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domo
24-02-2010, 7:21pm
Does having a flash head shooting closer to the centre of an umbrella give better quality or is it the same if the flash is firing into the umbrella about 8 inches from centre? dump question i know but thanks if you can help.

DAdeGroot
24-02-2010, 7:28pm
In short, yes.

You want to have the most even coverage of the umbrella you can get.

However, you also don't want to have the flash head too close to the brolly (i.e. position it further down the shaft), as a closer flash won't cover the umbrella as much either.

domo
24-02-2010, 9:34pm
Oh ok thanks very much Dave, ill have a go at making some kind of bracket.

DavidG
25-02-2010, 10:45am
I believe the closer the flash head the less diffused the light will be as it is passing through a smaller area of the umbrella. On the other extreme if the flash is far away the light can be soft but if its too far you may get some spill past the brollie. This may not be a problem if its not in shot or causing reflections off surrounding objects ...

Brodie
25-02-2010, 10:55am
Yeah basically, the closer you put the brolly to your flash, the harder the light will become because your light source is getting smaller..

The more you pull it away from the flash, the softer the light will get, because your light source is getting bigger.

Its pretty hard to get spill outside of a brollie unless your brolly handle/stem is freakishly long.

coolie21
26-02-2010, 8:49am
Any reason why flash/brolly holders don't allow the flash to point at the centre of the brolly? On mine and on many others I have seen the brolly holder is parallel to the flash so the head always aims above the centre of the brolly :confused013

DAdeGroot
26-02-2010, 9:26am
Any reason why flash/brolly holders don't allow the flash to point at the centre of the brolly? On mine and on many others I have seen the brolly holder is parallel to the flash so the head always aims above the centre of the brolly :confused013

A good umbrella bracket has an angled hole for the brolly stem, such that the centre of the brolly should end up close to where the flash head will be pointing. It does mean you need to remember to put the brolly in the right side though ;-)

coolie21
26-02-2010, 10:09am
Thanks Dave. I suspected that my HK brackets might not be up to snuff :(
Can you recommend a good brand?

DAdeGroot
26-02-2010, 10:58am
Thanks Dave. I suspected that my HK brackets might not be up to snuff :(
Can you recommend a good brand?

I'm quite happy with my Manfrotto one (bought to replace a cheaper one that broke when the stand fell over in a sudden wind). They're not cheap though, but are solid. (approx. $80).

ehor
26-02-2010, 3:37pm
Depends also on the zoom you've set on your flash.
IMO bracket plays little part in it.

These were shot with flashes and 43" shoot through umbrellas on cheap brackets (http://www.digitalcamerawarehouse.com.au/prod5673.htm)
*** links NSFW ***
http://blog.edwardhor.com/2009/11/08/first-lingere-shoot/
http://blog.edwardhor.com/2009/11/22/ally/

domo
27-02-2010, 12:04pm
Just got the $80 manfrotto bracket, very solid piece of quality! thanks for all your help, cheers.

Xenedis
27-02-2010, 12:13pm
Does having a flash head shooting closer to the centre of an umbrella give better quality or is it the same if the flash is firing into the umbrella about 8 inches from centre? dump question i know but thanks if you can help.

Yes, you want the flash head centred for an even spread of light.

Also, don't position the brolly too close, as you'll choke the light. You want an even spread which takes advantage of the size of the brolly.

maccaroneski
01-03-2010, 4:08pm
As a test you could set your flash to low power and shoot directly at the umbrella to see if you are using the entire brolly as suggested by John.

Whisky_Mac
02-03-2010, 11:43am
I assume that this discussion relates to shoot through as well as reflective silver umbrellas. The end result from this discussion is that you are able to control the hardness or softness of the light by the distance of the brolly to the flash head and the principal would be the same for shoot through as well as reflective.

DavidB
02-03-2010, 2:14pm
With "shoot-through"/white/diffuser umbrellas you simply want to control how much of the brolly is lit up (and thus how large your light source will appear).

With reflective umbrellas it's all about the angle of the reflection. These typically aren't perfect parabolas, but for a parabolic reflector if the flash was at the focal point then you'd end up with all the light being reflected out in a parallel beam. Depending on the shape of your brolly, the closer/further the flash is to the brolly, the wider/narrower the beam will be. Also because the flash head is typically off to one side, the beam will end up heading off at an angle to the other side.

Set your brolly up in a dark-ish room and have the camera looking at it side-on from the other side of the room. Take a series of test shots with the flash head in different positions, and by looking at the resulting illumination you should get a feel for it fairly quickly. The flash's zoom setting will also affect things. You may decide on a favourite combination of position and zoom.
If in doubt: experiment. It's digital!

ameerat42
02-03-2010, 2:18pm
And if the flash is too far away you will lose intensity, as the light spills past and misses the reflector. Am...