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Canon DSLR Challenge | all galleries >> Challenge 105: High Contrast (Hosted by Melbob) >> Challenge 105: Eligible > Eye Contrast
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2007-10-21 Jim H.

Eye Contrast


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Canon DSLR Challenge30-Oct-2007 00:28
I love the science aspect of this project of yours Jim and appreciate the explanation. - Kelly
ctfchallenge28-Oct-2007 21:18
Whew, Jim. I'm glad you're ok with my comment. I hate to not like something of yours. I usually like all of yours... ~Lydia
Canon DSLR Challenge28-Oct-2007 13:30
Don't be sorry to say that. It bothers my eyes too :) At a very small size, even smaller than the thumbnail, it begins to look "right". At this size, it's interesting, but not necessarily all that pleasing. Jim H.
ctfchallenge27-Oct-2007 02:15
I'm sorry to say that this hurts my eyes to look at. Perhaps enlarged and farther away from my eyes would work. Sorry. ~Lydia
Canon DSLR Challenge25-Oct-2007 13:45
Wow - looks like modern art! Well done Jim and really interesting explanation too! CJ
Guest 24-Oct-2007 19:25
Nice. A very different take on the challenge...
-Cat
Canon DSLR Challenge23-Oct-2007 06:57
I probably should have commented on what I did with this earlier. This is really sort of an experiment to see if I could produce a photo with a normal or even fairly low contrast look to it yet have the actual file be the ultimate in high contrast.

Here is an 8X enlargement of one area of the image:

http://i.pbase.com/o3/36/275736/1/87733642.zc1StL9x.IMG_1892clonedcolorcrop1HTX8.png

Right click that larger image and then save it to your computer. Then open it in your photo editor and look at the RGB values at any point. Also check out the histogram :)

This was done using Photoshop's "Color Halftone" filter and then some additional contrast increase to be sure there were no pixels containing anything other than totally "on" (255) or totally off (0) values for Red, Green, and Blue.

Back when I worked for the local newspaper, we had to create halftones of any image to be printed because there are no different shades of ink. At any point on the printed newspaper page, we only got black ink or nothing but bare newsprint.

For color printing, they usually use CMYK inks, but again, at any point, you can only have bare paper or ink - there is no in-between.

This image is sort of a demonstration of how something can appear to have a range of tones yet in reality, contain nothing but extremely high contrast. It's kind of a fun experiment.

You don't get all of the proper halftone tools with Photoshop's color halftone filter but I do believe that for printing, you can produce proper four color separations using the screen button in the "print with preview" dialog. But there's just no easy way to get the result of that process back into this kind of format. It's just sent to the printer.

I should play with it more and perhaps use Corel Draw or some other program to generate the image and then export it as a bitmap.

I chose the PNG format because it handles this sort of thing much better than JPG while producing a very small file. The size reported by PBase seems to be correct. The same image saved as a JPG was far larger.

Here's the Wikipedia page about halftones:

http://en.wikipedia.org/wiki/Halftone

Jim H.
Canon DSLR Challenge23-Oct-2007 06:57
Well I cannot suggest that this is not on-topic.... "RGB" raster indeed?

Fantastic Jim... too clever and love the title.

Jim, how does PBase go with reporting 'ping' file size? Got me intrigued?

~ Regards Melbob
Canon DSLR Challenge23-Oct-2007 06:57
I rather like this, Jim. Do you mind me asking how you achieved this? Best Wishes, Traveller