Where did the 18% gray card really come from?

[Sirius Glass]

In the 1940's Kodak touted the 18% grey card as an exposure calculating device for color photos. I recently reread Roger's and Frances' web page on the 18% gray card. I realized the most photographers do not realize why Kodak selected that particular shade of gray [Note Bene: not a lighter shade of pale].

Kodak selected the 18% gray card because that is the usual color of the Rochester New York sky!

By the way, the real reason that George Eastman founded Kodak in Rochester is because Rochester is the world largest natural darkroom! And not because his mother took in wash in the area for a living.

So now you know the truth behind two carefully guarded Kodad secrets! Aren't you glad you asked?

Steve

 

[Roger Hicks]

Dear Steve,

I'd be happier if you hadn't implied that your sources for this enlightenment were our site, or if you had made it slightly clearer that in 1941 Kodak were still touting film packets, not gray cards, so I don't know exactly when gray cards came out.

The Rochester sky story is entertaining, and I have heard it before; but it does not appear in the module you mentioned, though it may appear elsewhere on the site. At least, I don't remember putting it in the module in question, and I couldn't find it on a cursory re-read.

The 'largest natural darkroom' story is entirely novel to me.

Cheers,

Roger (www.rogerandfrances.com)

 

[Sirius Glass]

Roger,

Your site reminded me of these stories from when I worked at Kodak.

I did not mean to imply that your site was the source of the information; merely that it was the source of the inspiration.

g&a,
Steve

 

[Roger Hicks]

Roger,

Your site reminded me of these stories from when I worked at Kodak.

I did not mean to imply that your site was the source of the information; merely that it was the source of the inspiration.

g&a,
Steve

Dear Steve,

Thanks for the clarification. You and I are aware of at least some of the facts (and rumours, and good stories); you, quite possibly more than I. Others may be more inclined to take these things seriously.

Cheers,

Roger

 

[Sirius Glass]

Roger,

Should I make a signature that states:

Warning! These postings may be infected with irony! ?

Steve

 

[Harrigan]

Don't forget you can process your film in water taken from the Genesee river. I believe this is where Genesee gets its "special" water for producing Genny Cream Ale.

 

[DBP]

Is that why the trout up there look so silvery?

 

[Pinholemaster]

Gray card is 18% gray because of the discovery of two English scientists. They measured the reflectiveness of everything they could, averaged all the readings, and discovered the world is on average 18% gray. Thus all our light meters read 18% gray.

The same with color. Scientist measured the colors found through out the universe, stars, planets, interstellar gases and averaged the findings all together to discover the universe is beige.

Has nothing to do with Mr. Eastman's mother's laundry.

 

[Sirius Glass]

Don't forget you can process your film in water taken from the Genesee river. I believe this is where Genesee gets its "special" water for producing Genny Cream Ale.

My first day in Rochester I saw the Genesee river.

...​

From then on I would never drink Genesee beer.​

Steve

 

[Snapshot]

I thought that 18% grey was the natural reflectance of grass and greenery and that's why it was selected.

 

[Roger Hicks]

Roger,

Should I make a signature that states:

Warning! These postings may be infected with irony! ?

Steve

Dear Steve,

And add,

"This does not necessarily mean 'reminiscent of iron'."

Cheers,

Roger

 

[Daniel_OB]

18 % is around the border line dark-light tones. It is 2.7 times above reflectance of black velvet and around 2.7 times below reflectance of clear white with 98% reflectance.
Some meters (e.g. Leica meters) are calibrated for 18%, while some other for 12% (e.g new swconics), and some for 14% reflectance (do not know any example).
I beleive that invesigator knew densitometry when defined the number (18%).

www.Leica-R.com

 

[Photo Engineer]

The comment about Rochester sky is interesting. Kodak used the Washington DC sky as a standard for many years. IDK if they still do, but we had exacting measurments made in DC and used them for years in KRL.

Rochester is too dull.

PE

 

[Sirius Glass]

The comment about Rochester sky is interesting. Kodak used the Washington DC sky as a standard for many years. IDK if they still do, but we had exacting measurments made in DC and used them for years in KRL.

Rochester is too dull.

PE

Yes, Washington DC has the same sky affliction.

Steve

 

[Roger Hicks]

The comment about Rochester sky is interesting. Kodak used the Washington DC sky as a standard for many years. IDK if they still do, but we had exacting measurments made in DC and used them for years in KRL.

Rochester is too dull.

PE

Dear PE

Wasn't that a colour temperature standard, not a brightness standard? Or was it both? (You will know far better than I).

As for Rochester's dullness, Frances says that although you're right, it was still less dull than Hilton. (Upstate New York joke). She left for California immediately after graduating from Hilton Central School in 1962...

Cheers,

Roger

 

[Photo Engineer]

Roger;

It was, of course, the color standard. I was just adding to the 'merriment'.

The brightness standards were a black cat in a coal mine and a nuclear explosion (later updated to thermonuclear). Actually, I never heard anyone discuss the brightness standard. I remember several discussions on the subject, but nothing referring to the source of the standards for this.

Good old Hilton. I think I was there once, but I sneezed and missed it. Either that or it was such a dull day, no one could see it as the contrast was too low. I think that they have a statue of every person who has moved away. Right now there are more statues than people I understand.



PE

 

[removed account4]

i thought it was 18% gray because it was easy to calculate if you didn't have a card ... 2 stops darker than any human's palm ...

 

[DBP]

Yes, Washington DC has the same sky affliction.

Steve

I would say the sky is a bit brighter than that here today, with a slight bluish tinge. Visibility between 4 and 5 miles with the smog and humidity (49% at 92F). Slightly better than yesterday, though tonight we are expected to get a cold front, with all the usual fun - thunderstorms, high winds, rain, hail, and possible tornadoes.

 

[Sirius Glass]

i thought it was 18% gray because it was easy to calculate if you didn't have a card ... 2 stops darker than any human's palm ...

I don't know about this one. Are your hands clean?

Do they have to be clean? Its not like we are eating when we take photos.

Steve

 

[Murray@uptowngallery]

Genessee - ugh

I seem to recall they also had a 12-Horse Ale.

In school we assumed they had something to do with the contents of the bottle.

 

[DBP]

Dear PE

Wasn't that a colour temperature standard, not a brightness standard? Or was it both? (You will know far better than I).

As for Rochester's dullness, Frances says that although you're right, it was still less dull than Hilton. (Upstate New York joke). She left for California immediately after graduating from Hilton Central School in 1962...

Cheers,

Roger

Looks like a huge city compared to my mother's home town of Luttrellville, VA.

 

[AgX]

I tried to get hold of that `whiter shade of pale´ card, I finally was handed a black disc.

I’m puzzled by it. And is that tiny hole somehow a reference for the maximum brightness?

It does not fit in my camera bag anyway.

 

[removed account4]

I don't know about this one. Are your hands clean?

Do they have to be clean? Its not like we are eating when we take photos.

Steve

yes, it is true, you can try it yourself ...

 

[winger]

Isn't Genesee made in Utica by the bewery there? Along with Utica Club and Saranac (which isn't bad). Not that their rivers are any better. (disclaimer - I grew up near Utica)

 

[Murray@uptowngallery]

Then there was the (crazy?) rumor Reverend Moon owned Genessee Brewing ?!?