ISOs and their use

[Jay Gould]

Artie, your blog entry of April 2nd (http://www.birdsasart-blog.com/ - You will read them!! - I do read them religiously :D - contains images made with the same camera and lens combo and ISO changes during the day between 400 and 800.

What prompted the changes?

Thanks, Jay

[Ákos Lumnitzer]

Probably changes in light conditions Jay. In fading light, or when the sun ducks in and out of clouds, or if you want to get fast shutter speeds, selecting a higher ISO gives you a faster shutter speed in a given situation thus you have a better chance of freezing action.

[Jay Gould]

Yup, but ......... does ISO 800 create so much noise that even in similar conditions do you go to ISO 400, and if so when do you go up and down the ISO scale? Are you only using the 800 to boost the shutter speed in relation to the subject matter and 400 or lower is preferred ISO?

[Alfred Forns]

In the words of Chas Glatzer .....Given the choice between noise and blur ... noise wins every time !!!

[Ilija Dukovski]

The camera model apparently can make a big difference when it comes to noise at high ISO.
On a D80 I get bit of noise already at ISO800,
yet, you will see many photots here at BPN taken
with D3 or like, at ISO 1600 and absolutelly noiseless.

The most important point however was covered by Al.
You can reduce noise in PP by a smart piece of software,
motion blur however is part of the record (signal) so it is
extremely hard to correct in PP (if at all).

Ilija

[John Chardine]

If I'm shooting manual or auto metering, I first set aperture to control DoF (I usually start at 1/3 stop below full open), then I choose an ISO reading that gives me the minimum shutter speed I need for the particular circumstances. This method was not possible with film and has revolutionised wildlife photography IMO. Most cameras out there today produce noise levels close to the theoretical minimum given sensor site size (my understanding from Roger Clark's excellent web site) and any residual noise can usually be dealt with in PP.

[Ilija Dukovski]

Another point when it comes to noise is to maximize the signal-to-noise ratio.
In other words the more light hits the sensors, the easier is to reduce the noise later
in PP without losing the picture quality (i.e. without throwing away the signal along
with the noise). So if noise is an issue I think it is good idea to try to overexpose as
much as you can without burning pixels.

[Ákos Lumnitzer]

Yup, but ......... does ISO 800 create so much noise that even in similar conditions do you go to ISO 400, and if so when do you go up and down the ISO scale? Are you only using the 800 to boost the shutter speed in relation to the subject matter and 400 or lower is preferred ISO?

Yes, ISO800 is very noisy if you use a simple point and shoot or some of the lower end camera bodies. The mid-high range bodies all handle noise relatively well at ISO800. I have an "old" EOS 30D and ISO800 is generally my choice of ISO nowadays for getting fastest possible shutter speed as often I shoot in areas with lots of trees and shade. When in the open and good light I will drop back to ISO400, sometimes even lower. I think my camera body would lock up if I suddenly picked ISO100 :D as I think in three years of use I would very, very rarely have selected that setting.

Nikon's new top end camera bodies are incredibly good at even ISO3200 and higher.

What Ilija said about overexposing is spot on. your review images on the camera screen will look overexposed and crummy, but checking the histogram and seeing it pushed as far right as possible will help minimize noise.

[Jay Gould]

Yes, ISO800 is very noisy if you use a simple point and shoot or some of the lower end camera bodies. The mid-high range bodies all handle noise relatively well at ISO800. I have an "old" EOS 30D and ISO800 is generally my choice of ISO nowadays for getting fastest possible shutter speed as often I shoot in areas with lots of trees and shade. When in the open and good light I will drop back to ISO400, sometimes even lower. I think my camera body would lock up if I suddenly picked ISO100 :D as I think in three years of use I would very, very rarely have selected that setting.

Nikon's new top end camera bodies are incredibly good at even ISO3200 and higher.

What Ilija said about overexposing is spot on. your review images on the camera screen will look overexposed and crummy, but checking the histogram and seeing it pushed as far right as possible will help minimize noise.

Thanks guys, over on the Canon 70 - 200 f/2.8 or f/4, Joe Milmoe posted an image at ISO 1600 which is more than acceptable for everything other than super high IQ photo art.

Cheers, Jay