| 1 | source on a bad pixel | 
| 2 | source on a readout streak | 
| 4 | source on a smoke-ring | 
| 8 | source on a diffraction spike | 
| 16 | source affected by Mod-8 pattern | 
| 32 | source within the central enhancement | 
| 64 | source near a bright source | 
| 128 | source near the edge | 
| 256 | point source within an extended source | 
| 512 | weird source (bright pixel) | 
| 1024 | multiple exposure values within photometry aperture | 
| 2048 | the source is too bright (rate>0.97ct/frame) |