I am one of the traditional 'you need studio strobes, with 250W modelling light' soapbox preachers on POTN, so I'd like to weigh in on this discusson. I will be the first to admit that after I set up with modelling lights, I usually turn them off/down in intensity, because modelling lights, just like 'continuous light' of the past meant
- squintingly bright for the subject,
- yet not intense enough for good shutter+f/stop at limited film ISO'
Now with improved technology, we have
- digital cameras that can support ISO 1600 or 3200 (or higher) at high quality, to overcome limited light intensity
- now LEDs are much more thermal efficient while producing much more light intensity than incandescent
- improved price-performance of LED technology
...and the photographic world is now different (or becoming more so, as the LED technology progresses) because of it.
Past 'continuous light' disadvantage #1 is overcome by the greatly reduced heat of LED. Higher useful ISO in our cameras make it easier to shoot with reasonable shutter + aperture, without #2 and #3. So the greatest disadvantages of past 'continuous' -- as well as modelling lights -- have changed with LED.
I am soon to build my own LED panel to evaluate the technology, and determine if it is close to ready for prime time. I saw LED sources in use probably 15 years ago...it was not yet ready for prime time. It might be close now.
- One significant issue is the color accuracy achievable with not-specified CRI...that may change when the LED manufacturers of the world better realize the importance of that characteristic. I can remember that even 10 years ago, the average CFL did not cite a CRI value either, and now even household CFLs and fluorescent straight tubes list CRI. Hopefully the commercial lighting companies have already solved the CRI issue in selecting LEDs to use in their products...but you pay a premium for that integration. My tests will give some indication about the feasibility of DIY experimentation using blind selection of LEDs.
- As for squinting, I will try with the LED panel at same intensity as 250W-300W modelling lights, and regulate them down until the subject does not have to squint so much, and determine what ISO+shutter+aperture combination works for that level of intensity.
So, back to the OP, the LED constant light source is about to go to one 'judge/jury' (me) and in a couple weeks I hope to post my preliminary opinion. The world of LED in 2017 is very different than it was 15 years ago..its time may have come!