The first two don't do anything for me for a few reasons:
1) The subject is dead centre of the frame and the composition is very busy in the background. An environmental portrait would place a bit more emphasis on the environment by changing the camera's perspective and placing the subject in a non-centred location (rule of thirds or something along those lines). The light is decent but the sun could be lower and would have given you a stronger image based on that alone.
2) Again, subject is centred without a really good reason (compositionally). The tree on the left of the image could have been an interesting environmental element and for a basic change you could have moved yourself so that she was on the right third of the frame and then the tree would be on the left third of the frame. Her pose is awkward too... it looks like she needs a washroom. The light is also very harsh and she's squinting. If you have to shoot in direct sun, put it behind your subject so they don't have to squint.
The third image has the most promise, but it's let down by two things - bad focus, and having her left arm blocking her face in the way that it does. You could use her left arm as a framing device for her face but I'd have had her turn a bit more toward the camera with her face. Another idea would be to catch her reflection in the side mirror... a lot of options
They're not bad
photos, but they're not interesting
to my eye...
Hope that helps! Good luck with the film shooting! I've been meaning to do more of that myself lately!
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