basic lighting and lens set up for outdoors portraits

[jpgreenwood]

Today I am taking my teenage daughter to an old ruined castle to get some portrait and modelling shots. Its just a mess about but id like to do a good job. At my disposal i have my Nikon D7200, A 35mm F1.8 prime, a 50mm F1.8 prime (old manual version) and a Sigma 50-150 F2.8.
I have an on camera flash only, but do have a workmans light that will fill the space with directional light. I can tame this with a piece of white paper over the light if needed. It has 3 brightness settings anyway.
I also have a large car windscreen silver reflector that could maybe used to bounce light. Im probably over complicating things and really just want to keep it simple.
I would like a good depth of field, some bokeh (im taking battery fairy lights also) .
Shots will either be against the castle wall or free standing in space.
About late afternoon on a dull day so reduced lighting.
Can anyone advise which lens would give the best results and roughly where i should be putting the off camera light to give the most pleasing shot.
The castle is a simple rectangular open space with no roof and a couple of open doorways and open windows.
Thanks all.

 

[Phil V]

Stick with the Sigma zoom

Don’t bother with the work light, look for the natural light, you might need the reflector but be careful, you can ruin shots with inappropriate light sources.

 

[Andy82]

Don't bother with the camera flash. Any of the lenses will be good if you find the right light. 50mm 1.8 will take a nice portrait as will the sigma if you use it at the higher end of the focal length. Use a reflector.

 

[swanseamale47]

If shes blond the builders light might give a hair backlight and rimlight her, thats assuming the colour matches the daylight. Other than that I probably wouldn't use it unless the light was terrible.