Totally different flower color after nutrients was added!!

[ghosoff]

Hey everybody I am kinda new to the orchid thing!!! BUt in the last month I have came across 24 orchids which 3 happen to be the same!! I dont know about the 3rd one just yet but the 1st two tha I got changed color after I gave them nutrients and I was wondering just if you guys can explain this to me?? Here are some picture though, and thanks for any help or thoughts given!!

As you can see in the 1st pictures that is what I thought was the normal color, then the 3rd and 4th in the left you can see a little difference and the 5th is up close!! All on the same spike! I more thing can anyone tell me what orchid this is??
I will take some more pictures of it later!