Pentax Digital Spotmeter

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konastab01

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So I understand photography and ive got a pentax digital spot meter but for the life of me im not 100% sure if im using it right and YouTube isn't really bring up information on how to us fit proper.

The way i'm understanding it you set the ISO first, you then change the aputure and it says a number which im guessing is then your settings but surely the shutter speed isn't fixed always.

I feel a bit daft with this.
 
konastab01 said:
The way i'm understanding it you set the ISO first, you then change the aputure and it says a number which im guessing is then your settings but surely the shutter speed isn't fixed always.
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The number displayed in the viewfinder is an EV number (see here: https://photographylife.com/exposure-value )

You set that on the dial at the back of the lens, which locks all the possible combinations of aperture and shutter for that exposure. Read the link above which will tell you more than you probably want to know. Basically, EVs give you an absolute light value. They were the hot property in photographic technology in the 1950s and 60s but are actually quite simple to understand and use.
 
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I just downloaded the manual and skimmed to the part on using it. From wht I hastily read, it seems that the number displayed is the EV (exposure value), a system designed to make it easy to adjust settings on compatible cameras. Be that as it may, I'd guess that there are two rings you can turn on the thing with the scales. Turn the front one to set the film speed, then turn the one behind to line up the EV value in the viewfinder with the index mark. You then have a set of shutter speeds and apertures to choose from.

The tricky part with any spot meter is knowing what to meter, and how to use the information, as unlike non spot meters it won't normally give you a value you can just use.

Andrew's post was made while I was typing...
 
AndrewFlannigan said:
The number displayed in the viewfinder is an EV number (see here: https://photographylife.com/exposure-value )

You set that on the dial at the back of the lens whch locks all the possible combinations of aperture and shutter for that exposure. Read the link above which should make it clear. EVs were the hot property in photographic technology in the 1950s and 60s and actually quite simple.
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Thanks andrew, I understand the principles so thought it must be pretty simple. Ill give that a read!
 
StephenM said:
I just downloaded the manual and skimmed to the part on using it. From wht I hastily read, it seems that the number displayed is the EV (exposure value), a system designed to make it easy to adjust settings on compatible cameras. Be that as it may, I'd guess that there are two rings you can turn on the thing with the scales. Turn the front one to set the film speed, then turn the one behind to line up the EV value in the viewfinder with the index mark. You then have a set of shutter speeds and apertures to choose from.

The tricky part with any spot meter is knowing what to meter, and how to use the information, as unlike non spot meters it won't normally give you a value you can just use.

Andrew's post was made while I was typing...
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Yeah that's the thing, using digital DSLR most of my life ive always thought that they spot metered.
 
konastab01 said:
Yeah that's the thing, using digital DSLR most of my life ive always thought that they spot metered.
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They usually have multiple options, including some sort of matrix/center weighted & spot.
I think the normal DSLR spot is typically wider than a standalone spot meter though of course it will vary with the lens fitted. With a 1000mm lens thew DSLR is likely to be considerably narrower.
 
Assuming that a spot meter measures light ONLY from the indicated spot in the viewfinder, what it will tell you is what settings to use to render the selected spot a mid grey (it's easier to talk in black and white terms :) ). If the area you selected isn't a mid grey, the reading won't give you the results you expect, because the exposure will make that spot mid grey. The benefit of a spot meter comes from measuring the darkest area you want detail in, and the brightest area you want detail in. With luck and a fair wind, the difference between the values will fit the film's ability to hold detail. If not, you either choose what to sacrifice, or, if a black and white film, adjust the development time to make it fit.

Many people swear by spot meters, and many swear at them... I used to use a Sekonic spot meter. 'Nuff said.

On the first part of my reply, I did actually test the effect of out of spot areas on the reading given. Trust me, the discrepancy was of a size that more than cancels out any extra accuracy of spot metering over an incident method - which is why I meter the palm of my hand and open up one stop. I posted the figures here a long time ago.
 
StephenM said:
Assuming that a spot meter measures light ONLY from the indicated spot in the viewfinder, what it will tell you is what settings to use to render the selected spot a mid grey
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I've never been a fan of spot metering - a Weston with an Invercone was always more suited to my needs.

However I did know a bloke who worked for one of the big ship chandlers in the 1960s. He often had to take pictures of ships from the shore and in the absence of through the lens metering, a spot meter got his Kodachromes "spot on". ;)
 
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Petrochemist said:
They usually have multiple options, including some sort of matrix/center weighted & spot.
I think the normal DSLR spot is typically wider than a standalone spot meter though of course it will vary with the lens fitted. With a 1000mm lens thew DSLR is likely to be considerably narrower.
Click to expand...
Yeah ive always had mine set at spot. So that's why I felt that the spot was the most uselful.
 
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