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I just added a rather controversial post to my blog regarding incorrect information in popular books . If anyone has anything to add to it let me know .
Basically I feel that if someone is selling a book with photography information in it then the information must be correct or we are being ripped off ! It also makes it difficult to learn about things like flash when we are being taught the wrong things about it by professionals !

Desmond, your blog was a good read.
I wouldn't say the guy in the book is completely wrong, but it really depends on the circumstances to use your flash as a fill flash.

Your example may verify that pointing the flash at 45degrees with bounce card does not give subject a correct exposure, however you are almost shooting direct backlit, your foreground subject already has a very strong contrasting shadow, you are correct, using the flash as described by author will not work in this situation.

However, when its slightly overcast, or when you are not shooting direct backlit situation, what the author has demonstrated will work. Sometimes you just need just a tiny amount of flash to take away the shadows etc on the subject without giving the overall picture a "flashy" look.

Hope you don't misunderstand me, but what I am saying is that it really depends on the application of fill flash. Thats just my input.

Here are my 2 raw examples demonstrating the 2 fill flash techniques:

1. Fill flash with bounce card and flash head pointing up:


2. Fill flash direct at subject:

(02-20-2010 08:31 AM)DRAW Wrote: [ -> ]Desmond, your blog was a good read.
I wouldn't say the guy in the book is completely wrong, but it really depends on the circumstances to use your flash as a fill flash.

Your example may verify that pointing the flash at 45degrees with bounce card does not give subject a correct exposure, however you are almost shooting direct backlit, your foreground subject already has a very strong contrasting shadow, you are correct, using the flash as described by author will not work in this situation.

However, when its slightly overcast, or when you are not shooting direct backlit situation, what the author has demonstrated will work. Sometimes you just need just a tiny amount of flash to take away the shadows etc on the subject without giving the overall picture a "flashy" look.

Hope you don't misunderstand me, but what I am saying is that it really depends on the application of fill flash. Thats just my input.

Here are my 2 raw examples demonstrating the 2 fill flash techniques:

I totally agree with using fill-flash outdoors and I use it as well . But you can simply dial back the flash power to get subtle fill flash without pointing the flash sideways and wasting 99% of the power .
When the flash head is pointed sideways you get less than 1% of the light - and it is still direct flash from the reflective card and flash head because it is not bouncing off anything .


In this image the flash was dialed back "-1" , I could have dialed it back more if I wanted more subtle flash - there's no need to blast most of the flash into space when you can dial it to -3 and use the light more efficiently .



If you do some tests you will find that in your first image the flash would have had to fire at full power considering the distance they were at , and it would fire brighter if it could . You could achieve the same result at TTL/BL -3 and use less than 1% of that power so why fire upwards and use 100X the battery power ?


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I've both books on my desk.

How dare you say Joe McNally is wrong, he's the Nikon flash god! okay kidding, yes you are right, even Joe McNally makes mistakes too.

I've noticed a lot of mistakes in almost every photography book and the beginner books usually have more mistakes! I still got half a dozen photography books on my desk that i haven't read yet, so I'll let you know when i find any mistakes in these books!.

Re fill flash: yeah the only reason you point the flash upward/sideways is to bounce some lights off the ceiling/wall to make your light source become bigger and therefore smooth out the flash light, there is no reason to point the flash up/sideways when you are shooting outdoor with no nearby wall/ceiling. The amount of fill flash light should be controlled by adjusting the power output.

(02-20-2010 11:27 AM)yellow15 Wrote: [ -> ]I've both books on my desk.

How dare you say Joe McNally is wrong, he's the Nikon flash god! okay kidding, yes you are right, even Joe McNally makes mistakes too.

I've noticed a lot of mistakes in almost every photography book and the beginner books usually have more mistakes! I still got half a dozen photography books on my desk that i haven't read yet, so I'll let you know when i find any mistakes in these books!.

Re fill flash: yeah the only reason you point the flash upward/sideways is to bounce some lights off the ceiling/wall to make your light source become bigger and therefore smooth out the flash light, there is no reason to point the flash up/sideways when you are shooting outdoor with no nearby wall/ceiling. The amount of fill flash light should be controlled by adjusting the power output.

Joe McNally is a ''professional guesser" based on what I have read in the hotshoe diaries . . If you have enough speedlights and enough time on your hands to keep experimenting you can eventually get it right , and with 30 years of experience that guessing is bound to get more accurate .
Being a successful photographer is first about business sense , second about dealing with people and third about being a good[enough] photographer .... unfortunately the successful photographers are writing the books .

(02-20-2010 11:36 AM)Desmond Wrote: [ -> ]Joe McNally is a ''professional guesser" based on what I have read in the hotshoe diaries .

Yes I agree. But isn't taking photo really just a game of guessing? Everytime we take a photo, we have to guess a lot of things, for example what is the best angle to take the shoot, what lens I should use, what shutter speed, aperture, white balance and other settings would probably give me the result i want and where/how you should place your flash(es) and what settings/modifier you should use...etc

So the difference between a professional photographer and an amateur photographer is that the pros can usually give much better initial guess because of their knowledge and experience. And when facing a challenging situation, the amateurs would struggle to guess the correct solution while the pros with their "professional" guess would be able to solve the problem easier and have the luxury to try some other creative solutions as well.

(02-20-2010 05:01 PM)yellow15 Wrote: [ -> ]Yes I agree. But isn't taking photo really just a game of guessing? Everytime we take a photo, we have to guess a lot of things, for example what is the best angle to take the shoot, what lens I should use, what shutter speed, aperture, white balance and other settings would probably give me the result i want and where/how you should place your flash(es) and what settings/modifier you should use...etc

There is a certain amount of guessing and a fair amount of 'facts' that can be calculated . On page 258 he states that he needed twice the distance for his lights and would therefore need twice the flash power .
That is totally wrong , things like that can be calculated without guessing , due to the inverse square law you will need 4 times the flash power .
As you learn about exposure there are things you can calculate without guessing and the same goes for flash .
When you understand aperture and depth of field you don't need to guess what aperture to use - you can calculate . Shutter speed is also not about guessing - if you want to capture a sports image you don't guess the shutter speed - you know you need a faster shutter speed .
I doubt there are many pros out there that would agree there is much guesswork once you gain understanding .


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the "twice the power" is definitely a mistake. A careless mistake, and a silly one for someone like him who works with flashes everyday.

Re calculate vs guess, yes most of the things can be calculated with formulas, but what i mean by "guess" is a guess based on "knowledge and experience", not a "random guess".

For example, when taking the group photo during a wedding, instead of using a tape measure and a calculator/table to find out the aperture that would give you the required depth of field, the wedding photographer would just guess the distance between himself and the group and guess the size of the group then he would just pick (guess) a aperture without using any table/calculator that he believe is small enough to keep the whole group in focus. A good professional photographer should be able to guess it right easily.

Or when we are taking sports photo, yes we all know we need a fast shutter speed, but how fast? maybe i should start with 1/1000th second because i believe this should be fast enough to freeze the action or maybe i start with a slower speed like 1/60th second because i want to capture the sense of speed. A professional sports photographer can usually pick a shutter speed that is very close to the optimum shutter speed that gives him the effects he want, this is because he can guess a lot better base on his previous experience, not because he has actually measured how fast his subject is moving then do some calculation .

Of course the initial guess is usually not 100% correct and when you are making adjustments to your settings, your adjustment would be based on some laws of physics which may involves a bit of simple calculation, but everything starts with the initial guesswork and if the initial guess is close enough, the adjustment should be very straight forward even for a amateur.

Maybe we could call it an 'educated guess' . yes I agree that we get better at 'guessing' as we learn more but then it is it really guessing if it is based on understanding ? We may guess the exact distance but we understand why we use the settings we do based on that particular guess .
I suppose if we took away 17 of his 18 speedlights he would have to learn to do some calculations
His statement on page 18 about how BL flash works is also totally wrong , it is a 'guess' based on a mis-interpreted understanding of the [ambiguous] manual . Not based on actual tests and proof .

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(02-20-2010 07:42 PM)yellow15 Wrote: [ -> ]the "twice the power" is definitely a mistake. A careless mistake, and a silly one for someone like him who works with flashes everyday.

Re calculate vs guess, yes most of the things can be calculated with formulas, but what i mean by "guess" is a guess based on "knowledge and experience", not a "random guess".

For example, when taking the group photo during a wedding, instead of using a tape measure and a calculator/table to find out the aperture that would give you the required depth of field, the wedding photographer would just guess the distance between himself and the group and guess the size of the group then he would just pick (guess) a aperture without using any table/calculator that he believe is small enough to keep the whole group in focus. A good professional photographer should be able to guess it right easily.

Or when we are taking sports photo, yes we all know we need a fast shutter speed, but how fast? maybe i should start with 1/1000th second because i believe this should be fast enough to freeze the action or maybe i start with a slower speed like 1/60th second because i want to capture the sense of speed. A professional sports photographer can usually pick a shutter speed that is very close to the optimum shutter speed that gives him the effects he want, this is because he can guess a lot better base on his previous experience, not because he has actually measured how fast his subject is moving then do some calculation .

Of course the initial guess is usually not 100% correct and when you are making adjustments to your settings, your adjustment would be based on some laws of physics which may involves a bit of simple calculation, but everything starts with the initial guesswork and if the initial guess is close enough, the adjustment should be very straight forward even for a amateur.

(02-20-2010 08:31 AM)DRAW Wrote: [ -> ]Here are my 2 raw examples demonstrating the 2 fill flash techniques:

1. Fill flash with bounce card and flash head pointing up:

I did some tests yesterday so I had some figures to work with :
In short you are throwing 95% of the flash power into the sky and making your flash 20 times weaker by only using the light from the bounce card . if you were close enough to the subject it would be much brighter but at that distance the flash simply never had enough power to do what it wanted to do . You could achieve exactly the same results by dialing your flash to -4 or somewhere around there .....

I decided to do some tests to see how much light the bounce card and diffuser dome actually throw forward when used . The blog



First I took a picture at iso 200 F16 and 1/500th sec [ my D50 can synch flash at 1/500th ] .



Then I took an image with direct flash at 1/128th power .

That gave me a 'pivotal' calculation point , something to compare with .





I tilted the flash head upwards and pulled out the bounce card - which also pulls out the wide angle diffuser .

I had to take the flash power to 1/8th to get a similar histogram to the first flash image which tells me that it only throws forward 8/128= 1/16th of the flash or 6% .



But the wide diffuser has a flat edge that also throws forward some light so I tucked that away and tried with only the bounce card out .

I had to go almost all the way to 1/4 power , just a little less , to get the same histogram . here it is at 1/4 power . A bit brighter so somewhere between 1/8th and 1/4 would be right .




This shows that the wide plastic diffuser on the SB800 that pops out with the bounce card throws forward almost as much light as the bounce card itself . Part of this could be due to the fact that since it makes the flash spread more it is directing more light toward the bounce card itself to throw forward .


Then I put the diffuser dome that comes with the flash on , and tilted the flash head at 60 degrees as suggested by the manual and found that I had to only go to 1/16th power to get a similar histogram to the 1/128th power direct flash .



128/16 = 8 , 1/8= 12.5 % .

That suggests to me that the diffuser dome throws forward around 12.5% of the total flash output .

These figures are pretty rough and I'm sure they could be refined a little but I think they give a reasonable idea of the amount of light thrown forward by these flash modifiers