OK now I'm really confused!!!

gumpractitioner

gumpractitioner

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glenn
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In one of my earlier posts I bought a light meter but had problems and took it back - see thread http://www.talkphotography.co.uk/forums/showthread.php?t=186279

Now I've gone out and bought a nice new shiny Sekonic
L358. What's happening...same problem, still severely underexposing in certain situations when compared to the reflective suggestions from my canon 40D:

All images at ISO 800 f4 AWB RAW

this is 1/160 s as suggested by my Sekonic



this is 1/40 s via a reflective reading on my 40D



1/160 s by meter



1/50 s by camera


I even took several readings and averaged them with the lightmeter just in case there were difficult lighting conditions.
and yes I ensured that i inputted the correct readings in my meter as my camera, set to ambient, not stood in front of the meter, dome out and pointed at the camera. I think I have covered everything that the manual says but i am baffled. The flash readings (inside the house) seem ok and most times it gives a fairly accurate reading without flash inside the house...
any ideas?
glenn
 
No filters...I know most photographers will say why are you using a lightmeter and not your histogram and reflective meter but this meter should surely give an accurate reading and this is the point of this thread - I really need to get to the bottom of it.

thanks
glenn
 
hmmmm I'm really not sure what to suggest - I'll have a play with mine later and see how the results differ
 
EDIT: DELETED - Actually thought about what I wrote and its a load of balls.
 
I'm interested in this thread as I've been thinking of buying a light meter.
 
just to confuse things even more, I just tried metering the scene using spot metering, all the same shutter, iso settings - and the camera suggests f/9.0

Put the spot attachment on my meter and aimed at the same spot, and it also suggested f/9.0

Therefore, I would come up with the assumption, that the meter is accurately calculating the exposure for the 'subject' but not the 'scene' - if you follow me

Hence why, say you were doing a portrait, you stick your meter in front of the models face to gauge the exposure for that, rather than the whole scene. Maybe you could try your meter on something like a bottle, or a vase, something like that and check the results?

I could also be talking complete rubbish, as it is Christmas eve and I have had rather a few ales :P
 
I think it is to do with incident and reflected metering the camera uses reflective and meters an object whereas ambient meters the available light so will differ. Might be worth having a google to get a better understanding Glenn.
I think that is what is happening here.
 
Go to the sekonic website, there is a great article on both methods there. Hope it helps :)
 
Can you put up the pictures with all the EXIF data intact so we can see what your settings are? That would help in sorting the problem - otherwise it's just a guess!
 
stop using a light meter, they are not needed full stop. its better understand lighting and get a feel for it imo. plus the camera clearly does a better job here.
 
Keltic Ice Man said:
I get similar with mine. Interested to here what folks have to say.

Will do a test when i can move again ;)
Click to expand...

Dunno what you guys are doing :thinking:

Sekonic 308S, slide the invercone to one side for direct reflected light reading, ISO 400, point meter (facing away from you) at plain, evenly illuminated subject (light coloured wall in my case) so that there can be no variation or doubt in what the meter is seeing, meter reads 1/4sec at f/5.6.

Do the same with my 40D, camera says an identical 1/4sec at f/5.6. 17-55 2.8 lens at 28mm.
 
mart77 said:
stop using a light meter, they are not needed full stop. its better understand lighting and get a feel for it imo. plus the camera clearly does a better job here.
Click to expand...

To stop doing something because you cannot master it is not the way to go. Work with a meter correctly and it can be a life saver. There are situations where the camera won't get it right. Please post your images with EXIF.
 
HoppyUK said:
Dunno what you guys are doing :thinking:

Sekonic 308S, slide the invercone to one side for direct reflected light reading, ISO 400, point meter (facing away from you) at plain, evenly illuminated subject (light coloured wall in my case) so that there can be no variation or doubt in what the meter is seeing, meter reads 1/4sec at f/5.6.

Do the same with my 40D, camera says an identical 1/4sec at f/5.6. 17-55 2.8 lens at 28mm.
Click to expand...

Just did similar to give myself piece of mind, metered the wall at iso: 400 1/8th f/2.8

40D gave the same reading almost bang on.
 
so what do we think the OP is doing wrong - or does he have a duff meter?
 
I wouldnt think its the meter - I think I saw the OP post in another thread saying he had taken it back to the shop and had it tested against a 50D and the results were ok. I would think the problems are down to user error still, which is why I think some more testing would be the best plan, something like Hoppy suggested. Also like you say awp, some more images with EXIF would be good to help determine the problem
 
The only thought that occurs to me is that the OP is using it in incident mode but taking a reflective reading
 
Garry Edwards said:
The only thought that occurs to me is that the OP is using it in incident mode but taking a reflective reading
Click to expand...

That's my conclusion too.

Nothing else makes sense, even though the OP assures us he's using it correctly. Slide the invercone away, and from the camera position point the sensor at the subject (which with my Sekonic leaves you staring at the back of the meter).

How can it be different? :thinking: I would accept 1/3rd stop, even 1/2 stop difference (f/stop theory compared to T/stop actual) but no more :shrug:
 
photograph the meter.. showing the setting it suggests, with the dome pointing at the camera, and include the exif
 
Ok I'm back in the land of the living again and will try to post some shots with the exif data and will take a picture of my meter and its settings but i know that i am not taking reflective readings - i have the dome raised and pointing at the camera - in fact if i could video the whole process then that would surely put an end to the matter if its user error. (i will also try to do this)
glenn
 
Daryl said:
The light meter shots look a lot better than your in camera meter shots. I always use light meter as the Canon camera always seem to be half a stop out.

I only use histograms in the studio.
Click to expand...

Which pictures are you looking at Daryl :thinking:

gumpractitioner said:
Ok I'm back in the land of the living again and will try to post some shots with the exif data and will take a picture of my meter and its settings but i know that i am not taking reflective readings - i have the dome raised and pointing at the camera - in fact if i could video the whole process then that would surely put an end to the matter if its user error. (i will also try to do this)
glenn
Click to expand...

I just had another go, this time with an 18% grey Kodak card. Difference between the camera and Sekonic 308 is 1/10th stop less in reflective mode for the meter, as far as I can judge. It's impossible to be absolutely accurate as the camera only has 1/3rd stop increments. In incident mode, I'm getting another 1/10th stop under, as indicated. For practical purposes, these readings are all effectively identical.

For an incident reading, use the invercone and point the meter at the light source, from the subject position. For reflective readings, remove the invercone and point the meter at the subject, from the camera position.
 
In the shots you have shown us.... The highlights are burnt out in the camera measured shots, but not the hand metered ones.

You are now coming up to the time when you discover that measuring Light ( reflected or incident) is not the same as measuring exposure.

Keep it up... there is a lot to learn and it is all worth while.
 
EXIF data for above pictures (if this is any use)

1
ExposureTime : 1/160Sec
FNumber : F4.0
ExposureProgram : Manual
ISOSpeedRatings : 800
ExifVersion : 0221
DateTimeOriginal : 2009:12:24 16:01:03
DateTimeDigitized : 2009:12:24 16:01:03
ShutterSpeedValue : 1/160Sec
ApertureValue : F4.0
ExposureBiasValue : EV0.0
MaxApertureValue : F4.0
MeteringMode : CenterWeightedAverage
Flash : Not fired(Compulsory)
FocalLength : 24.00(mm)

2
ExposureTime : 1/40Sec
FNumber : F4.0
ExposureProgram : Manual
ISOSpeedRatings : 800
ExifVersion : 0221
DateTimeOriginal : 2009:12:24 16:01:20
DateTimeDigitized : 2009:12:24 16:01:20
ShutterSpeedValue : 1/40Sec
ApertureValue : F4.0
ExposureBiasValue : EV0.0
MaxApertureValue : F4.0
MeteringMode : CenterWeightedAverage
Flash : Not fired(Compulsory)
FocalLength : 24.00(mm)

3
ExposureTime : 1/125Sec
FNumber : F4.0
ExposureProgram : Manual
ISOSpeedRatings : 800
ExifVersion : 0221
DateTimeOriginal : 2009:12:24 16:00:26
DateTimeDigitized : 2009:12:24 16:00:26
ShutterSpeedValue : 1/125Sec
ApertureValue : F4.0
ExposureBiasValue : EV0.0
MaxApertureValue : F4.0
MeteringMode : CenterWeightedAverage
Flash : Not fired(Compulsory)
FocalLength : 24.00(mm)

4
ExposureTime : 1/50Sec
FNumber : F4.0
ExposureProgram : Manual
ISOSpeedRatings : 800
ExifVersion : 0221
DateTimeOriginal : 2009:12:24 16:01:28
DateTimeDigitized : 2009:12:24 16:01:28
ShutterSpeedValue : 1/50Sec
ApertureValue : F4.0
ExposureBiasValue : EV0.0
MaxApertureValue : F4.0
MeteringMode : CenterWeightedAverage
Flash : Not fired(Compulsory)
FocalLength : 24.00(mm)
 
HoppyUK said:
For an incident reading, use the invercone and point the meter at the light source, from the subject position. For reflective readings, remove the invercone and point the meter at the subject, from the camera position.
Click to expand...

In cross lit or back lit situations you need to take into account what is the main light illuminating the subject.

It may be better to point the Incident meter at the sky or majority light source.

or take a duplex reading...one pointing to the sun and one pointing from the subject to the camera, then setting an average.

This is especially helpful with wedding dresses that are side lit.
 
yes i see what you mean terrywoodenpic i may be expecting too much because i understand very little about light meters I just expecteed to get a better exposure than the ones you can see.
 
Terrywoodenpic said:
In cross lit or back lit situations you need to take into account what is the main light illuminating the subject.

It may be better to point the Incident meter at the sky or majority light source.

or take a duplex reading...one pointing to the sun and one pointing from the subject to the camera, then setting an average.

This is especially helpful with wedding dresses that are side lit.
Click to expand...
Agree!:thumbs:
 
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