Exhibition Printing Design Help

Printing and Prepress
#1

Hi,

I’m working on a project to design artwork for an exhibition stand. The exhibition stand’s physical structure and construction are already set, so I don’t need to design its shape or layout. My role is solely to create the artwork for the walls, counters, roof banners (where the logo will be placed), etc., following the provided guidelines.

According to the guidelines provided by my client (which they received from the vendor), the final file must be submitted as an editable PDF. Since my design includes product images in certain sections, these images will be part of the PDF. I’m designing in Adobe Illustrator, and I’d like to clarify how images are handled when exporting to PDF—will they be embedded by default, or will they remain linked? Each image is approximately 80 cm x 50 cm in print size. From my understanding, Illustrator typically embeds images when exporting to PDF, but how can I ensure they remain linked instead?

I assume linking is the correct approach because the guidelines state:

  • All artwork must be submitted no larger than 25% scale. Please ensure
    that the dimensions/resolution are still in proportion. E.g 300dpi
  • Any linked files must be supplied.

Second question:
Since the guideline specifies that artwork should be scaled down to 25%, does this mean the resolution must be adjusted proportionally as well?
For example, if the actual artwork size is 200 cm x 150 cm at 300 DPI, should the scaled-down version be 50 cm x 37.5 cm at 1200 DPI to maintain image quality? (I doubt if 1200 dpi is possible to export in illustrator?)

I don’t know if the scale down is a standard practice in exhibition design. This is my first time designing for an exhibition, so any insights would be greatly appreciated. Thanks!

#2

Firstly - Illustrator unless you insert an image as Link and it’s visible in the Links panel then it’s embedded.

Export to PDF is not possible in Illustrator - you save as PDF - and select Illustrator Default and Preseve Illustrator Editing capabilities from the Save AS PDF from Illustrator.

You then can open the PDF in illustrator to make edits -so you won’t need the .ai file as it’s embedded in the PDF file.

Regarding resolution - for large displays 300dpi is not necessary you could be 25% of that at 75 ppi but the higher the better.

Just be mindful of the practical differences between effective resolution when scaling and actual output resolution.

If you’re designing at 25% scale and insert an image at 300 ppi, the output resolution when scaled up to 100% (full size) will be 75 ppi. This will typically be ok for large displays - when viewed from a distance - 300ppi is typically for print of books and magazines and viewing at close range.

When you place an image at 300 ppi in a document designed at 25% scale, it’s effectively four times the size when expanded to 100%.

Since resolution is inversely proportional to scale, when you increase the size to 400%, the resolution is divided by 4 (300 ÷ 4 = 75 ppi).

This means that if you’re designing at 25% scale and need an output resolution of 300 ppi at full size, you should place images at 1200 ppi at 25% scale.

But this is too high for large format display - you can typically go to 150ppi for final output, that would be 600 ppi at 25%

1 Like
#3

Thank you for your insights! The images will be viewed from a relatively close distance—perhaps around 60 cm or less. The exhibition structure features a narrow alley (1 meter wide) with images displayed on both side walls. Given this setup, I initially thought 300 DPI at full size would be necessary. Do you think 150 DPI would still provide sufficient quality at this viewing distance?

Regarding linked images in Illustrator, if they are set as links, do they remain as external references when saving as a PDF, or are they automatically embedded? When scaling down the artwork, would you generally recommend linking the images in the PDF or embedding them for better reliability?

I appreciate your advice!

#4

The PDF is a wrapper - it encompasses all the data, vector, text, raster etc. in a wrapper to present it on screen and in print etc.

The links folder is necessary if you have Links in Illustrator via the Links panel - as opening the PDF in Illustrator to make a change would require having the active link in the folder to link back to.

A PDF should embed everything - but the Illustrator portion still needs the links folder.

At 1 meter wide - then 300 would still be ‘too much’ but at the viewing distance I wouldn’t like to go below their specs.

300ppi for litho print is a nominal number bandied around which is slightly incorrect anyway.

But this I presume is digital printing and a bit more forgiving, so I’d say 200-225 minimum ppi - but if you an get 300ppi then all the better.

It’s hard to know - and your best bet is to contact them if you’re struggling to meet he 300 ppi and ask can it be as low as 150 or 200 or what the minimum number is.

It also depends on features of the image, a sharp image of a face or a building with angular sharp edges would require higher resolution - but a scene with foggy details, or swamp, or very little detail could be lower.

Line art images that are raster would benefit being 1200 ppi or higher.

But vector images will be fine regardless and are resolution independent.

@PrintDriver does a lot of large displays and probably has more insights than I do.

1 Like
#5

Thank you, it’s really helpful

#6

150ppi at actual size is considered optimal for inkjet/dyesub prints for banners and what not.
I usually tell my clients 100ppi or better if at all possible.
Anything over 200 is overkill for the machinery.
Even for line art.

For example, if the actual artwork size is 200 cm x 150 cm at 300 DPI, should the scaled-down version be 50 cm x 37.5 cm at 1200 DPI to maintain image quality? (I doubt if 1200 dpi is possible to export in illustrator

Yes this is correct, and yes you can export resolution as 1200ppi out of illustrator.
One thing to be careful of though is your Raster Effects Setting. If you are using resolution dependent filters like drop shadows, you have to change that to “1200ppi” (under Effect in the top bar menu)
You wouldn’t be working at 300ppi on the final though…

It’s weird they want an editable PDF as well as the links (we always ask for native files.)
To be safe, you might send them your .ai file with images linked as well as the PDF.

As for “no larger than 25% scale” that is also a weird one. I think they actually mean, don’t make your file smaller than quarter-scale. Some rips have issues with scaling over 400%. I could be wrong. It’s weird wording. For something as small as 80cm x 50cm, I’d highly recommend sending at 100% actual size. Scaling can introduce errors on the design side, as noted above.

#7

Why is that? Is it so you can make minor production adjustments as needed?

#8

Designers can’t possibly have all of the profiles for all of the machines/media/ink combinations available out there (especially since there are many dedicated printers out there with proprietary systems.) A lot of places that do ‘custom’ stuff or one-offs (ie not run as gang prints) have their machines dialed in to be pretty darn close to true on color (in gamut.) If you send a PDF with generic profiling, you get generic colors out the other end. Messing with PDFs to ‘match the Pantone’ or trying to color correct embedded images is considered ‘heroic’ - It takes time, with applicable charges. We’ll take PDFs but always suggest you buy a hard proof. Or love what you get.

1 Like
#9

I’m glad I asked. I’ve wondered why digital printers typically ask for the source files and offset printers rarely want anything besides a press-ready PDF. That’s good to know. Thanks.

#10

So I’ve submitted the final file, and they mentioned they will send a final print proof to me and my client for approval before proceeding with printing.

I’m working remotely and not in the same country as the printer and my clirnt, so I’m unsure how effective a proof sent digitally will be. To my knowledge, a proof is something they print out for us to review in person. Because of this, I plan to ask my client to review the print out themselves and confirm if they’re happy with everything.

What should I pay attention to in this final proof? What should I advise my client to focus on when reviewing it?

#11

Before the printer sends the proof (your side):
Double-check the file setup
Make sure the scale is correct (especially if working at 25%)
All images are linked or embedded properly
No missing fonts or substitution errors when opening the PDF

Colour mode
Everything should be CMYK
Avoid RGB or unmanaged spot colours unless explicitly required

Bleeds and safe zones
Bleeds included
No important content outside the safe/live area
Stick to the printer’s template if they provided one

When your client receives the physical proof:
Spelling and details
Triple-check all text, especially names, URLs, phone numbers and email addresses

Colour accuracy
While not 100% perfect (especially for dye sub or inkjet), check for anything wildly off
Watch out for colour casts on greyscale images

Image clarity
Get in closeare any images pixelated or soft-looking?
If it looks bad on the proof, it’ll look worse full size

Alignment and layout
Make sure logos and elements are lined up and spaced consistently
Watch for centre alignment being slightly off — easy to miss, easy to regret

Continuity across panels
For wraparounds or wall-to-wall visuals, check that the joins match
Misalignments can ruin the flow of a great design

Ask your client to view the proof both up close and from a distance both matter in an exhibition setting

Have them send you photos of the proof so you can have a quick look remotely
Don’t be afraid to request a second proof if something’s not quite right
Make sure they confirm the proof is an accurate reflection of the file you supplied

If you’re ever unsure ask. A short delay now beats a costly, high-res disaster later.

#12

Proof PDFs are for content only.
Not for color.

Hard proofs, those should be viewed at the viewing distance expected and under the same lighting (or close approximation.) Inkjet print colors shift dramatically depending on the temperature of the light hitting them. Varying light temperatures pick up the various ink droplets in different ways. I usually tell clients to take them near a daylight window (but not full sun) and you will see pretty close to what we see in a 5K light booth (which is standard for color matching.) I had a client look at a proof in my office and reject it. As we walked across the shop, past some windows, the color shift on the print was dramatic. It ended up being approved once we dialed in the approximate light source they were using on site. This is also very true if using a light box backlit image. Old box with cool florescent tubes is color corrected differently from a new light box with cool white LEDs. (we make our top line lightboxes WW/CW LEDs with a variable dimmer so that can be adjusted.

Mini prints, if not full scale sections, can be deceiving, as images ‘open out’ when enlarged. They can can shift slighty in density. Depending on ‘trade show’ or ‘museum quality’ this can matter.

The biggest issue I see on things when working in scale is gaps. An unintentional fraction of in inch gap between elements gets larger as the file is enlarged for print. Where I usually work in 1:10 scale, a 1mm gap becomes 10mm on output. That’s pretty visible. (not that anyone ever has a 1mm gap in a 1:10, but for illustration purposes, that works.) A white line is a white line even if it is 1mm at final size. Can especially suck if at eye level. :slight_smile:

#13

@smurf2 @PrintDriver Thanks so much!

They’ve sent me the PDF proof, and it looks like you’re right, @PrintDriver—it’s primarily for content review rather than color accuracy. They emphasized that it’s meant to ensure my job is set up correctly—checking for misspellings, grammatical errors, missing fonts, reflowed text, and misplaced images.

The funny thing is, when I zoom in to a comfortable reading distance, the text is pixelated and unreadable. On top of that, I noticed they incorrectly set the bleeds in a few places, lol. I’ll ask them to clarify and send a higher-resolution version.

What surprises me most, though, is the color deviation, which falls outside my expectations. Since this color will be used as a background in some of the most noticeable areas, I’m concerned about the accuracy. (it’s just that one red color btw-my artwork only used three colors aside from the logo and images: white, black, red)

I understand that CMYK works differently from RGB and that CMYK colors generally appear slightly duller. The color deviation in the proof might be their attempt to replicate the actual print result, though I’m skeptical—since, at the end of the day, it’s still a digital file and won’t perfectly match the final print.

I’m not familiar with printing practices abroad (both my client and the printer are based in the UK), but is it common to request a hard proof specifically for color accuracy?

Here in Asia, when we say “proof,” it typically refers to a physical printout, even if the material or paper isn’t final. This allows us to closely review the colors. So when they mentioned sending a proof, I (mistakenly) assumed they would send a printed version to my client.

Would appreciate any insights on this!

#14

Just to chime in on the proofing and colour accuracy side of things this is one of those tricky areas where expectations can go off the rails if you’re not clear up front.

If colour accuracy is critical (like, client-picks-up-one-thing-and-it-needs-to-match-on-site critical), then you’ve only got two reliable routes:

Provide a signed-off physical reference
Send the printer a colour sample or a previously printed item that the client has approved
They can then aim to match that within the tolerances of their setup

-or-

Ask the printer to send a hard proof
They run a proof on the exact stock with their machine and RIP setup
The client signs that off, and it becomes the reference for final production

Looking at a file on-screen or even a proof printed from their RIP can be miles off without calibration. Monitors lie. Office printers lie. Even professionally profiled monitors can’t match wide-format printers using custom inks and substrates.

Did you spec any Pantone or spot colours? If you reference a specific Pantone like “we’re aiming for 032C but this proof looks more like 486C” that gives the printer a target and some context. Even if they’re printing CMYK, it gives them a direction to tweak towards.

Even if you send the same file to the same printer on the same machine results can vary:
Time of day (literally, machines can run hotter or differently as the day goes on)
Stock batch variations
Operator adjustments (I get a lovely Tamarind sauce at the local restaurant but only if a certain chef is working that day, I actually ask them if he is working, cos the other chef on the books his Tamarind sauce is not as nice… - so operators can adjust things in the kitchen and in print)
Calibration drifting

I’ve seen prints shift slightly just between morning and afternoon runs. You can’t guarantee colour without proofing, and even then it’s an approximation but at least it’s a known one.

So if the client cares about the colour being spot on, they either:

Approve a hard proof
Or accept there may be slight variation

You don’t want them pulling faces on the exhibition floor asking why the green looks “off”.

#15

Thank you! I had no idea that calibrating color was so sensitive that even the time of day matters. It’s a basic CMYK color in my project, and I don’t use spot colors or Pantone at all. I’m going to email them and ask if a hard proof is possible. I don’t know what their prior agreement with my client was, but it won’t hurt to ask.

#16

Unless you send them a sample or they send you a sample.

What you see on your screen and what your client sees on their screen is going to be ambiguous and could be slightly different.

A colour sample has to be signed off by someone - or else it’s just going to be whatever.

#17

Got it, thanks!

#18

PDF proofs are for content, not color.
The resolution of a PDF proof can be reduced in order for it to be emailed. If you are seeing pixellation, you can ask for a high-rez proof that can be downloaded.

And the part about “they incorrectly set the bleeds in a few places”…That part is your job. You are supposed to supply a file with bleed.

I went back and read your initial post. Where this sounds like it’s possibly a prefab pop-up booth, were you supplied templates? The people that print those usually have some kind of spec, especially if they are a tradeshow supplier that prints on the frames they sell. Kinda sounds like that is what you are dealing with here. The “PDF” is actually probably a screenshot rather than an output proof, which is why it is pixellated when you zoom in. SOP for that kind of thing. Also could be why the color is off. Screenshots on different monitors with different settings can be wildly off and not even close to your file colors.

If this is the case, you aren’t going to get much traction asking them to “match the laser print.” Possibly the four most dreaded words I hear on occasion. You won’t get that if they just want PDFs, or worse, jpgs to print from. I deal with two pop-up vendors I trust and even they don’t ‘match the laser.’ They will attempt Pantones though and you pay a premium for that. Can be worth it. One of them does do hard proofs. But usually if someone is going that route, they don’t have the time or the budget to buy all the bells.

#19

Thanks. I’m not sure if it’s a prefab pop-up booth, but yes, they did provide templates that specify the size and indicate which parts need the design.

Regarding the incorrect bleed settings in a few places, that was indeed their mistake. In my submitted file, I set the bleed correctly, but when they generated the proof PDF, they messed up in some areas, causing certain parts to be missing the bleed.