing time; but I have known certain slow films to be more contrasty than faster ones. The most striking example, I think, was with Panatomic-X (no longer available). It was contrastier than Plus-X and Tri-X. Also, it seems to me that HP5, a 400-speed film, is lower in contrast than most others. In theory, if you develop a given film to a given gamma, or contrast level, they should have the same contrast. But notwithstanding this, I think some films are just intrinsically snappier than others.

 

[Fotohuis]

Yes, that is correct. So the decision to take a slower type film when you have too much harsh light is wrong. Just take an iso 400 film plus a ND 0,6 filter. iso 25 film even has a lot of contrast and is difficult to tame even in a low contrast type developer.
Apart from the contrast a slow film has more resolution, lp/mm. In general an iso 400 B&W film about 90lp/mm, an iso 100 film 140lp/mm and an iso 25 film 170lp/mm.
A color film (C-41 or E-6) has even less resolution then an iso 400 B&W film.

 

[charjohncarter]

Plus-X to me was contrasty, more so than TriX. But Tmax 100 seems to have more tones and much more dynamic range.

You say 'independent of development,' I find development scheme (time, dilution, agitation) very important to contrast and dynamic range.

 

[mdarnton]

Looking at the photos in your blog, what I see is that your EI400 photos quite often suffer from lack of exposure, not lack of contrast. When you don't have a lot in the shadows, you're OK, but with pictures that are mainly shadow, there's nothing there. To me, this means a metering problem. There aren't any similar type of shadow-dependent shots in the EI100 batch, so this problem may eventually show up there, too, when you try that kind of photo.

The apparent low contrast comes from printing the dark areas too light, to try to draw out shadow detail that obviously is just not there. More exposure would fill in detail in the shadows better, and then you could print a real black and still have something in the shadows. I see some of this tendency in the other shots, but because there's nothing important in the deep shadows, you aren't noticing a problem. Based on what I can see, many of the shots on your blog are from what I would regard as unprintably underexposed negs, not a contrast problem.

 

[mfogiel]

Unless you wet print, high contrast negative is not all that desirable. Yes, it is easier to get high contrast with slower films, because typically their DR is smaller, so even with a slightly longer development the contrast increases fast.
Overall, the contrast ( steepness of the density curve) depends on development time and agitation. Take your preferred films, expose them every 6 shots as follows: -2 stops, -1 stop, box speed, +1 stop, +2 stops, +3 stops. Then cut the film into 3 pieces and develop them as follows: recommended time (for box speed), 50% shorter, twice as long.
Then look up the results and see what you like best.

 

[Ko.Fe.]

The only film I found to be contrasty so far is Pan F Plus at the box speed.
But contrast is achvable with any film. By filters on the lens, PP on computer or contrast filter for RC paper. Modern lenses will give load of contrast as well. One of my enlarger lens seems to be very contrasty as well...

 

[SolaresLarrave]

Thanks a lot... and especially thanks to mdarnton, who seems to have nailed the problem! 🙂 It may be that the difference I perceived was not so much contrast but metering and exposure. Still, after using ISO 400 film for a long time, one month of using ISO 100 gave me results that I like a lot better. I guess it's time for me to switch...

Now, I haven't developed any ISO 100 film at home yet, and, since I use T-Max here, I still have to see how it turns out with my Arista Edu ISO 100. In any event, thanks for your input! 🙂

 

[SolaresLarrave]

Before I forget... I was probably comparing apples and oranges. Most of my work in ISO 400 was done in chromogenic film, which, as I learned later, does not react to filters (yellow and the like), whereas the photographs in ISO 100 were done with real B&W film and a yellow filter on the lens. Maybe that explains the difference... in addition to the exposure factor.

 

[Ko.Fe.]

So, you were using some weird 400 film, switched to normal 100 film, took it with contrast increasing filter and get more contrast. What a "surprise". 🙂

 

[SolaresLarrave]

Not weird film... Just chromogenic. However, I have used Arista II and HP5 and found them not as contrasty as my images in Arista 100, so, it was a bit of a surprise still.

 

[Godfrey]

Before I forget... I was probably comparing apples and oranges. Most of my work in ISO 400 was done in chromogenic film, which, as I learned later, does not react to filters (yellow and the like), whereas the photographs in ISO 100 were done with real B&W film and a yellow filter on the lens. Maybe that explains the difference... in addition to the exposure factor.

That's incorrect, although each film has its spectral sensitivity shape and films like XP2 Super have a different spectral sensitivity shape from TX and the like.

G

 

[Drago]

I don't think that's true. It has to do with the developer/film combo, but mainly developer to my eyes. I'v been using Rodinal ever since i start developing, but recently bought a bottle of HC-110, just to try something new. WEll, at least to my eyes negs developed with Hc-110 have a lot more contrast than those with Rodinal, which is a lot more forgiving. Let a film 1 min more with Rodinal and you'll still have a usable pic. Do this with HC-110 and you may end up with contrast which is too high

 

[Fotohuis]

Any chromogenic film tends to a lower contrast. And much is depending of a good C-41 development. For XP2 super the best exposure is around iso 200-250 and a normal C-41 development.
You can not compare these type of films with any regular Silver based B&W film.
About HC-110: It is a fast working type developer. You have to make a carefull choice of the type dilution and film. HC-110 works very good with e.g. the new Foma Retropan 320 Soft because it is a really low contrast type film.