HI all,
Theres an image which i used on the website, which now needs to be in CMYK print version.
(see attached)
What i did before was just change the hue/saturation of the photo in fireworks to kinda match the blue behind it.
Can anyone let me know the steps to colorise this photo again for CMYK print in Photoshop?
(to a specific CMYK colour that ive chosen in CMYK book? - it looks different on screen)
You can’t use Fireworks for that as it was created for screen… you need to use a program that can control both RGB and CMYK modes such as Photoshop.
Most of the time, you will work on RBG mode as there are some filters that will not available in any other mode. When the image is ready, then you will change the mode to CMYK and Photoshop will do the conversion.
Things that you need to be aware of is the dot gain. Dark colors tend to be darker when printed. How much? it really depends on the printer you will be using but around 10-20% darker than how they look on the screen.
Light areas are, most of the time, corrected automatically by Photoshop. Anyway, you may have to do a final adjustment of levels or curves to get it right.
It also helps a lot to use a monitor that’s calibrated to use that particular printer. If your monitor is calibrated, the colors in your screen will be more similar if not exact to what it will be printed. If it isn’t calibrated, it is always a risk (although not all printers give you the details to calibrate your monitor so that your colors look like that printer will print)
At the end of the day, you’ll always need a proof of color to know if it will look OK (if you get it wrong, you may need more than one and it doesn’t come cheap… although it is always better than printing 2000 leaflets and realize that your blue looks yellow :D)
If you’re sure which shade of blue you want and you have a color library, you can always base it on that and tell Photoshop to use that particular shade (in the window to choose a color, there’s a button to access the color library, use the name of the library and the number of the color, as an example, Pantone Solid Matte 292 M us a shade of light blue)
thanks molana.
Well the way i was going to do it was first find CMYK colour from book to match the background blue. Then get a proof printed to check its the right one.
Then I would colorize the photo to that specific CMYK colour.
Problem that i was having is how do you colorize a photo specific to a certain CMYK colour?
Say your CMYK colour is C50 m5 y10 k0.
and then what?
Would you first go image > mode CMYK and then create a rectangle in another layer with your exact CMYK colour (color palette right side - CMYK slider selected/)
and then try match it up?
it seems to me you are trying to match a color like if it were a spot ink. not such a good idea.
#1. doing it by eye= risky.
#2 doing it by eye dropper ( which is where I assume you are getting your RGB/ CYMK break down) is hit miss. Why? because the eye dropper samples ONE pixel ( or the average of a small area of pixels) depending. Still its never going to be an exact match
#3. Then there is the monitor calibration issue.
Sometimes, if you are going to a high end print place, or a news paper the pre-press people can calibrate the image so that it matches the color. keep in mind if you sent the image to a second press they too would need to calibrate it as well. What I am saying is if you are REALLY concerned about color accuracy you NEED to work with your printer people.
There IS one thing you can do in for this particular image , maybe. I may be off base here, but since the image seems rather monocrome you may be able to desaturate it ( turn it to gray scale), switch to CMYK mode and then do an overlay of the EXACT color you want.
hope that helps
I think I misunderstood the question. I think that they way I would do it is to desaturate the image by using an adjustment layer (I would never go to Image > Adjustmets because then I’d be touching the original directly and I like to have my original… original, if you know what I mean)
This is my method… Remember! I always use adjustment layers and not the commands under the Image > Adjustments menu!
The way I would do it is (in RGB mode):
I’d go to color selection and write the numbers of the shade of blue I want in the CMYK fields… to get the Hue, Saturation and Brightness values
to desaturate the photo: I would use the Channel Mixer Adjustment layer and click on “Monocrome” at the bottom so I get the gray channel. Then I would change the values of the RGB sliders to control contrast and light… roughly, the 3 values should add up to 100 (not exactly 100 but roughly). Try with the pre-adjustments in the combo at the top… some of them work great.
Then I would add a hue/saturation layer and click “colorize”. I would use the Hue and Saturation values I got before. I may change the bleding mode of this layer from “normal” to “color” so I don’t change the light. I may play with the brightness value.
If necessary, I would add a levels/curves layers (pick your favourite) to increase contrast.
Then change the mode to CMYK and final adjustments
Another possibility, if you are really a fan of Hue/saturation
Use a Hue/Saturation adjustment layer, and in the drop-down menu at the top, choose red.
Put saturation to the very left so reds will go to grey… change contrast by adjusting the luminosity. Then, go back to the drop-down menu at the top and this time choose Yellow and repeat… and so on for every single color
At the end you’ll have a gray scale image.
Create an empty transparent layer over the adjustment layer. Go to Color Selector and write the numbers of your shade of blue in the CMYK fields.
Use the bucket to color the transparent layer. Then change its blending mode to “overlay” or, if you want a more dramatic effect, “color”
Change mode to CMYK and use levels/curves to do the final adjustments.
hi Molana,
Thanks your being a great help - im going through your #1 suggestion first.
I was doing ok in the steps, except in the end.
I had 2 adjustment layers - 1 hue/saturation 1 channelmixer
I then went image > mode > CMYK
Popup came up saying it had to discard adjustment layer.
I clicked ok and image changed to black/grey
How else should i be doing this?
Be specific as im a newbie in photoshop, usually use fireworks(web)!
Only learnt about adjustment layers now;-)
#2 suggestion worked better!
Except I couldnt find “change contrast by luminosity” anywhere
and same problem at end when changing to CMYK.
What if i do image > mode > cmyk before all these steps?
It will ask you to discard the layer, but you don’t have to. You can either accept, cancel or combine the layers… choose the last option. You will get the image in just one layer, but all the changes will be done and you can save it with another name.
Another option is that you change to CMYK mode from the very beggining, as you suggest. The reason I don’t do it is because some filters only work in RGB mode, but if you’re not going to use filters, you should be fine.
Except I couldnt find “change contrast by luminosity” anywhere
This is because I didn’t explain myself very well and I use Photoshop in Spanish, so you need to use a bit of imagination when I translate.
In the hue/saturation channel, it is the last slider… it may be called brightness, though. Not sure.
If you move it to the right, you’ll be increasing the light/brightness of the color you’re affecting at that moment. So, if you’re desaturating the reds and move the slider to the right, all the reds in the photo will look lighter.
I hope my explanation is a bit better.
I used this option to be in CMYK print version.
thanks all, thanks molona 