Fstop, aperture, shutter speed, etc.

intrinsicanomaly_262dc77de2

I'm a photographer so I do understand what these things mean on a camera, but I can't figure out how they are important in Daz. (rendering in iray) Does it make any difference at all if I render a scene at an aperture of 2.0 versus 12? What about if I set the lumens on the lights to 5,000,000 and then shoot with a shutterspeed of 200,000 versus lumens at 5000 and shutterspeed of 200? (just an example, question being all things being equal in relation to one another, will renders come out the same, take the same amount of time, etc. etc.)?

Fishtales

Whatever you feel happiest doing. As a photographer too I tend to use them as I would using my cameras and set lights to mimic real lights. Most people I would think just fudge it by using settings that suit their render. I have started using the White Balance/Exposure tool to set the Whit Balance occasionally. I don't think there is a right or wrong way to do it, just a different way.

Aabacus

As a (former) commercial photography assistant (the guy that hauls heavy things while the photog makes eyes at the models) I found that the fStop, shutter speed and all the other settings are really a language more than an actual measure. So if you adjust your depth of field with your fStop normally you'd do the same in Daz. Shutter speed has a similar effect but I've not messed with it or ISO. Just play with the settings until you find a language that makes sense to you as @Fishtales notes.

I have been experimenting with using emissives rather than lights. So if a scene, like a basement, has a lightbulb then I use the surfaces selector, click the bulb then browse to the emissive section and set it to a stupidly high value (millions are not rare.) OR you can change the scale and use smaller values. 5MM will become 5k for example.   

I have found the more I use things the way they are used in the real world I get renders that are lit in more realistic ways. You can do whatever you want but it starts to look off and artificial. Good luck! 

Richard Haseltine

The fStop in Render Settings does not affect depth of field, and the fStop in the camera settings does not affect exposure. Shutter Speed can be adjusted without introducing motion blur (sadly), and ISO does not add noise.

JonnyRay

Richard Haseltine said:

The fStop in Render Settings does not affect depth of field, and the fStop in the camera settings does not affect exposure. Shutter Speed can be adjusted without introducing motion blur (sadly), and ISO does not add noise.

This is why (despire being a photographer myself prior to getting into 3D) for adjusting exposure, I find it's just simpler to use the Exposure slider than the individual settings. There's no tradeoff to worry about like there is for a camera and you can go crazy trying to chase settings and attempting to figure out what the right balance is when the end goal is just to end up with an image that is exposed the way you envision it.