This is a handout that I came up with for one of my photography classes I teach (Page 3): Excellent suggestion.

grandpaw

Abo wrote:

For a student, the table you have created is an excellent learning tool IMHO.

The (pedantic?) issue with ISO, not actually letting in more light, could
be addressed by adding a foot note, explaining that the ISO
amplifies the signal (by said factor), rather than actually
adjusting the amount of light.

Good work Sir.

Excellent suggestion.

rmalarz Loc: Tempe, Arizona

However, your explanation of ISO covers only digital. This statement completely ignores ISO as related to film. It would be far better to simply state ISO relates to sensitivity, regardless of the method used to increase sensitivity, that being electrical gain or grain structure.
--Bob

Abo wrote:

For a student, the table you have created is an excellent learning tool IMHO.

The (pedantic?) issue with ISO, not actually letting in more light, could
be addressed by adding a foot note, explaining that the ISO
amplifies the signal (by said factor), rather than actually
adjusting the amount of light.

Good work Sir.

lamiaceae Loc: San Luis Obispo County, CA

rmalarz wrote:

The bottom statement is misleading. The aperture and shutter speed are the factors that affect the amount of light entering the camera. ISO is not related to that.
--Bob

Exactly.

StanMac Loc: Tennessee

grandpaw wrote:

You are technically correct that ISO doesn't change the amount of light coming into the camera but it will amplify the amount of light or cut the amplification in half that is produced by the aperture and or shutter speed by moving to the left or right.

I would treat ISO as a separate parameter from shutter and aperture since, for any given scenario, it’s setting will drive the other two settings for the optimum exposure. The arrangement of the blocks in the diagram imply that ISO is the base upon which an exposure is built. Think of it in terms of the old film days, where we didn’t have the option to change our ISO from frame to frame.

Stan

Hip Coyote

I think some people are missing the point...this is for the entry into photography....not some long discussion of gain or loss of sensor sensitivity...its like a bunch of gun nerds sitting around talking about ballistics when a student is just trying to learn the basics of handling a firearm...its off putting and not instructive. Is the chart completely accurate on ISO? Probably not. Does it provide a good understanding of the basics of how the triangle works? I think so. As a student gains more knowledge, he/she can take the ISO for what it is. IMO, the chart is instructive and effective for what the OP is trying to accomplish.

Mark Sturtevant Loc: Grand Blanc, MI

Some edits may be considered, but this is still very useful.

rmalarz Loc: Tempe, Arizona

Your "probably not" pretty much sums up the issue. If one wants a substantial foundation upon which to build, small flaws can definitely affect the sturdiness of the structure. Why not simply provide that substantial and correct foundation from the start.
--Bob

Hip Coyote wrote:

I think some people are missing the point...this i... (show quote)

Rab-Eye Loc: Indiana

Hip Coyote wrote:

I like it a lot. The iso thing is tricky because it has to do with sensor sensitivity. Maybe “light coming into or recorded by camera?” Not sure exactly. It your does makes sense to me.

My understanding of ISO in digital cameras is that it is gain applied to the image, not that it makes your sensor more or less sensitive to light. I could be wrong.

StanMac Loc: Tennessee

rmalarz wrote:

For photographic exposure, yes, you are correct. When I teach intro to photograpy, I use a balance scale where the weight upon one side is ISO and weights representing aperture and shutter speed are placed on the other side.
--Bob

Excellent example of the relationship of those exposure parameters.

Stan

anotherview Loc: California

Right. A change in the ISO setting involves a change in the amplification of the native signal of the camera sensor.

The sensitivity of the camera sensor itself does not change.

rmalarz wrote:

The bottom statement is misleading. The aperture and shutter speed are the factors that affect the amount of light entering the camera. ISO is not related to that.
--Bob

JVada Loc: OH

grandpaw wrote:

I have posted this before but it may help a lot of new photographers understand their camera settings.

Nice comparison re the chart. Another relationship might the exposure “triangle” whereas a simple, graphic triangle is depicted and at each point either put ISO, APERTURE(f/stop), and then finally SHUTTER SPD(SS). The order does NOT matter and label no more, no less. It expresses the fact that one point of the triangle will invariably affect the other two(or…just one of the other triangle points…). So, eg., ISO affects both f/stop & SS(unless the photographer elects to just change one of those two opposite points to fully remedy the change…).

HOHIMER

rmalarz wrote:

The bottom statement is misleading. The aperture and shutter speed are the factors that affect the amount of light entering the camera. ISO is not related to that.
--Bob

How about this:
Moving one step to the left on any of these three settings will double the amount of light detected by your camera.
One step to the right on any of these three settings will cut the light detected by your camera by half.

rmalarz Loc: Tempe, Arizona

ISO also refers to film. We certainly need to include that aspect in the discussion.
--Bob

anotherview wrote:

Right. A change in the ISO setting involves a change in the amplification of the native signal of the camera sensor.

The sensitivity of the camera sensor itself does not change.

rmalarz Loc: Tempe, Arizona

How about this:
Exposure is determined by the amount of light passing through the aperture combined with the duration of time that light is allowed to pass through.

Photographic exposure involves that light striking a photosensitive material. The sensitivity is indicated by the ISO (formally ASA). The larger the ISO value the more reaction that material has to the light striking it.
--Bob

HOHIMER wrote:

How about this:
Moving one step to the left on any of these three settings will double the amount of light detected by your camera.
One step to the right on any of these three settings will cut the light detected by your camera by half.

1grumpybear

grandpaw wrote:

I have posted this before but it may help a lot of new photographers understand their camera settings.

Jeff a very good graph to help explain there functions. I took your graph and fliped the shutter speed to demo how the three interrated. For a given light and aperture if changed the shutter speed you needed to change the ISO. Several years ago when I was more involved in helping newbees out I built a physcial demo of how they interelated. It had three vertical rods. Each rod represented ISO, Shutter and Aperture. You could lock a horizontal bar on any one of the three vertical rods in place and pivot so that it demostrated that for a given light and a desired aperture if you changed the shutter speed you then needed to change the ISO. For some this is second nature.