Tips on reducing .bin file size?

[rubylark]

I'm trying to do something clever with my watch face to show a sun from 06:00 to 19:00, and a moon for the rest of the time. To do this I expanded the hour numbers to include my sun/moon pictures. (Essentially I'm trying to recreate the Pebble Time Weather Land watch face, so there are a ton of images).

The preview gif has the exact behavior I want out of the watch face, but unfortunately the bin is now 287kB which is too large to upload to the watch. The .bin size before I expanded the hour numbers was 157kB. I tried exporting pngs without metadata to reduce their file size, but it didn't seem to affect the .bin size at all.

Does anyone know any tips on reducing the bin file size without cutting features? I currently have 86 pngs in the watch face and ideally wouldn't cut any of them.

[TXK]

Cut out the useless and unnecessary parts of each picture.

Make some pictures transparent background.

[rubylark]

In case anyone else reads this with the same problem:

Max .bin file size is 200kB. Images that require dithering bloat the bin file size by A LOT. So converting all images from an RGB color mode to an indexed color mode with just the 8 allowed colors then back to the RGB (because when I was using GIMP, the white index kept being translated as yellow after export; I didn't have that problem with RGB, so I converted it back rather than debugging the cause). Converting to indexed should remove the need for the AmazfitBip Tools to dither the image.

Cropping unnecessary portions of the image into alpha channel also reduced file size.

The biggest problem I was having is that the .bin file size wouldn't update with new iterations. I had to delete then regenerate the .bin file, and then file size would then be reduced.