How to get the best quality possible, when exporting to a raster with specified pixel size?

[Katarshis]

Hello community! Sorry for such a basic question.

I need to have a 13500 х 13500px | 300ppi jpg for Society6. My project mostly has vector graphics but there is one raster image as well. 

Based on this topic: https://community.adobe.com/t5/illustrator-discussions/unable-to-export-at-this-resolution-please-lo... I started to take ppi as a virtual multiplier.

As I understood, only size matters. So no harm to quaIlity will be done when exporting, even if 72 ppi selected.

But I can not simply make a 13500 x 13500px canvas & 'Export as'. As soon as the anti-aliasing option gets enabled, I start to get this famous error: "Unable to export at this resolution. Please lower the resolution and try again". Doesn't matter, if my artboard has size in inches (45 x 45), or pixels.

So far I've found 2 options for getting a 13500 x 13500 image with anti-aliasing enabled. Both through 'Export to screens'.

I set the artboard either to 3240 x 3240px, with resolution set to 300 dpi in JPG options. Or to 13500 x 13500px, with resolution set to 72 dpi in JPG options. I switch on anti-aliasing in 'Advanced settings for exported file types' in 'Export to screens'.

The first option gives much better result visually, bigger size too.

But maybe I am doing it all wrong...

[Jacob Bugge]

Katarshis,

It is true that the final pixel x pixel size is the same.

What happens in your comparison if you use PNG instead of JPEG, ususally recommended when based on vector artwork?

[Katarshis]

Thank you for an advice! PNG export looks sharper at the default view. But is oversharped, when zooming. Which is not necessarily a bad thing and can potentially boost printing result. But unfortunately I do not have an opportunity to check this right away. So I decided to stick with the best impression that I can get from observing an image on a monitor. I have a lot of thin lines in my design (https://foundation.app/collection/mlh), and JPG export with Baseline compression gives them a more smooth look.

[Jacob Bugge]

You are welcome, Katarshis.

I believe the JPEG compression may be described as a soothing smoothing woolliness, and the obvious goal is to make the artwork look right, whichever way leads to it.

For some (or no) reason I came to think of this other recent thread, dealing with (very) thin lines,

https://community.adobe.com/t5/illustrator-discussions/strokes-exported-from-illustrator-are-not-sho...

[Katarshis]

Amazing stock of information, thank you!

[Jacob Bugge]

You are welcome, Katarshis; and I for one hope that you will share your findings (also) concerning print.

[Ton Frederiks]

If you want 13500x13500 just export at 72 ppi.

In Photoshop or (Apple Preview) change the image size to 300 ppi without resampling.

[Katarshis]

Thank you for comment. But as as I mentioned above, if I export in 72 ppi, I get a result that is worse.

[Ton Frederiks]

Of course, more pixels will give you a better quality, but if you need 13500x13500 at 300 ppi, that's what you get.

[Katarshis]

So you are saying a 13500 x 13500 px file that was exported from 3240 x 3240 px canvas with 300 ppi export has more pixels, than 13500 x 13500 px file that was exported from 13500 x 13500 canvas with 72 ppi? That's a bit odd) Also the output file that was exported as specified in first option already has 300 ppi in specs. So not only it has better quality, it meets the requirements without farther manipulations.

[Met1]

13500 x 13500 at 300ppi v 13500 x 13500 at 72 ppi.

Do you see the difference?

[Ton Frederiks]

13500 px is what it is at whatever resolution you specify. Resolution is metadata, it does tell how many of those pixels should fit in an inch, it does not change the amount of pixels.

[Katarshis]

Thank you everybody! I was filled with the knowledge of how deep the rabbit hole is and rooted in the understanding of PPI as a metadata. For my project I decided to stick with export of 3240 x 3240 px artboard via an 'Export for screens' option, JPG 100 / Baseline (standard) compression / 300 ppi.