Incorrect flash information in books

To make beginners feel better : professionals make mistakes too - but unfortunately sometimes they publish them as well  .
Why do people write photography books ? For the money , not because they want to help people !

{Please note : I am not condemning entire books - just warning about information that could be misleading to a beginner - the rest of the information in the  books mentioned is useful ! }


Many of these people are very knowledgeable about photography but are not necessarily 100% right in all their statements .
As I read through some of the more popular books I see mistakes that could greatly mislead beginners so I thought I would list them here for the benefit of beginners trying to find their way through a sea of [ sometimes incorrect] information .
It's confusing enough as a beginner without reading misleading statements that could further confuse your learning process !

I am busy with this book and on page 18 the author makes the statement about "BL" flash that in this mode " the flash is trying to make the foreground and background roughly equivalent exposure zones " .... that's close to what the manual says which is also ambiguous . Then he goes on to state that if the background is dark it will blow the subject trying to light the background as well  . Nothing could be further from the truth ! In my blog on TTL/BL I explain my tests and how it really works . 

{5/03/2010 :
I've decided to expand on this particular subject since many are questioning my basis for stating that the book's description is totally wrong . The problem lies primarily with Nikon who haven't explained things properly to us .
Page 37 of the SB800 manual describes TTL/BL flash in a very ambiguous way [ I'll go so far as to say the manual is wrong as well in this respect ] ... with regard to TTL/BL "Automatic balanced Fill Flash " it states " The flash output is adjusted for a well balanced exposure of the main subject and background " .... work that one out without getting everyone confused . I started doing tests with TTL/BL flash almost a year ago on Nikoncafe . After many test images [ you can see them on my photobucket album in the "flash" album , most have text on them ] I concluded that TTL/BL only cares about correct exposure on the subject and is far more accurate than TTL flash .
To stick to the subject at hand with TTL/BL it would be more accurate to read : " The flash output level is automatically adjusted for a well balanced exposure of the main subject taking the 'background' or ambient lighting already on it into account " .
As they say "a picture speaks a thousand words "
The author stated that the flash would "arm the photon warhead " and " obliterate the darkness " .. some simple tests will confirm the inaccuracy  of this statement .
To digress slightly TTL flash does this when the subject is smaller than the metering area in the centre of the frame ...

 

Now we go to TTL/BL , due to the fact that it can 'map out' its subject using the matrix metering pattern - and has the advantage of distance info - it is much more accurate :

 So : Did TTL/BL try to obliterate the darkness ? No , it concentrated on the subject . If anyone still doesn't believe me than all you have to do is try it out for yourself and you will see that the statement that TTL/BL will try to light the background is totally wrong .

 So , Never base your statements on something you have read in a manual or heard form someone else - do your own tests and you will learn so much more .... and never make statements in a book based on what you think the manual means - it will get back to you in the end ! } 

The incorrect statement is due to a rather ambiguous statement in the Nikon manual that has been badly misinterpreted . In reality , the wireless CLS that the author praises so highly uses the same metering mode as TTL/BL  ! BL mode will try to get perfect exposure on the subject " and take the ambient[ background] lighting on the subject into account " - that's the balancing part of it .


On to page 258 " I want the light source to be at least twice as far away as I had it , so that's gonna mean twice the power " ..... this is totally wrong , due to the inverse square law  twice the distance means 4X the power ! 
This may have been a genuine mistake overlooked by a hasty review before publishing  - but it's going to have a lot of beginners believing the wrong thing .


The other book I was reading recently ....

 

.... has a suggestion on page 41 about using fill flash outdoors .

 

I have seriously never seen anything so pointless !

How much of the light in this image do you think is going to go sideways .... maybe 1% of 5% ? You'll have your flash firing at full power every shot just to put catch-lights in the subjects eyes , and those catch-lights will be "L"- shaped .

No wonder we have global warming and professionals complain about burning out flash heads ! 

Please note : I agree that fill flash should be used outdoors ! You will do well to follow the advice to use it .... BUT : wasting flash into the air makes no sense when you can simply dial back direct flash for the same results and use less than 1/100th of the power .

 

This weekend I will do some tests to verify the amount of flash that hits the subject with the bounce card .

With outdoor flash you will have the flash dialed down , your working distance will already be greatly reduced and you will hardly notice direct flash at -3 compensation  when used as fill flash .
Why fire the flash at the moon and only get 0.05% of the flash power hitting the subject ? That's one way to fry a flash and waste battery power .


On to the tests :



To give him the benefit of the doubt I stood 6 feet away , he mentioned 8-10 feet .



Just to make sure we were getting the full potential of the flash I set the flash to manual and full power ....



Pretty dismal isn't it [ not the subject! ]

Then I went to TTL/BL -1 direct flash ...



I won't show the picture of my face 2 feet from the camera but when I put the camera in manual at those settings at 1/128th power it tells me I have 0.6m working distance .... with direct flash that is .
At 0.6m [ 2 feet ] with the flash in the suggested position there is still not enough flash at full power .... this suggests that we are getting less than 1/128th of the power from the sideways light using the suggested setup .
You will use more than 150 X the flash power and flatten your batteries more than 150 X faster using this ' technique ' .
I rest my case ... it's a bad suggestion regardless of who made it .

When I buy a camera I expect everything on it to work .
I expect everything in the manual to be correct .
And when I pay for a book of photography knowledge I expect it to be correct .






If anyone has anything to add to this page please let me know !