Reminding all that PJ previews over 10k do not show in the front page when first added and will not show in the weely showcase (WS) or Hall of Fame (HOF)...
You can easily check your previews with Yanrishatum's amazing Image Specs Tool.
Note that .gif files almost always are ok but if you output .png files then .png8 is always better than .png24
If your file is big in size then its likely you are using .png24
A lot of issues arise from gamma corrections and truecolor (png24) vs. indexed color (png8) and some is explained HERE
Your pixel app already likely has options to control your file sizes but if you need an online editor that works really well then try THIS one. GifMaker.me
THIS article on optimizing gif files explains some details.
THIS article on general page weights has some useful info too.
THIS article in on compression and also has some relevant info.
These links have been added to the links section for future use.
Thanks 8 Bit Dreams
My preview is ~10K, is there a way to know if it's considered less than 10k or not, if it's still in public queue? Maybe some indicator at the site with warning?
It's a fairly dumb restriction and regardless of intentions pixel art has changed. No need to punish people who don't adhere to the restrictions people had to deal with 20 years ago. Especially since most of the time the difference between showing up or not on the front page is whether you remember to index your png. If you have to write a news post reminding people how to actually show up on the front page then I think things need to be reconsidered.
Want to keep the spirit alive? That's what the weekly challenges are for!
Pixelart roots are about restrictions and limitations.
The 10k preview thing is just a way to keep the spirit alive.
So what WAS changed in the v3 update, as it seems none of the usability issues were addressed. 10k in this day and age is extremely limiting for little gain... why wasn't this and other issues fixed up? Pixel joint, from a user point of view, seems no different than it was 5 years ago.
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Also when I do a 100x100 preview it's always 10K - 10,5K. Thanks for mentioning pngcrush though, it saves a little