Gabriel Lippmann Quotes.
When the shot is afterwards subjected to white light, colour appears because of selective reflection.
This result is due to a phenomenon of interference which occurs within the sensitive layer.
The length of exposure (one minute in sunlight) is still too long for the portrait. It was fifteen minutes when I first began my work. Progress may continue.
I got quite good results from protein plates.
Most of these pictures, taken while travelling, were developed on the mantelpiece of a hotel room, which proves that the method is easy enough to carry out.
The series of photographic operations, developing, washing, final drying, takes about quarter of an hour.
Life is short and progress is slow.
[On the Gaussian curve, remarked to PoincarГ©:] Experimentalists think that it is a mathematical theorem while the mathematicians believe it to be an experimental fact.
The plate at each point only sends back to the eye the simple colour imprinted. The other colours are destroyed by interference. The eye thus perceives at each point the constituent colour of the image.