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Spirit's UnderBelly, processing the MI images
PDP8E
post Jun 25 2009, 03:01 AM
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Here is a work in progress.
I was working on a another thread (processing the envelope challenge for PFK) and thought I could use the same technique to 'see' underneath Spirit's deck with the MI.
While I don't fix the focus, the technique does what amounts to a smart contrast...
If anyone would like to to do a mosaic, i would appreciate it (I haven't done them enough to pull them off like you guys)
I will post the whole underbelly later, but here are the test images:
Attached Image
Attached Image

Attached Image


Cheers and thanks!


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CLA CLL
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dvandorn
post Jun 28 2009, 05:37 PM
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Actually, PDP8E is operating under a misapprehension. I can tell his logical thought process was "If you get greater depth of field by reducing your aperture and thus cutting down on the light entering the camera, maybe you'll get greater depth of field merely by reducing the overall light level." And that's a fallacious logic chain.

You see, in the physics of photography, it's the actual size of the aperture, and not the amount of light reaching the photosensitive surface, that determines your depth of field (i.e., the range of distance from the camera in which objects are in focus). Focus has to do with the collimation (i.e., the parallel-ness) of the rays of light when they hit the film/CCDs. The smaller the aperture, the less "spread" you get from a beam of light entering, say, from the upper-right corner of the lens and then painted into the bottom-left corner of the film plane. The absolute greatest depth of field comes from a pinhole aperture, since there is almost no practical room for the light from any given area in the field of view to spread across the width of the aperture.

I have a degree in photojournalism -- some things you learn empirically, even if you're not a physicist... smile.gif

-the other Doug

p.s. -- looking at PDP8E's other point, that reducing exposure time would increase depth of field, again that's not a truthful statement. The only thing that really increases depth of field is reducing aperture. If you increase the light on the subject, you can reduce aperture and thus increase depth of field, and perhaps at the same time you might need to reduce your exposure time in order to get a properly exposed image. That's the only way in which exposure time could work in with depth of field. But in general, photographers use exposure time to determine proper exposure (i.e., total amount of light) and aperture to determine proper depth of field. dvd


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“The trouble ain't that there is too many fools, but that the lightning ain't distributed right.” -Mark Twain
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Posts in this topic
- PDP8E   Spirit's UnderBelly   Jun 25 2009, 03:01 AM
- - RoverDriver   That's pretty impressive! Can you do the ...   Jun 25 2009, 04:56 AM
- - Astro0   Nice work PDP8E Here's a mosaic of your image...   Jun 25 2009, 11:34 AM
- - Astro0   Here are the variants that have appeared so far. A...   Jun 25 2009, 11:41 AM
- - Floyd   pdp8 Do you think think the focus deconvolution c...   Jun 25 2009, 06:04 PM
|- - PDP8E   Hi Floyd, (...nice weather you and I are having ....   Jun 25 2009, 06:32 PM
- - jekbradbury   This is something I did a few weeks ago using the ...   Jun 26 2009, 12:26 AM
|- - PDP8E   jekbradbury: wow! that is one groovy blind dec...   Jun 26 2009, 01:50 AM
- - PDP8E   the last one... Cheers   Jun 26 2009, 01:53 AM
- - Astro0   A quick and rough scaled down version of PDP8E...   Jun 26 2009, 03:48 AM
- - Stu   Absolutely awesome work you two. I would love to s...   Jun 26 2009, 05:39 AM
|- - PDP8E   Here is an off the wall idea to get better focused...   Jun 27 2009, 03:38 AM
|- - RoverDriver   QUOTE (PDP8E @ Jun 26 2009, 08:38 PM) ......   Jun 28 2009, 07:04 AM
- - Astro0   I was looking back at the MIs and got to thinking ...   Jun 28 2009, 06:50 AM
- - dvandorn   Actually, PDP8E is operating under a misapprehensi...   Jun 28 2009, 05:37 PM
- - tty   Is there any way to reduce the aperture external t...   Jun 28 2009, 06:07 PM
- - dvandorn   Partially closing the MI's lens cap has been d...   Jun 28 2009, 06:17 PM
- - PDP8E   Hey Other Doug, Thanks for keeping me on the stra...   Jun 28 2009, 08:00 PM
|- - RoverDriver   QUOTE (PDP8E @ Jun 28 2009, 12:00 PM) ......   Jun 29 2009, 03:12 AM
- - PDP8E   Here is the 1st peek under Spirit's deck taken...   Jun 30 2009, 02:41 AM
- - PDP8E   last image: Cheers <Astro0 please do your m...   Jun 30 2009, 02:43 AM
- - Astro0   It's an interesting technique PDP8E, but I won...   Jun 30 2009, 12:26 PM
- - PDP8E   Astro, first thanks for helping out with the mosai...   Jun 30 2009, 02:24 PM
- - jekbradbury   For those who intend to do serious work on attacki...   Jun 30 2009, 02:59 PM
- - PDP8E   This is brief report on a work in progress: focusi...   Jul 1 2009, 04:27 AM


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