Scanning line art

[Tony Irwin]

This relates to this thread: http://www.indie-rpgs.com/forum/index.php?topic=15427.0 Thanks to everyone who replied to that one.

I have nearly 100 images for Shoujo Story, all black and white line art. I had initially scanned everything in at 300dpi but in the book I got back from Lulu the pictures looked pretty grainy. I've started rescanning it all in again at 1200 dpi. Its a painfully slow process, I'm not even a third of the way through it. Already my Shoujo Story document is 176 meg and now won't save properly. I'm using Microsoft Publisher for layout.

Hopefully I don't even need to ask a question in this post. You're already snorting the coffee out your nose as you laugh my witless attempts to publish my game. Perhaps now your tears of laughter begin to blend with more piteous waters as you think "Poor bewildered sap, someone should put him down or help him out". And so now you crack your knuckles and start typing out something that will make sense of it all for me...

Thank you so very much,

Tony

[timfire]

After you scan the image, what you want to do is convert it to a bitmap. This will make the image purely b+W, no greys. Then, you save it as a TIFF with LZW compression. This will shrink the image to 5-10% of the uncompressed TIFF size.

If the files still aren't small enough, you can downgrade the image to 600 dpi. This, of course, will shrink the image to 25% of the 1200 dpi size.

You still want scan the images at 1200 dpi TIFF, uncompressed. You want to keep a backup of the highest quality possible. As they always say, you can always downgrade, but you can never upgrade quality.

[Luke]

Tim is absolutely correct in his description of the process.

-L

[Eero Tuovinen]

Note: I've not used Microsoft Publisher, ever. I've done lots with other layout programs, though.

First, slowness of scanning: yeah, it's slow. Can't be helped. 1200dpi, however, is definitely what you need for line art. Make sure your scanner is scanning a bw 2-color image, not grayscale or CMYK. Not only are most scanners unable to do the latter genuinely, they will also cause magnitudes larger image files. (I don't know the details of the project, but in some cases you can also use vector graphics instead of bitmaps, which are vastly more efficient with simple line art. That process starts with the artist, though, so you won't be benefiting from it in this project.) Also: do what Tim said.

Second, managing images: the proper method for laying out a large, illustrated document has you linking the images externally, to reduce the layout file size and free processing power. Most likely Microsoft Publisher allows for this, too. Look in the manual for the option of not including the image in the layout file, but instead just referring to it from somewhere outside. If these linkages are done correctly, the size of the layout file is not affected by the size or number of the images included, because the file only refers to the images instead of adding them into the layout file. However: the drawback of external linking is that if you move the image files or the layout file, the layout file loses track of where it should look for the images. The layout program probably allows you to point it to the right place in this circumstance.

Judging by the current size of the layout file, you probably have some image data in there. So try to find the option I outlined above, and see how that affects file size. Also check if the file saves properly after that. Meanwhile, we'll see if there's anybody who's worked with Microsoft Publisher around.

[Rossum]

Also, depending on your scanning software and your relative degree of Photoshop Fu, you may be able to batch adjust all of your images. So you scan everything in first with good settings, then batch convert all the images at once. I know it's possible, but unfortunately I don't know the specifics. A search on 'photoshop batch' gave some promising results.

Good luck!

MDK

[talysman]

After you scan the image, what you want to do is convert it to a bitmap. This will make the image purely b+W, no greys. Then, you save it as a TIFF with LZW compression. This will shrink the image to 5-10% of the uncompressed TIFF size.

If the files still aren't small enough, you can downgrade the image to 600 dpi. This, of course, will shrink the image to 25% of the 1200 dpi size.

You still want scan the images at 1200 dpi TIFF, uncompressed. You want to keep a backup of the highest quality possible. As they always say, you can always downgrade, but you can never upgrade quality.

an interjection: before converting to bitmap, use threshold. after the bitmap conversion, you can go through and erase stray pixels. I have done this before with good effect, although I was hazy on the details, so I checked with someone who scans line art frequently, and he confirmed: threshold, then bitmap.

[Joshua A.C. Newman]

If you're using, Photoshop, it'll ask you for the threshold when you convert to a BMP.

[talysman]

If you're using, Photoshop, it'll ask you for the threshold when you convert to a BMP.

unless I'm missing it, it doesn't ask in The Gimp, so you have to manually apply Threshold, then Image > Mode > Indexed and use a 1-bit b&w palette. the rule for other image editors, then, is to see if it asks for a threshold; if not, abort and apply Threshold manually.

[timfire]

One other quick thing---when you look at a bitmap onscreen, it'll look not-so good, kinda jagged. But when you print it, it'll look incredibly clean.

[Joshua A.C. Newman]

Oh, and yeah, 600 dpi should be fine unless you've got really fine details, like tiny text or something.

[madelf]

Here's a different approach for you.
Take the 300dpi line art scans you already have and convert them to grayscale mode (or alternately rescan them as grayscale at 300dpi). Then save them as TIFFs. They'll print fine.

What this does is take away the jagginess and graininess that you'll get using lineart settings, but the images will still remain very sharp and black. I've had images I've done this way printed through lulu.com for my playtest book, and by multiple publishers through various POD and traditional printers. They've always looked great. There is no reason you need 1200dpi image files to print a good quality book.

[Joshua A.C. Newman]

For what it's worth, I disagree with madelf. You don't need 1200 dpi, but the blown up, half-scale TIFF images will have chunky edges even at 600 dpi.

By the way, BMP and "bitmap" are different things. A bitmap TIFF is probably what you want. I may have misled you earlier about that.

[madelf]

For what it's worth, I disagree with madelf. You don't need 1200 dpi, but the blown up, half-scale TIFF images will have chunky edges even at 600 dpi.

Blown up, half scale? Where are you getting that from?
If the final image is made larger than the original, then it's going to look crappy, of course. But I don't think anyone was talking about doing that.

[Tony Irwin]

Fantastic, thanks everyone.

Tony

[Jake Richmond]

Hi Tony.

600 dpi greyscale images always work fine for me.