Steve's Digicams Forums

Steve's Digicams Forums (
-   Studio Lighting, Flash & Other (
-   -   Sony Alpha Pre-Flash (

bstossel Jan 21, 2007 5:40 PM


New to this forum and using the Sony Aplha DSLR I just purchased. I read the amnual, watched a DVD on the basics of the Sony DSLR A100K and I cannot, for the life of me, find out how to adjust the pre-flash.

I bought this camera for my wife and we use it primarily to take pictures of our 15 month old daughter. She closes her eyes everytime we take a picture because the preflash shoots 5 times before the shot. In 2 months, not one open eye picture.

Please Help!!


Sintares Jan 21, 2007 5:55 PM

Sounds like you havered eye reductionswitched on.

Turn it off under Recording Menu 2

John Maguire Mar 17, 2007 12:05 PM

hi sinatres and bstosseli boughta Sony Alpha 100 and F36 flash unit in early novenber and found that the pre flash is in fact part of the flash metering system and cannot be cancelled, this renders an otherwise excellent camera a very expensive pile of rubbish as not only does it prevent you from trigering studio lights with a slave unit butit also (and more importantly) makes photographing todlers indoors impossible because the pre-flash makes them blink and wou get frame after frame of beautiful pictures spoiled by the fact that the childs eyes are closed and you can't tell an 18mth-2yr old not to blink. i am incredibly angry about this and i am thinking of sending the whole lot back to sony uk.

John Maguire Mar 17, 2007 12:12 PM

if you are planning to take pictures of babies and todlers then do NOT buy a Sony A100 in my experience the pre flash makes themshut their eyesand it can not be cancelled

rinniethehun Mar 17, 2007 12:32 PM

Don't raise the flash?

the Hun

JimC Mar 17, 2007 12:41 PM

You'll find that most modern digital camera use a preflash to help judge the length of the main flash burst needed.

That's because the sensors used in digital cameras are too reflective to meter from like you could to with off the film flash metering. So, the flash systems were redesigned for digital.

In over a year of using a KM Maxxum 5D (which uses the same flash system), I've only seen two people that were sensitive enough to a preflash to blink (and that was only in very dark environments). Now, I probably don't use the built in flash as much as some people. But, I really didn't see it as a big issue when I have used it.

Some people are more sensitive to a preflash compared to others (and the conditions you're shooting in can be a factor).

I've seen complaints from users of other camera models too (Nikon, Canon, Kodak and more) about blinks from a preflash. It happens. Animals are usually more prone to the issue. The KM and Sony DSLR models do have a slightly longer delay compared to some other models. So, I have seen a few complaints from time to time.

But, most people don't even notice that there is a preflash (even the owners of the cameras often don't realize that a very short preflash is happening just prior to the main flash). It's used for metering purposes.

One way around it... use a non-dedicated Auto Thryistor type flash system that has a built in sensor to measure reflected light during an exposure. Then, a preflash doesn't happen. You can get an adapter to give your DSLR-A100 an ISO standard hotshoe for this purpose.

Or, go with a Metz 54MZ4 with the latest SCA3302M7 foot and use it in Auto mode (the Metz has the ability to use it's own built in sensor to elminate the need for a preflash and is aware of your camera settings using it's Auto versus TTL modes).

I spent a total of $48 for a flash system to use with my Maxxum 5D (and that included two external flashes). This solution would also work with your Alpha.

* $16 for a third party adapter to give the 5D an ISO standard hotshoe (and a PC Sync Port).

* a Sunpak 222 Auto with tilt and two aperture ranges for a smaller flash unit (GN of about 72 feet at ISO 100) for $7.00 from (and they even threw in a nice, coiled PC Sync Cord with it).

* a Sunpak 333 Auto with tilt, swivel and zoom head with multiple auto aperture ranges, as well as better manual settings (full, 1/2, 1/4, 1/8, 1/16).

GN runs from 86 feet to 120 feet at ISO 100, depending on the zoom head setting. I got this one for $25 (like new in box in 10 condition from the used department at B&H).

Total Flash System Investment: $48

I just use manual exposure on the camera, setting the aperture and ISO speed to match the Aperture Range selected on the flash and let the flash control the exposure via how much light it sees reflected using it's built in sensor. With a Metz MZ series strobe using the correct foot, you wouldn't even need to do that much (since it would be aware of the camera settings being used). No preflash needed.

JimC Mar 17, 2007 12:52 PM

Moderator note:

Two separate threads on this topic have been merged into this one.

Jim C.

JimC Mar 17, 2007 12:58 PM


...not only does it prevent you from trigering studio lights with a slave unit...
Most digital cameras use a preflash for metering purposes.

Wein makes digital aware slave triggers that can get around this issue if you really want optically triggered slaves.

They're a $39.95 each or $79.95 a 3 pack at B&H:

3 Pack of Wein Digital Slave Triggers at B&H for $79.95

One Wein Digital Slave Trigger at B&H for $39.95

But, I'd probably go with a non-optical solution if I wanted to fire multiple strobes without cords (radio trigger via a hotshoe adapter).

JimC Mar 17, 2007 1:44 PM

1 Attachment(s)
bstossel wrote:

She closes her eyes everytime we take a picture because the preflash shoots 5 times before the shot.
One more comment...Brad, I missed that part (fires 5 times)

Most people are barely able to detect that there's a preflash at all, much less figure out how many pulses there are without using special test equipment.

If you're actually noticing multiple preflashes, you've probably got Autofocus Assist turned on (where it uses the flash to help the Autofocus). That was the very first thing I turned off when I got my Maxxum 5D. It's quite irritating.

Look under your custom menu in your Alpha 100 and make sure AF Illuminator is set to OFF. If it's on, the camera will use the flash for Autofocus assist and fire a series of flash bursts. I think it does more harm than good (the camera focuses well enough in most low light conditions without this "feature").

kberntsen Mar 19, 2007 2:04 PM

Another more expensive approach wouldbe the Metz 54 MZ-4 which I understand you can switch to Auto-Thrystor mode and avoid the preflash.

All times are GMT -5. The time now is 8:05 PM.