I would appriciate if someone explained me what I'm doing wrong.
I have a png image, of 256x128 size. It has 8bits per pixel for color. Now this image's size is 97kB. I open it in photoshop, I save it as different png file, and then... this image is 7kB of size.
Can someone tell me what's wrong, or what I'm doing wrong?
"Viewing in a hex editor, that first file has a bunch of empty data. You don't seem to be losing anything by saving to 7kb from Photoshop."
I see... So it's just a bad saving on the first case. That makes sense, definetly. I noticed something else as well, but don't have time now to explain, so I will do it in the evening. Thanks a lot for checking it again!
"Aren't you confusing the opened size with the saved size?"
No. By file size, I mean size showed by windows explorer.
Ok guys, thanks a lot for patience. Below is the main cause why I started this topic, but I still can't figure it out. I thought the loss of size is the cause, but you say it's not :/
I'm not that skilled as you guys, so that's the primary reason why I'm here. I will be really gratefull if someone could give me a hint here, or some small help.
To cut to the chase, I'm trying to use a program that creates graphics for older games. This program edits particular files, that have different resolutions and different number of bits per pixel. The problem I have however is the transparency and color palette, as I never had dealings with that. The problem is, that someone created before a pictures that are very smooth, and this seems to be the cause of very smart using of transparency levels, for different colors in the palete. However, I have no idea how to achieve the same effect, I tried many things, but still can't figure this out. I will try to ilustrate the problem below.
Below is a screenshot from this application
On the right is the picture that is the root of my question here. It has to be in the format with palette of collors in amount of 16, although I have no idea where it stores the alpha channel information, as there are 4 bits for color per pixel. Well anyways, you can see on the right top corner the palette. It basicaly has only the shades of gray in this case. I can switch now to the alpha channel mask, and this is what I get:
You can see that each of the colors in the palette has different alpha values. Now what I tried is, I exported the image, I opened it with photoshop, saved it, imported it in the program, and guess what I found in the alpha channel mask:
All the information of the alpha channel for each color is gone!
Here are the examples with more colors(256):
The alpha channel mask
And now, I do the same as before, export it, save it in photoshop, and guess what, all the info is gone again:
Now loosing this information is not a problem, as I will be inputting different pictures, but my question is, how I can achieve the same effect in photoshop for my images that I will try to import. I would love to have as smooth edges as they are seen on those examples above.
I'm unable to follow the illustrations but the mention of alpha masks suggests you also look at Fireworks (free 30-day trial) and GIMP (free forever). Different programs handle PNG differently. Photoshop is actually pretty lousy for PNG, especially if you are dealing with PNG8 with alpha transparency. That type of PNG is best handled by Fireworks.
If you want to stick with Photoshop, experiment with saving from "File->Save As" and also "File->Save for Web". You get slightly different results.
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