Quantitative Spectral Response of Base Silver Halide

[Nodda Duma]

PE, this is probably mostly for you but of course others are welcome to help out.

As an optical engineer, I'm pretty particular about spectral data. So searching for the spectral response of base silver halide doesn't leave me very satisfied with the results I find on the internet or in my references at home. I've seen spectrographs from 100+ years ago, but surely measurements were performed in the intervening decades to higher fidelity (like a vertical log scale). Silicon detectors, for example, are very well-characterized and the spectral response of undoped silicon is readily available showing response out to 1150nm at which time silicon becomes transparent. I could draw that response from memory (as well as InGaAs, HgCdTe, etc) just from working for decades with imaging systems. But for silver halide ... just a vague "sees UV, Blue, and negligible response beyond that" .. whatever negligible means.

So I'm curious, could you direct me to a source for quantitative spectral response of silver halide? I'd love to see the whole UV/VIS/NIR spectrum. If I had that info, I could do some radiometric calculations which I'm playing around with.

-Jason

 

[AgX]

At your hand: Mees & James, Chapter 11 (not II)
(Not the most modern spectrographs, but a variety and better than what you stated above.)

 

[Nodda Duma]

Which edition? Chapter II in my edition is about the size of halide grains

 

[AgX]

Chapter 11 (just corrected my post above)

Silly Mees and James using roman figures for an arabic number...

 

[avb]

I’m confused. How do you get the uv-vis-nir spectrum of silver halides if they are reduced by that light to metallic silver?

 

[AgX]

It is a matter of time, or rather timeliness.

 

[Nodda Duma]

The wedge spectrograms in my 1942 edition are in Ch. XVIII starting pg 690, but aren't really quantitative. What edition do you have?

-Jason

 

[dwross]

The Theory of the Photographic Process, 4th ed. James, T. H., ed, New York: Macmillan Publishing Co., Inc., 1977

 

[Nodda Duma]

Curses! Ok off to amazon I go .. .


Thanks, you all have redeemed the internet for today.

 

[dwross]

or abebooks.com
https://www.abebooks.com/servlet/Bo...n=James%2C+T+H&cm_sp=snippet-_-srp1-_-title11

 

[Nodda Duma]

or abebooks.com
https://www.abebooks.com/servlet/BookDetailsPL?bi=14115346869&searchurl=tn=Theory+of+the+Photographic+Process&sortby=17&an=James%2C+T+H&cm_sp=snippet-_-srp1-_-title11

Yep, I saw that one's close to me so I grabbed it.

- Jason

 

[Photo Engineer]

I’m confused. How do you get the uv-vis-nir spectrum of silver halides if they are reduced by that light to metallic silver?

You expose them through a monochromator and then develop them. The silver image is a reproduction of the spectral sensitivity.

Attached is an example of one from about 400 nm to 700 nm. The right hand blip is an artifact due to harmonics. A B&L monochromator was used set to visible. UV is attenuated but not filtered.

PE

 

[Bill Burk]

The wedge spectrograms in my 1942 edition are in Ch. XVIII starting pg 690, but aren't really quantitative. What edition do you have?

-Jason

I have same edition.
Those are log vertical units! 1 2 3

 

[avb]

You expose them through a monochromator and then develop them. The silver image is a reproduction of the spectral sensitivity.

Attached is an example of one from about 400 nm to 700 nm. The right hand blip is an artifact due to harmonics. A B&L monochromator was used set to visible. UV is attenuated but not filtered.

PE

That makes sense to me - thanks!
Maybe this is just more of my ignorance but why is the spectrum (including the scale) washed out in the middle?

 

[AgX]

You expose them through a monochromator and then develop them. The silver image is a reproduction of the spectral sensitivity.

Important is the spectral energy spread of the light source. That makes it hard to compare plain wedge spectrographs from different labs.
Something typically overlooked here at Apug.

 

[Nodda Duma]

I have same edition.
Those are log vertical units! 1 2 3

Good catch, Bill.

 

[Photo Engineer]

That makes sense to me - thanks!
Maybe this is just more of my ignorance but why is the spectrum (including the scale) washed out in the middle?

There is zero sensitivity in the center, between about 500 and 700 nm, but the artifact causes density at about 700 nm.

PE