This has just occurred to me that when I was a young child, my Mum sent a school photo back and wasn't too thrilled about some of the others because when I was told I needed to smile, I would put far too much effort into it somehow and my face would go all red and I would look pretty stupid with an all tensed up face.
I would either be my normal self as in a straight face (Though I do smile if something makes me happy) or I would be like I described above, as I just did not know how to smile for cameras.
Even today I normally keep my mouth shut and smile because I am not quite sure how to pose. If someone just takes photos and I am relaxed I am more natural so I look good, but if I try to pose I can mess it up.
I have learned to just look as I am and ever so slightly smile (Which comes out as a nice smile I believe).
It is not a big problem like it once was when I was young, but I am wondering. Did others get similar issues?
Do people have to learn how to smile or do they do it automatically if asked?
Another aspect is due to faceblindness, I tend to try to put on a smile all the time because I don't know if people approaching me are people I know, as in the past if someone I know sees me not smiling (As I do not realize that I know them), then I have been told off for ignoring them.... So I then over-compensate and smile at everyone as if I know them which can be quite tiring if one is in a busy place.
Smiling naturally does not take effort, but smiling because I need to (Masking?) actually takes a lot of effort.
Could what I say be common with autism or is it just me and how I relate to things? As I believe that some on the spectrum have to force theselves to smile as they don't do it naturally, but I do it naturally and I do it by force so would this be what allistic people do? (NT's).
It does not really matter as I am me, but it is a question that I would like to know as I am kinda curious...
Going back to the photographs in school, the other children in my class did not seem to have issues except maybe the odd one. I remember being told to smile, and being told off for smiling, and then the photographer and my teacher would say to "Smile properly" but all they had was the same overdone smile with great effort going in... In the end after several minutes of trying and with a whole school of children to do he just took the photo as I was with my interpretation of my very best smile! 
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