adding form fields dramatically increases file size
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I have a Word doc that needs to be form fillable PDF.
Word doc = 24k
Converted to PDF using Acrobat DC = 44k
Added 5 text form fields = 1.2MB!!
That's a dramatic jump in file size from the original, unedited PDF. Is there something that can be done about that?
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Start again, this time use the font from the top of the list, Helvetica.
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OK, I can do that but... what if I need the font to match what the rest of the document is (and it's not Helvetica)? Since the rest of the text on the converted doc is all the same font as the form field textbox I was adding, I'm not sure I follow why that would cause such a dramatic change in file size.
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Every font, except the few at the start of the list, has to embed the entire font file. Font files are often over a megabyte, so this is just what happens. You can decide is a tradeoff of font accuracy is the answer, or look for a font with a smaller font file (hard).
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The explanation as to why this is happening is that when you use a font you can embed it fully or partially ("subset embedded"). When the font is only used for static text the latter is enough, as only the definitions of the characters that are actually used need to be included in the PDF (so they can be scaled up or down, printed correctly, etc.). However, when you select the font to be the one used in a text field you can't control what characters the user will enter (well, you can, but let's ignore that for the purposes of this explanation), so the entire font, the full set of characters it supports, has to be embedded in the file, and that can be quite a lot of information, hence the bigger file-size.
Adobe has decided very early on to mitigate this issue by including a small set of fonts as "built-in" to the application, so they don't have to be embedded in each file. Those are the fonts that appear above the line when you open the fonts drop-down. If you use one of those fonts, your file can remain small as it relies on the application to contain the necessary data to display them.
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Thank you for you replies. I've been doing some more trial and error experimenting. I realized I was setting a "Default Value" in the Options tab for my form field so that I could line it up with other text on the page. I suspected that was an issue with increasing what Acrobat that it had to embed. So I started over and didn't set any Default Values. Starting with 25k PDF file (no form fields yet), I was able to lay on my form fields (a bit more than a dozen) and keep it under 40k.
But I will tell you it seems "sketchy." I started another one (I have many documents that need to be turned into form fillable PDFs, so I'm looking for a repeatable process here!). I started with a 124k PDF (a one pager, but more text than my first one, so maybe that jives). I added one form field, but before I saved it, I set the Font to Helvetica as suggested, then saved. The file size jumped to over 850k!
I'm really struggling to figure out a process here and keep these file sizes small, especially since all my source Word docs are less than 30k. Jumping up to a 1mb or more seems crazy.
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Be sure to AT NO TIME have other fonts in form fields. Not even if you don't save it with those fonts. There seems to be an Acrobat bug which means it can't properly unembed fonts, and worse it sometimes embeds a pile of fonts you never even used. 1MB is not the least bit crazy, because many fonts are larger than that just by themselves. Arial is a particularly bad choice, and the common Windows fonts. Microsoft have added support for more and more languages to them, and the whole font must be embedded for form fields.
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Make sure to use Save As and give the file a new name. That will force an optimization of it and can reduce the file-size dramatically.
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Again thank you both for the quick replies! I've tried SaveAs, just doesn't work. I think there must be something to the notion that there's a serious bug in Acrobat DC that can't handle un-embedding fonts (that, by the way, you aren't even using).
I discovered I had to create a new / blank PDF, add a form field to it and set it's properties to generic stuff (like Helvetica) and then right-click that, choose Use Current Properties as New Defaults. Then, when starting from my fresh, somewhat smaller PDF but as small as I can get it when converting from Word..., then, add a new formfield (with the freshly minted defaults), then do my SaveAs. And... while it adds some to the file size... not "as bad" as before. I started w/ a 21k Word doc, converted to a 113kb PDF; added form fields and ended up at 134k.
So touchy and not very reliable...
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I'm wondering if anyone has experience with another software tool to create/edit PDFs besides Acrobat DC? Any better results with managing the unembedding of fonts at any point during the edit lifecycle?
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Take a empty PDF document with one page and add the pages of your form. Remove the empty page and save the file.
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- Always make sure you always end the form with Save As, not just Save.
- This behavior is not "unreliable", on the contrary, it is perfectly predictable.
You should read this article about the "14 Standart PDF fonts": https://www.abracadabrapdf.net/ressources-et-tutos/js-et-formulaires-ressources/les-14-polices-stand...
Googol translate is your friend.
Acrobate du PDF, InDesigner et Photoshopographe
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FWIW, I ALWAYS do Save As... every time. I have scores of v2, v3, v4... files in my work folder until I'm done and can delete all the intermediate versions!
I think Acrobat has some issues w/ it, I may call that unreliable or buggy or touchy...
I have a Word doc, convert it to PDF. First time in Acrobat, I do Save As Other, Optimized. And I unembed any fonts there. That always brings the file size back down. Yet when I open that file up in Reader, go to Document Properties, Fonts... it always shows some leftover font (for example, Ariel), that never even showed up in the Unembed dialog as a choice when optimizing. In my Word doc, I have no headers or footers. I have done a Select All and set a specific font. So where is Acrobat picking that up. But that initial optimized version, even so, is ususally pretty small, let's say under 50k, even less if it's a simple one page doc.
Now let's say I make the cardinal sin of adding a form field and changing the Font to one of the non standard ones. Save As. There's the hit. We're at 1mb file size. Oh that's right, it's dealing with that font thing. Change the font on that form field back to Helvetica. Go to Save As/Optimized and go to the Font page, there's nothing there to unembed. I do the save anyway and of course it doesn't change the file size. It's still huge. Now I have to start completely over, from scratch. If I had already done a bunch of edits and adding a bunch of form fields, all that work is gone because I have to start over. (Or go back to one of my intermediate versions and pick up where I left off... because that's how I've learned to roll in Acrobat!)
I understand if I choose some custom font, it wants to embed it and that will cause the file size to go up. But managing those fonts, that process, is the issue. If I choose to not use the font, I should be able to unembed it. That option is lost. So yeah, I think it's unreliable. That's my .02.

