Around the holidays I bought a Nikon D600, a pretty nice full frame camera. I ended up returning it and buying a Pentax K-5 instead. The Nikon would’ve been too expensive to buy lenses for, and I was more or less happy with the lenses I had on Pentax.
So I’ve been playing around with my K-5 for the past few months, and overall I’ve been very happy with it. The dynamic range is incredible (according to DXOMark it’s pretty much on par with the D600), which really comes in handy for me. The one thing that I gave up when returning the D600 was high ISO performance. Full frame cameras beat crop sensor bodies by a large margin. But is high ISO really that unusable on my camera? Before this weekend I never really put my camera to the test.
This weekend I ended up hiking at Pinnacles National Monument with some friends. During the hike we passed through a cave, which ended up being a really good test of my camera’s high ISO abilities.
My previous camera maxed out at ISO 3200, but I never really used it that high, since everything shot at above 800 had a ton of ugly sensor noise. Here’s one of the first shots I took at ISO 3200, while entering the caves at Pinnacles National Monument. I had my camera set at aperture priority, set at f/4, since I typically stop down a little bit to get my shots sharper. With those settings I could get a shutter speed of 1/8 of a second, which is a bit blurry with my shaky hands, and slow enough that even just hiking slowly causes motion blur.
From there I upped the ISO to 4000 and opened the aperture a bit to f/3.2. We were still sunlit in this area of the cave. From there I could get a shutter speed of 1/20th of a second, fast enough to get rid of the blur from my shaky hands, although you can still see some motion blur on my friends as they hiked through the cave.
As we traveled deeper into the cave, we entered areas with no sunlight. It was pitch black, and it was impossible to follow the trail without a flashlight. Here I cranked up the ISO to 6400 and opened the aperture on my lens all the way to f/2.8.
The rest of the pictures on these posts are at those settings. I didn’t use a flash on any of these pictures, since I didn’t want to ruin anyone’s vision, so everything was lit with just my flashlight. I’m pretty impressed with the detail that can still be captured under these tough lighting conditions.
It’s pretty easy to see where the light from the flashlight falls off. Everything outside of the view of the flashlight is dark.
Dynamic range and ISO are more or less inversely proportional. That is, as you increase the ISO you decrease the effective dynamic range of the camera. So I was actually surprised that this picture actually came out. This is almost a worst case scenario, with the ISO cranked up to ISO 6400 and a bright headlamp shined directly at my lens, I wouldn’t think that the face underneath the headlamp would show up.
Actually, now that I think about it more, I must have been shining a flashlight in that direction, which would’ve reduced the range enough for the camera to capture the detail in the face. Haha, so disregard what I just said.
But still, I’m quite impressed with this camera. Having the ability to shoot at such high ISOs creates the possibility for a ton of shots that I never would’ve been able to get on my old camera. I’m looking forward to a future of pictures in deep caves and underneath dark skies with this camera.