[ma318]

A few quick comments.


2. A seperate spot meter is going to be much more accurate than the one built into the camera, if only because the angle of incoming light it measures is a lot less. I prefer to think of the built-in spot meter as a "region meter".

Fortunately, the accuracy can be improved with a longer focal length lens. For the istD, a 148mm focal length would make the build-in spot meter a 1 degree spot meter which could be considered an excellent spot meter. Thus using a zoom lens that can zoom out to 150mm would be advantageous when using the spot meter. Zooming out to 150mm to spot meter and then zoom back down to a short focal length for the shot.

However, a standalone spot meter would definitely be better if one is using a wide angle fixed focal length lens.


Comparison of on-camera Spot Meters

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Last edited by ma318; 02-01-2010 at 12:37 PM.

[wlachan]

I have never seen this being mentioned anywhere. Both Pentax DSLRs I have owned, DS & K-m, had the spot meter about 50% off position against the focus screen bracket. They were adjusted based on the AF sensors from what I can tell, which were also off by 50% from the factory. Fortunately, the meter sensors can be re-adjusted with minimal disassembling.

[jeffkrol]

I have never seen this being mentioned anywhere. Both Pentax DSLRs I have owned, DS & K-m, had the spot meter about 50% off position against the focus screen bracket. They were adjusted based on the AF sensors from what I can tell, which were also off by 50% from the factory. Fortunately, the meter sensors can be re-adjusted with minimal disassembling.

*-ist D is dead on AFAIKT,

[rparmar]

However, a standalone spot meter would definitely be better if one is using a wide angle fixed focal length lens.

Yes, since switching lenses just to meter is sub-optimal!

Comparison of on-camera Spot Meters

An intriguing resource. Someone with a lot of time on their hands should update it.

[adwb]

Sort of, but not really. Shots like this are not about being able to understand up front how much compensation will be needed - that's actually going to be next to impossible, because depending on exactly how you frame the shot, the meter is likely to give wildly different exposures. Shots like this are more about understanding the relationship betwene light and shaodw and figuring out how to meter such that you are not subject to those sort of random fluctuations. You may indeed need to also apply compensation, but the real trick is doing the metering in the first palce so as to give consistent results. Eg, spot metering only off the black fur, or only the white - or "substitute metering" (metering off something else that is in the same light as your subject and is has similar value ranges).

Mark , yes my thought train probably not expressed that clearly is,
1 by trying different exposures and examining the results and having found [for my eye] the best one I can then look at the histograms and get a feel for what I need to see on the histogram preview shot.
2 once I get that to that sort of fairly consistent result then that will I hope lead [ in time with practise] to being able to identify the best point to meter on to obtain that [to my eye anyway] best balanced exposure.
As far as the dog example goes I would I think have used the in camera flash turned down to -2 just to highlight the fur.
Alistair

[adwb]

Fortunately, the accuracy can be improved with a longer focal length lens. For the istD, a 148mm focal length would make the build-in spot meter a 1 degree spot meter which could be considered an excellent spot meter. Thus using a zoom lens that can zoom out to 150mm would be advantageous when using the spot meter. Zooming out to 150mm to spot meter and then zoom back down to a short focal length for the shot.

However, a standalone spot meter would definitely be better if one is using a wide angle fixed focal length lens.


Comparison of on-camera Spot Meters

Yes a hand held spot meter would be nice but have you seen the prices? even on Ebay very expensive.
For me the zoom option will have to suffice for now.
Alistair

[adwb]

I have never seen this being mentioned anywhere. Both Pentax DSLRs I have owned, DS & K-m, had the spot meter about 50% off position against the focus screen bracket. They were adjusted based on the AF sensors from what I can tell, which were also off by 50% from the factory. Fortunately, the meter sensors can be re-adjusted with minimal disassembling.

Alan how can you tell if the meter is off centre?
Alistair

[wlachan]

Alan how can you tell if the meter is off centre?
Alistair

Read the 3rd paragraph.

Spot Meter Re-alignment Photo Gallery by Alan Chan at pbase.com

[jeffkrol]

Alan how can you tell if the meter is off centre?
Alistair

It is fairly easy to judge the relatively precise position by just setting the camera to spot meter and meter a white or monotone wall w/ something like a dark plate on it. Slowly move the camera up/down and left/right watching the meter change the f stop/ speed...

[systemA]

My k20d has a spot metering point that is a bit lower than the middle of the screen. Paint a black dot in PS and slowly move from the center outwards in every direction, noting the change in shutter speed (in Av mode). You will have outlined your metering point.