In newbie terms, how would that affect product photography?
Product photography...
Not a massive problem, but it would be a massive problem if you wanted to photograph a live subject, because the exposures would need to be very long.
I had the same conversation with Michael Sewell
http://www.sewellshouse.co.uk/from Burnley....he showed me the difference between the continous lighting (not sure if it was the model you are talking about) and flash for product photography......we took phtos of the same subject with the different types of lighting...basically...I went in thinking continuos was what I needed and came out knowing I would need flash.
In simple terms the difference that I was shown was the distance the lights could be away from the subject and the power of the lights was far greater.....gave a far better finished image.
The problem really isn't about power, with a subject that doesn't move. All that you need to do is to stick the camera on a REALLY solid tripod and, if the exposure takes several seconds, so what? Assuming of course that nobody is moving around, slamming doors or similar, all of which will cause camera shake. It's about controlling the light.
The problem with most continuous lighting is twofold:
1. You can't fit different light shaping tools, to produce different lighting effects - you can if you use the modelling lamp of a studio flash head, because you can simply fit any of the light shaping tools that you would use with flash.
2. You can't control the power output, either you can't adjust it enough, or you can't adjust it at all. On some studio flash heads you can adjust it when using the flash, but doing so dramatically changes the colour temperature, so although that doesn't matter with flash, it's a total no-no when using the modelling lamp as the light source. On the SmartFlash, you can't adjust the power of the modelling lamp anyway.
What does that mean in practical terms?
It means that the only way of changing the relative brightness is by changing the
type of light shaper fitted to the head, or by changing the
distance between the head and the subject. Changing either of those also changes the
quality of the light, so isn't an option - unless all that you're trying to do is to produce low quality illustrative shots.
To make some sense of the power side of it, the Lencarta SmartFlash has an output of 200
Watt seconds. What this means is that it puts out the same amount of light during its very brief flash as a continuous light of 200
Watts would produce in one second. Except that about 2/3rds of the energy is output in heat, rather than light, so a 150 watt modelling lamp would need a 3 second exposure (ish) at f/11 if the flash required f/11 at full power
would have been a good option.
