Really Smart Flashmeter?

[howiepete]

Just acquired a White Lightning strobe and want to use it for tabletop

photos. Have a Minolta Spotmeter F which claims flash reading

capability, but it says to set the shutter speed in the meter (within

the camera's X-sync range), plug the sync cord into the meter, aim the

spot at the area to meter and fire the flash. The readout then gives

the f- stop required for the selected shutter speed. QUESTION: CAN

THIS WORK, since there is no way to input the film speed? How does the

Spotmeter know whether you have B&W ASA 400 or Kodachrome 25 in the

camera? Is a puzzlement!!

[andy_heffernan1]

Well, how does the meter know the film speed when using it to measure ambient light? Any meter has to know film speed in order to recommend an exposure, no matter whether you are using a flash or not.

[skipd]

Another thing that is way off base - with electronic flash, the flash is usually much faster than the shutter speed chosen. Actual shutter speed for flash use is virtually irrelevant except for two things. First, the shutter speed has to be slower than the speed at which the shutter (particularly a focal plane shutter) is not fully open at any time. Second, you might choose to change the shutter speed to vary the effect of ambient light. There is not, however, any real relationship between shutter speed and f-stop for the light generated by the flash as there is with continuous light.

[steve_sivak]

But if you wish to increase the amount of ambient light- thereby changing from

say 1/90 of a second to 1/45, do you not have to close the aperture by one full

stop also? I understand the concept of trying to have approximately 75% of

the light come from the ambient source, but other than reducing flash output I

do not understand how to accomplish it.

[skipd]

Steve - if you wanted to get more ambient light with the same amount of light from the flash, you would only slow down the shutter speed. That would let the ambient light hit the film/sensor for a longer time and increase the exposure.

 

If you wanted, on the other hand, to retain the level of ambient light but reduce the light from the flash, you would both close down the iris and slow down the shutter speed by equal amounts.

 

The flash exposure is not affected by changing the shutter speed (within limits), while the ambient light exposure is affected by shutter speed. The aperture affects both ambient light and flash exposure.

[howiepete]

Hey guys! How about answering my original question? Doesn't a flash meter need to have the film speed input before it can give a sensible reading? My Minolta Spotmeter F manual has no provision for entering a film ASA in describing the use for flash.

[maxz]

<I><BLOCKQUOTE STYLE="border-left: 1px solid blue; margin-left: 0.5em; padding-left: 0.5em;">How about answering my original question? Doesn't a flash meter need to have the film speed input before it can give a sensible reading?</BLOCKQUOTE</I>

Well Andy already answered it in the first posting. Of course it has to if you want to be able to get a EV or shutter/aperture combination that you can use directly without converting it yourself. But, as Andy said, it doesn't matter if it is flash or ambient, the principles are the same.

 

<I><BLOCKQUOTE STYLE="border-left: 1px solid blue; margin-left: 0.5em; padding-left: 0.5em;">My Minolta Spotmeter F manual has no provision for entering a film ASA in describing the use for flash.</BLOCKQUOTE</I>

Are you really sure? It seems very strange. According to what I could find when I quickly Googled was that the Minolta Spotmeter F has an ISO range of 12 to 6400 in 1/3-stop increments.

[skipd]

I just looked up the Spotmeter F on the web, and everything I see shows that it does in fact have the ability to enter the ISO setting (for film or digital cameras). The setting range is 12 to 6400. Here's where I found the specs: https://www.central-camera.com/minolta/spot_f_spx.htm

[steve_sivak]

Skip wrote-

"......if you wanted to get more ambient light with the same amount of light from

the flash, you would only slow down the shutter speed. That would let the

ambient light hit the film/sensor for a longer time and increase the exposure.

 

but now with a slower shutter speed and therefore more ambient light, would

we not get over exposure on the film unless we shut down the lens to

compensate? Why don't I understand this????

 

If you wanted, on the other hand, to retain the level of ambient light but reduce

the light from the flash, you would both close down the iris and slow down the

shutter speed by equal amounts.

 

The flash exposure is not affected by changing the shutter speed (within

limits), while the ambient light exposure is affected by shutter speed. The

aperture affects both ambient light and flash exposure.

[chris_waller]

On the control panel of the Spotmeter F is a button which says ISO/TIME. Press it then set the film speed using the increase/decrease buttons just below it. Once you've setthe film speed then press the ISO/TIME button again to use the meter.

[howiepete]

Thanks to all the smarter photographers here I figured out how to set the film ISO on my Minolta Spotmeter F. Now I have another question. How can I use it with my new White Lightning strobe flash? Setting the Time at different values gives different f numbers using the meter with the strobe, while I am sure that with electronic flash exposure should be independent of shutter speed as long as the shutter is fully open at the time of the flash. Does this mean that this meter can be used only with continuous lighting?

[ellis_vener_photography]

" QUESTION: CAN THIS WORK, since there is no way to input the film speed?"

 

Perhaps you should try reading the manual.

[streetlevel]

You enter the ASA before you even go to flash mode as far as I know...so there is no need

to describe the action seperately in the flash instructions...

 

RTFM.

[steve_hovland]

If your f-stop is varying when you change the shutter speed and trigger the flash then it may mean that the meter is integrating the flash and ambient.

 

Is there any kind of indicator on the unit for percentage of flash to ambient?

 

This is actually a wonderful feature because it can help you get fine control over how your pictures look.