Help needed on using flash


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hackie

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#3
Originally posted by Bluestrike

Put the Flash into the shoe, aim the camera and press the shutter! :D
i tot u need to on the flash 1st? :dunno:
 

ziploc

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#9
Hmm... FM2 is a manual camera right? Not sure whether it support TTL or not. If not, got to set the SB28 on Auto mode, or do it the good old way - use manual mode.
 

#10
Originally posted by ziploc
Hmm... FM2 is a manual camera right? Not sure whether it support TTL or not. If not, got to set the SB28 on Auto mode, or do it the good old way - use manual mode.
Right. FM2 has no TTL, so set the SB28 to Non-TTL Auto [A], set a desired aperture on the flash, set the same aperture on the camera, then shoot. Make sure the ISO on the flash and camera matches as well.

Regards
CK
 

zhapchit

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#11
Originally posted by ziploc
Hmm... FM2 is a manual camera right? Not sure whether it support TTL or not. If not, got to set the SB28 on Auto mode, or do it the good old way - use manual mode.
yup fully manual.. and it doesn't support TTL.
So can i still use Auto?
 

ziploc

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#12
Originally posted by zhapchit


yup fully manual.. and it doesn't support TTL.
So can i still use Auto?
Yup you can. Do it like what ckiang described. Set flash to Auto mode, set the ISO, and set the aperture. You'll also need to zoom the flash manually if you are using zoom lens.
 

ziploc

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#15
Oh zhapchit,

Remember to set the shutter speed on the FM2 to the sync speed of the flash too.
 

ziploc

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#16
Originally posted by kamwai
can someone tell me how the ISO and aperture will affect the flash?
Guys, please correct me if I am wrong. A flash's guide number is calculated as follow:

GN = subject distance * f-stop value

The max. GN of a flash unit is usually given for ISO 100 film. So in manual mode using ISO 100, assuming a flash of GN20 (m) and your subject distance is at, say, 2.5m, then

f-stop = 20 / 2.5 = 8

For film speed other then ISO 100, multiply the GN by 1.4 for each stop. So for ISO 400, a GN20 flash will become 20 * 1.4 *1.4 = 39.

You can refer to this page on photozone for more info.

In older flash there is usually a dial at the back of the flash for you to check the setting. You just dial it according to your ISO and subject distance to get the aperture value. Modern flashes with auto mode will automatically calculate the power output according to the ISO and aperture value you set, with the distance it measures from its sensor.
 

#18
Originally posted by zhapchit
Another question ...

if i'm using Auto / Manual mode... how do i use it as a fill flash?
Simple way.

Assuming you are using ISO 100 film, and you are having ambient exposure of 1/125s at f/8.

To have a normal flash exposure, set your flash to ISO 100, f8
To have -1 fill, set flash to ISO 200, f8 or ISO 100, f5.6

Regards
CK
 

Flare

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#20
Originally posted by kamwai
can someone tell me how the ISO and aperture will affect the flash?
In this case, since its not TTL... the flash needs to know how much light to output. The flash need to know the sensitivity of the film and the amount of light that is entering the camera. Then it fires a preflash (I guess) and judge the reflection of the subject and then emitts a flash that should correctly expose the pic taking the sensitivity of the film and the aperture into consideration.

i.e If the aperture is larger, the flash out put should be lower compared to a case where the aperture is larger. And a High ISO film will require less light, so the flash has to emit a lower output.
 

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