How do you decide which ISO speed to use?

[robmiller]

Always remember that a noisy shot is better than a blurry one, so don't be afraid of using ISO1600 or even ISO3200 if that's what it takes to get a shutter speed that will freeze motion or a depth of field large enough for your subject.

 

[mcwildcard]

Is ISO3200 really workable for a decent photo though?

 

[-RV-]

Is ISO3200 really workable for a decent photo though?

A noisey photo is always preferable to no photo, or a blurry one. It would be better if you didn't have to choose, but sometimes there is no choice at all.

 

[JBuk]

If the shutter speed doesn't match the focal length then increase ISO.

depending on what and how you are shooting of course and if you are using IS

Is ISO3200 really workable for a decent photo though?

it is on my 5D

 

[Scam]

Is ISO3200 really workable for a decent photo though?

This is my point (that i ranted about in another thread). If your choice is to use ISO3200, or get a shaky shot, or even no shot at all.. why would you even think twice about using a higher ISO? The ISO argument comes up when it's a necessity.

 

[platypus]

I always find the water / bucket / pipe / tap analogy to work well in describing how a camera works and how you can work out whats best for you...

Bucket - sensor
Bucket size - ISO
Time to fill bucket - shutter speed
F-stop (aperture) - pipe thickness how quick/slow water flows to bucket
Tap - shutter

These can all be set in a variety of way to achieve the same shutter speed, but results will differ. A higher ISO means the bucket will be full quicker than the same settings on a lower ISO.

http://www.digital-photography-in-focus.com/exposure.html

That is a great link, thanks. Does anyone think it's maybe a good idea to start putting a sticky of good photography links together?

 

[alexisonfire]

autoiso manual when needed to underexpose

 

[Gregeff]

I always find the water / bucket / pipe / tap analogy to work well in describing how a camera works and how you can work out whats best for you...

Bucket - sensor
Bucket size - ISO
Time to fill bucket - shutter speed
F-stop (aperture) - pipe thickness how quick/slow water flows to bucket
Tap - shutter

I find that considerably more complicated than how the camera actually works!! lol

 

[robmiller]

Is ISO3200 really workable for a decent photo though?

Infinitely preferable to a blurry shot at ISO800.

 

[Sic]

I find that considerably more complicated than how the camera actually works!! lol

hah, you're not alone with that one

 

[robmiller]

Because it's just switching terms about, it doesn't actually simplify the concept.

The (bucket|sensor) requires a certain amount of (water|light) to be (full|correctly exposed). You can either throw a large volume of (water|light) at it (big hosepipe|big aperture) for a short amount of time, or a small volume of (water|light) at it (small hosepipe|small aperture) for a long time. A (small bucket|more sensitive sensor) requires less (water|light), so if you (decrease bucket size|increase ISO) then you can be done in a short amount of time.

Same concept, different words.

 

[platypus]

Well, I said the link was useful, not the analogy.

 

[-RV-]

Well, as most people that are starting out don't understand the relationship between ISO/Aperture/Shutter speed I thought its quite a simple way of visualising it. It will help them to learn what each means relative to the other.