Reducing filesize

[mochi]

Some chapters take an awful lot to load, because each page is an enormous png file, so the entire chapter easily reaches 70~100 mb.

If you use imagemagick from any shell, you can launch this command to drastically reduce filesize without any perceptible quality loss:

for i in *png; do convert $i ${i%.*}.jpg && rm $i; done

(note that `&& rm $i` deletes the original file)

 

[ixlone]

Eww .jpgs~

I recommend PNGout!

 

[m3ch_mania]

Attn Scanlators: If your black & white PNG image exports from Photoshop are greater than 5 MB in size, consider reducing your color palette when exporting to PNG.

Black and white images typically do not need 256 separate colors. Trim it down. You might be surprised at the space you'll save.

Spoiler

 

[Kisato]

Adding to what @m3ch_mania said, you’ll notice that he’s using “Save for Web” the default shortcut for this is

ctrl + alt + shift + s

 

[Rugid]

Big png files happen because people don't change mode in Photoshop from RGB to grayscale in the first place, and to add insult to injury, they save png using "save as" and choose "compression - none". The other popular mistake is to save scans in png-24 with transparency.

Just change mode from RGB to grayscale when opening b/w scans first, and when everything is done, use save for web in Photoshop/Gimp, choose png-8, and usually 32-64 colors or even less is more than enough for average manga scan.
Also, uncheck "convert to "sRGB" (and can also set "metadata" to "none" while at it).

For those, to whom all of this is too hard to understand and too lazy to search for tutorials, use this program: http://www.mediafire.com/file/hlr1xszqildnyqn/png_for_dummies.zip/file