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Re: Explain This ... Photo

Posted: Fri Feb 27, 2009 7:00 pm
by Mako Koiwai
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Re: Explain This ... Photo

Posted: Fri Feb 27, 2009 8:09 pm
by Bob Beamesderfer
That photo is flopped.

Re: Explain This ... Photo

Posted: Fri Feb 27, 2009 8:22 pm
by Mako Koiwai
Very Good! :D

And if I hadn't flopped it, someone would have said it's running the wrong direction ...

Re: Explain This ... Photo

Posted: Fri Feb 27, 2009 9:00 pm
by Will Kalman
Here, I flopped it back, recognize it now?

Image

Re: Explain This ... Photo

Posted: Fri Feb 27, 2009 11:05 pm
by Mike Simanyi
I'm with Kristoffer on this. Your sensor technology (inherent to *all* the current cameras - do a search on Bayer filters), resolution, sharpening, noise reduction and the angle of the light have conspired to create that effect. Kinda cool to see a real world example though, rather than just the basic theory.

Mike

Re: Explain This ... Photo

Posted: Sat Feb 28, 2009 12:42 pm
by Larry Andrews
I kinda like the 'relative motion' theory - but don't discount the automatic software component.

Reason I like the relative motion theory is that the right side cuts seem to be blurred on the ends - where the relative motion is parallel to the long side of the left side cuts. The left side cuts seem to be more focused on the ends - where they're parallel to the more clear right side cuts. So, the relative motion of the cuts seems to play a role in producing this outcome, paying appropriate respect to the remaining contributions of software/firmware/sensor response.

Another thing I seem to notice is the huge contrast difference between the left and right grooves. The right side seems to be much more black/white relative to the left grooves - perhaps this contributes to the effect?

Neat thread... :)

Anyone know when real racing starts?

Re: Explain This ... Photo

Posted: Sat Feb 28, 2009 12:49 pm
by Mako Koiwai
Blurring always reduces contrast. In fact when I'm doing blurred background panning shots, I now increase the contrast of the in-camera processing. See how the car is nice and contrasty (good blacks) and the background is soft and flat (no blacks):

Image

Re: Explain This ... Photo

Posted: Sat Feb 28, 2009 12:56 pm
by Larry Andrews
Mako, Sounds like you're thinking that loss of contrast implicitly is somehow equivalent to blurring. Guess that makes sense... So, would the difference in the relative angle of the walls of the cuts contribute? IE: since the left side tread is less perpendicular to the lens.

The thing I always have found to be an interesting photographic exercise is taking a picture of a fingerprint on a mirror. Right now I'm working to find ways to take pictures of glass with non-perpendicular broken edges. Oddly, both sides of the break are hard to image adequately under 30x magnification.

It's neat to be exposed to the thinking of a professional in a field I know precious little about. :) -la

Re: Explain This ... Photo

Posted: Sat Feb 28, 2009 8:16 pm
by Steve Collins
Larry Andrews wrote: Oddly, both sides of the break are hard to image adequately under 30x magnification.
Perhaps because the depth of field becomes tiny when using a macro lens. If that's the problem, one solution might be more light and a smaller aperature. Another would be to use a camera that can change the orientation of the film plane. Which lets you control the plane of focus on the subject. c.f. http://www.f8prophoto.com/tutorial-lfcm-1.html" onclick="window.open(this.href);return false;

Re: Explain This ... Photo

Posted: Sat Feb 28, 2009 9:23 pm
by George Schilling
This thread has been very enlightening. It's good to know that I have some intelligentsia amongst my friends just in case I need a consult. :)