Having some knowledge about aperture, shutter speed and exposure will help you get good results using the Tone Mapping tab on the Render Settings. Like Rich said, in Daz these concepts are applied just like in real life. I always think about taking a picture is like filling a glass of water, the analogy might not be the best but it can help understand said concepts.
Aperture - Is how much you turn the faucet, the more you open it the less time you need to have it open.
Shutter speed - The time you have the faucet open.
Exposure - The imaginary line where the glass is full enough.
Sensor format - Diameter of the glass, bigger the sensor, bigger the glass.
ISO - Height of the glass, in this case the higher the iso value the lower the glass is.
And that's basically it, these concepts are all connected, to adjust one you'll have to think about the other and taking a good picture is the dance between increasing some values and decreasing the others. This probably will confuse you even more but it makes some sense (I think) ahah, just imagine that light is like water running really fast lol.
Also there are some lighting sets available for Daz to get you started. Usually in a photography studio you'll have the basic
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set up. Here you have a bright Key light in front or a bit to the side to give most of the lighting to the subject, a more dim Fill light by the other side to ease the harsh shadows cast by the Key light and then there is the Rim light behind the subject usually opposed to the Key light, this light is very bright and its purpose is to create a very thin line around the model to better define her/his/it's silhouette. I've used a similar setup on my render I posted a few posts back, you can even notice the shadows on the ground and see where the lights are and their intensity.