PDA

View Full Version : General guidlines for print work?



Etch
02-14-2008, 10:22 PM
Been getting some stuff together for an art competition next month and decided to got get some tests printed off as this will be my first official entry into anything.

Anywho printed off one image that was 555x1024 and it was printed off at 11x17. This would give it a resolution somewhere in the ballpark of 60pi/in right? I'm not exactly sure since the image was such an irregular size uneven borders had to be added to make it fit the paper. The quality wasn't really what I was hoping for but all I have to do to fix it is re-render the scene and multiply the dimensions by say 300? So if I wanted a 1 inch border all around the image I would need to render it at 3000x4800, right?

My other question was about how different the colors were between my screen and another print I did. On my screen the colors were much more vibrant an bright, but in the print you can barely make them out. Is there a way to fix something like that in post or am I going to have to actually lighten the colors in my original scene? If it helps at all I have a 19" lcd acer monitor and an asus eax1600pro graphics card.

Thanks for the help.

theo
02-15-2008, 07:42 AM
My other question was about how different the colors were between my screen and another print I did.

Mixing colored lights is additive mixing (your screen).

Mixing pigment is subtractive mixing (your printer).

You really need to educate yourself on these differences. A rudimentary study in color science is amazingly helpful.

The fact is your printer is limited to reproducing colors only available within its ink-based gamut. A vast range of colors available to the LCD monitor are not reproducible by a printer.

Imagine yourself painting what you see on screen with only three primary pigments and possibly black (if your printer supports this).

The next step will be an investigation into the various color spaces, the most important of which will be RGB and CMYK. If you are printing in-house or sending the file out the color space of the printed world is CMYK. Practically all RGB files are ripped to CMYK even if the printer (company or machine) processes the files as RGB.

I can tell you from years of experience of successfully producing a wide range of full color printing material ranging from massive murals to thousands of pieces for corp. id./advertising projects that you can approximate on-screen CMYK ink values to their real-world counterparts. I have never used a screen calibrator, even on projects where I was paid many thousands of dollars.

One of the best investments you will make on image correction for printing is to purchase a book called Professional Photoshop (fifth edition) by Dan Margulis. This is a very deep tome but if you are interested in exposing your nose to a serious grinding you will find everything you need in this one book.

safetyman
02-16-2008, 08:41 AM
Theo seems to be the expert color guru here, so heed his advice on the color aspect. LCD monitors are many many times brighter than what gets printed. Also, you have to consider the type of paper you're printing on. A 24 lb stock will absorb more ink, therefore muting the colors. A 28lb high brightness paper will yeild better results.

As far as the resolution -- what I do is multiply the physical dimensions of the final art by the resolution you're going for. So, for example, if you wanted an 11x17 image at 300 dpi you would multipy 11x300 and 17x300 to get your pixel dimension (as you have done). Usually, when you bring that into Photoshop, it gets "converted" to 72-dpi, but it's still the same pixel dimensions, so you'll have to reset it in the image size dialog (not sure how the Mac does this).

Etch
02-16-2008, 01:02 PM
Cool cool, so basically I need to start confining myself to colors that are designed for printing. That makes sense. Is there any way that I can confine myself to those colors while using Lightwave?

Also you guys have talked a lot about using photoshop which I've had enough experience with to know what you're talking about but all I currently have access to is The Gimp (http://www.gimp.org/). Do you think the programs are similar enough that the concepts would apply evenly to them?

Thanks again for the help, these boards are always such a great source of info.

safetyman
02-16-2008, 05:47 PM
I don't really know anything about Gimp, but I've heard that it's a great program, and free to boot! However, in the print world, Photoshop is the de facto standard and most printers prefer to work with images created with it (i.e. .eps files).

Matt
02-16-2008, 07:02 PM
Anywho printed off one image that was 555x1024 and it was printed off at 11x17. This would give it a resolution somewhere in the ballpark of 60pi/in right? I'm not exactly sure since the image was such an irregular size uneven borders had to be added to make it fit the paper. The quality wasn't really what I was hoping for but all I have to do to fix it is re-render the scene and multiply the dimensions by say 300? So if I wanted a 1 inch border all around the image I would need to render it at 3000x4800, right?


This plugin my help you out:

DPI Camera v1.2
http://www.newtek.com/forums/showthread.php?t=79515

tribbles
02-16-2008, 07:58 PM
I've used a program called RGB2CMYK which takes an uncompressed RGB TIFF, and does a /very/ good job of converting it to CMYK (well, it's done a very good job on everything I've thrown at it).

http://www.smokingun.co.uk/sg/freestuff.htm

Problem is that it is uncompressed, so for print jobs, that's pretty large...

Maxx
02-16-2008, 09:42 PM
In Photoshop (no idea about GIMP, sorry, but I assume there's a similar function somewhere. If not, check out tribbles' link), you can preview the RGB image in CMYK colorspace. Also, you can obviously convert from one to the other. So it becomes less of an issue of attempting to deal with CMYK colorspace in Lightwave than simply knowing that when you're looking at your render in the image previewer, certain shades are going to be slightly different and being able to judge what it'll probably look like after the shift. You can then take the render into your image processing program and convert to CMYK, and then go back to LW to re-render if necessary :D .

I've actually done a couple of press printed full-line product catalogs in which every product shot was rendered in LW, and not had a problem with the color transfer from RBG to CMYK. You just have to play with both colorspaces to get an idea of what to expect.

And - in my experience - don't send RGB files to a printing company. They hate that.

JonW
02-17-2008, 12:11 AM
One doesn’t need all the printing knowledge but some understanding will allow you to produce reasonable results.

You do need to get the correct results at each step of the process, or you will have an accumulation of errors, wasted time and expense.

You may even want to get your eyes calibrated. I’m about 1% weak in the yellow/green part of the spectrum when I last was tested. 10% of males have some degree of colour blindness.


The following link has a lot of good stuff, easy to follow.

http://www.cambridgeincolour.com/

Another useful link.
Just doing some basics will help!

http://www.creativepro.com/story/feature/11791.html