PNG-8 or PNG-24 on photoshop

appybank

Guys I am trying to think about image size and total size of my app. I am doing all my graphics on photoshop and saving them for web. I was saving everything as png-24 but realised file size went down dramatically when i changed to png-8. Has anyone notice any difference with png-8?

Plus the people who save as png-8, do you still optimise afterwards?

png-24 was 500k
png-8 was 230k - a huge difference

mangaroo

if you need transparency stick with png 24 otherwise 8 will be fine.

Also i optimise all the files using [cant quite find it atm, on my pc]

Eastbound

mangaroo said:
if you need transparency stick with png 24 otherwise 8 will be fine.

Also i optimise all the files using [cant quite find it atm, on my pc]

I'd like to hear which program it is!

appybank

But someone sad that gamesalad converts png8 back to png24 when you upload images to game salad. Any truth in this?

so you even optimise png8 files mangaroo?

EatingMyHat

appybank said:
But someone sad that gamesalad converts png8 back to png24 when you upload images to game salad. Any truth in this?

Why should people be sad about things like that?

firemaplegames

@eastbound: the app is called ImageOptim. It's free and will get the files down as small as possible.

Exporting your images as PNG-8 will make the file sizes smaller. Which is important if you are trying to stay under the 20MB AT&T 3G limit. Smaller file size is also important for testing, uploading, etc. Needlessly large files slow everything down. Also if you ever want to export your app to other devices like Android when it becomes available, smaller file sizes are important because of size limits and performance concerns.

However, if you use Resolution Independence, regardless if you use PNG-8 or PNG-24, when GameSalad creates the .png files for the older devices, they will all be PNG-24.

perfectanswer

png-8 has only a max of 256 colors with transparancy. Looks in many cases ok if you don't use transparancy. Transparancy looks in most cases ugly, or like cut out by one eye jack.

png-24 is full color with alpha channel. Looks best, great transparancy, but big files and huge ram ussage.

if you don't need alpha channels in some of your pictures, than use .jpg. Small filesize and looks close to .png. Advantage is the small file size. After importing .jpg's in GS, GS convert the jpg to a png, but the filesize is still small.