stofen is causing red eye

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joescrivens

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I recently put a stofen diffuser on the end of my 430 ex II but now when I take shots and bounce the flash off the ceiling as I did before without the diffuser I am getting some red eye where I never did before

Am I doing something wrong?
 
Red-eye is quite possible even with a Stofen, if you're at distance and the ambient is low (dilated pupils). At distance, the flash becomes relatively much closer to the lens. Pic?
 
Sorry, what I mean is I never get any red eye without the stofen on, yet do when it is on, how is the stofen now causing red eye?

I'll look for a pic I haven't removed it from, might need to take a new one
 
The stofen is throwing the light in all directions, even though you are bouncing off the ceiling light is still being throw forward to some degree.

Try bouncing is backwards over your head at a nearly vertical setting on the flash head that way you will minimise the amount coming forward.

Nigel
 
joescrivens said:
Sorry, what I mean is I never get any red eye without the stofen on, yet do when it is on, how is the stofen now causing red eye?

I'll look for a pic I haven't removed it from, might need to take a new one
Click to expand...

The only way you will get red-eye is if the light source can be seen directly by the subject, and is close to the lens axis.

Exactly how are you using the Stofen? And how did you have the flash previously?
 
Bouncing off the ceiling, I've always loved the Lumiquest 80/20 bouncer instead of a diffuser. Great piece of kit for this kind of stuff.
 
HoppyUK said:
The only way you will get red-eye is if the light source can be seen directly by the subject, and is close to the lens axis.

Exactly how are you using the Stofen? And how did you have the flash previously?
Click to expand...

The stofen is on top of my 430 ex II and it is pointed directly up. This is exactly how I would use my flash before the stofen, the angle is identical and I always use the flash on manual. I never get any red eye without the stofen but almost always get it with, like this:

4375398462_4074fedd32_o.jpg


you can't see it great there so here is a crop on the right eye

4374653125_2449626278_o.jpg
 
Hilary Briss said:
I have been using the stofen for many years on my wedding work & don't get a red eye problem. Try turning of the AF beam it might be that showing in the eyes, it's worth a try.
Click to expand...

the AF beam? Surely that would happen whether the stofen was on or not. This ONLY happens when the stofen is on
 
I think Shutterman nailed it. Without the Stoffen the flash is very directional, light is directed in effect in a beam at the head angle, where it is reflected and diffused by the ceiling etc. With the Stoffen some light is diffused at source and radiated in all directions, including forward, and red eye is light hitting the rear of the eye, particularity when the pupil is dilated there is always the opportunity of some light to cause some red eye.
Having the flash off axis will help as the light will hit the eye at an angle, or if its not possible and the red eye is a major problem / irritation would it be possible and put a piece of card inside on the forward facing face of the Stoffen, when the flash head is pointed up, a sort of mini gobo; not tried it only a suggestion. Although you might get a shadow.
 
What's the point of using the diffuser AND bouncing? Just take the diffuser OFF when you bounce off the ceiling.
 
Thanks for the suggestion mike. Awp isn't this how the stofen is supposed to be used, nobody uses it to diffuse but actually points it at the subject do they?

I thought the diffusion was nowhere near as much as that with a soft box
 
I've never felt the need to use one - just bounce the open flash off the ceiling. :)
 
awp said:
I've never felt the need to use one - just bounce the open flash off the ceiling. :)
Click to expand...

Doesn't work too well when they are close or the ceiling is high though :(

I use a 'stofen' type diffuser most of the time indoors AND bounce the light off ceilings where appropriate where the diffuser adds fill - I don't get red-eye as the flash is held well away from the lens axis

Simples :D

DD
 
Joe,

That's not redeye. Redeye is when the whole pupil lights up red. What you have there is some fringing at the high contrast boundary between the catchlight and the dark pupil.

This is redeye....

20070602_215049_LR.jpg




p.s. I see you shot that at 85mm. I assume that is the 85/1.8. Purple fringing is a common complaint with that lens, although usually only a problem, sometimes, when wide open. Here's an example of fringing with my 85/1.8 at f/2 (100% crop). I did not use flash but the fringing is very obvious. It's probably a combination of PF from the lens and sensor blooming from a localised overexposure of the sensor....

20091009_214852_4653_LR.jpg
 
Agree with Tim. That's just a normal specular reflection of the Stofen.

If you are using the Stofen as I think you have described it, with the flash head pointing directly upwards, without the Stofen the light source is actully hidden from the subject. With the Sofen, the dome is obviously illuminated and visible.

This how the Stofen works - it diffuses light all around so you get some bounced off the ceiling and walls, and some direct fill-in. With the Stofen, the ratio of bounce-fill is fixed and only varied by the ceiling/walls. In a small room (where I think they work best) a lot of the diffused light is bounced back and provides most of the light, with a nice dash of fill-in. In a big room with a high ceiling, a Stofen does very little compared to direct flash, except waste light. Used outside, the effect is zero.
 
Ok, thanks, it was with the 85mm 1.8 but I also get that effect with other lenses. It makes sense what you are all saying but how come I am the only one who experiences this effect?
 
Well I can only speak from my own experience and I have never noticed a problem when using a Stofen. Here is a random example with with my 17-55 at f/2.8 no edits, shown as a 100% crop.

20080816_222528_7340_LR.jpg


There is something a little bit funky going on there, visible when viewing at 100%, but if you have to view at 100% to find fault then personally I'm not sure it's worth worrying about. I don't think the overall image is harmed in any way by the slight halo around the catchlight. Indeed, for all I know, that's a natural phenomenon within the eye, or it might be a lens aberration. Either way, I'm not bothered by it one bit.

Here's another at f/2.8, this time with my 70-200, unedited, 100% crop. No problem....

20081130_161030_2902_LR.jpg


Sorry I can't be more help.
 
Just guessing here, about the colour fringing on the catch lights.

They are reflections, therefore they would be sharp focused at double the shooting distance. In other words, they are well out of focus and out of focus highlights often exhibit a bit of the lens' natural CA colour fringing.

Maybe? :thinking:
 
Do the eyes look out of focus to
you? They look very much in focus to me
 
joescrivens said:
Do the eyes look out of focus to
you? They look very much in focus to me
Click to expand...

Not the eyes Joe, the reflection is out of focus. Like the image in a mirror. Eg, if you photograph yourself in a mirror 1m away, the sharp focusing distance is 2m.

Therefore, the image of the catchlights is almost certainly out of focus here.
 
HoppyUK said:
Not the eyes Joe, the reflection is out of focus. Like the image in a mirror. Eg, if you photograph yourself in a mirror 1m away, the sharp focusing distance is 2m.

Therefore, the image of the catchlights is almost certainly out of focus here.
Click to expand...

You lost me there. Do you mean inside the eye is a reflection of something and that is out of focus. How do you keep the eye and the reflection in focus? And why does that only happen when I have the stofen on?
 
joescrivens said:
You lost me there. Do you mean inside the eye is a reflection of something and that is out of focus. How do you keep the eye and the reflection in focus? And why does that only happen when I have the stofen on?
Click to expand...

The bright spot you are seeing is a reflection of the Stofen off the surface of the eye. To get that sharp, you would need to focus on double the distance. The eye (cornea) is reflecting like a mirror.

In that respect, being out of focus, it is no different to an out of focus highlight behind the subject, twice the distance away, and it is not uncommon for those to show up with a bit of colour fringing. That's what I'm getting/guessing at.
 
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