SX-70 FLASH ADAPTER
The SX-70 flash adapter plugs into the flashbar-slot of the SX-70 and other cameras that use flashbars.
It has a "pc" standard flash contact like most cameras where you can plug in any electronic flash unit.
Use it with your SX-70 to replace Flashbars or for creative effects.
It is also possible to connect a studio flash setup to the adapter to use the SX-70 to test lighting.
The SX-70 gives you a much larger picture area than Polaroid backs for medium- or small format cameras.
NEW ! Which flash works with the adapter? See the flash-list.
Connecting the adapter
- Insert the adapter into the SX-70s flashbar slot, so that the contacts and the components point forward.
- Connect the flash cable of your electronic flash to the pc socket of the adapter.
Troubleshooting: If your adapter does not behave as it should, look
- When there is a flash adapter inserted the camera behaves as if there was
a flashbar present, it goes into flash mode where the aperture is set according
to distance and the shutter goes to a fixed time.
Your electronic flash should have roughly the same light output as a flashbar,
which equals a guide number of 75 at 125 ASA (10 feet at f8 at 125ASA) or a a
metric leitzahl of 25. This is slightly more than the average electronic flash
but you can set the brighten/darken setting to compensate that.
If you have a computer flash turn the computer feature off.
If you are using a TTL-Flash from a modern autofocus camera read its manual if
the flash can be switched into "dumb flash" mode to work with old style
- If you are using the SX-70 with a studio flash setup, remember that the
aperture is f8 for long distances and starts to close rapidly when you focus to
shorter distances than 10 ft.
As the emitted light decreases with the square of the distances and so does the
scattered light from the object, the effective (through aperture) film speed
decreases with the fourth power of distance.
As long as you have the flash on the camera this gives correct exposure.
When you have a studio flash setup you must consider that the effective
filmspeed is 125 ASA at distances of 10 ft or bigger, but decreases to ca 10
ASA at 7 ft.
You can modify your camera so the aperture will always stay at F8 in flash
mode at any distance.
Click here for information about how to modify your
SX-70 so it always keeps the aperture open in flash mode.
The modified cameras will operate like before without a flashbar or adapter
You can also use a computer-flash set to F8 @ 100 ASA with modified cameras.
- You have to remove the adapter from the slot to make daylight pictures.
- Some early model One cameras (Chrome/Leather) refuse to fire the flash when
they think there is sufficient light available to do without. On these models
you may have to cover the electric eye (i.e. with black adhesive tape) if you
want to use the flash to brighten up daylight shots.
This was corrected in Alpha and later models.
- The flash adapter only provides an electrical connection to the flash.
If your camera has a tripod thread you can use a standard flash attachment
rail to mount your flash. You can slightly bend the end of the rail so the
flash points at the same angle as the camera's lens.
If you have an early model with no threads you can either buy a tripod adapter
or make some construction of your own.
Make sure not to obstruct the slot where the picture emerges (Yes it comes out
of the front edge of the bottom!)