Flash for Dummies

Toothie

Toothie

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Ruth
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OK personally and i am sure there are lots of TP members out there in the same boat i am struggling to use a flash correctly.

mostly when ever you ask about flash and how to use it you get links to websites that i am sure contain a great deal of useful information but i can't get my head round it its too much at one time.

So what have i have learn't so far.

1. For fill in flash you expose for the bg and use the flash to light the subject.
2. Pointing the flash away from the subject ie at the celling will reduced shadows.
3. off camera flash can be used to light subjects from different angles.
4. Diffusers will also reduced shadows.
5. if you use a high iso to get a correct exposure for the background and fill flash the subject, the subject wont necessarily be noisy.
6. ETTL uses the light received into the lens to determine the power output of the flash.
7. i need a test shot for all situations using manual flash so as not to over or underexpose.

So do you have any other helpful bits of information regarding flash that can be summed up in a sentence?
 
Toothie said:
2. Pointing the camera away from the subject ie at the celling will reduced shadows.
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I would suggest pointing the camera at the subject would give you a better picture :lol:
 
Toothie said:
6. ETTL uses the light received into the flash to determine the power output of the flash.
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I thought TTL meant Through The Lens, so the camera controls the flash output based on it's light metering ?
 
Guys as amussing as my error was laughing at me is not improving my knowledge on flash photography.
 
The best way is to go out and try some shots using what you know so far. Take a shot using e-ttl and then try the same shot in manual, adjusting the settings until you get a similar result, taking notes as you go.
 
Ruth, not laughing, trying to understand. Point's one and five I'd not heard before and I shall certainly try to remember them.

I'm afraid I don't have any useful additional comments to add, but I'm interested in what others come up with. Thanks for posting them.
 
jgs001 said:
Ruth, not laughing, trying to understand. Point's one and five I'd not heard before and I shall certainly try to remember them.

I'm afraid I don't have any useful additional comments to add, but I'm interested in what others come up with. Thanks for posting them.
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John your comment wasnt there when i typed my response and i ahve corrected the other miss wording you pointed out. :)
 
Guys I'm sorry I have been overly frustrated recently as i have been tiring new things with not as much success as i would like.

I have also learnt i cant post threads and bake cakes at the same time so thanks for pointing out my mistakes will try and remember to proof read as well as spell check in future.

John I am glad you learnt soemthing from the thread.

FITP i know that taking pics will help but the idea for the thread was to share hints and tips so all of us new to flash photography could learn a little at a time.
 
No idea where you got 5 from? But even a correctly flash exposed ISO 1600 will be noisy

7 isn't needed either, depending on what you're doing. ettl fill won't need a manual test for example

I think you're broadly on the right lines there Toothie, so is it your images that you're not happy with then? And in what way?

Flash photography is always a double exposure, the ambient light (even if there is none) and the flash itself. The trick is how you decide to balance, or not, the two light sources

Try to explain a bit more of where you think you have a problem and you may get a better answer :)

DD
 
DiddyDave said:
No idea where you got 5 from? But even a correctly flash exposed ISO 1600 will be noisy

7 isn't needed either, depending on what you're doing. ettl fill won't need a manual test for example

I think you're broadly on the right lines there Toothie, so is it your images that you're not happy with then? And in what way?

Flash photography is always a double exposure, the ambient light (even if there is none) and the flash itself. The trick is how you decide to balance, or not, the two light sources

Try to explain a bit more of where you think you have a problem and you may get a better answer :)

DD
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DD Number 5 i have seen examples of but it migth not always be the case hence the "wont necessarilary" :) and nubmer 7 was refering to manual flash not ettl :)

I not just flash i ahve been struggeling with recently although it hasnt helped. not looking for anything specific just hits and tips. :)
 
Re #5 again - using flash or not will not make any difference to noise if you're shooting at high ISO, flash is not a miracle cure for noise. What you may have noticed is more noise in the shadow areas as the light falls off, but that's not the same thing

Shooting on manual does indeed need a test shot, or 10!, most of the time and especially if you're not also using a light meter. Often, the easiest way to amend the exposure in manual mode is simply to move the flash nearer or further away (assuming the softness isn't an issue)

This sort of stuff is hard to read up on, but easy enough to pick up when you see it done. Try to find U-tube examples of flash at work (I don't know any as I just read it or figured it out anyway - that was before U-tube was invented!)

A day out with someone who knows what they are doing will bring you on leaps & bounds - anyone close you know???

DD
 
DiddyDave said:
Re #5 again - using flash or not will not make any difference to noise if you're shooting at high ISO, flash is not a miracle cure for noise. What you may have noticed is more noise in the shadow areas as the light falls off, but that's not the same thing

Shooting on manual does indeed need a test shot, or 10!, most of the time and especially if you're not also using a light meter. Often, the easiest way to amend the exposure in manual mode is simply to move the flash nearer or further away (assuming the softness isn't an issue)

This sort of stuff is hard to read up on, but easy enough to pick up when you see it done. Try to find U-tube examples of flash at work (I don't know any as I just read it or figured it out anyway - that was before U-tube was invented!)

A day out with someone who knows what they are doing will bring you on leaps & bounds - anyone close you know???

DD
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with regard to number 5 i think we may have miss understood eachother, i mean the noise is less visiable which is what counts imo i know its not a magic cure, my point being with poor iso capability on my camera using the flash alows me to use higher iso as the subject is less noisy than the background.
 
Toothie said:
with regard to number 5 i think we may have miss understood eachother, i mean the noise is less visiable which is what counts imo i know its not a magic cure, my point being with poor iso capability on my camera using the flash alows me to use higher iso as the subject is less noisy than the background.
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Yep - we'll have to agree we don't know what the other's on about - as I still don't get that comment :lol: Maybe I would with an example, otherwise, forget it methinks

No worries

DD
 
I normally steer well away from questions about hotshoe flash because it's incredibly complicated for what it is - but I'll add my 2 penceworth to this one...

1. As previously said, the ambient light and the flash both contribute. The shutter speed affects the effect of the ambient light, the aperture affects both flash and ambient.
2. If you bounce the flash at the ceiling the ceiling becomes the light source. it's bigger so, although the shadows are still there, they are less obvious.
3. Yes
4. Same answer as 2 but to a lesser degree. The diffuser will, to a certain extent, produce softer shadows - but largely because some of the light is bounced off of the ceiling and walls, so if you use it outdoors or in a very large outdoor space you may be disappointed.
5. Wrong. I can see where this idea has come from because in 'busy' areas such as most subjects and in correctly exposed areas the noise is less obvious than in underxposed areas and in areas that have even tones such as backgrounds and skies - but the noise will still be there.
6. In theory, yes. But there are lots of variants of ETTL, some makes work better than others (think Nikon for the market leaders in on-camera flash) and some models of camera will only produce the full effect with certain models of flash - and anyway, it's all a bit hit and miss because the metering system makes assumptions that are by no means always correct.
7. Yes, usually several.
 
Understand the capabilities of your flash: You can't expect it to be powerful enough when bounced off a matt surface over a huge distance when using a small aperture and low ISO. Similarly, its auto capabilities may be lacking when close to a subject with a wide aperture and high ISO.

To illustrate: The manual for one of my flashes states that 10% of the maximum range or 0.7m (whichever is longer) should be used for the minimum TTL range. For a 50mm lens at f/5.6 with 400 ISO, the minimum TTL range works out to be 1.6m while the minimum manual setting of 1/64 full power should give a correct exposure with a full-on flash range of a tad under 2m. You shouldn't blame the flash for overexposed shots at closer range.
 
Ruth I'm no flash expert at all, I do struggle at times but from my limited experience three things have helped me:

1) A diffuser on the flash
2) Bounce the flash (or at least direct away from the subject) I normally point up at between 45 to 90 degrees
3) Set the Flash to ETTL and the camera to manual (f8, 1/125 sec) and let the the camera do the rest

Again I'm no expert and others will have better methods but this has been okay for me :)

I shall read this thread with interest! :D As I need help too!
 
That's an interesting one Dark Star (#3)
I try to consider the scene and aperture setting for the DoF I wanted, whether that be f/2 or f/22 or anything inbetween. If any amount of ambiant light then you can include or not depending on the shutter speed you select (camera in manual).
 
Toothie said:
It seeems that this is a difficult one, no one can seem to agree :lol:
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I think you'll find Garry & I agree all too often :D

There's nothing truly hard about using flash and ambient light, or even flash pretty much as the only light source, it just takes a bit of reading and thought/practise. If you know someone who can help hands-on all the easier

I had no-one to ask for help when I started :(, and when Garry started they hadn't even invented the written word :shake:


:lol::lol::lol:

DD
 
I can only say that way I get my head around flash is to consider your exposure as two images, the part lit by flash and the part lit by ambient light. Lets assume for simplicity sake that your flash is fixed in position and its output can't be altered.

Your ambient is exposed as normal, a combination of shutter speed and aperture.

Your flash lit part of the image is controlled only by the aperture

There in a nutshell is how flash works.
 
subseasniper said:
I can only say that way I get my head around flash is to consider your exposure as two images, the part lit by flash and the part lit by ambient light. Lets assume for simplicity sake that your flash is fixed in position and its output can't be altered.

Your ambient is exposed as normal, a combination of shutter speed and aperture.

Your flash lit part of the image is controlled only by the aperture

There in a nutshell is how flash works.
Click to expand...

True, and as two separate exposures is the best way to consider it... but you can't talk too simplisticly about flash photography. Being able to move the flash, and control it are two more very important variables! You can't always control where the ambiant light is coming from, or its intensity, but you can control the position of your flash, its power and any modifiers to it that you wish.
 
Dark Star said:
3) Set the Flash to ETTL and the camera to manual (f8, 1/125 sec) and let the the camera do the rest

I shall read this thread with interest! :D As I need help too!
Click to expand...

Your camera settings will not be the same always, John (F8, 1/125th) If you use a shutterspeed of 1/125 then your background could look rather dark unless you use a slower speed of perhaps 1/30th or something to lighten it up. You have to expose for the background as if you had no flash on and no subject,,,,,THEN take the photo of the subject and if the flash is in ETTL...then the FLASH sorts the subject out, not the camera!
 
Janice said:
Your camera settings will not be the same always, John (F8, 1/125th) If you use a shutterspeed of 1/125 then your background could look rather dark unless you use a slower speed of perhaps 1/30th or something to lighten it up. You have to expose for the background as if you had no flash on and no subject,,,,,THEN take the photo of the subject and if the flash is in ETTL...then the FLASH sorts the subject out, not the camera!
Click to expand...


Not with the flash in ETTL mode Janice. Even though you may have adjusted the shutter speed and aperture for a desired exposure of the background, when the shot is taken it's the camera that switches the flash off when the subject has had enough light. This is what ETTL is all about.
 
The best website I've found on flash photography is Strobist by an American photo-journalist.
It's largely aimed at off-camera flash but the principles are definitely the same. Have a hunt for the Lighting 101 course for a great ground-up explanation of all this stuff. It's been a huge help to me - I'm working through the Lighting 101 and Lighting 102 courses and now subscribe to the blog updates as well.

He covers stuff like exposure-balancing for a mix of ambient and flash, flash position, diffusion, colour balancing ambient and flash, key lights, and lots more.
 
Toothie..

Try and have a meet with Blinkers, he is local to you and pretty good with a flash these days!!

Failing that, my caravan season opens next week and i'll be down on the Isle Of Sheppy most weekends and i can go through some bits with you, but im no expert! lol..
 
I would recomend tackling this in steps - which is the best way of learning something

Sit someone on a chair, 3 feet away from a white wall in a WELL LIT BRIGHT room

Set camera to 200 iso, shutter speed to 1/60th and leave on apeture prioritory

Shock horror - use onboard flash - look at the results carefully - where arethe shadows - why - what does the skin tone look like? Keep increasing the ISO - see what happens - hopefully everything will look worse and worse

Then use camera mounted flash on automajic TTL or ITL - point the flash straight at the subject - compare the shots - dont bother repeating the ISO experement, but this time go through the range of apetures. what happens - expect the shadow to still be poor, but look at the skin tone and the balance between the lighting in the rest of the scene and the subject (worth repeating this one outside or with the subject infront of a bright sunny window)

Now point the flash at the ceiling - where is the shadow, how big is it, how difuse is it in comparison. repeat, pointing the flash straight up, behind you, on either wall. Essentially what are you doing - you are using the wall like a reflector.. *** hint***

If you can do off camera flash, switch over to manual, set to 1/60th, apeture of f8, and pop flash on 1/4 power and pop the flash ofside the subject - repeat, adjusting the power of the flash untill you get a reasonable result - make a note of the settings. now use a reflector from the other side of the subject, and play with it untill you get a reasonable result..

Essentially what I am saying is - explore the settings one by one, and find out how they actually impact your pictures one by one. I am also saying - take notes - power, settings, distances. Very quickly you will build up a mental map of what your gear does

Report yoru resuls back here! and then read the strobist website!
 
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