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View Full Version : Tinkering with Refraction (FYI)



silver1985
08-06-2016, 04:06 AM
Like to tinker!

FYI

This is a computer simulation of an image that was effected by refraction by a 3mm thick piece of glass (at 45 degree angle), using a 20 MegaPixel (4.1 um pixel pitch) sensor.

Comments welcome!

PS: It's wasn't my cataracts!

jfines69
08-06-2016, 04:17 AM
The refraction technique on that one is not to good... The nonrefracted looks much better!!!

willbrooks
08-08-2016, 03:22 PM
Amazing the difference. This entire discussion about light refraction through glass has been very educational.

silver1985
08-08-2016, 05:19 PM
As an afterthought of posting this new thread on "refraction", I started to think that if an image can be created (by computer simulation) that displays the effects of refraction (i.e. the blurry, or out-of-focus appearance of the image), it would be possible to create a "corrected" image obtained from the "axial lighting" method. This would be possible by using a reverse process to "un-shift" the refracted RED, GREEN, and BLUE matrices, to synthesize a "corrected" RGB matrix (image).
Although doing this would probably be of more interest as a "hobby, or science fair project", than for any utilitarian purpose.
For anyone interested enough to read this thread, I would like to add that I am curious enough in this matter that I would appreciate someone Emailing me an uncompressed image file (i.e., TIFF, etc.) that was created with an 18-20 MegPixel sensor, and has an uncompressed file size output of 10 to 15 Mb size. I would like this type of file to computer-simulate the refraction/RGB shift effects on a "recorded uncompressed camera image" using a glass plate of 1 mm thickness in the "axial lighting" set-up.

Ordinary Fool
02-15-2017, 04:03 PM
What are the dimensions of that sensor having a 4.1 um pixel size?

silver1985
02-18-2017, 06:43 PM
Checkout the thread on "Axial Lighting"! for a full discussion.

1985...this seems logical, but unfortunately the physics goes the other direction. Rather than the MP rating, it is the pixel pitch that is relevant in these considerations. The 80MP IQ180 has a Large Format (LF) sensor, with dimensions 53.9mm x 40.4mm. The sensor has 10,328 x 7760 pixels, such that the pixel pitch is about 5.2um. These are rather large pixels. Compare this with a 20MP Canon 70D. Its sensor is 22.5mm x 15mm, with 5472 x 3648 pixels, such that the pixel pitch is 4.1um. The smaller pixels of the 20MP sensor make most optical considerations more difficult. The 20MP camera will actually require a bit thinner glass to have similar performance to the 80MP camera.