Weird colours?

"honest joe" wrote in
news:dh0nip$d65$:

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer examination, it was only knitted jerseys and cardigans that came out purple. The regular sweat-shirt type jerseys were perfect. What do ya think?

Try using another print shop!

—
f=Ma well, nearly…

honest joe wrote:

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer examination, it was only knitted jerseys and cardigans that came out purple. The regular sweat-shirt type jerseys were perfect. What do ya think?

Can’t you limeys get it right! It’s colors NOT colours!

PS. Want a good deal on some used English WW2 tanks? Great shape, except all the reverse gears are worn out. FM…

"honest joe" wrote in message

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer

examination,

it was only knitted jerseys and cardigans that came out purple. The

regular

sweat-shirt type jerseys were perfect. What do ya think?

Something I’ve noticed may be part of it…
The way self-service photo developers found in mass merchants resize the photo is not accurate. Instead of resampling the image, pixels are simply ignored. Perhaps mostly pixels of the blue color was lost as well.

First time I saw this effect was a strong moir

In article <dh0nip$d65$>,
"honest joe" wrote:

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer examination, it was only knitted jerseys and cardigans that came out purple.

Yes, that sounds about right.

Your digital camera shoots pictures in RGB; it simulates a full range of color by combining red, green, and blue light.

A printout, of any sort, can not use RGB; prints use CMYK (cyan, magenta, yellow, and black inks) if they are made on an inkjet or color laser printer, and CMY (cyan, magenta, and yellow) if they are made on photographic paper.

There are many colors you can get in RGB that are not possible in CMYK or CMY. In particular, vivid blues can not be reproduced in CMYK or CMY; they tend to get flat, lose saturation, and turn purple.

If you take your digital image in Photoshop and convert it to CMYK, you’ll probably see the same thing happen on your screen–the bright, saturated blues will turn flat and purple.

You can fix this problem; Photoshop offers many powerful color correction commands, if you learn how to use them. If you use the Selective Color command to decrease the amount of magenta in your blues, the blues will not turn purple when you have your prints made.

—
Art, photography, shareware, polyamory, literature, kink: all at http://www.xeromag.com/franklin.html

In article ,
says…

In article <dh0nip$d65$>,
"honest joe" wrote:

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer

examination,

it was only knitted jerseys and cardigans that came out purple.

Yes, that sounds about right.

Your digital camera shoots pictures in RGB; it simulates a full range of color by combining red, green, and blue light.

A printout, of any sort, can not use RGB; prints use CMYK (cyan, magenta, yellow, and black inks) if they are made on an inkjet or color laser printer, and CMY (cyan, magenta, and yellow) if they are made on photographic paper.

There are many colors you can get in RGB that are not possible in CMYK or CMY. In particular, vivid blues can not be reproduced in CMYK or CMY; they tend to get flat, lose saturation, and turn purple.
If you take your digital image in Photoshop and convert it to CMYK, you’ll probably see the same thing happen on your screen–the bright, saturated blues will turn flat and purple.

You can fix this problem; Photoshop offers many powerful color correction commands, if you learn how to use them. If you use the Selective Color command to decrease the amount of magenta in your blues, the blues will not turn purple when you have your prints made.
—
Art, photography, shareware, polyamory, literature, kink: all at http://www.xeromag.com/franklin.html

Aside from the, often great, differences in the colo(u)r gamut, between RGB & CMYK, many fabrics have "brighteners" in them, and flouresce, adding quite a bit of UV, that our eyes do not see. Bright whites often go rather blue. Though we are talking digital here, some films are more sensitive to UV, than others. I THINK that digital capture might be a bit less sensitive, but you probably have some UV interaction here, as well. Especially, when you consider that the color casts happen with different fabrics, that appear to be the same color to our eyes. The difference that you perceive on the monitor might well be an inability to define these color differences, but when printed, some of this may well creep in. Often, the addition of a UV filter (definitely in film, and maybe in digital) will block some, or all of the excess UV. If one wants perfect color match, then test shooting of these fabrics is necessary.

Hunt

"honest joe" wrote in message

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer examination, it was only knitted jerseys and cardigans that came out purple. The regular sweat-shirt type jerseys were perfect. What do ya think?

This sounds interesting.

My guess is that the sweaters were darker than the sweats, and the printer is adding red to the shadows. The color zoo has only one guest right now, also plagued by a print profile with too much red:
http://www.curvemeister.com/tutorials/ColorZoo/index.htm

Can you post the image or email a copy to mike at curvemeister.com? If I decide it’s of general interest, I’ll consider adding it to the color zoo. —
Mike Russell
www.curvemeister.com

"

OR it might be the way the light is reflecting off the material. Cotton reflects light differantly than silk, nylon, rayon.
"honest joe" wrote in message

Anybody got any idea about this. I took digital shots of children starting school last week. They were perfect on my PC. When I got them processed, some of the uniforms came out purple instead of blue! On closer

examination,

it was only knitted jerseys and cardigans that came out purple. The

regular

sweat-shirt type jerseys were perfect. What do ya think?