Solid transparency Tileset problem

hello! I recently finished this tileset. I placed around, making some random screens when I realized that every thing in the tileset was solid. The transparency was fine but if for example I had a brick that only took up half of 24x24 the entire block 24x24 would be solid. help me please, I've worked so hard on this tileset and I don't want It to be ruined by this problem! 

The entire tileset is covered with a very-near-transparent black (clearly visible in the screenshot forming boxes around everything). It must be removed for the problem to be solved. Unfortunately, it must be removed by hand, since using like a color-select tool selects everything black rather than just the intended transparent portions (unless it's possible to set such a tool to select only areas of an identical transparency? I don't know of any way to do so), and deleting all the black from the tileset is obviously a bad thing.

You could invert the color  then get rid of the black?

Then invert back.

Inverting the color would also invert the rest of the image, making it pointless.

Wasn't actually too hard, when you put a colour that's nowhere else used in the tileset (like magenta) on a layer below, use colour-select with zero tolerance on the "empty" places with [include all layers] option enabled (or whatever it may be called for other programs) and then remove the selected parts. And then use that one-colour-layer as a mask to remove the excess black from the tileset layer. wooooo.
I hope this now turned out right. Neat tileset btw.

Don't know what program you use for tileset making, but if you use an eraser tool to remove unnecessary background, make sure to have it erase 100%, or some setting alike. Or colour everything you want to have transparent later on in an unused colour like magenta, so that you can use the magic wand and remove stuff that way.

thanks so much Paula!  

the first tileset I made I decided to do the transparency by hand with the eraser but It took a while. It came out fine though! here it is.
anyone can use them as much as you want as long as you mention me in the credits or something.

the first tileset I made I decided to do the transparency by hand with the eraser but It took a while. It came out fine though! here it is.
anyone can use them as much as you want as long as you mention me in the credits or something.

Spoiler: the green machine (click to show/hide)

exactly the tileset i was needing for my level! thanks, bunnrey!
p.s. is it okay if i change the colors a bit (green to blue and red)?

It's fine!
I glad you like them.