Film Data Sheets, How to Use

This will, I'm sure, show me as the beginner that I am. That's ok. The dumb question is the one you don't ask.

How do you use a Film Data Sheet?

I am not looking for what something is, but how do I use something in film exposure, developing, and printing; something being an element of a data sheet. I'm looking for practical application.

After googling and remaining unsatisfied, I ask here.

Thanks

Welcome to APUG

Start with the ISO number. Do you have a light meter? If so, we can discuss how to use it [not aiming up at the sky getting too much of the sky light reading], the light meter limitations and how to over come them.

If you do not have a light meter, the exposure for a sunny day is the aperture set at f/16 and the shutter speed is 1/[the ISO number].
The exposure for a partly cloudy day is the aperture set at f/11 and the shutter speed is 1/[the ISO number].
The exposure for a overcast day is the aperture set at f/8 and the shutter speed is 1/[the ISO number].

Film development is different story. Will you use a daylight load tank? With a daylight load tank and a changing bag, one does not need a darkroom to develop the film. Choose one film and one developer, take lots of photographs and develop many rolls of film until you really know what the one film and one developer can and cannot do. Once the film has been developed, do you have a darkroom available? If not, then you may send the film out for printing or scan the film. Scanning and digital handling are the purview of www.dpug.org.

Now ask your questions.

Each manufacture sheet is different and none are easy to read!
If you are starting you need a good book or mentor as well as datasheets
Critical things are fixing and washing
Try Ilfords getting started in monochrome site as well-

Ignore manufacturers' data sheets - you must only pay attention to what people on the internet (especially APUG) say you should do :devil:

pdeeh said:

Ignore manufacturers' data sheets - you must only pay attention to what people on the internet (especially APUG) say you should do :devil:

Click to expand...

Try
http://www.ilfordphoto.com/aboutus/page.asp?n=31

But the key formalism was H&Ds e.g.
https://www.nde-ed.org/EducationRes...adiography/TechCalibrations/Sensitometric.htm

but my photo book was published in '35 and misses out lots of the web 'techniques' which I still don't do, so Pdeeh's point is well made.

When you get happy with processing film and wet printing then there is/are whole worlds of alternative processes.

And you can still get film for a 16x20 inch 'plate' camera.

There is an exciton of salt prints in local gallery...

Noel

You can set the camera or exposure meter to half the ISO on the box or data sheet and note that the Fomapan data sheets show a different speed (i.e. ISO) from the ISO on the box.

box datasheet
100 125
200 125
400 250

this is Madison Avenue

The Foma film is cheap and grainy for speed but set the ISO to 100 or 200 is best for initial experiments.

Dont scan negatives and look at the screen - light box the negs instead, if the shadow (silver) is not there you need to expose more carefully, or you will have real trouble wet printing. Or scan as transparencies, the shadows are critical to your prints, you cannot print clear film...

Dont worry about developer choice, you can use coffee if you want _ no detectable difference, you do need to fix and wash carefully.

Kodak do cheap hypo clear.

Xmas said:

There is an exciton of salt prints in local gallery...

Noel

Click to expand...

I do like the idea of Tate Britain being a local gallery

pdeeh said:

I do like the idea of Tate Britain being a local gallery

Click to expand...

Access is easy for me as I have a free coach to London Victoria, with the only handicap that I need to walk past Mr Cad's and Gray's, on way, from Victoria to Tate. Most week ends I'm in London anyway.

(they are both analogue photo shops - for 'USA cousins' and others, and difficult to walk past).

Yah, I know. If it's on the 'net it's gotta be true.

Well, there sure are a lot of experts to choose from on the web, meaning people who are experts at never reading the tech sheets! But what
do I know, because I do need them and read them.

DREW WILEY said:

Well, there sure are a lot of experts to choose from on the web, meaning people who are experts at never reading the tech sheets! But what
do I know, because I do need them and read them.

Click to expand...

I read them too. And shoot film at box speed.

Well, since no one else answered your question, I'll take a shot at it. In a nutshell, it's what the manufacturer believes leads to optimal results using what they believe is proper technique. But their idea of optimal results may not match what you want and their idea of proper technique may not match your technique. Further, since so many experienced photographers regularly expose film at significantly less than box speed, there may be other factors that influence the manufacturer's data.

So I suggest you first, establish your own technique for exposure and processing, making sure it's repeatable. Start at box speed and manufacturer's recommendations with a single film and developer. Adjust to get the results YOU want. Best to change one thing at a time (i.e. don't change you exposure index and development time concurrently).

If you read enough forum posts, you'll generally find a few people whose suggestions you value. Just be aware of those who seem to fall prey to the old saying: "often wrong, but never in doubt".

Of course manufacturers know absolutely nothing about the products they manufacture. It's like the moon landing hoax. All those
chemistry phD's Kodak has allegedly employed for decades never really existed; therefore Tech Sheets likewise merely perpetuate mythology. No truth existed until web forums popped up and all opinions suddenly became equal.

DREW WILEY said:

Of course manufacturers know absolutely nothing about the products they manufacture. It's like the moon landing hoax. All those
chemistry phD's Kodak has allegedly employed for decades never really existed; therefore Tech Sheets likewise merely perpetuate mythology. No truth existed until web forums popped up and all opinions suddenly became equal.

Click to expand...

Drew you forgot [sarcasm][/sarcasm] tags.

aurum earring said:

This will, I'm sure, show me as the beginner that I am. That's ok. The dumb question is the one you don't ask.

How do you use a Film Data Sheet?

Click to expand...

You take a look at how far the film can be pushed or pulled with your developer of choice, according to the suggestions on the datasheets. You will find, for example, that the manufacturer disrecommends some developer for certain applications like push processing.

Sometimes, like in Foma sheets, there will be curves that tell you how strongly contrast change versus development time/temperature, for each developer. Thus, you will see that for some developers you need extra care in development and temperature if you want to have a consistent contrast result. And viceversa.

You will find time versus temperature adjustment curves, so you will be able to compensate development times for using the temperature of choice.

You will see the spectral sensitivity curves and with this you can see if the film has some weird funny response, for example you can immediately see that Fomapan 400 has an extended spectral sensitivity to red, then you know you can exploit that.

If you will do long expoures, the reciprocity compensation curves to use will be there.

You will also see what is the agitation procedure and frequency that the manufacturer recommends.

Sometimes, also, for example in ILFORD datasheets -which are very very nicely laid out-, you will see the recommendation which developer to use according the preference. Something like, "for finest grain with a speed loss of 1 stop, use Ilford Perceptol", "for maximum speed, use Ilford Microphen", "for best overall image quality, use Ilford ID-11". This can give you a starting point.