What a camera needs to see fade along the roll on a cosmetics carton
You must be able to compare the same solid at the start of the roll and later. If you cannot see it, change the light or the resolution first. Do not loosen the threshold first.
You must be able to compare the same solid at the start of the roll and later. If you cannot see it, change the light or the resolution first. Do not loosen the threshold first.
If you cannot see it, change the optics first
The whole plate gets lighter together, and it grows clearer as the run goes. If the picture cannot separate it at all, moving the threshold only paints the brand colour on the cosmetics carton as a field of red. You must be able to compare the same solid at the start of the roll and later.
Optics
| Needed | Enough looks like | Not enough looks like |
|---|---|---|
| You must be able to compare the same solid at the start of the roll and later. | The whole plate gets lighter together, and it grows clearer as the run goes. | Only a blurred circle left |
| About 3 pixels across | It shows steadily | It comes and goes, yet you write that it can be detected |
| The brand colour is in the field of view | The critical place is seen | The light only hits the decoration edge |
Try it on a sample sheet
- Confirm the picture can separate this: The whole plate gets lighter together, and it grows clearer as the run goes.
- Count about how many pixels it covers.
- If you cannot see it clearly, change the light or the focus. Do not change the threshold.
