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-   -   Is this flash really TTL? (https://forums.steves-digicams.com/flash-external-52/flash-really-ttl-37419/)

stallen Nov 7, 2004 7:25 PM

I found this user review about the Sony HVL-F32X on epinions.com. Is this information correct?

user writes... "When Sony says TTL, I think it stands for TheyTrulyLie! TTL is supposed to mean Through-The-Lens. That means the CAMERA'S meter should be doing the work. The HVL-F32X does not integrate with the 828 to allow metering through the lens. Instead, it fires a pre-flash to judge how much light it needs. The amount of flash output is being determined by the flash unit, not the camera- just like any other flash you want to look at. Big big disappointment here, this is NOT TTL!!! My little Sunpak 383 does the same thing for less than half the price. If you've ever used a real TTL system before, you'll notice the difference right away."

He is saying that true TTL doesn't need a pre-flash. Is there a flash available for Sony cameras (specifically the Sony DSC-V3) with true TTL available?

Thanks in advance....

KCan Nov 8, 2004 12:08 PM

I think there is a little mixup here.
Quote:

He is saying that true TTL doesn't need a pre-flash.
1) Film TTL metering doesn't need a preflash . With digital camera, this approach is technically impossible (or may be too expensive?), there is no film plane to allow the light to bounce back to the sensor.



Quote:

"When Sony says TTL, I think it stands for TheyTrulyLie! TTL is supposed to mean Through-The-Lens. That means the CAMERA'S meter should be doing the work. The HVL-F32X does not integrate with the 828 to allow metering through the lens. Instead, it fires a pre-flash to judge how much light it needs. The amount of flash output is being determined by the flash unit, not the camera-

2) Preflash allow the camera do the metering through the actual lens , so saying it TTL metering is not a lie, the camera firmware then determine the amount (duration) of the real flash burst, not the flash unit (as in the case of "auto" mode)





KCan Nov 8, 2004 12:20 PM

uhmm... althrough I am not sure if Sony measure the preflash through the lens or via a sensor in front of the camera :?

Mikefellh Nov 8, 2004 12:26 PM

Pre-flash is to get not only exposure info, but white balance as well (depending on the camera). If it is a dedicated flash, flash and camera are working as one...the camera tells the external flash to preflash and then the camera meters the light.

Who says that if the flash preflashes it is measuring the light rather than the camera??? It's the camera telling the flash to preflash! ;-)

NHL Nov 8, 2004 12:59 PM

While the Sony HVL-F32X has a light sensor on its front, it depends on the camera whether to use this sensor or not!
o In Auto A the camera will command the pre-flash and will meter it Through-The-Lens
o In Auto B the flash itself will do the metering
http://im2.onecall.com/Image_Product...F32Xmanual.pdf

TTL can also mean Transistor-Transistor-Logic which Nikon has used for a long time on its Coolpix family of digital cameras to determine flash control and was never Through-The-Lens as well...

Metz on the other hand claims its 54MZ4/3 flash to be E-TTL compatible with Canon dSLRs when the measurements are actually performed on the flash head and not through the camera lens while achieving a much better consistency as Canon's own units Through-The-Lens! ;)

KCan Nov 8, 2004 7:12 PM

Great info NHL :cool:

NHL Nov 8, 2004 8:51 PM

FYI: http://forums.dpreview.com/forums/re...essage=7540693

minutephotos.com Nov 9, 2004 9:41 PM

Whow, that new Sony flash looks pretty good. I have the HVL -F1000, the difference is it doesn't have the fourextra pins on the bottom. The Sony F707 does not have a smart hotshoe it uses a miniphono plug to connect flash. This new Sony flash is configured just like myy Canon 420EX which definately meters through the lense, and also pre-flashes. Matter of fact I can't stop it from pre-flashing. :sad:

I think TTL flashes server another purpose besides metering. The Sony external flashes shine a pattern that the camera reads ttl to focus in low light. In nightvision mode the flash becomes an ir flashlight which only the lense can see. This allows you to perfectly frame and focus apicture in complete darkness.My experience, espeacially on Sony cameras the external ttl flashes make a big difference.


PS

Thisflashstillhas the ACC terminal minplug cable for older F707, 505v, but the F828 has a smart hotshoe so it does integrate with flash.


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