Large format print resolution

[ATTTR]

Total large format printing newbie here who has been thrown headfirst into the raging fire.

I recently started a new position working with large format printing.
So far it's only for vehicle graphics and wraps, but the owner would like to expand to posters, banners, billboards, expo booths, etc...

As a graphic designer by trade, I've only worked on small printing projects. Letterhead, logos, ads, books, booklets, brochures, you get the picture.

This is my first foray into large format and I am way out of my element. The person I replaced put in their notice and I had only 4 hours to train with him on how this all works. From setting up the files to printing the materials. The thing is, he told me I should be doing everything in 300 dpi. If anyone has done a 40' or more trailer wrap, can you imagine the size of the file? How long it takes to save or open or just plain do anything with. As time went on, it seems what this person told me about a lot of things was incorrect just to sabotage me (he regretted turning in his notice, but he really burned his bridge here and he wasn't allowed to stay.)

So, can anyone help me out with some nice clean guidelines regarding print resolution of files?
Should I really be doing everything in 300 dpi or can I drop that to 150? I've been trying to do research but there are so many conflicting sites and bits of information I am completely lost. I understand dpi vs line of sight distance... but not clear on the correlation to dpi.


Thanks!

 

[SIGNTIME]

i think you mean ppi for designing in... for large wraps if the file in pixels we set a 300ppi and have the file drawn in 1/10th scale and let our rip software handle scaling, idk what printer or rip you use but that works for us and others will do it differentally... when printing large wraps we will print at 360x720 dpi or 540x720 depending on our work load... for smaller signs and items that will be viewed close we print at 720x1440dpi

 

[idsignsil]

Design at 720ppi at 1/10th scale. Then when you rip, scale it to 1000 percent and your print will be at 72dpi, the minimal acceptable resolution for printing a wrap so that you get acceptable results, and acceptable performance when designing and printing it.

 

[ATTTR]

Yes, PPI - SORRY!

I was going through some old files here just a few moments ago and I found a leaflet that it looks like my predecessors would send to clients.


So I guess I don't even need to be doing files in CMYK...?
Sorry I seem like such a freak, this is all just so new to me, and I don't even know where to begin to learn what I need to know.
There is no one else here that can train me, I am doing it all on the fly.

@signtime - I have a Mimaki JV3130spII and use Onyx software.

 

[SIGNTIME]

cmyk vs rgb has been debated alot on here and from what i have read rgb is acctually prefered by most ... my best advice for you would be to cherish the search bar on here and talk to your boss about maybe having the dealer come and give you a little training after you have worked with the printer for a few weeks and during those few weeks write down questions and search and ask for answer here... remember search first one other thing read the manually for the printer to learn about maintenance and adjustment and the like ... its probably gonna get overwhelming but youll get it

 

[d fleming]

Mamma said CMYK is the devil.

 

[MrSalumi]

+1, or tell your boss that you are going to need more money for all the material you plan on wasting.. My guess is that they will spring for the training

talk to your boss about maybe having the dealer come and give you a little training...

 

[rfulford]

Looking at the leaflet, it looks like the standard was 100 ppi RGB color with a 72ppi minimum. This sounds pretty standard. I personally shoot for 130-150 ppi on our printers since I can see a bit of pixelation on anything lower than 130 ppi.

 

[bob]

The unaided human eye and the brain to which it's connected has a hard time differentiating 1 part in 130. That why most half-tone screens were 130 dpi.

When you print you want to print at a resolution 4x the image resolution. Or thereabouts. Print 150 ppi images at 720^2 gives you >2^16 possible color combinations for each image pixel. That is sufficient. Unless you like to use lots of ink there's no reason whatsoever to print at 1440. There's also little reason to drop below 720. The miniscule amount of time and ink saved is seldom, if ever, worth it.

CMYK vice RGB? For bitmaps, always RGB with the rendering intent set to 'Perceptual'. For vector stuff and especially gradients most people use CMYK but it really doesn't matter. With all of your other rendering intents set to 'No Color Correction' or, failing that, 'Saturation' your rip will sort it out far better than any other software you own.

What comes out of the printer is the truth. Once you understand just what your particular tackle will produce you can make it do pretty much whatever you want. Keep your environment variables such as image resolution, printer resolution, and various printer settings, constant and you'll seldom be surprised.

 

[milchad]

I found this on the internet and it might be of some use:

FONTS

Transport Graphics requires that all digital files have fonts converted to paths or outlines. If this is not possible, we have a vast library of fonts and we will attempt to find an adequate substitute for missing fonts but an exact match cannot be guaranteed.
APPROVED SCALES

The mobile advertising industry is unique in the fact that the artwork we produce is larger than any other industry. In order to build these files, Transport Graphics uses specific “scales”, which allow us to build the artwork at a percentage of the actual size. For example, the maximum working area in Adobe Illustrator is just over 227” and a 53 ft. trailer is 636” long. Obviously, the artwork cannot be built at actual size. For projects like this, we use one of the following scales:
SCALE PERCENTAGE

SCALE	PERCENTAGE	CONVERSION	EXAMPLE	MIN. IMAGE RESOLUTION**
1:1 SCALE	actual size	1″ = 1″	636.00″ = 636.00″	72 ppi
1:2 SCALE	files built at 50%	1″ = 2″	318.00″ = 636.00″ at actual size	144 ppi
1:10 SCALE*	files built at 10%	1″ = 10″	63.60″ = 636.00″ at actual size	720 ppi

VECTOR-BASED ARTWORK

A vector-based graphic is a graphic that uses anchor points and paths to form shapes as opposed to pixels. The advantage of a vector-based graphic is that it can be scaled indefinitely without any loss of quality. Programs that use a vector format include Adobe Illustrator, Macromedia Freehand and CorelDraw.
This file type would be used in the production of signs, banners, or vehicle graphics that are to be cut from solid pieces of material. In some instances, a vector file can be used for digital printing (such as multi-colored decals, complex designs, or large quantities).
When using a vector-based program, files should be built at actual production size or one of the approved scales listed above. Be sure to note the scale of your files on any provided prints as well as in the file itself.
If your file includes placed images, the image must accompany the parent file on your disk.

PROPER RESOLUTION

Images built at the correct resolution will be sharp.
​

Image resolution is the number of pixels per square inch in a given image. Pixels are the tiny dots that determine the color and sharpness of the image. The more pixels, the clearer the image will appear, not enough pixels, the image will look blurry.
Ideally, we use an image resolution of 72 pixels per inch (PPI) at the actual production size for digital printing. Images that are lower than 72 ppi tend to be below our quality standards.
The part that can make this confusing is when you start changing the mathematical size and how the changes effect the resolution.
Lets say that your “original” image is 1″ by 1″ at 100 ppi. This means that this image has 100 pixels in it’s 1 square inch area. If you change the mathematical size to 10″ by 10″, you now have a 100 square inch area. Since the “original” only had 100 pixels, those pixels now have to stretch to cover 10 times the area and the only way this can happen is if they “fuzz”, creating the blurry looking image. The higher the resolution of the ORIGINAL image determines how clear the image will be when the mathematical size is increased.
For correct image resolution

Resampling images that are too small will make them blurry.
​

in scaled files, please review the “Approved Scales” section.
Resampling images that are too small will make them blurry.

 

[ATTTR]

Thanks for all the great advice. It has helped immensely.

@milchad - do you happen to still have the URL for what you posted? I am wondering if the entire site would be a good resource for me.

Thanks to everyone who responded. Very grateful for the assist!

 

[bob]

I...
The part that can make this confusing is when you start changing the mathematical size and how the changes effect the resolution.
Lets say that your “original” image is 1″ by 1″ at 100 ppi. This means that this image has 100 pixels in it’s 1 square inch area...

The mathematical incompetence in the above snippet is stunning. This alone should be sufficient reason to doubt anything else these innumerate dolts might have to say.

 

[John Butto]

The mathematical incompetence in the above snippet is stunning. This alone should be sufficient reason to doubt anything else these innumerate dolts might have to say.

Without a basic knowledge of mathematics and arithmetic. Bob used it as an adjective.
A stupid person. This is a noun.

 

[milchad]

The mathematical incompetence in the above snippet is stunning. This alone should be sufficient reason to doubt anything else these innumerate dolts might have to say.

You're right, that was a major snafu on their part wasn't it? Thanks for pointing that out...

 

[goforit14]

i design on photoshop on resolution of 120 for large format save the file to intended size example 2 ft x 4 ft as a jpeg then open it on flexi sign, on there before i click send i change the printer settings depending on what i need for banners i use the quickest setting to print them fast for other media i print slower 720 x720 i use this on window signs with images of people for example, also make sure you use the profile for the material your using other wise you risk getting some mismatched colors . i only use 300 for business cards or postcards things like that. on large format

good luck just keep trying the settings on the printer. get yourself some free samples from your vinyl manufacturer so that you can play around . print pictures of persons gradients letters until you find a combination of setting that works for your particular printer

 

[PrintItBig]

The mathematical incompetence in the above snippet is stunning. This alone should be sufficient reason to doubt anything else these innumerate dolts might have to say.

Why?

 

[rfulford]

Why?

1 square inch of an image with a resolution of 100 ppi contains 10,000 pixels.