Explaining ISO to a youngster
Apr 5, 2014 09:28:24 #
boberic wrote:
I know that this explanation may not be tecnically correct but it sort of is and it will make it easier for yoe little one to grasp. When it's dark, you can open the window all the way forever, and a blind person still can't see. When there is a tiny bit of light and the window is fully open very sensitive eyes (like a cat) can see a little. You get the picture. Eye sensitivity is sort of lihe ISO. Hope this helps.
This triggered the thought of sunglasses. Wearing them is like low ISO and taking them off or using ones with less tint is like higher ISO. Your eyes get the same amount of light (exposure).
Apr 5, 2014 09:32:41 #
Billynikon
Loc: Atlanta
I am sure the thought police will get me for a change in subject but I too have a 10 year old grandaughter and I wonder what yours is using for a camera. Mine was so impressed by my Leica LX5 that I got her the Panasonic equivilent two years ago. But I think she needs something else now
Apr 5, 2014 09:36:19 #
Pepper wrote:
I was explaining the exposure triangle to my granddaughter the other night and I was using the blinds on a window to demonstrate the shutter and the size of window to explain the aperture but when I got to the ISO and trying to explain that was how sensitive the sensor she wasnt getting it. Any simple analogies I could use to help her better understand ISO? Thanks guys.
Take the shade off of a bright lamp. Tell her to stand at a great distance then slowly walk toward the lamp bulb.
Apr 5, 2014 10:07:57 #
Frank W wrote:
How about just taking two pictures, one high ISO and one low ISO and showing her the difference.
:thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup: :thumbup:
Apr 5, 2014 10:26:39 #
Pepper wrote:
I was explaining the exposure triangle to my granddaughter the other night and I was using the blinds on a window to demonstrate the shutter and the size of window to explain the aperture but when I got to the ISO and trying to explain that was how sensitive the sensor she wasnt getting it. Any simple analogies I could use to help her better understand ISO? Thanks guys.
Do you have a light on a dimmer switch? Maybe show her that as you increase ISO, you turn the switch to demonstrate how it increases sensor sensitivity to light...
Apr 5, 2014 10:29:25 #
Apr 5, 2014 10:29:39 #
Pepper wrote:
I was explaining the exposure triangle to my granddaughter the other night and I was using the blinds on a window to demonstrate the shutter and the size of window to explain the aperture but when I got to the ISO and trying to explain that was how sensitive the sensor she wasnt getting it. Any simple analogies I could use to help her better understand ISO? Thanks guys.
I've used several glasses and a faucet. The amount I open the faucet is-the aperture, the length of time I opened it-the shutter, and the different sized glasses-the ISO, the larger glass being the slower ISO.
--Bob
Apr 5, 2014 10:30:52 #
I used sound as an analogy with my Audio/Visual class.
If you turn up the volume (Aperture) it amplifies what the microphone (lens) picks up.
If you turn up the gain (ISO) the microphone (sensor) picks up more background noise.
If you turn up the volume (Aperture) it amplifies what the microphone (lens) picks up.
If you turn up the gain (ISO) the microphone (sensor) picks up more background noise.
Apr 5, 2014 10:32:18 #
I have always used the bucket analogy for all my students from young to senior citizens.
The bucket is the amount of light to properly expose an image.
Too much in the bucket and it overflows - overexposure. Under fill the bucket - underexpose the image.
The hose you fill the bucket with is your aperture. Larger diameter, more liquid fills the bucket. Smaller diameter takes longer to fill the bucket.
The time you have the hose on is shutter speed. The longer you leave the hose on, the more light is let in. Vice-verse for shorter time.
Either way you fill your bucket, whether it is larger diameter, or longer time, there is only one amount to fill any particular bucket.
ISO is the bucket size. When you choose a bucket there is one specific amount that will fill that particular bucket.
When you are introducing the triangle to a ten-year-old, introduce the aperture and shutter speed relationship first. Don't worry about ISO. A fifth grader will have some background in fractions, so they may understand the concept of shutter speeds and halving the exposure. Go out and shoot until she gets the concept clearly.
Introduce her to ISO once she has the shutter speed/aperture thing down.
You DON"T need to explain noise, DOF, stopping action, that are achieved with changing the shutter speed/aperture until she understands how the proper exposure is obtained.
Noise, DOF, foreshortening, lens compression of the image, etc can all be illustrated through pictures taken later.
INTRODUCE CONCEPTS ONE AT A TIME, VERY IMPORTANT. Don't give too many at once. Get the two sides of the triangle before introducing the third. She is 10 years old, a linear approach to information is easier to build with than introducing too many principles at the same time. I am in the classroom on a daily basis.
The bucket is the amount of light to properly expose an image.
Too much in the bucket and it overflows - overexposure. Under fill the bucket - underexpose the image.
The hose you fill the bucket with is your aperture. Larger diameter, more liquid fills the bucket. Smaller diameter takes longer to fill the bucket.
The time you have the hose on is shutter speed. The longer you leave the hose on, the more light is let in. Vice-verse for shorter time.
Either way you fill your bucket, whether it is larger diameter, or longer time, there is only one amount to fill any particular bucket.
ISO is the bucket size. When you choose a bucket there is one specific amount that will fill that particular bucket.
When you are introducing the triangle to a ten-year-old, introduce the aperture and shutter speed relationship first. Don't worry about ISO. A fifth grader will have some background in fractions, so they may understand the concept of shutter speeds and halving the exposure. Go out and shoot until she gets the concept clearly.
Introduce her to ISO once she has the shutter speed/aperture thing down.
You DON"T need to explain noise, DOF, stopping action, that are achieved with changing the shutter speed/aperture until she understands how the proper exposure is obtained.
Noise, DOF, foreshortening, lens compression of the image, etc can all be illustrated through pictures taken later.
INTRODUCE CONCEPTS ONE AT A TIME, VERY IMPORTANT. Don't give too many at once. Get the two sides of the triangle before introducing the third. She is 10 years old, a linear approach to information is easier to build with than introducing too many principles at the same time. I am in the classroom on a daily basis.
Apr 5, 2014 10:55:51 #
Rather than more or fewer bees, how about big bees vs smaller bees
The big bees gather more light but they create a rougher textured picture (IE noisier)
The big bees gather more light but they create a rougher textured picture (IE noisier)
Apr 5, 2014 11:05:29 #
How about her using a crayon and two piece of paper of different texture. (One very smooth, the other rough.) This way she will get to see, feel, and be active in the understanding.
Draw two circles on both paper, being equal sizes, say 3-6 inch diameter. Have her fill in smooth one, with crayon. Do not tell her how to do it, and time her unknowingly. She will most like take her time and be very meticulously to get it fully covered with crayon.
Once done, inform her you timed her, and now she has to fill in the other rough one within the time of the other.
When she proceeds she will notice that the crayon is not filling the nooks and crannies of the paper. Rather it will be spotty or grainy looking after the time limit she has spent trying to fill in the circle.
Explain by raising the ISO you make the sensor (paper) from a smooth texture easily accepting the color (light) to an increased rough texture (less sensitivity to accept the color (light) in the cracks.) The out come is a grainy picture.
This way she can see the time is the same, the color is the same, the size of the picture is the same. The only difference is that the sensitivity of the sensor.
If further explanation is necessary, just say that the sensor starts out as a very grainy piece of paper. As you lower the number (ISO), it is taking out the roughness of the paper making the picture smoother, upon which the light strikes. Just like the crayon fills in on the smooth paper.
Hope it helps.
Draw two circles on both paper, being equal sizes, say 3-6 inch diameter. Have her fill in smooth one, with crayon. Do not tell her how to do it, and time her unknowingly. She will most like take her time and be very meticulously to get it fully covered with crayon.
Once done, inform her you timed her, and now she has to fill in the other rough one within the time of the other.
When she proceeds she will notice that the crayon is not filling the nooks and crannies of the paper. Rather it will be spotty or grainy looking after the time limit she has spent trying to fill in the circle.
Explain by raising the ISO you make the sensor (paper) from a smooth texture easily accepting the color (light) to an increased rough texture (less sensitivity to accept the color (light) in the cracks.) The out come is a grainy picture.
This way she can see the time is the same, the color is the same, the size of the picture is the same. The only difference is that the sensitivity of the sensor.
If further explanation is necessary, just say that the sensor starts out as a very grainy piece of paper. As you lower the number (ISO), it is taking out the roughness of the paper making the picture smoother, upon which the light strikes. Just like the crayon fills in on the smooth paper.
Hope it helps.
Apr 5, 2014 11:09:16 #
sshinn1 wrote:
Do you have a light on a dimmer switch? Maybe show her that as you increase ISO, you turn the switch to demonstrate how it increases sensor sensitivity to light...
I like that one!
Apr 5, 2014 11:12:52 #
Pepper wrote:
Thanks Fred, that's a good analogy. Where I failed was when she asked why not use a high ISO all the time and I got into the graininess you can get by using higher ISOs and I was struggling trying to explain it to her.
Just show her two side by side photos, one at 100 ISO and the other at maybe 3200 showing lots of noise. Just explain this is the trade off for more sensitivity. I don't think she or most of us need to know the technology behind sensors. An explanation and a visual of what it means is all that is necessary.
Apr 5, 2014 11:40:09 #
Furry bees. ;)
Pepper wrote:
I like it but how do you explain the grain one could experience at higher ISOs?
Apr 5, 2014 11:47:01 #
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