discharging fabric

I've been doing a little playing with discharging fabric, which is just a fancy way of saying I threw some of my fabric into bleach water. I would love to try to dye fabrics someday, but for now, this is a good experiment to tide me over. It's pretty fun.

After discharging on the left, originals on the right

From what I've found, the best candidates are high quality fabric. The cheap stuff seems to just get ruined. I chose some fabric that I had scraps of that the color was a bit challenging to work with. A trip through the bleach water yielded good results. At least on these.

left-discharged, right-original

This yellow/gold piece was something that I found in a scrap bin at a quilt shop I visited. It was one of those deals where you fit all the scraps you can in a bag and you pay a flat fee. It has a weird brown thing going on, but I thought I might be able to use it for something. I like it a lot better after a bleach bath. The rest of the piece will be in my next batch.

This one I just bleached the whole piece. It only softened the pink parts. The red is pretty much the same.

Some fabrics I tried came out unchanged.

One last thing I learned...don't leave it in for too long. I threw in a small piece, got distracted, went back to my fabric the next day. No color left whatsoever. Oops.

Have you ever tried discharging fabric?

edited to add: There has been some great discussion on this in the comments. Linda brought up a good point about the bleaching process needing to be stopped. Needled Mom helped me out by telling me that she soaks the bleached fabrics in a mixture of vinegar and water to stop the bleaching process. (I'm using a mix of half water & half vinegar.) As far as how much bleach to water ratio, I would guess that i used about 1/4 to 1/2 cup of bleach in about 1/2 gallon of water. Any other tips would be appreciated as I'm just a rookie at this. :)