# Film Speed Question - Photography

Hi, As I've repeatedly said on all my posts so far... I'm completely new to 'proper' photography (ie NOT point and click), so I have a question that seems to be based on a childhood misconception (I'm 29 now, to put the 'child' in perspective)... When I was a kid, I used to buy '100' speed films, or if I was really feeling posh and rich, a 200. I never really understood about all this, I just bought what there was. I always presumed that the bigger the number, the better quality film, but now, from reading various posts/articles, I ...

1. ## Film Speed Question

Hi,

As I've repeatedly said on all my posts so far... I'm completely new to
'proper' photography (ie NOT point and click), so I have a question that
seems to be based on a childhood misconception (I'm 29 now, to put the
'child' in perspective)...

When I was a kid, I used to buy '100' speed films, or if I was really
feeling posh and rich, a 200. I never really understood about all this, I
just bought what there was.

I always presumed that the bigger the number, the better quality film, but
now, from reading various posts/articles, I get the impression I'm wrong.

Can someone please enlighten me as to what all this 100, 200, 400 etc thingy

Many thanks,

Jon

Akomic Guest

2. ## Re: Film Speed Question

On Tue, 28 Oct 2003 10:12:26 -0000, "Akomic" <ic> wrote:

The ISO number is the film's speed. Double the number, double the
speed. The higher the number the quicker the film reacts to light.

In simple terms this means that if your camera's meter says that f/11
is the proper exposure for 100 speed film, then f/16 would be the
f/stop for 200 speed film, since the 200 speed film is faster, it
needs less light and therefore a smaller f/stop. (Since you asked the
question, I guess I should as whether you realize that f/16 is smaller
than f/11).

the speed the less quality the film (because the grain tends to get
larger).

-- JC
J Guest

3. ## Re: Film Speed Question

Ok, it's fairly simple: (ok well maybe not)

The speed rating is a standard method of calculating how fast the
silver-halide (the substance that makes film turn different colors) reacts
to light.

The higher the film speed the quicker it will react to light.

lets say for brevity that you have a 100 speed film in your camera, and
your light meter calculates that you need a one-second exposure.

put in a 200 speed film you cut the exposure time to one-half-second

400 speed one-quarter second etc.

now here's the catch -- in most films, the higher the speed rating or
ISO/ASA the grainier the film gets.

for instance KODAK tri-x 400 in my opinion is almost unuseable for
enlargements over 8x10. whereas the Kodak 125 or Ilford FP4 100 can go
to11x14 easily. (this is entirely subjective)

depending on the type of photography you are doing, the higher iso films may
be an advantage (sports, low light situations, babies etc...)

for most of my work I stick with either "Kodak Portra VC 100" or "Kodak
Ektachrome RS 64" and in B&W I use Kodak 125px or Ilford FP4 Pan-F 25 iso

for starters stick with 400 speed film if you are not doing the enlarging
yourself. otherwise, when you want control in the darkroom, pickup a pack of
"Ilford multigrade RC Variable contrast Paper" and a pack of filters and use
the Kodak 125px Film. you will get stunning results.

(grainy) and four rolls of Kodak 125 PX, (Both Black and White) and learn
everything about your camera, then stick to one type of film for a while, it
will ensure that you have a consistent set of results, and you will learn
as having less frustration when your camera does something unexpected.

to sum it up, when you are shooting objects in low light or high speed
action, use the higher ISO films. When you need the best possible quality
however the lower the iso the better.

Stay away from Kodak Max, go to a photography hobby place to find your film,
maybe even call ilford UK to find a dealer.

"Akomic" <ic> wrote in message
news:bnlfe3\$7jr\$svr.pol.co.uk...
thingy

4. ## Re: Film Speed Question

Akomic wrote:

These numbers tell you something about the "speed" of a film.
Low numbers are slow films, high numbers ar fast films.

With higher numbers in film speed (ASA) you need less light to get about
the same result. A film with ASA 200 is two times faster than a film
with ASA 100, ASA 400 two times faster than ASA 200 and so on.
Alas, the speed of a film is paid with quality. Highspeed films are
usually more grainy, show less vivid colors (i.e. if they are
color-films, not b/w ;-)) and tend to have a lower resolution (the
ability to show fine and finest details). On the other side, using fast
films you can take a shootwith less ambient light at the same shutter
speed and f-stop as compared to a slow film.

HTH

Matthias
--
matthias.ruckenbauer(AT)aon.at
I'm sorry for the inconveniences.
Thank you!

spameater.mr Guest

5. ## Re: Film Speed Question

On Tue, 28 Oct 2003 10:12:26 -0000, "Akomic" <ic> wrote:

The larger the number the "faster" the film (or in laymans terms, you
don't need as much light to achieve the same exposure as with a
"slower" film)...

If you are talking about true QUALITY, then you have it backwards.
The lower the number, the finer the grain in the film, and therefore
the sharper the image will be...however, it requires more light to hit
the film than the higher speed films.

As a general rule of thumb, in bright light or when shooting
stationary subjects, lower speed films are used. When shooting in
dimmer lighting situations, or with subjects that are in motion or
otherwise exhibiting action, you would choose the higher speed films.

As with anything else, there are always exceptions to the rule, but
the rule applies most of the time, and for most people's general
photographic usage.

Think of it like this.

A Chevrolet Corvette with a big block 350 would be like a "faster"
(higher numbered) film. It's a lot faster, and doesn't take as much
gas to move, but only carries a few passengers.

A Bluebird Schoolbus is like a "slower" film (lower numbered). It may
not have the speed of the Corvette, but it can carry over 10 times as
many passengers (or in this case "pixels").

6. ## Re: Film Speed Question

Akomic wrote:

The slower film, like 100, needs more light to be properly exposed. It
also has finer grain.

The faster film, like 1600, needs less light for proper exposure but the

Confused? Go to: http://www.photo.net/making-photographs/film
for a good explanation.

Bob

Bob Guest

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•