Sekonic L-358 Reading Compensation?

Discussion in 'Lighting' started by floatingchildsface, Feb 9, 2012.

  1. floatingchildsface

    floatingchildsface Member

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    Hi I just got a Sekonic L-358 (my first handheld meter) and will be shooting with my Mamiya 7/80mm, probably Ektar 100, and Fuji 400H, and maybe some slide film as well.

    I am wondering, if the meter is accurately calibrated, should I be compensating the readings at all? Or should I set my EV to what is read on the L-358?

    Reason I ask is I just read some things online about the Sekonics (and other meters) being calibrated for 12.5% grey, whereas a grey card is 18%... Has me a bit confused.

    I understand that there are creative decisions involved in setting the EV but as a baseline, I want to make sure I am starting off correctly.

    I will be shooting a variety of outdoor scenes.
     
  2. CGW

    CGW Member

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    Do you have any reason to think your meter is "off?"

    If not, then don't get into a frothing OCD fit over the slim possibility your meter needs calibration. Though I believe you can dial in a fixed adjustment(I can on my 558), I'd make sure it's "zero-ed" with no +/- and leave it be.

    I have 3 Sekonics and none have ever disappointed in the accuracy dept. I'd put aside the chatter about baked-in inaccuracy and what the "real" gray card % is and make up your own mind. If you're shooting C-41 film, the material's latitude, especially for over-exposure, will absorb any slight metering/exposure anomalies. E6 is less forgiving but here, too, post-exposure processing can even things up.

    Just make sure you know how to take an incident reading. Bad technique can screw things up and might be a bigger worry than possible calibration issues with your meter.
     
  3. stavrosk

    stavrosk Member

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    I use me Seconic for incident metering whoch I dont think can be calibrated for gray card.
    I use the exact values it tells me and my exposures are spot on.
     
  4. Matthew Wagg

    Matthew Wagg Member

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    I do have a problem with my 358 with ambient metering. So i'd be interested in seeing if there is a resolution to this.
    In the other modes its as accurate as accurate but in ambient mode its way out. The app in my android phone is more accurate than the sekonic.
     
  5. CGW

    CGW Member

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    Accurate in what other modes? Flash? Reflected? "Way out" by how much?
     
  6. Chan Tran

    Chan Tran Member

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    Sekonic and Minolta have different calibration standard but the difference is only about 1/6 stop. Besides that it's difficult to tell if the meter is accurate unless you have a known good meter to compare with or the meter is way off that you can tell by compare with sunny 16 rule or something like that.
     
  7. Matthew Wagg

    Matthew Wagg Member

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    The corded flash and auto reset flash modes are accurate. I only meter in incident mode as I am mostly a portrait photographer.

    It is in the ambient mode that it is out. Both in shutter priority and apeture priority modes. I just stepped outside and took an incident reading at iso 400 @f4. The Sekonic reads 1/160. My phone's meter read 1/125 which is what my dslr read the scene at as well. It doesn't just over expose though, it can and has underexposed a scene by 3 stops before when I relied on it to meter with my C330. I pretty much just got a roll of blackness back from then.
     
  8. CGW

    CGW Member

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    Just to be sure: ambient=incident. You're using the dome fully extended? Your dslr is giving a reflected light reading and it will vary from a 358 incident reading. Just make sure via the manual that there's no calibration or exposure adjustment dialed in. BTW, how do you take an incident reading?
     
  9. Matthew Wagg

    Matthew Wagg Member

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    Yes the dome is extended. I only use the dome retracted if I'm taking pictures of other pictures or paintings. When I'm metering I use a similar method to the Kirk Tuck and Vincent Laforet does when they're working. There are videos of them on the Sekonic site.

    I know the dslr is giving reflected but my phone's lightmeter agrees with the dslr and the histogram reading matches what I'd expect to see from the reading. But that's the digital side of things and we shouldn't talk of such things in here :wink:

    When I meter, for example in an indoor portrait session I will take mulitple readings from the top, front, sides and rear (usually around six seperate meter readings to check the light falloff is right and set my camera for the highlights. I like to know how much falloff I have around my models to control my light better.

    Doing the same thing in an outdoor session in the ambient metering mode on the 358 I get erratic readings similar to the ones I posted above.
    Say I'm using my OM2 and you have the +- symbols light up (reflected). When using my phone light meter they match up nicely when I set the OM2 to the settings on my phone. However on the Sekonic it will either register above or below (over and under exposing). That's ok when I have a relfected meter to fall back on in camera to ballpark my figures but with my C330 that doesn't have any metering I have to rely on external metering.

    I am thinking actually after explaining this, that I do have a problem with my sekonic. Thanks. I hope that this info is useful to someone else and I haven't just hijacked the Op's thread for nothing. Sorry about that by the way.
     
  10. Chan Tran

    Chan Tran Member

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    the reading that you posted is only a third stop difference from your DSLR and it's a reflective vs incident as well isn't much of a difference. Now a third stop is a big difference if the readings are compared with the same type and of the same meter pattern, angle of view etc.. but for 2 different types of reading it's kinda unknown.
     
  11. CGW

    CGW Member

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    Aside from the off chance your 358 is sick, I'd still go back into its settings menus and check for any dialed in compensation and zero it. I'm not getting the point of your incident metering technique in either setting. Ratios??? Have you simply taken a single outdoor incident reading with the dome pointed at the camera, at, say, ISO 200, dialed in the setting manually on your dslr and checked the results?
     
  12. Chan Tran

    Chan Tran Member

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    I think there is adjustment to bias the reading to what you like but it would effect flash reading as well.
     
  13. benjiboy

    benjiboy Subscriber

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    Don't believe all you read, the Sekonic Grey Card is 18% Grey and that's what the meters are calibrated for http://www.warehouseexpress.com/buy-sekonic-grey-card/p1009297
     
  14. John Koehrer

    John Koehrer Subscriber

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    I've read online that in use IF you read the Kodak instructions, you don't hold the card straight up but at an angle and when held at that angle it's actually 12.5%.

    I believe this was from a writer of columns for one mag or another.
     
  15. Poisson Du Jour

    Poisson Du Jour Member

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    The meter can be calibrated to take into account filters e.g. +1.6 (varies for each filter). Baseline calibration is with ISO 1 and ISO 2 buttons pressed simultaneously.

    The meter does not require any additional calibration on the premise of making sure the exposure is correct — that is your responsibility, gained through active experience using the meter.

    I would ignore most online commentary regarding the Sekonic baseline mid-tone calibration: it is not particularly well-informed.
     
  16. Leigh B

    Leigh B Member

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    If you just got the meter, why do you suspect that it's off???

    I had a 358 for several years, then replaced it with a 558 to get the spot capability.
    I found both of them to be right on. Sekonic meters are accurately calibrated at the factory.

    Proper exposure has a lot to do with your shooting and processing habits.
    If the meter doesn't produce what you want after a lot of experimentation, then adjust it.

    - Leigh
     
  17. Helinophoto

    Helinophoto Member

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    I use one, both in the studio and outside.

    Never had any problems.

    Remember that what your camera meters and what your meter is reading, can differ greatly, depending on what metering mode you have set your camera to, the meter doesn't have spot readings either, not matrix, not center weighted etc.

    I don't know....I just trust it, but I make sure to meter correctly and several times to avoid any misreadings/errors on my part when I am outside.
     
  18. Bill Burk

    Bill Burk Subscriber

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    Unless you carry and take readings off 18% gray cards, the issue with 18% is irrelevant.

    ---

    Your meter has a built-in gray reference (the white dome), and your meter is calibrated to its own dome. As long as the meter is not out of whack, you should be able to use it with factory settings.

    I enjoy discussing the different factors, but the bottom line of what I have learned is that the important factors are there for a reason and they are built into the calibration standards.

    My simplest advice: Set the EI in your meter at the rated or actual speed of your film, and then change the EI if you find out you have to.

    If you change the way you meter, like if you decide to start doing BTZS (Beyond the Zone System) metering techniques, then you might have to change your EI again.

    Traditional Zone System spot metering with traditional N development often results in EI approximately half the rated speed. That's what I do and is why my EI is 2/3 stop "lower" than the actual speed of the film.
     
  19. Bill Burk

    Bill Burk Subscriber

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    I have one of those, and it has a series of patches centered on 18%. (So nominally the card is 18%). But I believe the way you use it attempts to "place" the exposure on 18%. You meter with incident light and shoot the card with a camera. Then you analyze the results.

    You'll be pleased to know that the incident light reading does NOT agree with a spotmeter reading off 18%. It agrees more closely with a spotmetering off the 12.7% patch!
     
    Last edited by a moderator: Feb 9, 2012
  20. markbarendt

    markbarendt Subscriber

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    I have 2 of the 358s and they are highly reliable.

    No other piece of equipment I own adds more to any shot.

    I can hardly imagine it providing you a problem.