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There is one thing I'm still confused about. I've always understood that the closer the light source is, the softer it is, and the further away it is, the harsher (and Jim corroborates this above) - but you say that this isn't the case?
I don't know where that would come from. It's pure physics, and I stand by my comments above.
Ok...In essence Robert is right here and I wouldn't dare question his experience, but this is how it was explained to me and at least as I'm learning this, has proven to be true...
Think of the sun.... -BIG- light source....REALLY BIG...and in theory it should be quite soft being such a large light source, but because it is so far away it produces a really harsh light on a day with no clouds. If it's a cloudy day however, the clouds diffuse the light or cause it to "spread out". Now if you were say on Mercury instead of here on Earth -and- you could turn down the intensity of the sun to the same approximate light level as you get here on Earth, as I understand it you would indeed have a much softer light because of it's relative size to your relative position.
I think the issue here simply goes beyond the "distance" of a given light source to the subject. If for example you were to say, take an ordinary light bulb and put it next to any given subject, you would certainly see very harsh shadows (and harsh light respectively) and as you move the light bulb away from the subject, the light gets dimmer and shadows are of course going to "spread out" as the light bulb moves further and further away. -If- this were the only way we were lighting a subject for photography then certainly what Robert says is quite true...and yes, it is basic physics as he suggests. In regards to the light bulb analogy though I would also mention that "different light bulbs will produce different light". In this case a "soft white" bulb is going to produce a "softer light" than say a clear bulb of the same intensity...the clear bulb is going to produce a harsher light with more contrast. Why? Because the "soft bulb" is diffused...the light isn't as directional. It's this directional aspect of light that causes harsh contrast. This is why we use "light modifiers" such as softboxes and umbrellas, etc.. The laws of physics are still the same of course, but here when something such as a softbox is really close to a subject it produces a softer light because it makes the light source "bigger" relative to the subject and of course it also diffuses the light. But as you move it away (assuming you turn up the power of the flash to compensate) the light becomes less diffused because now only a portion of the light is actually hitting the subject and that portion of light is more directional and thus becomes harsher.
Please excuse my really crude diagrams here, but hopefully this will illustrate what I'm trying to explain here...
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In the case of the first diagram, the softbox is closer and because it's large, the lighting is "spread out" across the subject. In the second diagram however,
most of the light that comes from the softbox doesn't actually reach the subject...the light that does is much more directional and as such is much harsher. The issue here is that directional light from a smaller light source is harsher than diffused light from a larger light source.
If you were to use a smaller light source in the first diagram, then yes, certainly the light would be much harsher because the light coming from it that actually hits the subject would be more directional as apposed to being spread out and "made larger" by the softbox. The "quality of light" coming from a smaller light source closer to the subject would be roughly equivalent or roughly proportional to that of a larger light source further from the subject.
Another issue here directly related to your shots is that an umbrella versus a softbox are also going to affect the directionality of light...the parabolic shape of an umbrella is going to effect light differently than a square diffused modifier such as a softbox. They both "spread the light out" but do it in different ways with different effects. In regards to the contrast issues of your shots (which again I really didn't think were too bad personally), I don't think that "moving the light source back" as Robert suggested would have been better as much as "making the light source larger and/or more diffused"
The point here is that in regards to how harsh light is in regards to the subject, "the distance" from the light source isn't the
only consideration...the
size of the light source plays an equal roll as well as how the light source is diffused and all must be considered together (along with the output as well for correct exposure, brigher/dimmer lights with different corresponding apertures again in regards to exposure, the temperature for correct color balance, etc). In other words, as Einstein would say, "It's all relative"

.
Again, I could be very wrong on all of this...I too am just learning this fine art, but that's the way I understand it and so far it's been working for me

. If I've gotten nothing else right here, I know this much is true...directional light = harsh/contrast, diffused light = softer.
Ugly ass can of worms ain't it? LOL!!!
I hope this helps!
Peace,
Jim
"It is horrifying that we have to fight our own government to save the environment. " - Ansel Adams
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