Seemolf
Panasonic DMC-FZ5, Sanyo Xacti VPC-E6,
Canon A70,
Nikon FM-2
My offical site is here:
http://www.ki.tng.de/~sgude/
External Flashes for Macros
--- click the pictures to enlarge them in a separate window ----
Summary:
You will find a cheap variation of a popular flash device here.
Giving us an adjustable range of 8 stops and a short flash time of
1/30.000th second.
There are some remarks on internal flashes on my Light page.
Many people talk about slave flashes with the small cameras.
These slaves need the signal of the direct (hard) flashlight.
It is reported that the infrared part of the flashlight can trigger the
slaves too.
Covering the flash wiht an unexposed slide (dia positive) could help in
this case.
Some people consider the use of expensive ring flashes.
This light source is often disappointing because ot the missing shadows.
Any 3 dimensional aspect is missing with these shots.
So leave these parts to the dentists.
Many experienced macrophotographers use only bounced external
flashes (sometimes with slaves).
So lets talk about this equipment!
We need good flashes for our macros- but we have three
problems:
- 1 compatibility of the flash
- 2 availability of light close to the lens
- 3 measuring or adjusting the right power
.....and the price of course.
1 Compatibility of Flashes
First of all we have to test the compatibility.
Digital cameras don't tolerate the high trigger voltages of old flashes.
Traditional cameras used robust mechanical contacts for triggering.
Even these parts could be damaged by the high energies in commercial
use.
Digital cameras changed over to cheap open collector CMOS circuits.
A simple thyristor (costs: some cents!)would have helped us to make our
old flashes compatible.
Old flashes can exceed 200V for triggering - so please be
careful!
These are examples with more than 100V: Metz 34BCT1 and the old Vivitar
283.
Check your manual. The voltage should be below 24V (ISO) or less (canon
EOS 6V).
This is an excellent link, showing the voltages of many
flashes:
strobe
voltage
There are adapters providing a safe power sync (Wein) to your camera.
These connectors are quite expensive (around 70$$).
wein
safe power sync
prices:
wein safe power sync
These solutions are way too expensive!
All you need to reduce the triggering voltage down to 6V is:
- two resistors
- one transistor
- one opto coupler
All this costs less than 5 euros and can be added to any kind of flash:
ct
project, safe power sync (german)
This flash can be used with digital cameras without modification:
I am using external slave triggers for my FZ5, they seem to tolerate
any kind of voltage.
This is: a ROWI slavetrigger - 5$ at fleabay (caution: triggers on
first flash!)
This slave trigger is not compatible to the FZs, it triggers on the
measuring preflash.
The german magazine 'ct published two circuits for this purpose:
ct project, a
simple slave trigger (german)
ct project, a
slave triggering on the second flash (german)
This one can be used with the FZ5.
These small circuits can be used inside the flashes!
Just look at this powerful modified Metz slave:
There are many more instructions on the net....
Here is a nice commercial example from sunpak:
Slave
bracket - Sunpak
This part can trigger on the second flash.
I guess we have solved our triggering problems now.
So let's have a look at my flashes now:
The Sunpak 383 (super) is a very popular adjustable
(!) flash for the bigger FZs:
Its reported voltage (less than 12V) is safe with many cameras
But let's look at another good adjustable flash: Vivitar 283.
- old units (pre '87) up to 200V. My flash is that old version.
- new units (made in china or korea) are safe: below 10V.
My old METZ 34BCT2 can't be used directly too: 211V
This part will "burn" any kind of new camera.
It needs a safe power sync or slave trigger!
2 Availability of Light
There are many ways of bouncing and diffusing.
A simple "omnibounce"
diffusor provides a softer light even in the macro region.
A different way of diffusing: "a softbox"
I have seen an inflatable diffusor (commercial version, not my
"balloon") that looks quite nice.
But we wanted a softer light with bouncing - reflecting
light.
So lets take a look at "lumiquest",
they have many solutions for our problems!
I like this one particularly:"lumiquest_bouncer"
The flash is in upward - bouncing position and some kind of white
material reflects the light.
Here is a nice DIY version from "Brian
L. Zimmermann"
!!WARNING!!
Bouncing and diffusing extend the illuminated region.
Many bouncers "enlight" even the sensor of the flash directly -
resulting in underexposed images.
Solutions to this problem are:
- avoiding automatic funtions
- "shading" the upper part of the sensor or the lower part of the
bouncer
- twisting the head of the flash
- using an external sensor
Sunpak has an accessory for its flashes, that looks like a small sail.
But the easiest way is to fix a bounce card close to the flash in
upward position.
This could look like this one: FZ5 - Metz flash, special sensor
(triggering on 2nd flash),
bracket and wire release
- this is off topic: cheap solutions for the onboard flash:
"-
The $0.03 macro softbox of David F."
..and please have a look at this one!!!!
"-
The smoking hot $0.00 bouncer from monkey.."
..please don't miss the last picture!
This solution is more than a joke. We can't use it for indirect
flashing with our weak flashes.
But I have used this one for "unplanned" macros.
The only problem is, that I don't use the "ingredients"
3 Adjusting the Power
Most of our cameras don't use TTL - measuring through
the Lens
..or if they use it (like the FZ50), the flashes are very expensive.
Some flashes have external sensors that can be positioned close to our
objects.
examples: METZ, Vivitar 283, 285 and some ring flashes.
I will test this sometimes with my equipment.....
But most photographers prefer adjustable flashes with digital cameras.
This explains the popularity of the sunpak 383
flashes.
They have a power switch ranging from full to 1/16 in 5 steps.
The head of this flash can be tilted, this is needed for our bouncing
cards.
I prefer to read the manuals before buying parts.
M. Butkus has collected many manuals here:
Flash
Manuals
This list includes some sunpak and the vivitar flashes!
You will find some sunpak (auto) flashes here.
They are similar to the the 383: eg. my auto 36D.
It is a minolta version, but has full manual functions with my hotshoe.
The expensive Vivitar flashes 283 and 285(HV)can be
controlled in many ways.
- flash trigger - sensor with four ranges
- remote flash trigger
- varipower module from full to 1/32 power in 6 steps
.. and the ingenious Charles Krebs showed us how to refine and expand
this range:
Charles
Krebs - V283
He designed a power module for 8 aperture stops, with half steps!
The literature can help to save some money.
Used flashes can be very cheap today.
eg. my Vivitar 283: 4.5 euros, my Sunpak auto36FD 1 euro ;-) plus
shipment
Both were untested, but functional.
(Trigger voltage of this specific Vivitar 283: 110V - made in: Japan)
By the way, the vivitar 283 needs a special accu holder to use AA
batteries.
This was not included with my toy. My little plate with drilled silver
wires substituted this part.
4 My new adjustable flash
Automatic ranges don't help us with the macros.
The sensor is too far away and there has to be further adjustment.
My Sunpak is ok, but let's look at that second flash.
I did not find the varipower module for the Vivitar 383.
So let's make a new module with the full range: 8 stops, not only 6
(varipower).
Specs:
- non destructive design (I still need the sensor)
- small onboard equipment (C.Krebs' box is too big for mobility).
- 0.5 stops adjustable in a range of 8 (7.5) apertures.
- linear scale for reading.
- reading from the side of the flash.
Looking at the sensor - connector plug:
The sensor can be removed and replaced. It uses only 4 pins.
The connector in the middle is only used by the remote cable,
it can be used to trigger the flash with the remote hotshoe.
A shortcut between the upper left and the contact in the middle
releases the flash.
"Here
is a perfect description of this connector"
Verification: Analysis of the sensor:
You can see the shortcut. This one is needed to activate the hotshoe
connector!
The connector in the middle is not used.
Pin1 and Pin2 are connected to the 200pF capacitor and the light
sensitive part.
This part has two wires. A rotating disk modifies the incomming light
like a set of grayfilters.
Replacing this part with a variable resistor gives us full control over
the flash power and time!
There is a full range available of 8 (7.5) aperture stops and very
short flashes of up to 1/30.000th seconds.
Next step: Analyzing the relation between reduced power and the
resistors
Using the measurements of
Charles
Krebs - V283 www.krebsmicro.com
There is a linear graph on the logarithmic scale.
This means, that a logarithmic adjustable resistor: potentiometer
should have a linear reading!
The prototype: a RADIOHM 100k logarithmic
potentiometer.
One pin is deactivated, the others (take the right ones!) fit directly
into the plugs
Pin1 and Pin2 of the Vivitar 283 flash! - 5mm distance -
Minutes later (no soldering iron needed!) there is a funtional
prototype.
The scale is based on measured resistor values from the table above.
Eureka! linear scale ;-)
The shortcut is a simple wire, covered in this picture.
That's all... All this can be done in 10 minutes!
Total costs:
flash 3 euros (normally around 25 euros)
resistor 0.65 eurocents
The capacitor is missing in this version, I will add it lateron.
I did not need it up to now.
If you need more information on triggering flashes (eg. sound) or high
speed photography:
"Guidebook"
Further Improvements:
- The final version will have a plug system.
- A 470k log resistor could cover the whole range (stops 0 and 0.5 are
missing in my version)
- There will be a commercial looking scale.
- Remote wires will connect an external poti or sensor (only two small
wires are needed).
- A more precise potentiometer could be used - these need 10 turns to
cover the range.
Here are some links of very talented macro photographers using
bouncecards on adjustable flashes with the FZs.
Tan - Tchuanye
Francesco
- Narmer
Bob Frank
Danny - nzmacro
Finally: Using all these parts
There are three options for my flash system now.
- using and modifying the onboard flash
- flashes triggering on the second flash
...with and without using the light of the onboard flash
- mixed triggering - substituting the onboard flash and adding cheap
slaves
Thanks for visiting my pages! Have a nice
day - Sven
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2005-2007 Seemolf last
update 05.may.07 20:00