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01-17-2009, 11:29 AM   #1
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Metering Help (K100D + M lens)

Hi everybody,

I've just had an epiphany!

I was writing this to ask how the heck to meter with a "M" lens. It did not seem to be working for me the way I thought it should work!

I've just now discovered it.

So for any dunce's like me in the future, yes you put the camera in "M" mode and press the AE-L button like everybody says, but NO the "*" won't come on, but the camera does set an appropriate shutter speed.


This has, however, lead me to a new question...I'm going to go out on a limb and assume that the camera is metering to ±0, and then if I want to shift up from that, I need to then click the shutter speed down a little every time I press AE-L...right?

Thanks,

01-17-2009, 12:11 PM   #2
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Well, my experience has been, that with my K110D ( the same as K100D minus shake reduction ) is that exposure is pretty accurate with M lenses using the AE/L button, my K10D on the other hand, isn't so good ( unless I only use F4 )

And yes, if you want to adjust exposure up or down, you can click 1 up or down on shutter speed to compensate. But with my K110D, I haven't really had the need to compensate.

Here are a few shots with my K110D and an RMC Tokina 28mm all manual lens. All using the AE/L button in M mode, no compensation.






Last edited by Stratman; 01-17-2009 at 12:19 PM.
01-17-2009, 12:14 PM   #3
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On some cameras (I can't speak for the K100D) the Ev compensation works in manual mode as well as well as P etc.). Try an experiment - meter with the Ev at +/-0 and note the result, then do the same at Ev +2 and see if you get a two stop different shutter speed.

If Ev compensation doesn't work then you'll have to either adjust the aperture or the shutter speed before shooting to compensate.

BTW, you have set the appropriate custom function to "Using Aperture Ring", right?
01-17-2009, 12:21 PM   #4
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QuoteOriginally posted by Saaby Quote
I was writing this to ask how the heck to meter with a "M" lens. It did not seem to be working for me the way I thought it should work!

I've just now discovered it.

So for any dunce's like me in the future, yes you put the camera in "M" mode and press the AE-L button like everybody says, but NO the "*" won't come on, but the camera does set an appropriate shutter speed.

According to page 188 in the manual (pdf Download) there are more ways than "M"anual, Av is available too - yeah, I know, as the Last resort - read the ******* manual!



01-17-2009, 01:33 PM   #5
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Few notes:
-In A mode many M42 lenses meter incorrectly on my k100d, unless the A/* pin is shorted, compared to M Mode + AE-L, iwch tends to meter more correctly without the pin shorted.
-To add a compensation, be aware thant one dial clock for shutter speed, isnt one stop.
For example, if tou meter 1/1000s, one click would result in something like 1/800, but one EV stop is half the light, so you have to dial 1/500, wich requires several stops.
I belive the same aplies to aperture, although i havnt tested.
01-18-2009, 12:24 AM   #6
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Okidoke, a little experimentation and here's what we get...

Shooting in M mode:

± -- there's no way to shift the metering since you're in full manual mode. Pressing the ± button does nothing. Changing the value in another mode and then switching to "M" mode, unsurprisingly, has no effect on exposure.

Shooting in any other mode:

The camera will say "Av" on the display, but it's not Av at all -- unless you have your lens set wide open. In all the other modes you /can/ shift Program-AE with ±, but the lens shoots only wide open.

Shooting with flash:

The flash only fires full force, I think this is commonly known. Pressing AE-L does not compensate for the flash that will be on. Just keep the flash down and everything will run smooth. You bought a f1.7 lens so you wouldn't have to use flash anyway, right?


So I would say this is the definitive guide to shooting with "M" lenses, in 100 words or less.

With an "M" lens and the camera setup appropriately, you have your choice of 4 shooting modes.

Av (For smallest f-stop only) with program-shift. -- Set the dial to anything besides "M" or "B" and shoot as normal. The only way for you to adjust exposure is with the ± button.

Av for your choice of Aperture -- Set camera to "M." Pick aperture using lens ring. Half-press shutter button to activate metering.* Press AE-L button to stop-down lens and meter. Press shutter release to take photo. If you're unhappy with the camera's exposure, you can "program shift" by adjusting the shutter speed after you meter.

*It may be helpful to set your metering to stay on 30 seconds rather than the default 10. DO this in the "C" menu.

Full manual -- Put camera in "M" mode, set aperture on aperture ring, set shutter speed with wheel. Good luck!

Bulb -- Bulb also stops down the lens as you'd expect it to.
01-18-2009, 02:57 AM   #7
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QuoteOriginally posted by Saaby Quote
± -- there's no way to shift the metering since you're in full manual mode. Pressing the ± button does nothing.
If you press the ± button and simultaneously use the dial, it will change the aperture but only if the lens supports this, i.e., not with an M lens.
QuoteOriginally posted by Saaby Quote
The camera will say "Av" on the display, but it's not Av at all -- unless you have your lens set wide open.
You should also be able to use exposure compensation to correct for other apertures than wide open.

01-18-2009, 07:52 AM   #8
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QuoteOriginally posted by Class A Quote
You should also be able to use exposure compensation to correct for other apertures than wide open.
AFAIK, the only way is to shift the shutter speed in "M" mode which, as noted here, isn't 1 click = 1/3 a step or anything along those lines.

However when you do it the camera does show your exposure, so it's not all that much of a problem or challenge to adjust.

It's not that difficult, just a matter of getting to know your gear. If, however, there's an easier way to shift exposure with a "M" lens, and apertures other than wide open, I'd be thrilled to know how. The more you know the better, right?
01-18-2009, 09:53 AM   #9
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QuoteOriginally posted by Saaby Quote
AFAIK, the only way is to shift the shutter speed in "M" mode which, as noted here, isn't 1 click = 1/3 a step or anything along those lines.
??? sure it is. It's either 1/3 stop for click or 1/2 stop stop per click, depending on which way you set it up in your custom options.
01-18-2009, 01:43 PM   #10
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Well there you go. ß
01-19-2009, 04:21 AM   #11
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QuoteOriginally posted by Saaby Quote
However when you do it the camera does show your exposure, so it's not all that much of a problem or challenge to adjust.
If the lighting is static, there's not much of a difference. If it changes while you are trying to capture a moment, Av mode can be helpful.

EDIT: My previous hint to use Av + exposure compensation doesn't work with M lenses. Sorry. I took someone else's word for granted without trying it myself. In Av, the lens indeed always stays wide open (unfortunately, no good reason that it is that way, AFAIK).

Last edited by Class A; 02-05-2009 at 04:49 PM.
01-19-2009, 09:33 AM   #12
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QuoteOriginally posted by Class A Quote
If the lighting is static, there's not much of a difference. If it changes while you are trying to capture a moment, Av mode can be helpful.


Just put the camera into Av and use exposure compensation to make up for the fact that you aren't shooting wide open.

But the whole point is that if you use an M lens in anything other than M (manual) exposure mode, the camera will take the picture wide open irrespective of where you set the aperture. Using Av mode is of no use UNLESS you purposely intend to shoot wide open.
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