Need a basic reminder of how to scale images for export to different size files

[tdcarp]

I don't use AI all the time, but thought I understood the best way to scale an AI image for export.  But, following the technique, I'm getting some terrible quality export files.  If someone sees something I'm missing....

I started with a 640x640 pixel artboard.  No particular reason for the size choice.

The artboard contains 3 text entries, and an 8-point compass rose.  The rose was built using the star tool, and some triangles.  It ends up including 2 4-point stars, and 8 triangles used just for coloring.

The text entries are simple 2-3 word phrases.

After building the graphics and text, I selected all objects, and scaled them to 20%.  Created a new artboard, and collapsed it around the graphics (Object>Artboards).

I then export to PNG using the artboards.  With one named "100pct" and the other "20pct", the result of the export is the two files.

Given all the scaling appears to be vector objects, my expectation is the graphics in both files would be high quality.

But, when I place or insert the 20pct PNG image, it's quite grainy.

I actually get acceptable results by inserting the 100pct PNG image and then scaling it to 20%.  But there, I'm changing bit images, so the tolerance won't be much.

What am I doing wrong using the approach of scaling vector images into their own artboards.  Shouldn't I get equally good quality in each of the PNG files?

[tdcarp]

Jacob, I don't understand why my replies send when I enter a carrage return. I wanted to make a final post summarizing what I learned here as an aid to any that might get benefit from the thread. It may be that someone has set the thread to "solved". I have a document that summarizes the guidance you gave and how it applies (or not) to my graphics. I'll transcribe it in another reply. One key thing is the use of Placing the icon on the text artboard. In my case, the icon is all vector, so it's easier to use Place than to resize the original artwork. I can see the idea of keeping inserted artwork at the size needed when inserted in another artboard if the grapics include raster. Regardless, this has been a very useful thread and it solved my issue when posting originally. Thank you very much. I'm rarely disappointed when coming to the Adobe Support Community. Tom

[tdcarp]

This is the copy of the notes I kept. They weren't complete, but captured much of what was posted. Scenario: Two separate AI files: one contains an icon, and the other contains some text on an artboard with an area to include the icon (i.e. the icon is to somehow be included on the text artboard). --Environmental settings-- Guidance - Ruler Units: Set the ruler units appropriate for print-destined output (e.g. in, cm, mm), or for display-destined output (e.g. px). Scenario: The destination is print. Scenario: The icon artboard is 8.33”x8.33”, and the graphics are 5.56”x5.56”; the text artboard is 2”x1/2”. [The icon artboard and graphics dimensions are remnants of past use where the graphics were destined for display. The original icon artboard was 600x600px, and the graphics we’re 400x400px] Guidance - Ruler Ratio: AI uses points for its ruler ratio (i.e. 72 points/inch). Changes in ruler unit settings follow this ratio. [This ratio is not adjustable] Note: A good, easy-to-understand, discussion of density settings, using the scenario of “changing the PPI setting in an existing AI document”. https://design.tutsplus.com/articles/adobe-illustrator-how-to-change-ppi-in-an-existing-document--cm... --Color— Guidance – Color Scheme: Set color scheme based on output destination (i.e. CYMK for print; RGB for display). --Raster— Note: Although AI is primarily vector graphics, it does have the capabilities to hold raster. Guidance: Set to 300 PPI only if raster graphics are included, or if the graphics will be converted to raster when exported. Export to web ---- and then only if the output destination is print, or to provide some zoom capabilities when displayed. Workflow: Two approaches to getting the icon onto the text artboard: 1) copy/paste, and 2) place. Guidance: Keep the icon the same size as it’s intended size on the text artboard (i.e. no scaling). [This applies well to projects where both AI files are being created concurrently, or the text artboard already exists, and the icon is being created. If both the icon and the text artboard already exist, and the icon is not the same size as it’s intended size on the text artboard, it can be scaled, assuming it is only vector graphics, or, for raster, the PPI setting allows for some scaling.] Guidance: Base color scheme on output destination (e.g. CYMK for print, RGB for display). Place: Requires the icon be stored with PDF capabilities (i.e. not native AI). The Place still works with an icon file stored in native AI format, but the display in the Place window on the text artboard will not display an image of the icon. Instead the area will contain text indicating the icon file was not stored with PDF capability. Guidance: If there is an important difference in file sizes for native AI vs. AI with PDF capabilities, use native AI. To visualize the icon in the context of the text artboard, a temporary test file with PDF capabilities can be used. Scenario: Neither the icon or the text artboard files contain raster graphics. Guidance: If scaling is needed for the icon to fit the text artboard, assure the option to Scale Stokes and Effects in the Transform>Scale window is appropriately set.

[Danny Whitehead.]

tdcarp  wrote

The output for the test graphics is print

Apologies I've missed something amongst all this, but if your artwork is for print, why are you rasterising to PNG anyway?

[tdcarp]

Thanks for weighing in.

It's just testing.  The actual AI file is CYMK, and the final output is inserted in files like Word (or in my case, GIS maps).  Exporting to PNG is just an easy way to see the results of the test.

Tom

[tdcarp]

For some reason, my replies are getting sent before I'm finished

[Monika Gause]

Don't use returns in this comment box. Maybe it would be better to create a new thread for your issue. This one will be a pain to read.

[Jacob Bugge]

Tom,

With the new forums, all answers to anything but the OP (original post) are more difficult to make, Enter triggering its being sent, and they be threaded in the thread as you have already seen.

The safe way is to only use the blue Reply button at the top of the thread and then address the post so everyone can see whom it is for.

Since this thread has been threaded owing to its being transferred, I agree with Monika that a new thread would be a better way to continue.