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Camera for the Web - Comparison

We propose that for all practical purposes, a 2 mega-pixel digital camera makes images for the WEB that are indistinguishable from images made from any film camera.

Here is an image shot with my new Leica that we can compare with the digital camera.

L4-15.jpg

There are 3 versions of this picture. One was taken with the Powershot S100. There are two versions of the film based image. First the one above was scanned with the Canon FS2710. The second was from the Kodak Photo CD done by our local consumer photo finisher, Wolf Camera.

Here are all three images on one page for comparison. I suspect you would agree, that there are subjective differences between the three images, but each seems equivalent to the other in edged definition, detail, color saturation, and tonal range. There are differences in color and depth of field.

The CanoScan image is of the highest quality. Here is a small section of the original scan that image showing the label on the ladder. The label is clearly a CAUTION sign. This level of detail does not exist in a 2 mega-pixel image from the S100. However it is lost in the final image as you can see below. Thus, the there is little difference between the WEB images from both cameras. Significant detail is lost as the image is downsized to fit on a WEB page.

label-best.jpg

By the time the image is converted to the appropriate size for the WEB the detail captured by the CanoScan is lost. Here is a blow-up of the labels from each of the final images:

CanoScan
web-canoscan.jpg
PhotoCD
web-photocd.jpg
S100
web-s100.jpg

From these blowups, we can conclude that the S100 and the CanoScan images are of about the same resolution, while the PhotoCD version is slightly inferior.

These images were made by making a screen print of the blown up images (500%) in Photoshop and capturing the resulting clip-board image in Paint. In this way we can see the individual pixels.

Experimental Technique

The S100 image was used as reference. It was taken at the highest image quality, producing a 2.0 MB file of a 1600 x 1200 image at 72 dpi. The other pictures were matched to this one in terms of picture coverage (magnification). The full frame was scaled to 500 pixels high.

The Photo CD image is of relatively poor quality - suitable for WEB snapshots only. The image was cropped slightly to have the same final magnification as the S100 image. It was a 760 KB file of a image at 72 dpi. The image 1488 x 992 at 72 dpi. It was cropped to the same vertical magnification and then scaled to 500 pixels high.

The CanoScan image was a 27.5 MB file of 3888 x 2591 at 2720 dpi, 8-bits/pixel. The image was cropped slightly to have the same final magnification as the S100 image. This image was scaled in PhotoShop to 500 pixels high ant 72 dpi for the WEB picture.

There are other differences besides the available detail in the images. This is discussed on the page showing all three images.

The digital cameras produce images with excellent edge definition, no grain and loose detail particularly in the shadows and high lights. Color accuracy can be suspect and dimensional distortion may exist depending on the model. However, taken by them selves they make fine images for the WEB with huge benefits in work flow. I wouldn't be without one.

Last modified: Wed, 07-Nov-01 08:15:31 PST