2011-05-17

Question about PDF purchases

 I have a question about PDF purchases, for people who like to buy things that way.  The images in my PDF are embedded as PNG's, and they bloat the PDF out to 55mb.

Is that normal for people who download these?  I could go and reduce the resolution on the images if that download size is considered ridiculously huge - but I really have no idea what the standard is.  I'd appreciate any input on this.

Thanks in advance!

11 comments:

  1. I'd say it depends (of course.) I probably wouldn't notice or think about a 55 meg pdf these days, what with the cheapness of storage. But if you want to do comparisons, you should probably look at size divided by length in pages. Looking at the latest printing of Swords and Wizardry from Finch, it's 146 pages long and 20,391 KB, so what - 140 KB per page? So if your pdf is 393 pages long, it be comparable. Of course, S&W is mostly black and white images. If you are going all glossy full color prettified pics, then I'd expect a higher size count. So - it depends. But 55mb? I still wouldn't bat an eye at that size. 200mb? Well, I might start to wonder if a pdf that size was worth the space.

    - Ark

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  2. The giga-sized cover is for printing I guess. Maybe you can try to duplicate your pdf removing the cover.

    BTW, Arkhein is totally right.

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  3. It seems to me that png scales down very well without losing resolution. It's usually compressing (or exporting to) a pdf format that leads to pixelated junk. Can you compress the pngs and resize them up to fit your document and see what that does to the overall file size?

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  4. That's the size w/o the cover. All I did was change the art from JPEG's to PNG's and embed them - the images are still largeish (> 300 dpi). I can shrink them to 300 dpi, or 150 dpi, to get the file smaller - is either a standard for PDF sales?

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  5. As a 'consumer' of pdfs I will just echo what Ark said - it depends. If the content is cool it's no big deal to me for a 55mb download. If half that size is just badly formatted art I might not keep it around (or download it if warned beforehand) unless the text really kicks ass though.

    300 plus dpi puts it in the realm of 'for print' resolution. If you want it to be more download friendly you might think about changing the art to 'screen resolution', which can be from 72 to 96 dpi (or offering both print and DL friendly version and let the downloader decide).

    Another area to take note of is the different 'modes' you can get with png format. For back and white illustrations at the very least set png to grayscale instead of RGB 'truecolor' before you save. For hard edge line work type illustrations you might even be able to convert to png 8 bit indexed (like the gif format)for some savings over gray with very little image degredation.

    For color definitely make sure you save pngs as 8 bit per channel instead of the 16 bit option that's also available. also make sure there is no alpha transparency that is unneeded.

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  6. Some PDF's I have are rather large. Not an issue, from my pov. I would keep things at Print Resolution, because some of us do print out the bloody things. And don't toss the cover, for the same reason.

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  7. The 300 ppi thing is tied to press quality and 99% of end users really don't need anything more than half that. Most folks will be printing on an ink jet of some sort and due to creep, anything over 150 ppi would be very difficult if not impossible for the end user to discern.

    Having said that, I don't really pay any attention at all to the size of PDFs that I purchase. Storage is chepa enough these days that it really shouldn't be a concern.

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  8. I would rather have a higher resolution file - that way I have the choice to print out the covers on the color laser printer and then the book contents on the b&w laser printer and get solid quality.

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  9. I know I'm late to this thread, but you might want to check the color depth of the images.

    If it's pure line-art with no gray, making it 1-bit dramatically shrinks the file (and if carefully converted, the images print better too). Depending on the image, there may be little or no loss of quality converting grayscale images to index color with 128 or as few as 8 colors.

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  10. I got it down to 6mb which I think is a reasonable size, so no worries there

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