There are many factors that can affect gram staining procedures, some of them are:
1. The age of bacterial culture: bacterial culture with older cells (more than 24 hours) lose Gram positivity and will appear as Gram-negative.
2. Heat: the application of too much heat during fixation can lead to loss of gram positivity. Excessive heat destroys cell wall. Gram-positive begin to appear as gram negative.
3. Overcrowding of cells: overcrowding of cells is also a factor that affects gram staining procedure, it can lead to improper decolorization. When the cell is overcrowded it affects discoloration, thin smears decolorize faster than thick smears.
It should be what not to do. I wouldnt light a bunsen burner with my hair down
For cameras, an iris diaphragm or optics diaphragm may be used. This allows light to stop before coming in. This function may be necessary if you are taking pictures on a bright and sunny day and you don’t want a glare with your picture. You may turn off the flash, but that may not be enough. Instead, you may need to use the iris diaphragm.
The main function of this part is for the adjustment for the light coming through the abbe condenser. Preferably, you want it to ideally to be in the middle. When you look through the lens, light should be blinding and then this iris diaphragm could be used. Photographers are the experts in knowing exactly how this iris diaphragm works.