Photographs of four different types of bat appeared in a commemorative set on 13 September 2002. I found these by searching for 'photographs' on the US stamp gallery. This one is in my collection.
I never considered that the 2006 Christmas stamps could have been photographs too.
|USA Snowflakes - 17 Oct. 2006|
Physicist Kenneth Libbrecht took photos of two basic patterns of snowflake. Because snowflakes melt so quickly he used a paintbrush to quickly transfer the flakes from cardboard to glass slides where he photographed them in a temperature regulated enclosure, using a digital camera attached to a high resolution microscope.
Until I searched the stamp gallery I had no idea which of my stamps were 'photographs'. Now I shall have to look at other countries. But not for this Sunday-stamps-ii-127.html