Stofen Diffuser

[danielyamseng]

I would like to know when we need to direct flash with diffuser and when to set it 45 deg w/o doing a preshoot?

[Curtis N]

The answer depends on your surroundings and your goals.

Most of the light coming out of the Sto-Fen will come out of the top, with a smaller portion coming out the sides. So varying the angle will alter the amount of light that gets bounced off the ceiling vs. the amount that illuminates your subject directly.

Only experience and an understanding of light will help you make the right judgment in a given situation.

[danielyamseng]

So that mean to be safe I've have to do a pre test before the actual event to get the correct exposure?

I've tried to do a preshoot but the histogram show the graph shift to the left and the intensity is very low no matter what ISO I use and the flash bounce deg.

Also bouncing with stofen would make my subject underexpose and direct flash would wash of the detail.

Setting FEC would make the subject either overexpose or the highlight and shadow lose.

Any advise if just in case my technique was wrong?

[bieber]

If you're getting underexposure, then you need to adjust your FEC, not the positioning of your flash

[danielyamseng]

Here is what I've tried:-

i) Direct flash, FEC -1/3,ISO1600,f4,125 = > underexpose
ii) Direct Flash FEC 0 ISO1600,f4,125 = > hightlight and shadow washout
iii) Direct Flash FEC 1/3 ISO1600,f4,125 = > overexpose.

for all tilt flash setting the subject is underexpose not matter what FEC I set.

If I set FEC to +1, the upper part is slightly over and the legs become underexpose.

FYI, bounce is impossible due to hight ceiling.
I guess stofen can't bounce.

Is this is a limitation of stofen and that I should get a bounce card or probably and DFD ?

[Curtis N]

FYI, bounce is impossible due to hight ceiling.
I guess stofen can't bounce.The Sto-Fen can't bounce if there's nothing to bounce off. It's not a practical choice for high ceilings or outdoor use.

There are few practical alternatives that are a lot better than direct flash, though the Lumiquest Pocket Bouncer, Lumiquest Softbox or Joe Demb Flip-it will create a somewhat larger light source to soften the shadows somewhat.

[danielyamseng]

i)does that mean I really can't a direct flash using stofen?

ii) How's the performance of lumiquest pocket bouncer vs the Joe Demb flip it( Demb diffuser?)

[Curtis N]

i)does that mean I really can't a direct flash using stofen?If you're referring to using the Sto-Fen pointed straight forward, yes you can use it that way. But without close surfaces (walls & ceiling) to bounce the light that gets spread out in all directions, It won't do any good and will wast flash power.ii) How's the performance of lumiquest pocket bouncer vs the Joe Demb flip it( Demb diffuser?)"Performance" is rather vague. I haven't actually used the Joe Demb product so I can't give you an informed comparison. Judging by their designs and customer feedback I'm judging them both to be good products. The Joe Demb Flip-it is mounted to the side of the flash so it can be used with the camera in vertical orientation by swiveling the flash head.

[danielyamseng]

If you're referring to using the Sto-Fen pointed straight forward, yes you can use it that way. But without close surfaces (walls & ceiling) to bounce the light that gets spread out in all directions, It won't do any good and will wast flash power.
that mean stofen still relly one some surface to bounce? if that's the case that's why I'm not getting a satisfactory result?


"Performance" is rather vague. I haven't actually used the Joe Demb product so I can't give you an informed comparison. Judging by their designs and customer feedback I'm judging them both to be good products. The Joe Demb Flip-it is mounted to the side of the flash so it can be used with the camera in vertical orientation by swiveling the flash head.
May I know what diffuser you're currently using?

I'm thinking of getting either joe demb or lummiquest pocket bouncer but unsure which it suitable for me?

[Curtis N]

why I'm not getting a satisfactory result?Questions like that are impossible to answer unless you post a sample image with complete information on exposure and camera settings.May I know what diffuser you're currently using?What you need to understand is, that's like asking a mechanic what wrench he's currently using. A professional chooses the right tool for the job.

I have a Lumiquest Promax System that I can use with or without the white insert. I also have a Lumiquest Softbox. It really depends on the environment. The flash modifier I use most often looks a lot like this.

http://performancephoto.smugmug.com/photos/193799451-M.jpg

[danielyamseng]

Questions like that are impossible to answer unless you post a sample image with complete information on exposure and camera settings.What you need to understand is, that's like asking a mechanic what wrench he's currently using. A professional chooses the right tool for the job.

Then can you advise me on the following situation what flash modifier is suitable:-

i) Studio potrait shoot
ii) Wedding hall - nothing to bounce
iii) Fashion Show which working distance is at least > 15feet
iv) Night club fill with multicolor spot light
v) Stage performance - working distance from 3 feet
vi) Concert - > working distance fr 30 feet



I have a Lumiquest Promax System that I can use with or without the white insert. I also have a Lumiquest Softbox. It really depends on the environment. The flash modifier I use most often looks a lot like this.


Hm, seems like a DIY bounce card:).

I heard that if the subject is far away, it mades no different whether a flash modifier is used or not. Just how far this theory is true?

Lastly I just can't get it how does a bounce card place on top of the flash are able to simulate ceiling bounce?

Isn't it the flash light travel straight ahead unless a wide angle lens is used?

Just wondering how the amount of light being bounce by the flash card can reach the subject and the max working distance of the setup?

[Curtis N]

i) Studio potrait shoot
Studio lighting is a whole different world, with tons of available lights, modifiers and other gear. Entire books have been written on it.
ii) Wedding hall - nothing to bounce
Lumiquest Softbox, Promax w/ white insert or Pocket Bouncer
iii) Fashion Show which working distance is at least > 15feet
I've never been to a fashion show.
iv) Night club fill with multicolor spot light
Depends on the ceiling. Most of those places have dark ceilings so I would refer to my answer under ii).
v) Stage performance - working distance from 3 feet
No flash. I try to avoid flashing performers of any kind.
vi) Concert - > working distance fr 30 feet
Same as v).
I heard that if the subject is far away, it mades no different whether a flash modifier is used or not. Just how far this theory is true?Always be wary of such generalities. Just understand that increasing the distance from flash to subject will reduce the apparent size of the light source.how does a bounce card place on top of the flash are able to simulate ceiling bounce?It doesn't simulate ceiling bounce. It enhances it. If you want ceiling bounce, aim the flash at the ceiling. If you want to enhance this with a bit of direct illumination to brighten eye sockets and create catchlights, then use the card.

This shot was taken with the flash straight up and a simple bounce card. The shadow under his chin is from the light reflecting off the card. Ceiling bounce lit up the background. I used 1/250 shutter speed so ambient light did not contribute. But please note that it was taken in a residential setting with a white ceiling. This is an entirely different approach than I would use in a large room.

http://performancephoto.smugmug.com/photos/225399459-L.jpg

[danielyamseng]

Curtis N thanks for your helpful insight:)

As of my understanding a flash has its working distance at certain ISO.

for ISO 100 24mm working distance is about 15feet.But that's theorytitcally value.

I just wondering why practically no one would really just follow the spec and depending on the lightning condition, a highter ISO is needed.

Anyone can englihten me on this matter?

[Curtis N]

for ISO 100 24mm working distance is about 15feet.But that's theorytitcally value.Whatever your information source is, it's confusing you.

Your working distance depends on
The power of your flash
Flash head zoom setting
Aperture
ISO
Direct flash vs. bounced/diffused

If it's bounced or diffused, it's basically impossible to calculate. There's no way to know without testing how much light is being wasted.

For direct flash, the distance scale on the back of the flash unit gives you an indication of distance range based on all of those factors above.

For bounced or diffused flash, you need to rely on trial and error, and eventually your previous experience in similar settings.

[danielyamseng]

Curtis N thanks fyi . how does the aperture come into play?

[Curtis N]

how does the aperture come into play?The aperture restricts the amount of light that gets through the lens and hits the film/sensor. It affects ambient light and flash the same way.

[danielyamseng]

Curtis, if aparture control the light, is it correct to assume the following:-

i) Say if I currently shooting at 1/60 f4 at ISO1600 with flash to get a correct exposure.

with a lens f2.8, I'm able to get the correct exposure with the same setting and a stop slower ISO(800) ?


Even with high power flash gun, I cannot decrease the ISO(since high power only has a higher GN but if within its working range an 430Ex and 580ex performance is the same) ?

If that's the case then fast prime lens like 50mm f1.4 is the best performer in low light condition?

gee, I guess 50mm f1.4 beat all the way all those fast L lens in low light condition;
not to mention it's sibling 85mm f1.8;)

[Curtis N]

i) Say if I currently shooting at 1/60 f4 at ISO1600 with flash to get a correct exposure. with a lens f2.8, I'm able to get the correct exposure with the same setting and a stop slower ISO(800) ?Correct. In fact, all of the following combinations will result in the same ambient exposure and the same flash range:
f/1.4 ISO 200
f/2 ISO 400
f/2.8 ISO 800
f/4 ISO 1600
f/5.6 ISO 3200Even with high power flash gun, I cannot decrease the ISO(since high power only has a higher GN but if within its working range an 430Ex and 580ex performance is the same) ?I'm not sure what you're asking here. The 580EX has a 35% higher guide number, so it will give you 35% more distance at a given aperture, ISO and zoom setting.If that's the case then fast prime lens like 50mm f1.4 is the best performer in low light condition?Fast lenses have definite advantages in low light, but keep in mind that wide apertures mean narrow depth-of-field. I will often shoot at f/5.6 ISO 400, rather than f/2.8 ISO 100, to get the depth of field I need. But this is the kind of thing you need to evaluate on a case-by-case basis.

[danielyamseng]

I'm not sure what you're asking here. The 580EX has a 35% higher guide number, so it will give you 35% more distance at a given aperture, ISO and zoom setting.
I mean say if using 430Ex I need to use ISO 1600 but with 580Ex I only need to use ISO 800 to get the same exposure. But would that be ?


Fast lenses have definite advantages in low light, but keep in mind that wide apertures mean narrow depth-of-field. I will often shoot at f/5.6 ISO 400, rather than f/2.8 ISO 100, to get the depth of field I need. But this is the kind of thing you need to evaluate on a case-by-case basis.

If let say I prefer to have a wider aparture i.e f4, then what's the advantages of using a fast lense?
i.e say i use 50mm f1.4 set at f4 1/60 ISO 1600 with flash
and another slower lens say 18-55mm set at f4 1/60 ISO 1600 with flash .
what's the advantage of the fast prime lens in this situation?

[Curtis N]

I mean say if using 430Ex I need to use ISO 1600 but with 580Ex I only need to use ISO 800 to get the same exposure. But would that be ?Sort of. The extra power of the 580EX allows the use of a smaller aperture and/or a lower ISO in a given situation. And the difference between those two units is almost one stop.If let say I prefer to have a wider aparture i.e f4, then what's the advantages of using a fast lense? i.e say i use 50mm f1.4 set at f4 1/60 ISO 1600 with flash
and another slower lens say 18-55mm set at f4 1/60 ISO 1600 with flash .
what's the advantage of the fast prime lens in this situation?In general, lenses with wider maximum apertures enable better autofocus performance in low light environments.

[danielyamseng]

Thanks Curtis for your guidance:)

I think I need to do some test shoot in low light condition. But there's lots of combination and unsure how to set up some systematically test so that I can have a ref based of this predefined situation i.e concert lightning, night club, band performance, wedding, church etc.

Is it correct if It start like:-

set 1/60 f4 and ISO start with ISO800 -ISO 1600 and direct flash, tilt 45 deg, direct flash with stofen( effective or not?)
for :-
i) night club (no ceiling to bounce)
iii) Church
iv) concert

testing distance is 15 feets.

[Curtis N]

Experimentation is always a good thing. It's really the only way to truly learn what your camera and flash can do.

I wouldn't use the Sto-Fen unless there's something you want to bounce off. It's just a piece of translucent plastic. Nothing magical about it.

If you're not bouncing off the ceiling or walls, then use direct flash or one of the other products earlier mentioned that create a larger effective light source.

There is a systematic approach to determining the best settings for bounced flash. Read this (http://photography-on-the.net/forum/showthread.php?t=177622), then practice.

[chalkieman]

Can anyone please tell me why I cannot get a picture when I click on the little red 'x' in the posts.
Many thanks,
Alan (chalkieman)

[Psychobiker]

Set your camera to middle point AF @ metering, then put your flash on ETTL and experiment until you find what works best, you'll be able to tell how much power was coming out of the flash (approx), by the noise it makes. If you're taking a dark shot, it will 'puh' with quite some venom.

To see what I mean by 'puh', turn the flash to manual mode, crank it up to 1/1, and press the pilot button. now go to 1/64 and repeat. Note the different noises. I can now make a rough guess as to how much belt came out of the flash

L