Canon EOS 1D Mark IV Hands on Review- Part II- Intermediate ISOs - Indiawilds: Land of the Tiger. Conservation, Wildlife Photography, Communities

Sabyasachi Patra · #1 09-03-2010, 07:03 PM

Canon EOS 1D Mark IV - Hands on - Part II - Intermediate ISOs

I have been carefully monitoring the noise characteristics in my Mark IV. I noticed that though my images created with ISO 1250 has more noise than the ISO 1600 ISO images.

I decided to check the noise at all the ISOs. Since I couldn't find birds posing long enough for all the ISO settings, I decided to test it the frames without a subject. :-)

With the lens cap on, camera in aperture priority with aperture set at f4, using a remote timer, I clicked frames at all the ISOs. The viewfinder was shut to prevent light entering through it.

Processing:
The frames were processed in lightroom 2.6 (my normal software). I decided to pull up the exposure by 4 stops. That means, I opened up the images by four stops, further accentuating the noise. Since this is the same for all the images, it ceases to be a variable.

I decided to keep the noise reduction at default for all (Luminance 0, Colour 25). It doesn't matter, as it is same for all.

Sharpening: Again it is at default (Amount 25, Radius 0, Detail 25, Masking 0). I decided to keep it as it is, as that is how I process my images. Hardly any extra sharpening I do for my images. Also, sharpening has the potential to sharpen the noise and make it more prominent. Anyway, it is a default for all, and hence ceases to be a variable.

Crop: The images were cropped to 796x530. That means, these are what you find at 100% viewing size, popularly referred as 100% crop.

The images were not resized while converting.

I have uploaded images one in each thread, starting from ISO 100 till ISO 12800. The initial threads starting with ISO 100 will appear plain black. Only at later ISOs, the nosie starts showing up. So don't wonder what's happening here.

Now, over to you all for your conclusions. As far as I am concerned, my camera will be off for intermediate ISOs.
Cheers,
Sabyasachi