Question about WW2 Army background color for studio photo

[ocsfollowme]

I am working on colorizing this photo for a friend. Any ideas what the studio background color may have been?

 

Thanks in advance,

 

Steve

 

 

[72psb]

Might be a neutral gray. Then all the other tones adjusted to it.

[ocsfollowme]

Might be a neutral gray. Then all the other tones adjusted to it.

 

 

thanks. I looked for several colored studio photos and saw light grey or light blue. The nice thing is that it takes 5 seconds to change it.