Exercise 7: Your Tolerance For Noise

For this exercise I fixed my camera on a tripod in front of my bookcase and took a series of photographs increasing the ISO setting with each shot. The subject I chose featured both light, dark, detailed and plain areas. I then examined each image at 100% to note the difference that the increased ISO setting had on each image.

ISO 200 - no noticeable noise

ISO 400 - no noticeable noise

ISO 800 - small amount of noise in shadow and coloured areas, particularly purple of Parr book and black areas.

ISO 1600 - noise starting to take on an artificial look, definition of writing on the books seems less sharp.

ISO 3200 - noise now obvious across whole of the image and now noticeable in lighter areas.

ISO 6400 - noise has a more speckled appearance and looks less natural.

ISO 12800 - noise very prominent and visible evident without viewing at closer magnification.

ISO 25600 - image appears very degraded throughout and decrease in saturation is evident.

Generally I would say my camera handles increased ISO well - I would have no issues using settings up to 1600 and 3200 does not represent significant degradation of image quality either. Often the ISO speed chosen is entirely dependent on circumstances when an image is taken - given bright enough conditions I would always choose the lowest setting possible as this gives the best quality and most versatile output for the final image. Recently I have began to shoot in automatic ISO mode in situations where the light is changing rapidly and a fast shutter speed is required - experience has taught me that increased noise in an image is a necessary compromise to achieving image sharpness.