Non-photo blue • Hacker News Board

Re: Non-photo blue

#41

Post by ChuckMcM » Sun, Nov 22, 2015, 4:16 AM UTC

lfowles wrote: post #32

ChuckMcM wrote: post #8

And my engineering notebooks from the EurekaLabNotebook company use this color for the grid which is a bit disconcerting if you make a copy of the page and the grid disappears and you have only your writing and diagrams.

Interesting, do you have a picture? Most engineering paper has a grid printed only the back so it doesn't show when scanned, but I haven't seen it in blue.

These are the folks I get them from, http://www.eurekalabbook.com/BlueQuadEnlarge.html and a picture of the Blue printed one.

Re: Non-photo blue

#42

Post by Tinyyy » Sun, Nov 22, 2015, 4:29 AM UTC

percept wrote: post #40

I made it my new HN topcolor--not bad.

How much karma do you need to customise it?

Re: Non-photo blue

#43

Post by percept » Sun, Nov 22, 2015, 5:32 PM UTC

Tinyyy wrote: post #42

percept wrote: post #40

I made it my new HN topcolor--not bad.

How much karma do you need to customise it?

https://news.ycombinator.com/item?id=438936

If that's correct, you're close(r).

Re: Non-photo blue

#44

Post by blt » Mon, Nov 23, 2015, 5:33 PM UTC

stan_rogers wrote: post #39

blt wrote: post #23

Earlier quoted context omitted.

The magic word here is "orthochromatic". Orthochromatic photo emulsions (the light-sensitive part of film or photo paper) are only sensitive to short wavelengths of light. The first photo emulsions were all orthochromatic, which makes skin look weird. Later we developed Panchromatic film which is equally sensitive to all colors. It replaced ortho in the camera, but ortho continued to be very useful in the darkroom an…

Not necessarily. Orthochromatic ("correct colour"), or ortho , materials were actually improved-spectrum materials that were sensitive well into the yellow-green. Prior to that, film and paper were really only significantly sensitive to blue/ultraviolet or "actinic" light. Getting to panchromatic ("all colours") was indeed significant, but ortho was advanced technology at the time. (And yes, being able to see what yo…

Whoa, didn't know that. Very interesting. Thanks!