why do you need to be able to take pictures of small things – is it to see exactly what things look like or is it to

Question: why do you need to be able to take pictures of small things - is it to see exactly what things look like or is it to develop an area of science like disease??
- Keywords:
  disease,
  picture,
  science,
  small
Asked by fleurarcher6192 to Mike, Pip, Tianfu, Tim, Tom on 28 Jun 2012.
- Tom Lister answered on 28 Jun 2012:
  
  I think Tim may have a better answer!
- Tim Stephens answered on 28 Jun 2012:
  
  We take pictures of things and them measure how big they are from the pictures.
  
  An example is people who design spray nozzles for pesticides and fertilisers. The droplets need to be just the right size: too small and they drift on the wind and contaminate places where they shouldn’t be, too big and they don’t cover the plants properly.
  Every different chemical comes out of a nozzle differently because it has a different viscosity, so the people who make the chemicals and the nozzles need to tune their machinery and their chemicals to make sure that the droplets are just the right size.

Question: why do you need to be able to take pictures of small things - is it to see exactly what things look like or is it to develop an area of science like disease??