Question colors and print jobs

[Geneva Olson]

We are printing graphics for a van. A lot of the graphics are BLACK. Well, there was a solid black piece with the logo on it. Then under it was a rectangular black piece with white lettering inside of the rectangle.
No matter how hard we tried, you could see the differences in the blacks. Both were in RGB 0,0,0, but when it came to print in flexi, the solid black color was in "lab" and the rectangle was in "rgb". The problem is that the passenger side printed without a color change...the black was the same color black. but on the driver side, the blacks were different.
I finally exported the drivers side as a jpeg and it converted everything correctly. Prior to this it was all in a pdf file.

What difference does all of this make? I really want to learn from my mistakes, but I don't know why they happened. It defied my logic. so I figured I would ask the sign gurus.

Thanks,
Geneva

 

[Solventinkjet]

If the logo is a bitmap and the rectangle with white lettering is vector, your RIP might be setup to render them differently. It's pretty common that RIPs set the rendering intents to two different methods for vector and bitmap.

 

[Geneva Olson]

If the logo is a bitmap and the rectangle with white lettering is vector, your RIP might be setup to render them differently. It's pretty common that RIPs set the rendering intents to two different methods for vector and bitmap.

So, when I converted it all to jpeg it all saw it the same?

 

[Solventinkjet]

So, when I converted it all to jpeg it all saw it the same?

Exactly. If you go in and change the rendering intents to the same method, you can keep your vector objects which is how I prefer to do it but a lot of guys rasterize everything.

 

[Geneva Olson]

Exactly. If you go in and change the rendering intents to the same method, you can keep your vector objects which is how I prefer to do it but a lot of guys rasterize everything.

good to know. thank you

 

[Zendavor Signs]

We are printing graphics for a van. A lot of the graphics are BLACK. Well, there was a solid black piece with the logo on it. Then under it was a rectangular black piece with white lettering inside of the rectangle.
No matter how hard we tried, you could see the differences in the blacks. Both were in RGB 0,0,0, but when it came to print in flexi, the solid black color was in "lab" and the rectangle was in "rgb". The problem is that the passenger side printed without a color change...the black was the same color black. but on the driver side, the blacks were different.
I finally exported the drivers side as a jpeg and it converted everything correctly. Prior to this it was all in a pdf file.

What difference does all of this make? I really want to learn from my mistakes, but I don't know why they happened. It defied my logic. so I figured I would ask the sign gurus.

Thanks,
Geneva

I would recommend you change the Lab color and RGB color to the EXACT same color. Little differences like that can interpret slightly differently and not match side-by-side. We had something silly like this come up just this last week.....and we had to reprint the job.

 

[Geneva Olson]

I would recommend you change the Lab color and RGB color to the EXACT same color. Little differences like that can interpret slightly differently and not match side-by-side. We had something silly like this come up just this last week.....and we had to reprint the job.

It was crazy. The artwork was done in Corel and our graphic artist literally took the passenger side and copied and pasted it and reversed it. Then put the graphics on top. The passenger side colors matched and they were the exact same colors. But when we printed the other side, it didnt match. I'm really confused where the "lab" colors came from because we never used "lab".