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Paul Corfield
05-29-2004, 06:15 AM
Here's a quick guide on how to separate CMYK on the computer. The images can then be printed out as a guide during the painting. I use Adobe Photoshop 5 so if you use something else the methods may be slightly different. See photos below for how the images should look in their black plus one color state and I've also included the full color photo. The photo is of my 16 month old boy.

Step 1 - Open up a photo in your software.

Step 2 - Convert the image to cmyk. To do this in photoshop click on the tabs marked Image/Mode/CMYK

Step 3 - In photoshop on the right hand side of the screen there is a box with three tabs on that are named 'Layers' 'Channels' 'Paths'. You need to click on the one named 'Channels'.

Step 4 - Click in the box that says 'Black'. You should be left with just the black channel turned on and this box should be colored blue with all the others white. At this point the photo can be printed in it's black and white state.

Step 5 - Now it gets a bit tricky. Decide which order you are going to paint in. Black will be first because it's easy to paint a detailed painting in black and white and then tint it with the other three colors. In the channels box click on one of the other colors that you don't want to paint. At the bottom of the channles box there is a small dustbin icon. Click on this to delete the channel. Then do the same with one of the other colors that you don't want to paint. This leaves you with just black and one color left turned on. print this image.

Step 6 - Above the channels box is another box that has two tabs - 'History' and 'Actions'. The history box allows you to backtrack the steps we have just done so that we can select different colors. Scroll down the list in the history box and delete the two called 'Delete Channel' using the small dustbin icon. In the channels box you will see all your colors have returned. At this point you have the option of deleting two of the other colors and keeping black plus a new color or you can keep black plus the color you kept last time and then add a new color to the list so this time you have three colors kept and one deleted. This is probably easier as you can see how the painting should look once the new color is applied to the last two. It's easier in practice than it may appear here. If you like you can print both options and then you have the complete guide of how much color to spray and also how it should look.

Step 7 - Go back to the history box and delete the steps as before to backtrack as we did in step 6. This time all the colors will be left turned on and you just print the photo like you would a normal photo. Also you can print just black and the last color as above so you can see by how much and where to paint it.

Once the black and white image is painted the other colors will be fairly flat graduations of color. For the black and white painting I prefer to mix my initial black from the cyan, magenta and yellow mix. I find the airbrush is much less prone to clogging with this mixture than if you use just straight black from the bottle. I find straight black is very prone to tip dry.

That's about it. It sound complicated but in practice it's very easy. :rolleyes: :)

Paul.

pr1130
05-29-2004, 10:46 AM
Paul, do you know of any software available that will convert RGB to it's CMYK counterpart and then tell you what percentage of of each (cyan, magenta etc) are required to mix it?

Peter

Paul Corfield
05-29-2004, 11:34 AM
Yes, you can do that in Adobe Photoshop.

Open up a photo as per normal. Then convert it to CMYK. Then pick the eyedropper tool and wherever you click on the photo with the eyedropper tool it will tell you on the right hand side of the screen in the box that has the color tab what the percentages are of CMYK.

I also have Paint Shop Pro 5 but you can only work in RGB percentages in that.

Paul.

Penny220
05-29-2004, 05:41 PM
I really appreciate this post. Although I have photoshop I don't use it. I use Paint Shop Pro. There is something you can do to convert to CMYK in PSP I finally figured it out today. Unfortunately, it doesn't work the way we would like it too. It's in the print dialog window, it will print 4 pages of the photo but it prints them in b&w, they are seperated but not in color, just grey tones. Since I have been trying to do this for a few years now, I'm going to re-install photoshop today and try this.

Thanks again

Paul Corfield
05-29-2004, 08:42 PM
Photoshop will also try and print the image in black and white unless you do it exactly the way I have outlined above. Photoshop is way more advanced than PSP. PSP will split an image into CMYK but even then PSP treats it like a RYB image when you use the eyedropper tool which is wrong. I don't have the latest PSP. Mine is version 5 so maybe it's more up to date now. I have a version of Corel Photopaint too but I can't get it to load anymore.

Paul.

Penny220
05-29-2004, 09:00 PM
I'm SO glad you mentioned Photo Paint. As it turns out I don't have photo shop, what I have is photo paint. I can easily convert to CMYK and split channels but the channels show up in B&W, is there a solution?

I'm behind on PSP versions too, I have version 6, one of these days I will download the trial for the new one, they still give the free 30 day trial, I think they are up to 8 right now. I prefer PSP because it's so much easier to work with and since it's what I learned on I think I will always be more comfortable with it.

If this can't be done with Photo Paint, can it be done in illustrator? I have version 8 on that, another fine program I hate and don't even bother to install anymore. :(

Paul Corfield
05-30-2004, 06:39 AM
As I can't get my Photopaint to install I can't help on that one I'm afraid. It should be able to do it though and it's set up similar to Photoshop so try the method I laid out above. Another method is this. If you can get the image to appear in color on the screen but it prints out in black and white you can use another type of software to do a screen grab. This creates a jpeg of whatever you have on the screen at the time and this can be cropped down just to show the photo you want to print.

Paint Shop Pro has this function to let you capture your desktop or just a small section of it.

Paul.

pr1130
05-30-2004, 08:16 AM
Photoshop has a price tag of around 1000$ here so thats quite out the question for me.

Penny, PSP version 8 is no better with CMYK than any of their previous releases.

As far as the eyedropper tool goes. I downloaded this nifty little tool yesterday at the link below. It's call "visual color picker" (freeware).

seems to work pretty good.

http://www.linxexplorer.com/colorpicker.html

Peter

AlpineAirbrush
05-30-2004, 04:14 PM
Paul, thank you so much for taking the time to post this, it's very helpful !

Thanks for that link Peter ! That's a great little tool to keep on the desktop. :cool: If you have your heart set on Photoshop, yoou might look for it on EBAY, you can pick it up for 1/2 price or less. Just be sure to get the full version.

Also, you can usually download free trial versions of these different softwares to try for a period of time to see what works for what you want to do.

pr1130
05-30-2004, 04:54 PM
Thanks Kevin! I have used the trial versions of photoshop and do like it but it's still a bit too much for me to justify. I have PS Elements which I find does just about everything I have needed up to this point. Maybe down the road my needs will change (along with my income LOL).

Thanks for the tip.

Peter

ProfessorGreibowitz
05-31-2004, 02:37 AM
I'm confused. Each color pic of CYM has black in it too. Why are pics 2,3 and 4 containing black as well as the color? I thought it'd be a sheet of black, then cyan, yellow and magenta. Do you get black in the colors also or what is happening?



thanks,
Tim

Paul Corfield
05-31-2004, 03:04 AM
I'm confused. Each color pic of CYM has black in it too. Why are pics 2,3 and 4 containing black as well as the color? I thought it'd be a sheet of black, then cyan, yellow and magenta. Do you get black in the colors also or what is happening?



thanks,
Tim

Hi Tim,
The reason being is that you would paint the black and white image first and all subsequent layers will be painted over the black and that's why I have shown them that way in the photos. Generally what I have found when using the eyedropper tool is that the CMY percentages in the dark areas are around 40% to 50% each. Also in any software I have used, if you single out just one of the color layers the computer will only show it in grayscale and not color. It only shows it in color if you combine it with the black layer. You can work from the grayscale image. In grayscale, the darker gray is where you would put more of the color. It all depends on whether you are happy working that way and whether you can convert a grayscale photo into the actaul percentage of color on the painting.

Paul.

Paul Corfield
05-31-2004, 03:19 AM
I found the results with the Visual Color Picker 2.0 software vary a lot compared to the results with the Photoshop eyedropper tool.

Paul.

ProfessorGreibowitz
05-31-2004, 12:58 PM
Okay, Paul. I'll try this sometime.



Tim

freshcolor
07-26-2007, 09:41 PM
Paul:

How do you rpoject digital photos on the wall?

regards,
Ruth Ann Greenberg (new member)

ProfessorGreibowitz
07-26-2007, 10:19 PM
wow! Talk about reviving an old thread...

You can print the digital photo on paper and use an opaque projector or print on transparency "paper" and use an overhead projector or if you have a digital projector, connect to your computer and project it directly from the computer. I have an overhead I use.


tim