Stofen Diffusers

AndyBorzi

AndyBorzi

AndyBorzi

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I was mucking around in our downstairs toilet (also was used as a dark room in the olden days :p ) with lighting set ups tonight just to see what it was like in a confined space. Anyway, I decided to put on my 420EX Flash to see what I would get. I normally use a Stofen diffuser as a matter of course and have gotten some good photos at weddings. Tonight I took a couple of pics, one with and one without and the difference was almost complete!

Ignore the composition, subject etc but take a look at the difference:

With:




and without:




The 420 flash was pointed upwards towards the low ceiling and a modelling lamp from the studio light was on (tungsten). Can anyone explain why the pictures are so different?

Cheers

AB
 
yup, I did it 3 or 4 times as well to double check. Initially thought it was something to do with the softbox to the right and up abit but just took it down and turned studio light off and get the same results.
 
Interesting, and not something I can explain! :confused:

Were there any other light sources? Perhaps the diffused flash + diffused ceiling meant that there was simply very little light getting to the bottle from your flash - and whatever [harsher] other light there was was taking predominance. Just a guess.

On a side note, your sensor is pretty dirtay :(
 
Perhaps with the diffuser on you are getting light coming from the side (underneath) of the diffuser directly towards the bottle which is producing the reflected highlights whereas without it all the light goes up to the ceiling and the only flash light hitting the bottle is reflected down.
 
freebooter said:
Perhaps with the diffuser on you are getting light coming from the side (underneath) of the diffuser directly towards the bottle which is producing the reflected highlights whereas without it all the light goes up to the ceiling and the only flash light hitting the bottle is reflected down.
Click to expand...

Good thinking! I think you've got it
 
freebooter said:
Perhaps with the diffuser on you are getting light coming from the side (underneath) of the diffuser directly towards the bottle which is producing the reflected highlights whereas without it all the light goes up to the ceiling and the only flash light hitting the bottle is reflected down.
Click to expand...


I think you are right. I fired another test by putting my hand in front of the diffuser and got a very similar picture to the non-diffused flash. That explains the 3 reflections but why the difference in colour temp?
 
Colour temp is easy, the light takes on a hue as it passes through the plastic. Had you not said otherwise, I would have put money on the yellow shots being from the stofen. In fact, I'm still not convinced you haven't mislabelled them. ;)
 
Samiad said:
Colour temp is easy, the light takes on a hue as it passes through the plastic. Had you not said otherwise, I would have put money on the yellow shots being from the stofen. In fact, I'm still not convinced you haven't mislabelled them. ;)
Click to expand...


You've got me doubting myself now! :) No, I am pretty sure I have labelled them correctly!

I was playing around flashing around the house (waits for titters ;) ) with and without the diffuser - I couldn't believe how much distance lost with the diffuser and how better exposed the shots were when I took it off. You live and learn!
 
Make sure you try it in all situations though, you will probably find certain situations benefit from the diffuser, and others won't.
 
Samiad said:
Make sure you try it in all situations though, you will probably find certain situations benefit from the diffuser, and others won't.
Click to expand...


I use it all the time when we do weddings, for outside fill flash. Thats about the only time the flash gets used on my camera. We have only been totally rained off the once and all the pictures were taken inside the church using a combination of studio lighting for the formals and on camera flash (with stofen) for the informals.

I've never had an issue with the stofen, its just last night playing around with it showed me the differences with and without.
 
I would probably say that the white balance comes into it some where, i doubt that there is any way that you could adjust it on the camera but you could easily adjust it in PS :) Might be right, might be wrong :confused:
 
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Samiad said:
Colour temp is easy, the light takes on a hue as it passes through the plastic. Had you not said otherwise, I would have put money on the yellow shots being from the stofen. In fact, I'm still not convinced you haven't mislabelled them. ;)
Click to expand...
The Sto-fen is bright white so wouldn't and doesn't produce a yellow colour cast.
 
AndyBorzi said:
but why the difference in colour temp?
Click to expand...

I think the colour difference is because one shot has light direct from the flash (in fact through the diffuser) and the other doesn't. Light from your flash is going to be pretty close to neutral in colour temp but when relected of the ceiling it will pick up a colour tint. Tungsten light isn't neutral (yellow/redish IIRC) so when there isn't direct flash the colour temp of the light falling on the bottle is going to be different to the default setting your camera is set for ie noon daylight. With the diffuser some light goes direct from the flash and hence doesn't have the colour cast the reflected light does and hence alters the overall mix of light back towards a more neutral colour temp.

pic 1 = tungsten+reflected flash (tinted)+direct flash (neutral)
pic 2 = tungsten+reflected flash (tinted)

I am pretty certain that the diffuser will be made so that it doesn't alter the colour temp of the light from the flash.
 
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