Confusion with bleed and scaling PDFs

[JP23]

Hello,

I was wondering if someone could help with a potentially silly (!) printing question. I have made a number of PDFs with 0.125inch bleed. As I was zooming in and out of the file to check something, I realised that the bleed area became larger and smaller (being zoomed obviously, as you would expect it to be, being part of the file). However, this then made me wonder if this means that the bleed area will be bigger/smaller depending on the size of file that is printed, even if the template was set up for 0.125 inch bleed. For some reason, I thought this meant that it would be 0.125 inch bleed, regardless of the size is it scaled to (i.e. 20:25 inch print would have 0.125 inch bleed and 8:10 inch print would equally have a 0.125 inch bleed).

Not sure if this makes sense to anyone and/or if anyone could clarify this for me?

[Hangman]

Hi @JP23 and welcome to the forums,

If you scale your file when exporting to a pdf then 'yes', your bleed will be scaled by the same percentage but if you're applying a 0.125 inch bleed to any document size whether 20" x 25" or 8" x 10" then so long as the file is exported at 100% size the bleed will remain 0.125" for both files.

[JP23]

thank you so much.

 

I didn't actually know that I could scale my file when exporting.  What I am actually doing is create a file that measures 16*20 inches with a 0.125 bleed and exporting that to PDF (without scaling up).  So if someone were to print a PDF created that way and 'scale it up' for the printing process (however they do that), would that bleed area be increased do you know?  Lets' say they use the 16*20 inch file to produce a print that measures 32*40 - would that then have a bleed of 0.125 inches would you know?  (Sorry if you've answered this already, just making sure I understand correctly)...

[Hangman]

Hi @JP23,

If they printed your file at 16" x 20" the bleed would remain at 0.125" if they printed it at 32" x 40" then the bleed would scale with the file and become 0.25".

So if they are going to print your 16" x 20" scaled up to 32" x 40" and you need to maintain a 0.125" bleed after scaling you would need to apply a 0.0625" bleed to your artwork which when scaled up will become 0.125".

[JP23]

that's exactly what I wanted to know

thank you so much for your help - very much appreciated

[Hangman]

That's absolutely no problem at all, happy to help...

[JP23]

I would help back, but I would probably need to know something first, lol

[JP23]

Sorry, there is one more thing I was wondering about and wonder if you might know the answer to this too?  I have added a 0.125 inch bleed to my PDF (which is 24*36 inches), but in the document properties, the document size is 24.86 inches by 36.86 inches.  Do you know if the measurements of the area outside of the bleed are set or if they can be adjusted?  Also, does this mean that the 'white area' outside of the bleed area is always 0.735 inches or is this affected by the size of the bleed as well?

 

Sorry for all the questions, but just posting in case you happen to know...

[Hangman]

The 24.86 inches x 36.86 inches is the size of the Media Box, i.e. the size of the file including the crop marks...

The area outside the bleed will vary depending on which printers marks are included e.g., if registration marks, colour bars and page information were included the area outside the bleed would be larger to accommodate all the additional information and subsequently the Media Box size would increase to suit.

[Oufti]

1 hour ago, JP23 said:

I have added a 0.125 inch bleed to my PDF (which is 24*36 inches), but in the document properties, the document size is 24.86 inches by 36.86 inches.  Do you know if the measurements of the area outside of the bleed are set or if they can be adjusted?

This is probably because your document includes some kind of printers marks. 

In order to print them alongside your document, the actual size of the sheet of paper used by the printer must be greater than the final document size. It is called Media box, which is larger than the Bleed box, itself larger than the actual final document size (Trim box). 

As @Hangman explained, it is like a Matryoshka doll.

Here under, trim box is in ochre, bleed box (outside the trim marks) in violet and media box (containing the printers marks) is transparent. 

[thomaso]

2 hours ago, JP23 said:

I didn't actually know that I could scale my file when exporting.

You can for various file formats but not for PDF export.

2 hours ago, JP23 said:

So if someone were to print a PDF created that way and 'scale it up' for the printing process (however they do that), would that bleed area be increased do you know? 

For printing you have a scaling option. It is common use for large prints, such as billboards, exhibition/fair walls etc. Those get designed in scale (e.g. 1:10) and then printed in scale (e.g. 1000 %). Then bleed needs to be increased, too (it wouldn't be useful otherwise). Until some years ago the PDF specification had a limit of max. 5 meters width/height per page.

[Hangman]

11 minutes ago, thomaso said:

You can for various file formats but not for PDF export.

Unless you print to PDF in which case you can…

[thomaso]

3 minutes ago, Hangman said:

Unless you print to PDF in which case you can…

... while this touches again the difference between "print" and "export". If you print to PDF you don't have PDF options, e.g. to choose a certain PDF version, a colour format or profile, font embedding or curving, or image resolution, resampling and compression values.

[JP23]

Fantastic.  Thank you all so much for your responses - all extremely helpful.

[JP23]

Would anyone know the answer to the following related query by any chance?  If I have a design which extends to the edge of a file (e.g. background contains a colour and not a white background), is there any way I can know how much 'white border' will be visible when I got to get it printed, without actually have to print it to see?

I am sure there is a technical terms for this 'white border' which is visible in a file where no bleed has been set up, but I just want to find out if there is a way of finding out how big that actual area is?

Hopefully, this makes sense..

[Hangman]

Hi @JP23,

It would possibly help if you could elaborate a little in terms of what it is you are looking to produce and how it will be printed, e.g., if you have a background containing a colour then if printing yourself, if your printer can print edge to edge then you will see no white border but if you printer doesn't print edge to edge the printer will have fixed margins, usually greater at either the leading or trailing edge of the print but you should be able to find out the printer margins for your specific printer in the manual or online.

If however, you are having something printed at a print shop then depending on what it is and the quantity it is likely the print company will print multiple instances of your artwork on a larger sheet of paper and then trim the artwork after printing.

If you can let us know what it is you are creating and want to print and how it will be printed we can hopefully provide some better and more helpful information for you.

[thomaso]

9 hours ago, JP23 said:

If I have a design which extends to the edge of a file (e.g. background contains a colour and not a white background), is there any way I can know how much 'white border' will be visible when I got to get it printed, without actually have to print it to see?

No. It does not depend on your document or your PDF export settings but on the way how it gets printed. For instance If you print on an office printer (inkjet/laser) than certain hardware has certain areas where it does not print, while there are also printers that allow to print on a sheet until its edges. For a 'professional' printer hardware like an offset print via a print service it depends how the prepress process gets defined, e.g. what paper size and what imposition setting get used.