by David W. Powell
Real World ISO
If you do all of your shooting with a cell phone or tablet (mobile device), read no further. Your device takes care of this for you.
I think it is a good idea to test your camera(s) to determine its useful ISO range. If you try reading about or YouTubing this stuff, it gets pretty deep in the weeds very quickly. To me, what matters is the deliverable image. My standard is a 16×20 print. Yours may be viewing on a tablet, computer screen, or a contest somewhere, in which case you need to know what the contest standards and requirements are.
Here is what I recommend doing with each of your cameras in the lowest lighting situation you would normally use. Each device and setup only take a few minutes.
Tripod your camera and use a cable release or remote shutter activation. I often shoot in normal room lighting so that is what I used for this demo. It’s my kitchen countertop with mixed florescent and indirect daylight. The sequence goes from ISO 50 to ISO 25,600 in one stop increments. I set my Nikon 24-120 mm F4 zoom lens at 48mm and F8. I used a Nikon D500 with 24×16 mm (2/3) sensor… a nice camera, especially for bumping up ISO. With the camera set on manual exposure control and using the internal meter to set basic exposure at ISO 100, I made sure the histogram went all the way from left to right. This is important for a test such as this one. All of these shots are straight from RAW and unoptimized in any way.
ISO 50 – 2.5 sec.
ISO 100 – 1.3 sec.
ISO 200 – .8 sec
ISO 400 – 1/3
ISO 800 – 1/6
ISO 1600 – 1/13
ISO 3200 – 1/25
ISO 6400 – 1/40
ISO 12,800 – 1/80
ISO 25,600 – 1/160
Check it out and please let me know what you think. We have an 8-stop push and a 2-stop cut to the camera’s basic ISO of 100. The test showed me I can shoot to ISO 6400 with little grain or noise build up.
It’s the shot that counts, not the test.
Nice article. The images really tell the story. Just out of curiosity, do your 16″x20″ prints exhibit the same level of noise-tolerance as your projected images? That is, are you comfortable shooting at 6400 ISO if you’re planning to make prints?