Spot metering

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piero2025

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I am quite new to rangefinders, coming from reflexes.
When taking a backlit portrait, I would switch to spot metering, point the center of the finder on one cheek and adjust the value for skin type.

Can I simulate that on my RF (Zeiss Ikon ZM)?
 
If you come close and point rf patch where you want to meter it should work. Never owned ZM, but should be not different from L/T/R line, where metering was closer to the spot metering.
Or point the RF patch to the light source for the cheek to measure it.
 
The ZM does not have spot metering. What you can do is get up close to your subject (as close as you can, where the meter reading is not picking up the light behind the subject) and take a reading. Use that reading for your exposure.
 
There are techniques for metering off your hand but this get tricky depending on all the variables.
 
Any Leica (including the SLR) with a built in meter have a seriously center weighted meter. More so than the Nikon SLR meters with the 60% center weighted meters. On your ZM RF, a little trial and error is needed, but just open up 1 or 1 1/2 stops over what the camera meter is telling you.
 
Beemermark said:
Any Leica (including the SLR) with a built in meter have a seriously center weighted meter. More so than the Nikon SLR meters with the 60% center weighted meters. On your ZM RF, a little trial and error is needed, but just open up 1 or 1 1/2 stops over what the camera meter is telling you.
Click to expand...

My rule of thumb is to open up by 1½ stops, a technique I copied shamelessly from the little switch underneath the Olympus XA. The other technique for P&S's is to use fill in flash and one or two P&S's even look at the exposure over the entire frame and expose for what they "think" is important, ie the centre of the frame. I spent years learning to meter the hard way and then got upstaged by a P&S...

BTW, the serious Leicas' metering isn't centre weighted, it's centre only or a large spot; call it what you like.

Regards, David
 
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Beemermark said:
Any Leica (including the SLR) with a built in meter have a seriously center weighted meter. More so than the Nikon SLR meters with the 60% center weighted meters. On your ZM RF, a little trial and error is needed, but just open up 1 or 1 1/2 stops over what the camera meter is telling you.
Click to expand...

This doesn't sound right to me. Opening 1 1/2 stops would get you the right exposure if the area you happened to have metered was reflecting 1 1/2 stops more light than the average value of the scene. On the other hand, if it was reflecting 18% of the light striking it, and you open up 1 1/2 stops from there, then you'll be overexposing by 1 1/2 stops.

The way I use a spot or limited-area meter such as the M5's is to meter off an area I'm sure is representative of the average value of a scene. Some favorites are green grass; a faded asphalt road surface; the blue sky 90 degrees away from the sun and fairly high, not near the horizon. Or anything else that is a reasonable approximation of 18% reflectance. Sometimes I bring an 18% gray card, but usually I don't. An incident meter eliminates all guesswork, and can often be the best way.!
 
I don't think this method can work without an actual spot meter. A wider angle reflected meter held close by will not be reliable to read an area as small as a part of a human face. But a portrait where you have time for spot metering sounds like you could also use an incident meter.
 
On my ZM, I frame up the shot, pan the camera to point at something dark in the frame (close to the value I want expose for. I’ll watch the LED shutter speed indicators in the finder for reference), hit the AE lock button, focus, re-compose, take the picture.
 
willie_901 said:
Zeiss' ZM manual states "TTL, center-weighted metering". The only other metering information in the manual is the meter f-stop ranges.

I don't know the details about weighting percentage, etc. Perhaps some of the ZM body reviews from 2006 discuss the metering inn more detail?
Click to expand...

This is one of the oddities that plague us; they never give you all the information about the metering and you are left wondering. Sometimes you get what's missing from the instructions in the sales brochure and vice versa. (A good reason to collect brochures, btw.)

The fact that the Leicas I use are centre only and not centre weighted is great but few seem to notice or comment on it.

Anyway, the answer with overall metering seems to be add 1½ stops and - perhaps - the answer to CW is a bit of experimentation starting at (say) +½ ? The answer seems to be trial and error for each camera system.

Regards, David

PS This raises a point that puzzles me; with digital cameras why doesn't the "Landscape" setting switch the metering to ignore - almost - the sky?
 
David Hughes said:
PS This raises a point that puzzles me; with digital cameras why doesn't the "Landscape" setting switch the metering to ignore - almost - the sky?
Click to expand...

I owned Nikon DLSRs that offered modes like this. The D700 matrix metering mode would choose a sensor-exposure spatial distribution pattern based on a set model scenes. These model scenes were created using huge number of digital images. The sensor metering regions would be weighted in real time based on one of the scenes. I think of this as a primitive artificial intelligence system. The meter weighting would be very different for a landscape composition that was 30% sky and a landscape composition that was 10% sky. I found this to work very well and quickly.

No doubt other brands offered similar functionality. All I know is the D700 matrix metering mode was completely reliable.

As you mentioned, the problem is all these real-time, meter-weighting algorithms are proprietary. Details about how these real-time meter weighting algorithms work are scarce. Initially, it is difficult to trust highly automated exposures.
 
willie_901 said:
Zeiss' ZM manual states "TTL, center-weighted metering". The only other metering information in the manual is the meter f-stop ranges.

I don't know the details about weighting percentage, etc. Perhaps some of the ZM body reviews from 2006 discuss the metering inn more detail?
Click to expand...

With the ZM. as with many cameras, one can get some insight into the areas of the frame that are more heavily weighted by looking at the shutter itself. There will be a gray or white area from which the meter will (predominantly) read the light.
I've always wished that cameras would offer either true (non-weighted) averaging, or spot metering, or ideally both. I'm always annoyed by the uncertainty and vagueness of center weighted meters. I pretty much rely on a hand meter when shooting with a camera that only offers that option.
 
I have found the center weighted meter on the Ikon to be extremely accurate and friendly to use. It seems like it's probably a riff on the meter from the Nikon FM-10 (so probably 60/40).

When shooting in backlit situations, just point the camera at something dark in the scene (preferably slightly darker than your subject to account for any light spillage tricking the meter), use the AE lock, re-compose and shoot (the AE lock button is really nice).

Examples:

Jenny by Jim Fischer, on Flickr

I pointed the camera down, at the subject's gray dress to set the exposure.

Jenny by Jim Fischer, on Flickr

I pointed the camera waaay down, locking exposure on the red couch (to try to exclude as much light as possible coming in from the windows).

Patti & Steve by Jim Fischer, on Flickr

Locked exposure on the tablecloth.

Basically, if it's negative film, err on the side of over-exposure and you'll be fine.
 
While the ZM manual doesn't address this situation other camera manuals do. The Olympus OM-1 manual states "one full stop over the meter reading. If there is a lot of bright, sunny sky behind the subject and there no light being reflected on the subject's face then I open up 1 1 1/2 stops. Same as taking a picture of a subject in deep shadow using the sunny 16 rule.
 
Beemermark said:
While the ZM manual doesn't address this situation other camera manuals do. The Olympus OM-1 manual states "one full stop over the meter reading. If there is a lot of bright, sunny sky behind the subject and there no light being reflected on the subject's face then I open up 1 1 1/2 stops. Same as taking a picture of a subject in deep shadow using the sunny 16 rule.
Click to expand...

That may often work as a rule of thumb, but not always. Backlighting comes in varying intensities without any rule to govern them all. Metering (the actual light at or light equivalent to that at) the subject is the only way to be sure.
 
willie_901 said:
I owned Nikon DLSRs that offered modes like this. The D700 matrix metering mode would choose a sensor-exposure spatial distribution pattern based on a set model scenes. These model scenes were created using huge number of digital images. The sensor metering regions would be weighted in real time based on one of the scenes. I think of this as a primitive artificial intelligence system. The meter weighting would be very different for a landscape composition that was 30% sky and a landscape composition that was 10% sky. I found this to work very well and quickly.

No doubt other brands offered similar functionality. All I know is the D700 matrix metering mode was completely reliable.

As you mentioned, the problem is all these real-time, meter-weighting algorithms are proprietary. Details about how these real-time meter weighting algorithms work are scarce. Initially, it is difficult to trust highly automated exposures.
Click to expand...

Thanks, I've often wondered about this and have long suspected that one or two P&S's have it. I figure that face detection is commonplace and, probably, complex and so blue sky with fluffy white clouds out to be simple but they don't do it. Why face detection is needed when we've all be able to do it from a week or so after birth escapes me but I guess it sells cameras.

Regards, David
 
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