Photography - ISO Comparison

I went to a close friend's wedding over the weekend and took some photos of the blushing bride at the church ceremony. Looking in the display window, it looked great; good exposure, good crispness, in focus.. Sure, I didn't have a good seat, nor chose to move around for better angles, but I wasn't really in the mood to do that and wanted to try to enjoy the moment.

I came home and uploaded the photos. To my horror I found that because I was using a telephoto lens, less light was hitting the sensor, requiring me to increase my aperture to maximum and increasing my iso to 3200. Both things I dislike to do; while increasing aperture will result in bokeh, the photographer needs to ensure that the correct point of focus is made, otherwise the shot will be ruined with one's eyes unable to settle on the right focus point (should normally be on the eyes, but may be on the cheek/nose instead). With a telephoto lens (which allows incredible zoom), it becomes increasingly harder to keep your camera still and get the proper focus point. I already knew the dangers of a high iso: noise/grain. To the untrained eye, most people don't see it (noise), but for photographers in particular who study photos, noise is a very ugly thing, almost unprofessional. That's why I don't like Facebook photos because they normally are very grainey or are under exposed (very dark areas; normally the face). 

Today's entry is a comparison of different iso settings of the same picture, which is something that I should have done before and that i'd recommend. Why? In knowing how much noise will appear in your photo, will help you determine whether you want to make that much of a sacrifice. I believe that the result (how much noise) will differ depending on your individual camera; so this was all taken with my Nikon D300s on my 50mm f1.8 lens.

200 ISO - Basically Perfect

1250 ISO - The Threshold

2500 ISO - Noise is Noticeable (car siding and bricks of house)

6400 ISO - Unacceptable (noticeable even on the driveway)

So after doing an analysis of my photos (I had one for every step in ISO and just chose to show the major changes), I've found that, IF possible, try to keep your ISO at 200-500 for the best result. 1250 ISO is probably the highest ISO that I would go with, as the noise starts to creep into the photo. Anything  2500 and greater is probably not worth taking. This is all my opinion, people have varying levels of what is good or not, but again, this is more of an experiment for oneself to determine how much noise is acceptable for you.