Hello to the faithful,
This is Part 10 of my notes and comments on digital cameras for bird
photographers.
In this part I will discuss external flash.
Unfortunately this is another problem area for many consumer class digital
cameras.
During a previous photographic life I experimented with night photography,
especially trying to photograph night birds such as Marbled Frogmouths.
When I 'graduated' to digital photography I looked forward to connecting my
"Metz Mecablitz 45CT-1" (I probably bought it for the name!) along with its
'big-mother' "Televorsatz" flash extender to my Olympus C-700 Ultra Zoom.
(You need really powerful flash for night bird-photography!)
Alas...........I quickly discovered that this digital camera suffered from 3 out
of the 4 main 'flash problems' pertaining to many 'consumer' type digital
cameras.
These are:
1/ The C-700 has no hot-shoe (not that the Metz 45CT-1 needs one but
a lot of standard flash units do). Many of the digital cameras that do have
hot-shoes will be designed for the manufacturer's dedicated flash unit.
Warning: It has been suggested that use of older generic brand flash units, or
even older ones from the same manufacturer, may cause damage to the
camera due to the 'different voltages' involved. This is an interesting theory
and really requires some thought which I will not go into here.
The best thing to do would be to take care when experimenting with
non-recommended flash units.....or better still....don't do it.
2/ The external flash cable socket on the C-700 is designed for the
manufacturer's dedicated flash unit cable and not for 'standard' cables.
3/ The C-700 employs a 'double-flash' system used to set the 'white-balance'. I
believe that this system is used in a variety of models of digital cameras.
4/ Many 'consumer' digital cameras do not even have a cable socket for an
external flash unit.
Another point of note is that some digital cameras do not even have a tripod
screw thread so bracket mounted flash units that will work with that
particular camera can't even be mounted on the camera.
Incidentally, the Olympus C-720 which replaces the C-700 has had the external
flash cable socket removed so not even the dedicated Olympus unit can be used
with this model camera.
Is this what is called an 'upgrade'?
White-balance?
Different light sources are of different colour which is basic photographic
knowledge.
For film cameras different film or special add-on filters are employed to cope
with this.
In digital cameras this is done electronically, either automatically or
manually.
When the internal flash on some, but not all, digital cameras is activated the
camera automatically adjusts the white-balance by firing a short duration flash
a fraction of a second before the main flash.
(Sometimes this can actually be seen with the naked eye. Remember, though, don't
look straight into the flash at close range when you try this out!!)
The white-balance is set during the period of the first flash.
This system of double-flash is not to be confused with the End-of-Millennium
Spectacular that goes under the name of 'Red-Eye Reduction Flash Mode' and
often has human photographic subjects going into a state of apoplexy when
used on them.
The double-flash is often used for ALL flash modes.
This double-flash system prevents the use of conventional slave-activated remote
mounted flash units, the remote unit being activated by the first flash.
Experiments with my own digital camera indicate that the main part, at least, of
the light from the remote flash has dissipated by the time the main flash from
the camera is activated.
A search on the World Wide Web on this subject shows that there are flash units
available that are claimed to overcome this problem by using a system that
'counts' the number of flashes or disregards the first flash.
Unfortunately, the camera dealer where I bought my digital camera has been
unable to track down any such units in Australia.
He tells me that the sales reps he encounters do not list such items in their
inventories.
Other camera dealers I have contacted don't even seem to understand what I am
talking about or why I am interested.
Of course it would be possible to purchase a unit via the internet but I have
seen comments that suggest at least some of these 'delayed flash' remote units
don't actually work the way I would want them to.
Another option for the electronically savvy would be to custom-build a delay
circuit for a remote-switched flash unit.
There is information about this on the WWW if you care to search for it; try
searching on "flash for digital cameras".
So...why don't I use the manufacture's dedicated flash unit?
The following may answer that question......
The dedicated flash unit for my Olympus C-700 Ultra Zoom is the FL-40 which must
be used with the bracket FL-BK01 and the cable FL-CB01.
In Australia the prices for these units as quoted to me early in 2002 where:
Flash unit: $719 (I could get a complete 2 mega-pixel camera for that price!)
Bracket: $129 (Must be very high quality.)
Cable: $92 (I would only want about 30cm and not the whole roll.)
I guess I will have to think of something else.
In the next part to these notes I will discuss:
- other accessories;
- a brief comment on digiscoping
Cheers,
Bob Inglis
Woody Point
Queensland
Australia.
Birding-Aus is on the Web at
www.shc.melb.catholic.edu.au/home/birding/index.html
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