Honor scale on PDF import

[Dahzee]

I don't know if this is the correct forum for this, so apologies in advance and also if it has been discussed already.

I tried to open a PDF (in Acrobat Reader) of some artwork yesterday and even though the measurements were correct, when I actually opened the PDF in CorelDraw, Affinity Designer and Autocad it was much smaller than it measured in Adobe Reader.

I knew there was something strange going on as I already had wet proofs of the job and it measured correctly.

I was cutting these proofs out on a CAD table, so I contacted the Printer and asked them to open the PDF in Illustrator I had been sent to check if the size was correct.

The reply was on opening the PDF a message box opened with the following:

"A scaled artwork will be shown after importing as it is created on a large-sized canvas.
To view the artwork in original dimensions, choose Preferences> General> Honor scale on import

Do you want to enable this preference now?"

It turns out that the PDF is scaled to 1/10th of its original size and this is deliberate by Adobe.

Now, this is fine if you are using an Adobe product but if you aren't you have no idea the artwork has been scaled.

I don't know all the ins and outs of PDF's but I thought they were now an ISO standard and the specification was agreed by an independent group.

So if Adobe are scaling the PDF to suit the limitations in their own products it is going outside of the specification and without anything in the PDF saying it has been scaled there are going to be a lot of people caught out by this.

Has this happened to anyone else?

 

[abc]

How big was the original PDF? The PDF specification has a size limit of 200 x 200 inches, but there is a technique called 'user units' or page scaling to make the document larger.
What application generated the original PDF?

 

[Dov Isaacs]

The scaling capability is actually part of the ISO PDF specification and was envisioned for use when creating content that was destined for humongous rendering (such as a large billboard) that goes beyond normal PDF dimensions. Use of a scaling factor is absolutely not “out of spec” in any way.

As @abc queried, it would be helpful to know what application actually generated the PDF file. Furthermore, it would be helpful if you posted an example.

- Dov

 

[Dahzee]

Thanks for the replies,

@Dov, I got my "is it" the wrong way round and it came out as "it is", apologies.

As I mentioned I don't know the specification very well :-(

I have attached the PDF and it is only a 3 page with a sheet size of almost B2.

Don't take any notice of the lo-res 4 colour image as I presume this is another issue, thankfully nothing to do with me.

I am only guessing here, but I suspect the artwork has been set up by somebody who isn't fully versed in creating artwork for print.

My role in this saga is I am a freelance packaging designer, commissioned by the printer only to cut the proofs out.
I didn't generate the original cutter guide and I have no knowledge of (or access to) whoever created the artwork.

 

[abc]

Yep, you have a Page Scaling factor of 10 in this PDF, that's where the issue comes from.

 

[Ferran]

Checking the PDFs with a preflight tool could help to detect this.
I have used the profile “Sheetfed offset (CMYK) GWG 2015” and an error for the Scaling factor is reported.

 

[Dahzee]

Thanks for the replies and how I might discover this situation in future.

Judging by the cost of preflight software I can't see myself buying it just to find this out on the odd PDF that has been scaled.

It is a shame that the file when saved doesn't have a suffix or prefix indicating that it has been scaled so any user will be aware of this.

It would probably be more economical if I subscribed to Illustrator so I get the warning unless anybody has a better idea?

Thanks again for taking the time to look at this and offering up your assistance.

 

[TJPrinter]

It would probably be more economical if I subscribed to Illustrator so I get the warning unless anybody has a better idea?

How about Adobe Acrobat Pro? Preflight is built into it.

 

[abc]

I think the takeaway for you here is that that Page Scaling flag is probably applied by the originating design application when you exported the PDF. I think Adobe Illustrator does that by default? (I stand to be corrected).
The approach would be to design within the 200x200 inch limit, and then tell the Print Service provider that the file needs to be scaled up x% during production.
A lot of printed material like billboards are produced like this, the file is produced to a reduced size and enlarged later.
That might be a solution for you.

 

[Joe]

I am only guessing here, but I suspect the artwork has been set up by somebody who isn't fully versed in creating artwork for print.

Actually if this is this something that needs to be output larger than 200 x 200 inches then the person that created this file is the one that is fully versed in creating artwork for print.

 

[Dahzee]

@Joe, the file is only 700mm x 500mm, I wouldn't be surprised that the front, back & cutter guide were all produced originally on one large artboard and then saved into a 3 page PDF, so Illustrator probably thought it was still one big file, I'm just guessing as I don't use Illustrator.
It is just unfortunate that there are only facilities within high value specialised software that picks this scaling up.
The galling thing in all this is that people are creating cutter guides in Illustrator as PDF's which most of the time don't work and as they are PDF's as we all know this is supposed to be a final format and not one that is intended to be opened up and altered. It is a shame designers in the UK aren't aware of how to create cutter guides separately from artwork and supply the diemaker with a file in the correct format that they can work with (Americans have DDES, we have CF2, most designers have never heard of these formats as they are only created by Packaging CAD software). I'm amazed these formats aren't included in Illustrator, Indesign and Coreldraw as they are open formats. Many a time I have had diemakers complain that they have had to try and pull the cutter guide out of the artwork, or all the lines are a single colour and not even dashed lines to help tell whether the line is cut, crease or perforation.
Sorry rant over

 

[Dario]

Sorry rant over

I feel you - I have the same problems