# inverted white on black?



## 4taylormadetees (Jan 9, 2009)

how do you make a regular black image ready to print with white on black? do you just invert and then make a boundry shape like image and powerclip?


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## TYGERON (Apr 26, 2009)

Yep. That's about it. Don't necessarily have to powerclip though.


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## 4taylormadetees (Jan 9, 2009)

when i invert, it makes the background black.thats why i powerclip.i use corel draw


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## TYGERON (Apr 26, 2009)

You talking a vectored image or bitmap?


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## 4taylormadetees (Jan 9, 2009)

need to know both ways?i was using a bitmap grayscale image and converted to halftone bitmap


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## tpitman (Jul 30, 2007)

Personally, I have found that instead of inverting an image and printing it with white ink, I was more successful in opening the file in Photoshop and making a spot color white ink channel with the image, then adjusting levels to improve the image. It gives you a better idea of how it'll look before you run your film as opposed to just inverting the file and generating film. I had a job that I tried inverting and it looked like hell on press. Did the conversion to a white spot color channel, made some adjustments, and it printed great.

Pitman Graphics
T-Shirt Printing by Pitman Graphics


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## 211chucky (Mar 23, 2010)

tpitman said:


> Personally, I have found that instead of inverting an image and printing it with white ink, I was more successful in opening the file in Photoshop and making a spot color white ink channel with the image, then adjusting levels to improve the image. It gives you a better idea of how it'll look before you run your film as opposed to just inverting the file and generating film. I had a job that I tried inverting and it looked like hell on press. Did the conversion to a white spot color channel, made some adjustments, and it printed great.
> 
> Pitman Graphics
> T-Shirt Printing by Pitman Graphics


i was hoping you could illabarate on this method you are talking about. i have seen it done but cant figure out how to do it. i have seen several shirts that look really good just white ink on a black shirt which is what i want to do but am having a hard time figuring it out. help please??


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## tpitman (Jul 30, 2007)

You'll need to make a mask or an alpha channel that you can use to select the subject and drop out the parts you don't want to print, in this case a white background. If it's a square photo and you want to include everything in it then you don't need to do this.
Change to mode/grayscale, then mode/multichannel. You'll have a "black" channel where the "gray" channel was, plus your "mask" or alpha channel. Create a new spot color channel and name it "black shirt" or whatever shirt color you want. Make sure the color in the box is 100% black, or just pick the color in the lower left of the picker. Move this channel to the top of the channels palette. Take your "black" channel, double-click on it and make it a spot-color channel named "white ink", making sure the color picker is white at 100%. Invert the channel, apply the mask or alpha channel, control or command "i" to select the background and hit delete. Then, select the white ink channel and adjust the levels to whatever looks good to you. You'll notice that the 4th photo of white ink is pretty much what you can expect if you just invert a grayscale photo, run film, and burn your screen. It's hard (for me, anyway) to look at a negative image and adjust the tones to print in reverse, which is why I set the job up as white ink on a black shirt in multichannel mode.
These pics appear in the working order described. The photos are identified at the bottom of each as to what each represents:


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## 4taylormadetees (Jan 9, 2009)

i use corel draw x4 only right now?


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## tpitman (Jul 30, 2007)

You could probably (maybe) do the same in Corel PhotoPaint which comes with CorelDRAW. Not sure, though. I've never used it. CorelDRAW is pretty much for vector graphics, much like Adobe Illustrator.


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## 211chucky (Mar 23, 2010)

tpitman said:


> You'll need to make a mask or an alpha channel that you can use to select the subject and drop out the parts you don't want to print, in this case a white background. If it's a square photo and you want to include everything in it then you don't need to do this.
> Change to mode/grayscale, then mode/multichannel. You'll have a "black" channel where the "gray" channel was, plus your "mask" or alpha channel. Create a new spot color channel and name it "black shirt" or whatever shirt color you want. Make sure the color in the box is 100% black, or just pick the color in the lower left of the picker. Move this channel to the top of the channels palette. Take your "black" channel, double-click on it and make it a spot-color channel named "white ink", making sure the color picker is white at 100%. Invert the channel, apply the mask or alpha channel, control or command "i" to select the background and hit delete. Then, select the white ink channel and adjust the levels to whatever looks good to you. You'll notice that the 4th photo of white ink is pretty much what you can expect if you just invert a grayscale photo, run film, and burn your screen. It's hard (for me, anyway) to look at a negative image and adjust the tones to print in reverse, which is why I set the job up as white ink on a black shirt in multichannel mode.
> These pics appear in the working order described. The photos are identified at the bottom of each as to what each represents:


this is the best tutorial i have ever seen on this subject but i cant follow you because i dont know how to do all the things you are doing in photoshop. is there anyway that you can break down the steps of how you do each one. i cant figure out how to do the alpha channel, spot color channel, any of it. it would really help me alot if you could help me out on this.


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## ScreenFoo (Aug 9, 2011)

This isn't really what I do day in and day out, but assuming your art has a good black background I've had excellent luck (with photo-paint or photoshop) going to either the HSV or LAB color models, and inverting and curving the lightness/value channel. Inversion should make the perfect black background perfect white, and then you're free to modify the values based on your screen luck.
It seems like as long as you increase contrast you will compensate for dot gain at the low end, and filling in on the high end in your curve.
Not to say you can't do way better, but I get decent inversion prints with basically two steps of manipulation.


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## 211chucky (Mar 23, 2010)

ScreenFoo said:


> This isn't really what I do day in and day out, but assuming your art has a good black background I've had excellent luck (with photo-paint or photoshop) going to either the HSV or LAB color models, and inverting and curving the lightness/value channel. Inversion should make the perfect black background perfect white, and then you're free to modify the values based on your screen luck.
> It seems like as long as you increase contrast you will compensate for dot gain at the low end, and filling in on the high end in your curve.
> Not to say you can't do way better, but I get decent inversion prints with basically two steps of manipulation.


it this point i will try anything.thank you for your response.


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## Lucky7Matt (Oct 7, 2011)

I don't know what I am doing wrong but I just cant get this right


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