Film speed testing

[macandal]

Okay, I'm trying to do a film speed testing, but the two sources I have, do it in increments/decreases of 1/2 or 1/3 stops. Now, I'm a newbie. 1/2 and 1/3 stops may not be complicated to you more experienced fellows, but they are to me, a beginner soul. Can someone please give me the easy version of the film speed test? In whole stops? None of this half or third business? These are my requirements:

I'm testing my large format Sinar F2 (obviously sheet film)
I have access to a densitometer
I have a gray card (I know there are ways of doing this test without one, but I want to do it with a card)

I think that's it. I can't think of anything else. Can someone give me the easy version of the film speed test? Thanks.

[SpeedGraphicMan]

Give this a read through...

http://www.earthscenics.com/manuals/zoneman_8_11_05.pdf

[Bill, 70's military B&W]

Re: Film speed testing
Give this a read through...

http://www.earthscenics.com/manuals/zoneman_8_11_05.pdf

I'm just getting started in LF myself, and am about ready to start doing some testing on my own, hopefully this weekend. I have several lenses and cameras.

I read the above and I wonder if it means that you would have to do the calibration for each camera/lens combination you have??? A different ISO for this camera with that lens...etc?
Or does the camera have very much to do with it? All my lenses are attached to shutters, so would I have to do this test for ISO determination just for each lens?

That is very complicated, how does everyone else handle having more than 1 lens and used on more than 1 camera? I have a speed chart for each lens I have and I keep it with me, I trust the aperture settings.

Thanks, Bill

[macandal]

Re: Film speed testing
Give this a read through...

http://www.earthscenics.com/manuals/zoneman_8_11_05.pdf

I'm just getting started in LF myself, and am about ready to start doing some testing on my own, hopefully this weekend. I have several lenses and cameras.

I read the above and I wonder if it means that you would have to do the calibration for each camera/lens combination you have??? A different ISO for this camera with that lens...etc?
Or does the camera have very much to do with it? All my lenses are attached to shutters, so would I have to do this test for ISO determination just for each lens?

That is very complicated, how does everyone else handle having more than 1 lens and used on more than 1 camera? I have a speed chart for each lens I have and I keep it with me, I trust the aperture settings.

Thanks, Bill

I'm afraid your worst fears are about to materialize. My understanding is that the combination camera, lens, film is what determines the appropriate film speed. So, depending on how many lenses you use on a given camera, and hoping--for your sake--that you only use one kind of film, that's how many combinations you have of film speed. So, one camera, three lenses, and assuming just one kind of film, will have up to three different results.

Luckily for me, for my 4x5, I only have one lens and one kind of film I use. So my testing becomes very easy.

[Chuck P.]

I'm afraid your worst fears are about to materialize. My understanding is that the combination camera, lens, film is what determines the appropriate film speed. So, depending on how many lenses you use on a given camera, and hoping--for your sake--that you only use one kind of film, that's how many combinations you have of film speed. So, one camera, three lenses, and assuming just one kind of film, will have up to three different results.

Luckily for me, for my 4x5, I only have one lens and one kind of film I use. So my testing becomes very easy.

If one believes that this guy knew what he was talking about, one would know that he abslolutley did not recommend what you are suggesting here to the OP.

[Doremus Scudder]

Okay, I'm trying to do a film speed testing, ... Can someone give me the easy version of the film speed test? Thanks.

I think we are making things a bit too difficult here. The OP is a beginner and wanted to find a personal film speed. He is daunted by working in fractions of a stop.

Plus, finding a personal E.I. that you can use and get good results from is not all that difficult. Sure, there is a whole lot of science and lots of variables in lenses, cameras, flare, etc. that we can figure in, but I never worried about that when I was starting out.

I recommend to the OP to do a simple test with his grey card, the camera and lens he uses most often and the film he wants to test. This assumes a fairly modern, correctly working shutter. Testing it would be nice, but if 1 second and 1/2 second sound good, that should be fine.

Set the film speed on the meter to half of the box speed of the film (one stop overexposure; e.g., if you are testing 400 speed film, set the meter to 200). Meter the card and place it in Zone 1. Pull the darkslide halfway and shoot (use a slow shutter speed, they are more accurate). Do the same a 1/3 stop slower than box speed (i.e., the next film speed slower than box speed, for 400 speed film that would be 320).

Develop these negatives and read them with the densitometer. Find the Zone I density that is the closest to 0.01 above FB+F without being under that value. Use that for starters. If it looks like the intermediate speed (the one that wasn't tested) is better, e.g., if the 1/3-stop under was just a bit under 0.01 above FB+F, and the one-stop over neg is way over, then use that instead.

Or, you can ditch the densitometer completely and make proper proofs. Find minimum time for maximum black on your printing paper for the clear area of the neg. Print your negs at that time and lighting. Find the strip that just starts to show grey. That's your Zone I and your film speed.

Then do a test for N development and expansions and contractions if you like and go out and shoot. Make adjustments to your system based on your shooting in the field.

That's more than enough to get started and get good results.

Best,

Doremus

[Bill Burk]

I think we are making things a bit too difficult here. The OP is a beginner and wanted to find a personal film speed.

Doremus,

You gave the simplest film test idea, and I endorse it.

As to the other answers being too difficult, sure I went off the deep end. But I believe OP is about to embark on a journey searching for a deeper understanding (so he can soak in the gritty details)... He's asked for books... This is the kind of hunger for knowledge that gets accelerated faster than any learning in schools can deliver (I think I just read an Edward Abbey passage to that effect).

I would say the high level view is... For black and white it's all about "expose for the shadows, develop for the highlights". For color (OP has indicated interest in color), since there are three layers of carefully balanced film, you cannot control contrast by development because it will throw off the balance, so the film gets developed "a standard amount."

I don't know color that well so correct me if I'm wrong: Color balance can be compensated easily with filters. Contrast control is done with masking if necessary. If possible... deal with contrast in advance by altering the light ratio when shooting.

[Brian Ellis]

I think we are making things a bit too difficult here. The OP is a beginner and wanted to find a personal film speed. He is daunted by working in fractions of a stop. . . .

I agree that some of the answers here go way beyond anything he's likely to understand. But while he asked about ways to find a personal film speed, he also asked some specific questions that indicated some confusion on his part, to wit:

"I read the above and I wonder if it means that you would have to do the calibration for each camera/lens combination you have??? A different ISO for this camera with that lens...etc?
Or does the camera have very much to do with it? All my lenses are attached to shutters, so would I have to do this test for ISO determination just for each lens?"

[macandal]

I agree that some of the answers here go way beyond anything he's likely to understand. But while he asked about ways to find a personal film speed, he also asked some specific questions that indicated some confusion on his part, to wit:

"I read the above and I wonder if it means that you would have to do the calibration for each camera/lens combination you have??? A different ISO for this camera with that lens...etc?
Or does the camera have very much to do with it? All my lenses are attached to shutters, so would I have to do this test for ISO determination just for each lens?"

Brian, that wasn't me. I, macandal or Mario, am the OP. That question was asked by someone else reading this thread.

[Brian Ellis]

Brian, that wasn't me. I, macandal or Mario, am the OP. That question was asked by someone else reading this thread.

Oh, O.K., thanks. I didn't notice that. Hopefully I helped him if not you.