Pupils different sizes?

[Ange]

I am new to python owing and I have a question about my male Darwins eyes and I can only go off what I have observed in my female so I could be worring about nothing? In the eveings my female has wide pupils which are the same size, she is alert but calm and easy to handle. My male on the other hand has pupils that only open half of the way of my females and most of the time his are different sizes, one may be only a slit while the other is half open, then they will change and the other eye is a slit while the first is half open. He is bitey but will not bite my hand once he is held, its like he isn't worried of being held only scared of any movement, even shadows that come near him after that. Is he ok or am I just being an overworring newbie, please help?

 

[instar]

You could have a vet look at him if your concerned. Pupils dialate or contract according to light levels, dilate wider to allow more light to the retina, contract smaller to limit light to the retina.
Could just be light on oneside (window?) is brighter than the other? What appears uniform brightness to us, may not be so for the snake, our eyes are both focused to the fron so light levels will be much closer to same.
for instance a snake in an enclosure in my loungeroom at night, with enclosure light off, looking toward one end of the enclosure, may have the eye facing the rest of the room, dilated more (light from lamps tv etc) than the one facing darkness at the back of the enclosure. hope that makes sense.
Sensitivity to movement isnt a bad thing for a python, they hunt moving prey, although smell/heat is a larger factor. A python that didnt notice movement, even shadow, would fall prey to something else quickly imo.
Im sure somebody here will be of more help.