How Low Can You Go?
Unfortunately, the Owls have been rather quiet for the past week, so I decided to do something that I had been planning for some months…
I really needed to test the limits of my camera’s sensor. How far could I push the ISO before it failed to produce an acceptable image. I know that this limit varies considerably between camera models and with the Nikon D3s, I have one of the best. However, specification is not the point. If you are serious about photography then it is certainly helpful to know the limits of your equipment. Why? Well, at the very least, you will know when it’s time to pack your camera away and use your eyes and ears.
My test began on Saturday evening at the North Marsh Hide, Tophill Low. It was a dull evening with 100% cloud cover and no real sunset. For a few minutes, there was a beautiful cloud formation that looked very seductive through my 500 f4 lens. Eventually, I succumbed and made a series of exposures wide open at ISO 3200. Maybe some day, I’ll find a creative use for these clouds?
The following images were all taken from 100% crops from the original Raw image files. I have adjusted the colour balance, exposure and noise reduction in the Develop module of Lightroom to provide me with a suitable images for this blog. Note: these image files have not been uploaded to Flickr as most of them are for ‘record purposes’ only. The file sizes have been cropped to 500px x 375px.
This Moorhen swam by 17:45. At ISO 2000, the noise was not at all objectionable.
Two minutes later, a male Kestrel* flew over the top of the adjacent dyke. I was still using ISO 2000 which gave me a shutter speed wide open, of 1/320 second. Only just fast enough to freeze the flight of this raptor. Whew!
The fine plumage of a Greylag goose presented a good test when I raised the ISO to 3200. The D3s passed with flying colours (no pun intended).
The crows were vocal and active, searching for a suitable roost for the evening. At 17:53 and still using ISO 3200 I took this picture of a crow against the evening sky…
Cock pheasant was busy foraging on the margin of the lake. Luckily, it posed for one shot at ISO 6400 before returning to the undergrowth.
Took the final image around 18:30. The crows had settled down and this Common Buzzard flew across to a nearby tree to survey the territory below. This was taken at ISO 12,500 wide open at 1/200 second. The Buzzards wing-tips are blurred but still a remarkable result and the resulting file is more than suitable for a blog post.
So, what did I learn? Well, with my camera, ISO 6400 is probably the maximum ISO I would use to make a full sized image. However, it is good to know that I could use ISO 12,800 if absolutely necessary. More importantly, I had a simple reminder that the wildlife activity doesn’t suddenly subside when the sun goes down.
* [Many thanks to Alan Tremethick for correcting my i.d. My poor night vision me convinced this was a Sparrowhawk!]