Olympus External Flash Support by Michael Meissner

This page is an attempt to summerize the main options for external flash support on the Olympus C-2100UZ. It should be applicable for other Olympus C-* cameras like the C-2000Z, C-2020Z, C-3000Z, C-3030Z, C-3040Z, C-4000Z, C-4040Z, C-4040Z, C-700UZ, C-730UZ, and E-100RS. The C-2500L, E-10, E-20N, C-5050Z, and C-750UZ have a hot-shoe, and so don't need the bracket or cable. Note, the C-5050Z does not have a TTL port, just the hot-shoe, while the E-10 and E-20 have both. Other Olympus cameras that don't have the TTL port (such as the C-720UZ, the C-740UZ, and the D-* cameras) would only be able to use slave flashes. Please send any mail regarding these pages to olympus@the-meissner.org.

I have a few other pages people might be interested in:


Why use external flash?

There are several reasons why you might want to add an external flash setup to your Olympus C-2100UZ camera instead of or in addition to using the onboard flash:

Summary of flashes

Here is a table of the various flash options mentioned later in this document.

Manufacturer Type Guide
Bounce Swivel Zoom Fill
Adapter Cable Bracket Rough
FL-50 (260101) Olympus TTL 50m (164') yes yes yes no TTL no N/A FL-CB01 (200664) FL-BK01 (200666) $390
FL-40 (200596) Olympus TTL 40m (130') yes yes yes no TTL no N/A FL-CB01 (200664) FL-BK01 (200666) $390
FL-20 (200858) ** Olympus TTL 20m (65') Unknown Unknown no no TTL no N/A FL-CB01 (200664) FL-BK01 (200666) Unknown
54 MZ-3 (0542300) Metz TTL 54m (177') yes yes yes yes TTL no SCA 3202 FL-CB01 (200664) FL-BK01 (200666) $465
32 MZ-3 (0321300) Metz TTL 37m (121) yes yes yes no TTL no SCA 3202 FL-CB01 (200664) FL-BK01 (200666) $310
32 Z-2 (0321200) Metz TTL 37m (121) yes yes manual no TTL no SCA 3202 FL-CB01 (200664) FL-BK01 (200666) $300
5750DX Promaster TTL 40m (130') yes yes manual yes TTL no 9901 (*) N/A any $215
5550DX Promaster TTL 30m (100') yes yes no no TTL no 9901 (*) N/A any $175
DG-20 DA (58177) Soligor TTL 20m (66') yes ??? no no TTL no N/A FL-CB01 (200664) FL-BK01 (200666) ???
DG-340 (58277) Soligor TTL 34m (112') yes ??? yes no TTL no N/A FL-CB01 (200664) FL-BK01 (200666) ???
20-AF Culmann TTL 20m (66') yes no no no yes no N/A FL-CB01 (200664) FL-BK01 (200666) ???
34-AF Culmann TTL 34m (112') yes no yes no yes no N/A FL-CB01 (200664) FL-BK01 (200666) ???
285HV (233965) Vivitar Auto 37m (120') yes no yes no yes yes N/A FL-CB04 (200661) any $135
283 (233952) Vivitar Auto 37m (120') yes no no no optional yes N/A FL-CB04 (200661) any $120
383 (0383) Sunpak Auto 37m (120') yes yes no no yes no N/A FL-CB04 (200661) any $125
Digi-slave DSF-1 (1300) SR Inc. Slave 24m (79') yes no no no no no N/A N/A any $115
Digi-slave 3000 (1600) SR Inc. Slave 34m (110') yes no yes no yes no N/A N/A any $165
Digi-slave Pro (1200) SR Inc. Slave 37m (120') yes no yes no yes no N/A N/A any $255
34-CS2 Metz Slave 37m (112) no no no no yes no N/A N/A any $135

* For the cameras with a hot-shoe (E-10, E-20, C-5050Z or C-750UZ) you would need adapter 1045 instead of 9901. ** The FL-20 flash does not have an autofocus lamp like the other TTL flashes do.

The explanations for the column entries are:

TTL (through the lens) flashes

The easiest approach to using an external flash on the C-2100UZ is to use a flash that can communicate with the camera, using the information from the lens on (ie, through the lens, or TTL). This also tends to be the most expensive option, costing nearly as much as I paid for the camera for the Olympus solution. Using this solution, the external flash is entirely automatic, and acts like the internal flash does, including using a preflash to set the settings.

Olympus flash

The official Olympus solution is to use a FL-40 flash, coupled with FL-CB01 TTL to TTL cable, and a FL-BK01 flash bracket.

The FL-40 flash was evidently designed for the Olympus C-2500L camera. I think it is kind of hokey that Olympus forces you to buy the bracket, since there are no cable that connects directly from the TTL port on the camera to the flash, you have to connect the cable to the bracket and then put the flash in the bracket's hot-shoe. The E10 and E20 have a hot-shoe on the camera, so that you can by-pass the bracket all together, or use your own bracket with a FL-CB02 cable. The Olympus bracket from the web pictures is a standard L-shaped bracket, which puts the flash to the left and slightly above the lens. The upright post evidently is removable, so that you can position the light by holding it in your left hand.

The FL-40 flash has a guide of 40 meteres (130 feet) at ISO 100, which is the furtherest the light will go in manual mode. Other users report that they can reach 50-60 feet in full automatic mode. The head moves up/down and swivels from side to side to allow the light to be bounced off of a reflector like the ceiling.

Users have measured that the flash in the FL-BK01 bracket is from 2 ¾ to 4 ¾ inches left of the camera, and 8 inches above the lens.

If you have a E-10, E-20, C-5050Z or C-750UZ, the FL-40 flash attaches directly to the hot-shoe, you don't need a bracket. If you want to use a bracket, you would need FL-CB05 Hot Shoe Flash Cable if you wanted to use a generic bracket, or FL-CB02 Hot Shoe Cable if you wanted to use the FL-BK01 bracket. I believe the E-10 and E-20 also have the TTL port, but the C-5050Z and C-750UZ do not.

There is a new flash (FL-20) that is coming out. I don't have full specs on it yet, and it has only been released so far in Japan.

Metz flashes

Metz makes a series of flashes that can take an adapter (SCA 3202) that mimics the FL-40 flash shoe. This means you need to use the FL-CB01 TTL to TTL cable, and a FL-BK01 flash bracket along with the flash and the adapter unless your camera has an Olympus hot-shoe. The Metz website lists the flashes that used the adapter include:

* The 45, 50, 60, and 70 series of flashes are handle mounted, which would probably be awkward since you need to use the Olympus flash bracket as well. The 32 and 54 series would seem to be the appropriate flashes to use.

** The 40 MZ-3i and 40 MZ-1i flashes don't appear on Metz's main site anymore. Presumably they are no longer in production.

Promaster Flashes

Promaster makes a series of flashes that can take one of two adapters for Olympus cameras. The #9901 adapter plugs into the 5-pin TTL socket directly, which eliminates the need for any other cable and you can use any bracket you prefer. The #1045 adapter provides an Olympus hot-shoe, and for the C-2100UZ would need the FL-CB01 TTL to TTL cable, and a FL-BK01 flash bracket. The #71177 adapter should allow you to use the flash as an automatic flash, driven by a hot-shoe or pc-sync cable (ie, using the FL-CB04 cable). The promaster digital flashes include:

Soligor flashes

Soligor is advertising Olympus hotshoe flashes, DG-20 DA and DG-340 DZ. At this point I don't know anything about them.

Automatic Thyristor and manual flashes

If you don't have a TTL flash, you can use a non-dedicated flash in automatic or manual mode. The only communication between the camera and the flash is the signal to fire the flash. As I mentioned previously, automatic in connection with the flash means that flash adjusts its light automatically (via a thyristor), not that the camera is used in automatic mode.

The usual way to connect these flashes is with a pc-sync cable. You would use an Olympus FL-CB04 cable that connects to the female end of a pc-sync cable, and the male end is plugged into a mono-plug hole in the flash, usually near the hot-shoe connector. A lot of users complain that the FL-CB04 cable does not mate cleanly with the pc-sync cable provided with the flash (either it doesn't connect at all, or it is loose and the cables come apart). In particular, when I bought a cheap Sunpak 144PC flash, the cable did not connect at all, and I wound up buying a Kalimar 175A flash, and discovering that it was the cable that didn't connect and not that the flash was bad. I use a velcro strip arround the two cables to keep them joined, and I've heard of others using rubber bands.

There are flashes that are dedicated to various popular film cameras like Nikon, Canon, Minolta, and Pentex that will not work as a standard auto-thyristor flash. These flashes include:

Flashes that are dedicated to Olympus film cameras, such as the Olympus T-32 will not work as a TTL flash on Olympus digital cameras.

With this setup, you can use any flash bracket you want. If you feel at some point in the future of upgrading to an Olympus or Metz TTL flash, you could use FL-CB01 cable, and a FL-BK01 flash bracket. instead of the FL-CB04, which provides a standard hot-shoe if a TTL flash is not used.

If your camera only has a hot-shoe connector, you can get a pc-sync to hot-shoe converter for a few dollars at any good photo store.

To use an automatic flash, you typically set the flash to one of the builtin settings, and set the ISO level to be that used in the camera (usually locked to be ISO 100). The flash then has a legend that says what f/stop to use, and you set the camera to manual mode, setting that f/stop, and the shutter speed recomended by the documentation. For example, on my Kalimar 175A flash, if I set the control to the blue setting, and set the ISO to 100, the flash indicates to use f/5.6 and has a range of 3-15 feet (with a shutter speed of 1/125 second). If I set it to the red setting, the f/stop is f/2.8, and the range is 10-30 feet. I have my C-2100UZ set so that it remembers the f/stop and shutter speed when in the non-auto modes between power-ups. This means to take a flash, I can usually just dial straight to M-mode and not have to change anything else.

Some really old (or cheap) flashes don't have the thyristor to automatically set the light level, so you would need to use full manual mode. Additionally, there are situations where you need to use manual mode, such as trying to take a picture outside of the range of the sensor, or trying to take a picture that doesn't have a convenient wall behind it to bounce the light back (in which case the thyristor which is reading the reflected light won't be able to judge the distance correctly).

Another advantage of using a pc-sync connection is that you can tie multiple flashes together for a studio setting, using Y-shaped pc-sync connectors that provide 2 outputs for 1 input. For what its worth, I did try a Y-shaped pc-sync connector, and found I could not get the C-2100UZ to fire off both flashes at the same time.

Older flashes (and some modern flashes like the Vivitar 2000) can possibly shoot hundreds of voltages across the flash terminal. If your camera doesn't have the necessary voltage isolation circuits to protect the camera (the E20N has it for instance), a high voltage flash could potentially ruin your camera. I have read that somebody has contacted Olympus regarding flash voltage on the C-2100UZ and was told that it could accept around 24 volts, but I have not talked to them directly. The following web site lists some of the flashes and what their voltages are:


If you find yourself needing to use a flash with a high voltage, Wein makes a product called Safe Sync that reduces the voltage down to 6 volts, which most cameras can tolerate. However, the Safe Sync's are on the order of $40, which is roughly ½ the price of a new flash like the Vivitar 283. The Wein Safe Sync website is located at:


Paramount cords can also make cables with voltage isolation built in. Their web site is located at:


Assuming the voltage is not too high, you have a wide choice of flashes to use. Some popular flashes include:

Slave flashes

A slave flash has no physical connection to the camera, but is fired when it senses the on-board flash firing. This means for instance, it doesn't matter how high voltage your flash is, since it isn't connected to the camera. Also, it means cameras like the 720UZ can use external flash, even though Olympus didn't put in a 5 pin TTL port on the camera.

Many digital cameras, including the Olympus actually fire off the flash twice. The first flash is used to set the distance and the settings, while the second flash is used to take the picture. Many of the slave controllers from film cameras would fire when it received the first flash, and be dark when the camera was actually taking the picture. I have discovered that my Olympus camera seems to fire off one flash when you use it in manual mode or the sports program mode instead of one of the other modes.

Wein has a series of slave controllers that can be set to fire off on the second flash instead of the first. B&H has these available for sale:

Digi-slave flashes produced by SR Inc. can be triggered by the second flash on Olympus cameras. These flashes include:

Metz also makes a digital slave flash, the 34-CS2.

Flash brackets

A flash bracket holds the flash in a fixed position relative to the camera. If you don't need to use the FL-BK01 flash bracket, you could even do away with the flash bracket entirely, holding the flash in your hand. Most photographers tend to use a bracket so they don't have to hand hold the flash. I sometimes feel I should be wearing a pork-pie hat and have a cigarette dangling from my mouth when using the camera in the flash bracket, like the images of the press photographers in movies, particularly from the 1940s, using a large bracket with a medium format camera.

The simplest bracket is just an L-shaped piece of metal with a cold-shoe (ie, a flash shoe that doesn't provide power) on the upgright and a 1/4"-20 screw on the horizontal piece to attach to the camera tripod hole. On these simple brackets (and the FL-BK01 flash bracket), the flash is to the left and above the camera lens when the camera is used in a horizontal orientation. This means that shadows on your subject will be on the right hand side and towards the bottom. If the camera is turned vertically, the flash is still in the same position, which means it will be either on the right side and over the lens (if you turn the camera clockwise), or below the lens and to the left (if you turn the camera counter-clockwise).

Particularly for portraits, many photographers feel that the ideal place for a flash is above the camera, usually around 12 inches or so from the lens. You can get flash brackets that position the flash directly over the lens, and have either the camera rotate or the flash rotate, so that even if you shoot in vertical format, the flash is directly over the lens. The flash brackets which rotate the flash tend to be cheaper and smaller than the brackets that rotate the camera. Rotating the camera is useful if you use a tripod, since the camera will always be mounted directly on top of the tripod, and not on the side with the ball-head turned vertical (which is an invitation for your tripod to tip over). On the other hand, I find a small flash bracket (the Stoboframe Stoboflip) which can fit along with the camera in my bag, allows me to keep the camera mostly ready to take flash pictures, and I don't have to assemble the pieces.

Three companies that make the higher end brackets which flip either the camera or the flash are:

My setup

My first digital camera was an Olympus D-510Z, which is a point&shoot camera that provides no advanced options. I was extremely frustrated by the red-eyes in people and the green-eyes in our cats and dogs with the camera, even when using the so-called red-eye removal option in the camera. So when I was able to upgrade the camera, one of the requirements of the new camera was that it support external flash, and that I purchase the flash when I bought the camera.

The C-2100UZ met my 4 main requirements (high zoom, external flash, manual controls and focusing, and camera + flash fitting within my budget). Unfortuantely all of the stuff was somewhat over budget, and I wasn't able to afford the Vivitar 285HV that a lot of C-2100UZ users mentioned using in Olympus forum of dpreview.com. So I bought a Sunpak 144PC flash which is less powerful. As I mentioned above, the pc-sync cable didn't join with the CB-04 cable, so I eventually got a Kalimar 175A flash from a local camera store, and discovered it was the cable and not the flash.

My first bracket was a generic L-shaped bracket. The screws came out of the cold-shoe about a month after I got the bracket. I then upgraded to the Promaster bracket that a local camera store had that was real solid. My current bracket is the Stoboframe Stoboflip bracket.

After awhile, I decided to upgrade to a TTL flash, and chose the Promaster 5750DX flash. I'll put a review of the flash that I wrote for the Olympus forum of dpreview.com in the next section.

You can see pictures of my equipment on my camera hacks page (hacks as in modification, not as in breaking into computer systems) at:


Review of the Promaster 5750DX

[this is a review of the Promaster 5750DX flash that I wrote for the Olympus forum of dpreview.com, it is edited somewhat from that posting]

When I wrote this flash FAQ initially, nobody else had tried the Promaster flash. I eventually bought the flash and like it.

Promaster is evidently a consortium of independent camera dealers producing their own equipment for sale by their members. Consequently, you won't see Promaster gear at places like B&H photo or Adorama. I bought my flash at Harvard Camera in Harvard, Massachusetts, but their web site isn't real functional. I paid $209 for the 5750DX flash and 5 pin TTL Olympus adapter (#9901), including Massachusetts 5% sales tax.

One place that does sell Promaster stuff on the internet is Precision Camera. I have not dealt with Precision Camera, I just found their link through a search engine, but they look like a reasonable place. They evidently will sell Promaster flashes to Canada. According to this post, Precision will also ship to Australia, though will pay in customs fees, etc.

Another place that sells Promaster flashes is Camcor.com, and also will sell to Canada.

One of the cheapest place that sells Promaster flashes, seems to be Lakeside Camera in New Orleans. I don't believe they are set up for online ordering, but various users have placed phone orders and have been real happy with the results. After I wrote my original review of the Promaster flash, R. Slaughter in the dpreview.com Olympus forum found their prices to be much lower than other Promaster dealers.

Another cheap place that was mentioned in the Sony Forum is Mcalister Camera in Ohio.

The Olympus 5 pin adapter cable plugs directly into the 5 pin TTL hole on the Olympus C & E cameras. You can change adapters, including using adapters for the film cameras, including the adapter that just provides a hot-shoe and pc-sync interface like non-TTL flashes. This means you should be able to use the Promaster flash in a setup with multiple flashes fired off of the pc-sync cable in manual mode. I tried this with a cheap Y connector I bought at the camera store and could not get 2 flashes to fire at the same time. Either flash worked fine, but I couldn't get both to fire off.

The Promaster 5750DX flash has a guide number of 130, which means for TTL mode, you can shoot objects at ~ 50 feet using ISO 100, with f/2.8. The flash offers tilt capability at 90, 75, 60, and 45 degrees to give you some control over bouncing the flash. It does not offer an angle below straight ahead that some flashes offer for macro shots. The flash head can also switch to point behind the camera, so that you can bounce the light off the wall behind you. If you are bouncing the light off of a ceiling or wall, the 5750DX offers a secondary fill light that goes straight ahead.

The flash has a manual zoom arrangement, where you set the the flash head into one of 3 positions (the FL-40 has an automatic zoom, which would be more useful). I was frustrated initially in doing bounce shots off of my 25 foot cathederal ceiling in the dining room, when I discovered I had forgotten to put the flash into telephoto mode. To get a wider angle of light dispersation, there is a diffuser included with the flash. I have not yet tried using the wide angle diffuser, but I probably will shortly, as I just got a wide angle lens.

The flash is certainly bigger and heavier than my old Kalimar flash (which had a guide number of 80). It is roughly 8 inches long, and seems about the same size as the Vivitar 285HZ (which makes sense, since they both are about the same strength). I did discover that it is just the right size for the Lumiquest midi-bouncer that I bought (and was a little to large for the Kalimar :-) It feels to be able the same weight as the C-2100UZ. My Stoboframe Stoboflip bracket seems to be somewhat wobbly with the heavy flash on it (I think a bracket that flips the camera rather than the flash would be better). I have the Promaster L shaped bracket that is sturdy enough to hold the flash, but it doesn't flip the camera or flash.

The flash takes 4 AA batteries, and I use my normal Nimh rechargable batteries in it. I find the flash does not seem to detect when the batteries have enough charge to run the minimal function of the flash, but does not have enough charge to illuminate the subject. It is helpful to automatically review the pictures as you take them if it has been awhile since you changed batteries.

You can set the C-2100UZ into continous mode, and the camera/flash will take multiple pictures as soon as the flash has enough charge. I haven't measured the speed yet in detail, but the speed depends on the amount of light needed by the flash (~ 1 fps for close subjects, ~ 0.75-0.5 fps if the flash is bounced off of the ceiling). Having freshly charged, high capacity batteries is essential if you are going to use continous mode. With one set of batteries (Radio Shack 1600 maH) that may not have been freshly charged, the flash didn't fire on the 6th picture. With another set of batteries that were freshly charged (Energizer 1700 maH), I was able to take continous pictures until the C-2100UZ's buffer filled up.

If the flash doesn't have enough charge to flash, the C-2100UZ shutter release will lock up. I have noticed that the C-2100UZ doesn't notice the flash if you turn the flash on after turning on the camera when displaying the proposed settings to use (but it would use them when it came time to take the flash). I found I had to flip the mode dial forward and back to get the camera to set up for the flash (or always turn on the flash before the camera is turned on). There is a LED light on the flash that indicates TTL mode has been engaged (or in low light situations, if I see the shutter speed is less than 1/30 second). The C-2100UZ does seem to want to use slow speeds like 1/30 for the flash when the ambianent light might indicate to use 1/10 or 1/15, but when the light is darker, it will use 1/125. Since the camera does the same behavior for the onboard flash as for the Promaster, I have to assume it is a design flaw in the C-2100UZ firmware.

The C-2100UZ doesn't seem to record in the EXIF information that it used an external TTL flash like it does for the internal flash.

Even when the C-2100UZ is used in full manual mode, the flash is used in TTL mode. Originally I thought that setting manual mode put the flash into firing with full power, but it doesn't. The camera will vary the power of the flash, based on feedback from the light bouncing off of the subject and background behind the subject.

The flash power adjustment menu on the C-2100UZ does vary the power of the flash. It would be nice if Olympus offered a 1/16 power mode like some of its competitors do.

The Promaster Olympus adapter provides a low light focusing beam to augment the camera's beam (or provide low light focusing on cameras that don't have the light). I took some pictures of my car license plate in complete darkness, and saw the camera could focus to about 40 feet or so.

I've had some problems getting macro mode to be illuminated correctly. I assume part of the problem is the parallex problem where the flash is far enough from the lens that the light the sensor reads is different intensity than the lens sees. For near-macro mode objects, I found bouncing the light off of the ceiling to provide good illumination.

The following table gives the distances in feet that the 5750DX can photograph, using just the main flash, reproduced from the Promaster user manual:

ISO in use Zoom Flash head position
100 200 400 Wide-angle
+ Diffuser
Wide-angle Normal Telephoto
f/1.4 (*) f/2 (*) f/2.8 7 - 57 7 - 75 10 - 84 12 - 93
f/2 (*) f/2.8 f/4 6 - 40 6 - 53 8 - 59 10 - 65
f/2.8 f/4 f/5.6 5 - 29 5 - 38 7 - 42 9 - 47
f/4 f/5.6 f/8 4 - 20 4 - 26 5 - 30 6 - 33
f/5.6 f/8 f/11 (*) 3 - 14 3 - 19 3 - 21 5 - 23
f/8 f/11 (*) f/16 (*) 3 - 10 3 - 13 3 - 15 5 - 16

(*) The C-2100UZ does not support these f-stops.

Flash abuse

Warning, all consumer oriented flashes are not designed for continous use over an extended period of time. I burned out my first Promaster 5750DX flash when I was doing a shoot of storytellers, and took 220 flash pictures in an hour and a half. If you are going to be shooting that much, you should consider studio lighting gear.

Links to other Olympus flash sites

Every so often people grumble about the cost of the FL-CB04 cable, and want to make their own. Here are some links that describe the pin-outs. Note, you are on your own if you follow these instructions. I took the safe way out and bought a FL-CB04 cable:

David Doan posted a link showing how he connected a Sunpak 544 flash, which has a builtin bracket, starting from a FL-CB01 cable:

Camerahobby.com has a nice flash tutorial: http://www.camerahobby.com/Ebook-FlashTechnical_Chapter9Sub.htm.


Michael Meissner, olympus@the-meissners.org