A rookie question about film speed
I have some experience with photography but a lot of what I know I learned a while back, and some of it I don't remember so well. Here's one thing I keep coming across that I don't quite understand.
I know about film speed, and grain, that kind of thing, but I'm not sure what someone means when they say they "push" film to a higher speed. For example, one guy talking about Ilford 3200 speed film says:
"The true speed of this film is around 1000-1600. I get much better results at these speeds but sometimes I have no choice but to shoot at 3200."
I don't understand that. How do you shoot a film at another speed? Is he saying he sets his light meter to 1600?
Thanks in advance.
In practical terms, "pushing" film is where you shoot it at a higher ISO than its box speed, effectively underexposing it, but then compensating for the underexposure by changing your development time. This comes at a price of more pronounced grain and higher contrast, but you can get images in darker conditions with faster shutter speeds than you otherwise could. Classic photojournalist's example is taking Tri-X, a 400 speed film, and shooting it at 1600.
Now, a film's "true" speed is getting deeper into things. ISO ratings are determined based on certain standards how the film behaves. From what I understand, films like Delta 3200 and Tmax 3200 aren't "true" 3200 speed films according to these standards, but rather slower ones that have been tailored in order to push well to 3200. So while the "true" speed of Delta 3200 is probably somewhere down around 1250, the box instructions assume you're going to push it to 3200 and the official development times are printed to match that.
Hope that helps.
Hmm, so if I shoot this Ilford 3200 film at 1600, I should develop for a normal time?
Try not to think of it in terms of normal or not normal.
If you want to shoot Delta 3200 at 1600, look for development times for it at 1600 with the developer you plan to use. That's really the important thing: match film, ISO, developer and the right development time. Whether or not the ISO you're working with is normal, push or pull is really secondary if your first goal is just to get negatives with good images on them.
You can get really detailed about what different films' "true" speeds are and this can shift depending on the developer and developing methods used as well, but if you're just starting into it I wouldn't worry about all of that. Just focus on what film you're using, what ISO you're shooting it at, and then get yourself some developer data that'll make it work.
Ah, so if I go to the Massive Dev Chart, it lists Delta 3200, but it gives different times. So if I shot the roll at 1600, I use the 1600 time.
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The Massive Dev Chart's word isn't law, but yes, that's what you're talking about, yes.
As you get further into this, then you might pay more mind to true speed, speed loss and speed gain in films and different dev combos. For my part, I've been doing my own B&W for about a year and I'm only just now starting to pay any mind to how different developers can offer speed gain.
I'm going to end up developing this in Ilford ID-11, just because I have like a half a gallon of it left and I don't feel like buying a different developer to do this film.
There was a thread about Delta 3200 a while ago. I think the general consensus (as much as you can ever get on Apug when it comes to certain films) was to shoot it at 1600 and use the development time, temperature and dilution specified for 3200 on the charts. That's what I do with D-76 and it should give you a starting point for your own experimentation.
All other things being equal, it's better to overexpose somewhat then to underexpose. If it isn't on the negative, nothing in the darkroom can make it so. This is why as a general rule I expose all my films + 1 stop if I can. Therefore, I set my hand held meter (incident reading) at half the box speed and cut back a little on development. This generally lowers contrast which is useful in the bright LA sun I shoot in.
I am going to develop mine in tap water because I have a whole sink of it.
Originally Posted by mrdarklight
Send your film away (use Kodak 100 color) and be done with it.
If ID 11 does what you want (It's not a pushing developer, it's a compensating one) fine, If it's what's under the sink, then you get what you get. Not how I develop my art. I suspect your chances for success are limited.
I don't mean to insult you, I just don't understand how you expect to learn anything from this.
tim in san jose
Where ever you are, there you be.