Photoshop CC saves PNG files bigger than some PNG-specific tools

To be fair, there are a number of optimization techniques that will also work quite well in Photoshop:

http://www.smashingmagazine.com/2009/07/15/clever-png-optimization-techniques/

Btw, you do not need a plugin to convert transparency to a layer mask (the above article tells us to install a special plugin, but there is a "transparency to layer mask" option in the layer menu of Photoshop).

Having said that, CQ still does a better job. And is quicker and easier to use. And Photoshop's save for web function does not support full transparency for indexed png images - and that is the main concern here.

Well, there is plenty of good evidence and some examples in here of why Photoshop's handling and output of .PNG files is not as good as it ought to be for anyone who creating images for the web. All we can do is hit "like" at the top right of this page and hope that a page with a few likes gets noticed by the development team.

...Unless anyone here happens to know of a writer for a popular computer arts or web design publication? I imagine that the headline "How Adobe Could Make the Internet 4x Faster" would be pretty interesting reading for a lot of web designers! Not strictly true perhaps, but it piques interest and gets discussion going.

Oops, sorry Noel, I though your were responding to my post. Did you compare my versions?

Here are my versions done in Color Quantizer:

logo_no_effect.png 7254 bytes 16 colours

logo_no_effect_8.png  6490 bytes 8 colours

logo_no_effect_6.png  5,851 bytes 6 colours

logo_effect_256.png  24,974 bytes 256 colours

logo_effects_128.png 19,274 bytes 128 colours

logo_effects_64.png  14,933 bytes 64 colours

The original effects version contains 4604 unique colours. The 128 colour version looks identical, and only by zooming in dramatically can any differences be discerned. Honestly, any of these versions look visually identical to the full colour originals - I placed all of these on a white canvas, and even when zoomed in I could hardly see any difference at all.

This, my friends, conclusively demonstrates how abysmal Photoshop's PNG export really is: the version with effects is equal in size or even smaller(!) when exported from CQ than the plain version exported in Photoshop.

Photoshop's versions are a minimum four times larger in file size, and in the worst case five times larger in file size.

In CQ the user can choose to limit the range of colours from 16, 32, 64, 128, 256, 512, 1024, 2048, and up to 4096 (or anything in between, and the user can set a lower value than 16 by manually typing the number). Also, a simple quality mask brush allows you to control which areas' quality should be given preference in the reduced colour set. In addition various dithering options and "expert" settings are available to further enhance the quality and reduce the file size.

PNG export in Photoshop is in dire need of a modernization - I would argue it is unusable for current web work. 'nuff said.

Don't even bother with Photoshop and the png export for the web. What I do is save for web as a full 24 bit png with alpha, and then use Color Quantizer to properly optimize the png.

http://www.softpedia.com/get/Multimedia/Graphic/Graphic-Others/Color-quantizer.shtml

Try it, and create fully transparent png images at a much reduced bandwidth load.

For mac imagealpha is a good alternative (better than Fireworks), but it does not support colour palettes above 256 colours with full transparency, unfortunately.

"Save As" will save metadata in PNG (CS6 didn't write all the metadata it was supposed to).

SaveForWeb lets you control whether the metadata is added or not.

What are your results if you use Save for Web for the example png file?