Specific names will be hard as it is impossible to positively identify hybrids due to the amount of breeding and similarities between some crosses.
The second is a Cattleya and I would venture that the other three are Oncidium intergenerics. 1 and 3 could also be Miltoniopsis; but others may have a different opinion.
If you know where they came from, you can contact the grower.
I think I know all of the names, except the Cattleya!
The first one is called Miltonidium Bartley Schwarz 'White', the third orchid is called Miltonidium Bartley Schwarz 'Highland' en the last one is called Colmanara Masai Red. Is there someone who thinks I'm wrong???
Although Gerben1998 maybe correct, without tags, these orchids cannot be definitely identified. There are just too many hybrids that look startlingly similar.