Tag Archives: noise

Commentary, Equipment, Ideas

Megapixel Mania – An Extended Riff

11 Comments

I read (yet another… ;-) megapixel rant somewhere online yesterday, and it got me thinking again about the fixation on megapixels as a measure of camera “value,” and the odd and sometimes irrational ways that people respond to this issue. It is well known that over the past decade or more, as digital photography technologies have become more and more prevalent (displacing film in many areas), camera technology has continued to advance in many ways. Among these advances is the ability to increase the number of photosites on sensors of a given size – e.g. give us “more megapixels.”

The responses to this tend to fall into three broad categories: Continue reading Megapixel Mania – An Extended Riff →

Commentary

Experiment #2: A Hint

2 Comments

Here are the three source images:

The differences among them are obviously in the amount of noise that was added to the image. No noise was added to the first image – any noise there was in the original capture. 10% level “Uniform” noise was added to the second image in Photoshop. 20% “Uniform” noise was added to the third image in the same way.

The soft photograph was chosen to avoid masking the noise with a lot of other sharp detail – this image provides very smooth gradients from black to white, where noise is typically easier to detect. I also chose this image because it is nearly – but not quite – monochromatic. This meant that I could increase the effect of the noise by using color noise rather than limiting to monochromatic noise – and that the color noise would tend to be more visible against the nearly monochromatic background.

The original set of 6 jpgs includes two from each of the three versions shown here. For last-minute fun you could still visit the comment page and try to a) determine whether or not the differences are visible and b) which pairs of images are the least noisy, more noisy, and most noisy.

More information to come later this evening.

Commentary, Equipment, Photographs: Nature

Canon EOS 5D II: Notes on Today’s Photograph

3 Comments

Since today’s photograph (“Redwood Forest, Morning“) was one of the first landscape photographs I shot with my new Canon EOS 5D II, I was interested to see how the camera would perform and what print quality might look like.

This photograph was a bit trickier than may be apparent. It was overcast and early in the morning, I was in the bottom of a deep valley, the wind was blowing, and the light was constantly changing. In addition I used a 85mm lens (the excellent EF 85mm f/1.8) on a full frame DSLR, so I had to shoot at a rather small aperture for DOF reasons, necessitating a very slow shutter speed in order to work at my preferred ISO 100.

With all of those challenges, when I made the first small test print of this photograph last night I was very impressed with the level of detail in the photograph and I’m certain that it will work as a very good sized print – in fact, this particular image almost needs to displayed large.

When a new camera body is introduced there always seems to be a string of reports of poor performance. Sometimes there is some truth to the reports, but it is my opinion that many of the reports are the result of poor technique, unrealistic expectations,  obsession with “issues” that are irrelevant in actual photographs, and general mistrust of any Big Company that sells expensive camera equipment. I read these reports and think about them a bit, but I don’t assume that they are correct until I see evidence – preferably evidence that I produce myself. The first direct evidence comes from looking closely at photographs on the monitor as I work on them in ACR and then in Photoshop, but the real evidence comes when I make a print. After doing both of the above – and contrary to some rumors you may hear – there are no issues with noise in the shadows and the overall image – even with the increased number of photosites – seems excellent in every way to me.

Does my Canon EOS 5D II produce excellent image quality? Yes. Am I seeing unusual or troubling amounts of noise? No. Are banding problems in the shadows impairing my photographs? No. Do carefully made photographs using this equipment have the potential to produce excellent prints? Yes.

Am I pleased with the results from my 5DII at this point? Yes.

Commentary, Equipment

Notes on Today’s Photograph

Leave a comment

I have posted a revised version of this message above.