Sekonic M8 profile

[ammitsboel]

I looked at the Sekonic lightmeters and chose the L-758D.
Has anyone in here tried profiling their M8 for this meter?

I'm curious as to what the advantage is by doing this?
Can the exposure settings deviate a lot from a standard ISO rating taken off the meter?
My intention is to take one reading at a location(like a wedding), and then use that setting until the light changes.

It seems I'm all about questions these days...

/Henrik

[giordano]

Originally Posted by ammitsboel

I looked at the Sekonic lightmeters and chose the L-758D.
Has anyone in here tried profiling their M8 for this meter?

I'm curious as to what the advantage is by doing this?
Can the exposure settings deviate a lot from a standard ISO rating taken off the meter?
My intention is to take one reading at a location(like a wedding), and then use that setting until the light changes.

Profiling seems to involve calibrating the meter (I don't own this one) to the characteristics of the camera. The Sekonic blurb suggests that variables in the sensor and elsewhere can amount to half a stop or so in either direction (which seems reasonable to me) and claims that the meter is accurate to 1/10 stop.

So if profiling works, it would reduce an error - between the exposure suggested by the meter and the one that should be set on the camera - of up to half a stop to at best 1/10 stops. That could be quite useful in scientific and photogrammetric applications or anywhere very precise exposures are required and bracketing is impossible or undesirable.

I don't do weddings, but somehow I doubt whether profiling the meter would have any practical benefit except perhaps for the posed shots.

[ammitsboel]

Thanks John, my worries is that I might spent my time better doing other things than this calibration, but maybe I'll do it anyway.

[Kent10D]

I have the meter, and even purchased the calibration target, but since the meter works so well as is I simply haven't bothered. Maybe one day.

I'm sure that helped a lot.

[wstotler]

Originally Posted by ammitsboel

Thanks John, my worries is that I might spent my time better doing other things than this calibration, but maybe I'll do it anyway.

Post is a little long, but let me throw out some thoughts for you.

The meter you just bought is so good that calibration is probably less important than getting your head around using it!

It will tell you one thing that your M8 can't ever tell you: What's my incident light reading? (In EVs.)

You're be better served to just use Sekonic "stock" and really get good at learning how to take incident light EV readings and setting the M8 per its readings.

I have the Gossen DigiSix, which does a credible job for being such a small tool.

Few words on incident light metering

People / Things
----------
Meter held just in front of the subject's head. Or held to the side of the head, a half an arm's length straight out from the ear. White dome faces the light--like the subject's face faces the light. (Stay out of the light when you meter, BTW.) E.g., Light falling on dome replicates light falling on subject's face. (The dome becomes a "little face" figuring out the average of light falling on it.)


General Environment
----------
White half-dome shape facing up, toward the sky. Light falling on dome replicates light falling on the scene. (This varies depending on conditions, but its a good starting point.)


In both cases, the incident meter tells the "truth" about what the average light is.

99% of my shots give me good results if I just trust the meter--I get good, "average" lighting from the scene that I can darken/lighten in post.


Tricks: With time, you'll learn to "grab" light readings by varying positioning based on these two basic scenarios. Holding the meter differently will give you different final effects. Just have to play with it to try that out.

Also note that I've found that working with incident light metering/setting the M8 produces a whole different look coming out of the camera. It's not "right" per se, but it is a different look. (From the spot metering.)

There's a thought that you can learn enough about how light works that you can judge, in your head, "my spot meter says X my incident light should be about Y so I should compensate by Z on the M8." Good luck with that. I've gotten pretty good at judging interior, indoor lighting at night to get what I want. Other scenarios, for me at least, are more complicated.

In other words, I trust the M8's metering to take photos that look a certain way. I trust my DigiSix to let me meter out a scene's incident light to take photos that look a different way.

I know I get a higher ratio of "keepers" having set the M8 according to incident light and just shooting.

Later--and have a blast with your Sekonic!
Will

P.S. When I got the DigiSix I carried it around in and sampled just about everything all day long for about two weeks. (This was after reading five different books about exposure.) It was amazing to view the world in EV incident light readings. It let me ask the questions: What kind of light do I *want* to have for the kind of photos I *like*. And where/when can I find that light? (And led me months later into making the kind of light I wanted with a light kit.) It was like successful prospecting--fun and rewarding.

[stunsworth]

I always though the way to use an incident meter was to take a reading from the position of the subject with the white dome pointing at the camera rather than the light source?

[Samir Jahjah]

Originally Posted by ammitsboel

I looked at the Sekonic lightmeters and chose the L-758D.
Has anyone in here tried profiling their M8 for this meter?

I'm curious as to what the advantage is by doing this?
Can the exposure settings deviate a lot from a standard ISO rating taken off the meter?
My intention is to take one reading at a location(like a wedding), and then use that setting until the light changes.

It seems I'm all about questions these days...

/Henrik

My understanding (I think Sean mentioned this at some point) is that the ISO setting on the M8 is on the conservative side. Sean recommends to set your lightmeter at 200, 400, 800, 1600, 3200, when you select 160, 320, 640, 1280, and 2400 respectively on your M8.

[dfarkas]

Originally Posted by stunsworth

I always though the way to use an incident meter was to take a reading from the position of the subject with the white dome pointing at the camera rather than the light source?

Steve,

An incident light meter is designed to do just that: measure light. If you have a front-lit subject, metering toward the lens will be fine, but if you have a back-lit or side-lit subject your results will vary greatly depending on what you are metereing.

For back-lit subjects, metering toward the camera will give you a "properly exposed" subject, but will be totally blown-out in the background. If you meter the light (behind the subject) you will get a "perfectly exposed" background and a sillhouetted subject. This is why fill-flash was developed, which matches the rear lighting in the front with strobe.

For side-lit subjects, if you meter in the middle of the face, under the chin (so the dome is half-illuminated) you will get the highlight side overexposed by about 1 stop. If you meter the shadow side, you will overexpose the highlight side by about 3 stops. But, if you meter the light striking the subject toward the light source (the sun, in this case) you will get the right exposure. The shadow side will be dark, but nothing will be blown out.

When you introduce strobe lighting, you want to set your exposure to the meter reading of your main light. This is the same concept as the side-lit ambient example. In studio, or using battery-operated power packs on location, each light source does need to be metered independently. There is no way to guesstimate here. The more lights you add, the more careful you must be with metering. As they say, "meter twice, shoot once"

So, basically, no hard and fast rule with metering. It is a tool that needs practivce and mastering, just like any other.

BTW, the L-758DR is an excellent meter. I have an L-558R (the immediate predecessor), an L-358, an L-308S, as well as a Gossen DigiFlash. I guess meters are like tripods and camera bags.... you can never have too many.

David

[wstotler]

Originally Posted by stunsworth

I always though the way to use an incident meter was to take a reading from the position of the subject with the white dome pointing at the camera rather than the light source?

Yes. I'm presuming that the light is falling on the front of the subject from a light source behind the camera--and that the camera is in front of the subject. The "point the white dome at the camera lens" is assumed.

So, yes, point the white dome at the lens of the camera--not at the light--as a starting point. (For subjects.) What I said about getting a "general scene" light reading--white dome facing up--still applies.

Sometimes I will meter the light falling on the subject with the white dome facing in the general direction of the light source (not the camera's lens), when the light is falling on the side of the subject (and not on the front, assuming I'm shooting the front with that side-lighting condition). You can lose subject detail in the shadows--I've found they're normally recoverable in RAW--but you'll never totally blow out.

Thanks,
Will

[giordano]

Originally Posted by stunsworth

I always though the way to use an incident meter was to take a reading from the position of the subject with the white dome pointing at the camera rather than the light source?

With a small hemispherical receptor as on Gossens and Sekonics, this works most of the time. If there is strong side or back-lighting, you may do better to take one reading pointing at the camera, another pointing at the main light source, and use the average of the two. That technique is essential if you're using a flat receptor.

With a Weston Master/Euromaster, the large late-model Invercone was designed to take account of light coming from just about everywhere but directly behind the meter, giving a degree of automatic compensation for side and back-lighting (so long as you hold the meter in the full light).

But what matters most is what works for each user.

[Jamie Roberts]

The nice thing about calibrating your camera (or your film, for that matter) to your meter is that you can do things like know when you're getting blown highlights or enough shadow detail. Not necessary for general exposure, but it's in the fine points and I'm glad the newer electronic meters are making this easier to do than before.

As for the incident dome, position and side-lighting, in my experience I haven't had any trouble with overexposure (or underexposure) on side-lit subjects with film or digital, and as long as I'm using the incident dome on my Gossens and Seikonics I point it towards the camera lens (sidelighting and such is what the dome is supposed to take into account).

For doing copy work, and not using the dome, then I'd point it towards the light source.

YMMV--I know this is actually kind of controversial

[chris_livsey]

Looking at reviews I came across this:
Quote
While still not compatible with Windows Vista or Mac Intel-based
machines, Sekonic's L-758DR system is a great asset for digital photographers who need exacting control of their
exposures.
End quote
From:
http://www.sekonic.com/images/files/...2007-light.pdf

It is surprising that the software has not been updated.

I am a reflected light man and still use my Minolta Spotmeter. I have no issue with incident if it works for you but I'm an A.Adams man at heart.

Given the cost and complexity of these excellent tools I am constantly surprised by how well my M8 does left to its own devices. That may be because I recognise situations where I know it will struggle and take appropriate action. I would be interested in figures showing how accurate and consistant the shutter speeds are on the M8 in order to estimate the value of 1/10th of a stop meter accuracy. Any work done on that anywhere ?

[ammitsboel]

Hi Chris,
The Sekonic software is compatible with mac(intel based) and the newest OS.
The new version is on the website.

/Henrik

[chris_livsey]

Henrik

Thanks for the clarification, more tempted now

[ljclark]

If the incident meter has a real dome (not one of those vestigial white bumps) it is intended that you hold the meter at the subject's position and point the meter at the camera. This is especially true when the subject is side-lit or back lit, since the dome approximates the balance of main light, shadow, and fill light falling on a three dimensional object. Take a white ball outside into the sunshine. Holding the ball at arm's length slowly turn a complete circle and watch the fall of the light on the ball. (You might consider bringing a couple of iced-down beers, since there can be used to distract your neighbor when he comes outside to see what you're up to.)

This is as per Sekonic's directions: "Measure with the lumisphere aimed in the camera direction at the position of the subject." Further: "Lumisphere is used to measure people and buildings and other such solid objects. Measurements are basically made by the method of measuring with the Lumisphere aimed in the camera direction (more precisely, in the direction of the lens axis) at the position of the subject.

Posters have described using a flat disk instead of the dome. This is commonly done when shooting flat objects (copy photography). With the L-558 series meters, this is done by retracting the dome into the meter head.

The other purpose of disk measuring is to establish lighting ratios. In this case the disks ARE pointed to each light source, the readings recorded, and then the appropriate ratios worked out. This can be very important in studio and motion picture work where you need to establish a consistent lighting ratio over the course of the shoot.

So that's the deal...

-- Dome faces camera for standard 3D shooting
-- Disk faces camera for 2D copy work
-- Disk faces light sources for working out lighting ratios.

Also...If you are shooting Mt. Rushmore, you need not climb up and hold the meter in front of Mr. Lincoln's nose. As long as the characteristics of the light are the same where you measure as it is at the subject, things will work. This may be the argument for those "point it towards the light" proponents.

And also -- read the manual. I'm sitting here with manuals for Sekonic L558R, L-408, L-308S, L-398M, and L-208, plus a Minolta AutoMeter III and a Gossen Digisix. There is even a lovely illustration on page 3 of the L-398M manual that shows the effect of back light, main light, and fill-in light on the Lumi Sphere. (They all basically say the same thing.)