Are transmission graphs relevant for you when selecting binoculars? How? (1 Viewer)

[elkcub]

The

For those who are interested, Indiana University conducted a research project aimed at isolating just which monochromatic wavelength is used by the himan eye when bringing an object to sharp focus. It turns out to be 572nm, which is somewhat close to the wavelength area representing the eye’s primary photopic response, but still somewhat removed enough for the difference to be significant when determing the dioptric value of ophthalmic lenses. The photopic peak response is said to lie between 555nm and 560nm (560nm is the ISO reference).
B

According to THIS Wiki article, "The standard luminous efficiency function is normalized to a peak value of unity at 555 nm," and all texts that I'm familiar with say the same.

Could you provide the journal article, or reference to it, for the Indiana U. research study?.
Thanks,
Ed

Note: 572 nm is the peak sensitivity of the L (long wavelength) cone cell, which may account for the Indiana results.

 

[bsantini]

The

According to THIS Wiki article, "The standard luminous efficiency function is normalized to a peak value of unity at 555 nm," and all texts that I'm familiar with say the same.

Could you provide the journal article, or reference to it, for the Indiana U. research study?.
Thanks,
Ed

Note: 572 nm is the peak sensitivity of the L (long wavelength) cone cell, which may account for the Indiana results.

Larry Thiobos, Indiana University

 

[elkcub]

I'm familiar with Larry Thiobos' work. However, you still need to provide a journal article, book, or grant/contract report.
Thanks,
Ed

 

[Maljunulo]

Does anyone know the wavelength resolution of the average person’s vision?

Is the difference between 555 nm and 572 nm obvious? How about 555 nm and 560 nm?

 

[bsantini]

I'm familiar with Larry Thiobos' work. However, you still need to provide a journal article, book, or grant/contract report.
Thanks,
Ed

 

[elkcub]

Please provide the full set of viewgraphs as shown below for the presentation he made on Chromatic Aberration the year before in Whistler, BC.
Thanks,
Ed

 

[MiddleRiver]

Does anyone know the wavelength resolution of the average person’s vision?

Is the difference between 555 nm and 572 nm obvious? How about 555 nm and 560 nm?

Color vision - Wikipedia

en.wikipedia.org

 

[Maljunulo]

Thank you. I should have read that first. I suspected it might vary with sensitivity.

"Sufficient differences in wavelength cause a difference in the perceived hue; the just-noticeable difference in wavelength varies from about 1 nm in the blue-green and yellow wavelengths to 10 nm and more in the longer red and shorter blue wavelengths."

 

[MiddleRiver]

I have found it very interesting to superimpose transmission graphs on eye sensitivity.

 

[Maljunulo]

I have found it very interesting to superimpose transmission graphs on eye sensitivity.

Indeed.

 

[Scott98]

Color vision - Wikipedia

en.wikipedia.org

View attachment 1527509

yay! Thank you for posting this, I was too lazy to seek out the graph on the internet. My fading memory served well - just as as I thought, the eye is 10x more sensitive to green than the red & blue colors at the extreme ends of the visual spectrum.

Now, consider how worked up people get about a 5 or 10% difference in the transmission graph in blue or red - it's trivial.

 

[MiddleRiver]

yay! Thank you for posting this, I was too lazy to seek out the graph on the internet. My fading memory served well - just as as I thought, the eye is 10x more sensitive to green than the red & blue colors at the extreme ends of the visual spectrum.

Now, consider how worked up people get about a 5 or 10% difference in the transmission graph in blue or red - it's trivial.

I am not a vision scientist so although you are probably right, I can't speak to that. If you compare the diff mfg 'curves', there are obviously differences and users certainly report differences (Leica 'warm/red' vs Zeiss 'cool/green' etc.). So I agree that the sensitivity curves suggest that it's not that important, but how we perceive those subtle differences may in fact be more important than a graph depicts? I'm reminded of the audiophile's arguments that we can hear diff between digitally sampled music and analog. Or that even frequencies (as per better audio equip/speakers, etc.) which are out of our hearing range, may affect overtones or harmonics which DO affect the listening experience. So... I really dunno what it all means.

 

[Paultricounty]

So whats the take away here? Is it that when peak transmission numbers that are within a few percentages, the higher doesn’t mean the binoculars will have a perceived brighter image? Therefore a binocular with 88.5% can have a perceived brighter image than one with a 91%, depending where on the spectrum it peaks and how flat. That’s not even to say that we could take two identical binoculars from a manufacturer, both made from the same lot ,yet one could have an 88.5% and the other 90% and we still couldn’t perceive which is brighter. Then we could , and have considered how sensitive the individual is to what wavelength. So we can have someone who can see a brighter image with a 88% transmission (if it’s in that individuals sensitive area) than in a 91% transmission. Color perception a whole other story.

 

[Maljunulo]

Isn’t it odd that our eye sensitivity has evolved to be fairly close to the solar irradiance curve. (in the visible range)

 

[Paultricounty]

Isn’t it odd that our eye sensitivity has evolved to be fairly close to the solar irradiance curve. (in the visible range)

A fascinating conversation in itself. If our sun was slightly warmer or slightly cooler our eyes would’ve evolved with different spectrum sensitivity. Then the illusion that we see everyday and believe as reality would be completely different.

Paul

 

[Maljunulo]

A fascinating conversation in itself. If our sun was slightly warmer or slightly cooler our eyes would’ve evolved with different spectrum sensitivity. Then the illusion that we see everyday and believe as reality would be completely different.

Paul

Exactly.

“Reality” is a rather slippery thing.

 

[Scott98]

A fascinating conversation in itself. If our sun was slightly warmer or slightly cooler our eyes would’ve evolved with different spectrum sensitivity. Then the illusion that we see everyday and believe as reality would be completely different.

Paul

yes, gardening is another hobby for me and when you get into horticultural lighting you find the sensitivity curve for plants is directly opposite of our eyes - it's a U-shaped curve. Red and blue penetrate the ocean depths while green is filtered out by the water - so photosynthesis in all plants utilizes red and blue more than green. The first organisms to evolve photosynthesis ability were in the oean. I think most plant leaves look green because they're reflecting more green light and absorbing red and blue.

 

[Maljunulo]

yes, gardening is another hobby for me and when you get into horticultural lighting you find the sensitivity curve for plants is directly opposite of our eyes - it's a U-shaped curve. Red and blue penetrate the ocean depths while green is filtered out by the water - so photosynthesis in all plants utilizes red and blue more than green. The first organisms to evolve photosynthesis ability were in the oean. I think most plant leaves look green because they're reflecting more green light and absorbing red and blue.

I think this is a very important (if subtle) point.

Because most plants reflect green light, does that mean that we can say that they are green?

I’m not sure.

 

[Paultricounty]

I think this is a very important (if subtle) point.

Because most plants reflect green light, does that mean that we can say that they are green?

I’m not sure.

The green colour that we see in plants is the result of chlorophyll, a pigment that is used by plants to absorb light energy for photosynthesis. Chlorophyll absorbs red and blue light, but reflects green light back off of the leaves. This is why plants look green to us.