a little bitter-sweet thing going on here
Hot Toys may have really captured the correct colors
his inner coat does appear gray, the correct shade as Hot Toys' own
his suit is a dark purple
<a href="https://s197.photobucket.com/albums/aa302/DanielDDJ/?action=view¤t=0dbc74682f0dea8f.jpg" target="_blank"><img src="https://i197.photobucket.com/albums/aa302/DanielDDJ/0dbc74682f0dea8f.jpg" border="0" alt="Photobucket"></a>
<a href="https://s197.photobucket.com/albums/aa302/DanielDDJ/?action=view¤t=f4a1d8a5676ab8ce.jpg" target="_blank"><img src="https://i197.photobucket.com/albums/aa302/DanielDDJ/f4a1d8a5676ab8ce.jpg" border="0" alt="Photobucket"></a>
his shirt also appears to be gray
<a href="https://s197.photobucket.com/albums/aa302/DanielDDJ/?action=view¤t=d49e918275357890.jpg" target="_blank"><img src="https://i197.photobucket.com/albums/aa302/DanielDDJ/d49e918275357890.jpg" border="0" alt="Photobucket"></a>
<a href="https://s197.photobucket.com/albums/aa302/DanielDDJ/?action=view¤t=squeelercw1.jpg" target="_blank"><img src="https://i197.photobucket.com/albums/aa302/DanielDDJ/squeelercw1.jpg" border="0" alt="Photobucket"></a>
in certain lighting, his suit appears to be a Jack Napier purple, but in normal lighting
it's as purple as the Hot Toys one
my suit's colors are as purple as the Movie Masters Joker suit
in dim lighting, it's a like plum, but in sunlight, it can be bright purple
and in bright light conditions
it can be as purple as that poster we've seen where Joker is in the middle of the street
look here
the guys used a combination of sunlight coming from a patio door
and a lamp (possibly used flash for it too)
looks as bright as that poster image
https://forums.superherohype.com/showthread.php?t=304391&page=21