ISO is comparable to the film we used to buy for our cameras. We could buy different ones like, 100, 200, 400, 800, etc. The lower the number the lower the sensitivity of the film and the finer the grain in the shots you’re taking.
In our digital cameras it means the same thing. Hope that helps.

valleylynn said:ISO is comparable to the film we used to buy for our cameras. We could buy different ones like, 100, 200, 400, 800, etc. The lower the number the lower the sensitivity of the film and the finer the grain in the shots you’re taking.
In our digital cameras it means the same thing. Hope that helps.

I think it will help. I'm going to need to take notes -- that way some of this will stick in my brain... MR

I've always been a note taker but it seems nowadays I forget where I put the notes. *sigh*

Or I put them in my pocket and then absent-mindedly take them out when I'm talking with someone and shred them... But I think just the exercise of writing things down helps them stick in my brain... I'm trying! ("Yes, Dear, Very..." is a response I heard a lot in my youth...)

I guess this is just sort of a "point of interest," not really useful in my mind, but I googled and found this regarding ISO --

"ISO stands for International Standards Organisation and it refers to the industry norm for sensitivity of emulsion based film, with 100 ISO being not so sensitive (and the standard ISO used by most people) to 1600 ISO which is extremely sensitive to light. "

And just want to say, I'm in the same boat as far as all of this just not sticking in my mind... even though quite a few years ago I had a pretty decent (film) camera and seem to remember having it all down pat! I need to focus more than the camera here... The Canon camera that I have was a Christmas present several years ago that my husband basically insisted that I needed because I was constantly taking pictures of the flowers and plants and bugs in the garden with our Sony Cybershot... and despite my protestations that I didn't even know how to use a lot of features on the Sony, he was adamant! So now I have this really, really nice camera that is a pain to haul around (definitely doesn't fit in my pocket when I'm in the garden like the Sony) and I've become somewhat paralyzed by the guilt of not using it. (Life must be so simple for single people )

Good to find this thread.

Weedwhacker ...

Weedwhacker said:So now I have this really, really nice camera that is a pain to haul around (definitely doesn't fit in my pocket when I'm in the garden like the Sony) and I've become somewhat paralyzed by the guilt of not using it. (Life must be so simple for single people )

I'm married to a whole community of people which can multiply the guilt. I'm allegedly in charge, but all that means is I have to make sure everyone else is happy!

An "outsider" gave us the camera, and I'm supposed to set a good example, too... So yes, be grateful. and now ten years later see if I can do something with it.

Also, it eats batteries (I have to ask what happened to the re-charger we had) and the lens cap is always swinging around and getting in the way... (gripe. gripe) But otherwise, it's really a great camera and I'm doing my best to be happy we have it. I'm still looking at the manual, but haven't sat down with it and another piece of paper to start the translation process... (Maybe I can get it published? Very different venue! )

Think of ISO as a sift or a screen. A really low ISO number is like a very fine mesh screen. You can pour liquid like chicken stock through a fine screen and it will capture all the "junk" in the screen, but it takes longer.

A really high ISO number is like a sift with really big holes. The water flows right through but so does a lot of the trash.

The high ISO can capture more light and therefore works in dim light, but the "trash" means the image isn't as clean and sharp.

If you have a lot of light, then use the best sift you have, and that means ISO 100. It's produce the cleanest image.

That explanation makes it clear as can be. Thank you Dave.
So if you are using ISO 100, do you set the shutter speed slower to gather more light/detail?

dave said:Think of ISO as a sift or a screen. A really low ISO number is like a very fine mesh screen. You can pour liquid like chicken stock through a fine screen and it will capture all the "junk" in the screen, but it takes longer.

A really high ISO number is like a sift with really big holes. The water flows right through but so does a lot of the trash.

The high ISO can capture more light and therefore works in dim light, but the "trash" means the image isn't as clean and sharp.

If you have a lot of light, then use the best sift you have, and that means ISO 100. It's produce the cleanest image.

Dave, thanks for explaining it that way. We'll get there! MR

Helpful illustration. Also like having the technical definition. I hope to keep learning.

Back in the olden days when using film, we called ISO, ASA (American Standard). You would choose different film with different ASA settings for specific situations. The lower the setting, the less light sensitive and the higher the ASA, the more light sensitive.

As Dave mentioned, the lower the ASA/ISO the more detail you'd get and needed a lot of light or exposure time. The higher just the opposite, less detail and less light required. Essentially, the low ASA/ISO film was for shooting polar bears at high noon in snow and the high ASA/ISO was for shooting black cats in coal cellars at midnight.

There were also other films available with mid-range ASA/ISO.

There were actually a few ways of getting a finer grain with high ASA/ISO film. How film worked was there would be a light sensitive emulsion on a piece of acetate. The thicker the emulsion the lower the ASA. The thinner the emulsion the higher the ASA. When developing film or printing film you had to be in a darkroom so all us old timers became very adept at doing things blind. We would have to in total darkness, take the film out of the camera, wind it on a spool that kept the film from touching, then put the wound film in a light proof developing tank, put the top on that and then you could turn on the lights.

http://en.wikipedia.org/wiki/D...

Next you'd mix up your chemicals and get it at a specific temperature. What the chemical essentially did was eat off portions of the emulsion that was exposed to light. The emulsion it ate off depended on how much exposure it had. There were charts for temperature and time needed to develop the film.

So one way to get finer grain with high ASA film was to develop it extremely slowly with the chemicals at a very low temperature so the eating away of the emulsion was very slow and not taking off large chunks quickly.

Wow !!! Good lesson there Anne.
ISO is one of those fundamentals we need to begin to understand to do better photography.

I decided I needed a better understanding of "Macro" and how it is used in photography.

Here is Wikipedia's definition

"Macro photography (or photomacrography[1] or macrography,[2] and sometimes macrophotography[3]), is extreme close-up photography, usually of very small subjects, in which the size of the subject in the photograph is greater than life size (though macrophotography technically refers to the art of making very large photographs).[2][4] By some definitions, a macro photograph is one in which the size of the subject on the negative or image sensor is life size or greater.[5] However in other uses it refers to a finished photograph of a subject at greater than life size.[6]

The ratio of the subject size on the film plane (or sensor plane) to the actual subject size is known as the reproduction ratio. Likewise, a macro lens is classically a lens capable of reproduction ratios greater than 1:1, although it often refers to any lens with a large reproduction ratio, despite rarely exceeding 1:1"

So I guess for my purposes it is taking a picture of a very small object and having it appear larger than it is in nature on the finished photo.

Using the built in "Macro mode" on the features on the camera allows me to get a "close up" of my favorite plant without having to enlarge the normal photo image.

I do know more complex cameras allow you to add a separate lens which will give you closer, better and more detailed photos but they come with a hefty price tag.

Is that about right?

That's about right, but as I said previously, today's digital cameras do a pretty good job. With some you can do manual focus but requires a tripod because you have to be dead steady. This picture was taken with my Canon Cybershot using manual focus.

Manual focus "MF" a whole new subject for a different thread.

Question. After seeing that beautiful photo of a zinnia/dahlia?, how would you get a depth of field that would show the detail from the front to the back of the flower. All of it in perfect focus.

I picked up this from the original request to add the forum. I don't think it was answered

Weedwhacker said:
One thing in particular that I'm wondering is, how much advantage is there to getting a macro lens as opposed to using the macro setting on the camera, or using a zoom lens.

Wanted to put it into this thread as it is a great question.

To answer your question Lynn, what you are talking about is depth of field. Depth of field can be dependent on a number of factors but the main way to get more depth of field is with f-stops which essentially refers to how big the hole in a lens is that lets the light into your camera. The lower the number the f-stop the bigger the hole or aperture. The higher the number the smaller the hole or aperture. Combined with shutter speed, which is the length the time the shutter stays open is where depth of field is born so to speak.

So for simplicity's sake, (which is to say this isn't the whole story) back to the black cat in the coal cellar at midnight. In order to photograph that cat you need a very large (but small number) opening/f stop and a very long shutter speed with a high ASA .. or with the polar polar bear at noon in the snow, a very small (but high number) opening/f stop and a very fast shutter speed with a low ASA.

Here's a link about it all:

http://www.picturecorrect.com/...