Umbrellas....Help me understand their use.

I just ordered 2 monolights (200ws each) and plan to start with shoot-through umbrellas.I've never used them and need advice.I'd like to be able to do portraits and full-length glamor shots.

Will a larger umbrella(50-60") be more useful in these different situations,or do I need different sizes?I would assume that the distance the monolight is placed from the umbrella is very important regarding the amount of light spread?So,will a large umbrella work by moving the monolight closer or further for different amounts of spread.Or do I use one size and move the entire embrella to get different amounts of coverage?Are there any guidelines,or do I just need to experiment?

I'm sure there are other considerations I'm missing!
For starters should I get a 33" + 43" +60"?Or just a 60"?

Any advice on translucent umbrellas and their use will be greatly appreciated. Thanks!! Fred

The guy who does these videos has one about lighting and modifiers with photo and animation examples. I think episodes 3 through 5 are the videos which covers modifiers but they're all worth a look.

http://www.youtube.com …9pluWiGCE&featu​re=related

Thanks for the link,Patrick!

Unless you need ultra-light and portable then I would use umbrellas that are 43"/45" to 60". The larger the umbrella the greater the coverage and at the same distance from the subject will produce a softer quality of light.

If you need more control from an umbrella then using it as a reflective bounce will give you a bit more control due to the leading edge of the umbrella. When you fire into a shoot through umbrella there is more light that will come out the back and sides as well as more light coming out of the arc of the front of the umbrella.

A shoot through lets you place the light source closer to the subject and the reflective bounce forces you to keep some distance. If you want to light a larger subject area for 1/2, 3/4 or full length shots then you'll need a larger light source with less rapid falloff. A larger umbrella will do a much better job for that.

If you're doing head shots, head and shoulder or even 1/2 body shots you can do it very nicely with a smaller umbrella and a 43 or 45" umbrella is a great tool for that kind of work.

Another option to umbrellas is something like the Photek Softlighter II. They are available in a 46" and 60" version and the really nice thing about the Softlighter is that is sets up like an umbrella with no required speed ring and it's a 3-in-1 modifier in that it functions as a shoot through umbrella, a reflective bounce umbrella and an indirect umbrella softbox or brolly box. It produces very nice light, it's only slightly more than the the cost of a good umbrella and is very versatile.

Thanks,Rob.
That's pretty close to what I was thinking.I found a set with 33,43,60" umbrellas,but am not sure I'd use the smallest one.Being a set,it's cheaper than buying individuals.The Softlighter has been on my radar for a while.It seems to get mentioned a lot in different forums.Thanks!

frule wrote in post #9091748
Thanks,Rob.
That's pretty close to what I was thinking.I found a set with 33,43,60" umbrellas,but am not sure I'd use the smallest one.Being a set,it's cheaper than buying individuals.The Softlighter has been on my radar for a while.It seems to get mentioned a lot in different forums.Thanks!

Sure thing. The 33" isn't useless but it will probably get little to no use compared to the 43" and 60".

Relative Size is what makes light 'soft'. A 30in. umbrella at 3' away is just as soft as a 60in. umbrella from 6' away, proportionally identical in relative size. So absolute size of a larger umbrella (or softbox) gives equally soft light from farther away, which is sometimes needed with larger groups. Since longer distance also means that light falloff due to distance is less, the larger umbrella from farther away is better than using a smaller umbrella closer. For example, with the 60in. umbrella near one end of a group, the light at the closest end which is 6' from the group is diminished -1EV in strength at the other end of the group which is 11' away (5' across the group). But if the 30in.umbrella is 3' away from the near end, it is 8' away from the other end of the group, which puts -4EV less light at the other end of the group!

Good point,Wilt.I hadn't thought about that.Seems like larger has more benefits:more coverage is possible,less falloff as you pointed out,less chance of umbrella being "in frame".