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Old December 11th 17, 04:34 AM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 4,018
Default New B&M 100lux headlight.

On Mon, 11 Dec 2017 13:31:17 +1100, James
wrote:

On 10/12/17 10:40, Oculus Lights wrote:
On Tuesday, November 21, 2017 at 2:34:34 PM UTC-8, James wrote:
https://www.bike24.com/p2144878.html


My ray traces shown
on the Learn More page on the Oculus website have literally no center
spot, virtually no red dots at all, ...


https://www.barrybeams.com/learn-more.html

On the Learn More page I see a screen shot of a "computer simulation".
I assume that is of the light projected horizontally against a vertical
surface. Given that, it will not illuminate the road surface evenly at all.

I also see a picture of a supposed NASA Rover with an Oculus flood
light, that shows a bright spot just in front of the vehicle.

Is that what I was supposed to see?


I think the rover photo is intended to show how the Oculus Light
improves illumination at a distance. I don't see that on the photo. I
find it very difficult to judge intensity from an image consisting of
different white levels. To be sure, I converted the image to false
color:
http://www.11junk.com/jeffl/pics/bicycles/Front-Light-False-Color/
Original image:
http://www.11junk.com/jeffl/pics/bicycles/Front-Light-False-Color/slides/occulus-rover.html
False color using the "16 colors" LUT (look up table):
http://www.11junk.com/jeffl/pics/bicycles/Front-Light-False-Color/slides/occulus-rover-false-color.html
Note that the false colorizing assumes that the ground is uniform and
of equal reflectivity across the viewing area. I'll spare you my
opinion of the beam pattern because I'm not certain that my criteria
is the same as NASA's.

You can make your own false color images using a Java program called
ImageJ. Instructions lifted from my previous posting at:
https://groups.google.com/d/msg/rec.bicycles.tech/wPP-6f7mJOE/75h2lv1aAwAJ
https://imagej.nih.gov/ij/
Load original image.
Convert to gray scale with:
Image - Color - Channels Tool
Set it for Grayscale, which should also set it for only Channel 1.
The image should now appear in gray scale.
Convert the image to false color with:
Image - Lookup Tables
Pick an LUT (look up table). I suggest 16 colors or BRGBCMYW.


--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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