uploaded by cfastie | January 08, 2013 17:38

Tags: mobile upload device:custom calibration neon sign iPhone homemade foldup 1000L/mm

Sample row: 192

Video row: 0


To the extent possible under law, cfastie has waived all copyright and related or neighboring rights to "JellyBellyRed".

Sets with this spectrum

NIST neon and neon sign

cfastie | 2 spectra | 0

Neon peaks from NIST database and peaks from a neon sign. It looks like I need more of the fainter peaks from the database.

NIST Neon and neon sign

cfastie | 2 spectra | 0

Neon peaks from NIST database and peaks from a neon sign


Red tube on neon sign. Homemade PLOTS foldup, iPhone 4S, ProCamera, 1/15 sec, f/2.4, ISO 800, DigitalZoomRatio - 4.23 x FocalLengthIn35mmFilm - 35 mm.

This all-red image confused the algorithm that auto-detects the red and blue ends of the spectrum. Jeff added a feature to manually flip just the image 180°....

I used this macro and the macro feature to calibrate this spectrum:
setup: function() { // code to run on startup $W.calibrate(2740,763,614.3,1493,671.7) }, draw: function() { // code to run every frame }

Update: Tried to recalibrate with: $W.calibrate(2740,762,616.4,1341,659.9) but the fit was poor, so returned to original.

_____ Learn more about this spectrum here:

Comments (7)

over 1 year ago, warren wrote:

There's not currently an easy way to use macros while on the Analyze page, i.e. with an already-existing spectrum. We should add that. I guess macros should then be marked as "for use with existing data" or "for use at capture time"...

over 1 year ago, cfastie wrote:

I used the brand new "Macro/scripting" feature under "More tools" to run the macro above to calibrate this spectrum. The peaks are easily recognizable as neon, so I looked up the wavelengths of the 614.3 nm and 671.7 nm peaks, and used Photoshop to learn how many pixels from the left edge these peaks were in the image. Now we can calibrate any known spectrum on any two peaks, not just CFL on those two peaks. This is going to be fun.

about 1 year ago, warren wrote:

Hey Chris - i just added email notifications for comments. Just wanted to say i "liked" your red spectrum here, it's great!

about 1 year ago, cfastie wrote:

Excellent! Just wait until you see what Ebert will do with a neon sign. So do you get now get a notification when I leave this comment?

about 1 year ago, warren wrote:

No, i have to add that next.

about 1 year ago, Non-Logged-In Jeff wrote:

OK, i believe all commenters (even unregistered ones) should now get notifications too. Would you care to test that?

about 1 year ago, Non too Fast wrote:

Hey Non, I got an email notification of your comment. So you might get a notification about this one. I am not logged in now.

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