Softening light with umbrella & softbox?

[250Gimp]

I was wondering if I will gain much in the way of softer light by shooting through my umbrella with a lumiquest soft box on the flash?

In Theory I think I will, but I'm sure someone can tell me for sure.

Cheers

 

[Big Mike]

The softness of light is dependent on two things. The size of the source and the distance to the subject.

So if the umbrella is larger than the softbox, then yes, it will make it softer. (than the softbox alone)

There is also the quality of the light to be considered. Things like umbrellas and softboxes may not give you perfectly even light. There might be a hot spot in the centre, for example. This is why some softboxes have two diffusion panels.

So your plan of using both the softbox and the umbrella may improve the quality of the light as well as making it softer. Although, I believe the softness would be the same with the umbrella, soft box or not.

Now, you have to consider that using these modifiers does eat up some light...and if you start 'stacking' them, you may end up with less light than you need....but it will surely make your flash work harder, which eats up batteries and causes longer recharge times.

 

[Mike_E]

No all you would be doing is to further weaken the light.

Softer means bigger in relation to the subject as stated.

 

[250Gimp]

Thanks for the response Big Mike & Mike E.

My understanding is a combination of both statements:

bigger and closer = softer
+ more layers of diffusion in the same situation also help soften the light more.

Maybe I am barking up the wrong tree?

Thanks

 

[Big Mike]

more layers of diffusion in the same situation also help soften the light more.

The way I see it, adding more diffusion will only make it 'softer' if the consistency isn't even (ie: if it has a hot spot).

For example, if you have a light behind an umbrella (and positioned properly to spread the light into the whole umbrella), the size of the light source (to the subject) is then the size of the umbrella. If you add a softbox to the light (still behind the umbrella) you are not enlarging the size of the light source (in relation to the subject) so you would not be making it softer.

Remember, softness is a factor of size and distance, not necessarily diffusion. If something does not make the light bigger (to the subject) or move it closer, it does not 'soften' the light.

In this example, the light through the umbrella might be more intense in the middle (hot spot)...so the size wouldn't full be the size of the umbrella. The softbox might diffuse that hot spot and thus bring the technical size of the source up to the size of the umbrella...making it a little softer. But IMO, that slight bit softer is not worth the loss of light power caused by the softbox.

 

[250Gimp]

Thanks Big Mike

 

[Mike_E]

Another way of looking at it is to think of whether or not the light gives off a hard or soft shadow.

For example:

The more precise the shadow the harder the light. A bare flash for instance. (basically a single point light source)

The more diffused light -softer- would be sunlight coming through a cloud. The thicker the cloud the less shadow you get. You would think with this example that the thicker the diffuser material the softer the light but actually what you are getting, as Mike said, is a lessening of the hot spot (the sun).