Sekonic L-758DR Questions

[hugebob]

Hi All,

I just picked up a Sekonic L-758DR and I'm getting

acquainted with. But, I have some questions. In flash

measuring mode, if I move past 1/1000 sec. the

subsequent shutter speeds are 1/75, 1/80, 1/90, 1/100,

1/200 and 1/400. I'm curious as to why. The manual calls

them "intermediate" speeds. Intermediate to what speeds

and why are they at the end of the range. I also have a

question about readout. I've seen other Sekonics where

the measured f-stops were in full stops with tenths: e.g.,

5.6.7, 8.5, etc. A meter reading of 5.6,7 equates to f7.1.

Excuse me if I don't have the precise lingo for this. A class

instructor showed us that this readout helps us

understand things better.

[wayne_f1]

<p>Tenth stops are a good plan for studio flash, we know fill ratio in our heads then. <br>

You can set the meter to read tenth stops, which Sekonic calls Full stops (plus the tenths).<br>

See manual, page 44, custom setting 3, Full Stops.</p>

[hugebob]

<p>Thanks Wayne! That's it! I'd like to force myself to remember these things.</p>

[bob_bill]

<p>Robert, that black piece of paper that was included has pull off patches to stick inside and outside of the battery compartment hatch that include the change combinations. One I find necessary is the jog wheel advances counter clockwise instead of clock wise, reversing that. Also, consider resetting the iso 2 button to compensation mode. If you know your dynamic range from 18% to highlight clipping after profiling meter and camera, set that compensation in that button and you can shoot as far as possible to the right to keep detail by spot metering in brightest area desiring detail then push comp button and it tells you your camera setting, no calculating in your head... or fingers or clicking and counting. In high dynamic range situations, will give you max detail in highlights and push shadows as far right as possible for least noise. </p>

[bebu_lamar]

<p>With custom settings the meter can select shutter speed in full stop, 1/2 stop or 1/3 stop increments. If it is set in full stop you can't set any of the so called intermediate speeds. If in 1/2 stop I think you can't set 1/80, 1/100, 1/200 and 1/400. If in 1/3 stop I think you can't set 1/75, 1/90. So those are there to allow you to set those speeds without having to change the custom settings. </p>

[hugebob]

<p>Thanks Bob! One of the first things I did was alter the direction of the Jog wheel to my liking. But, I have question on compensation. I've calibrated the meter to my camera. By "18% to highlight clipping", do you mean my highlight clipping point? If so, I set mine to +2.9 EV; just a hair below the software's findings of +3.1EV. I've set ISO2 to that value: +2.9EV. I'm confused about using this in the field, however. Are you saying that the reading given when I press ISO2 hereafter will show me what setting to stay "below" to avoid highlight clipping?</p>

[hugebob]

<p>Bebu,<br>

In flash measuring mode, as I increase the shutter speed, I expected it to increase beyond 1/1000. Getting 1/75, 1/80, /190, etc is puzzling. Also, if I change the increments of shutter speed to thirds, I lose the full stop aperature + tenths readout.</p>

 

[bebu_lamar]

<p>Well the meter can only measure flash up to the 1/1000 measuring time so 1/1000 is top for flash mode. The other speeds are there for your convenience as there are camera with top sync speed of 1/75, 1/90, 1/80 etc... If you don't need them just ignore them. Now I can see that you would need to leave the increment in full stop to get the kind of readout you want (me too) in aperture. So it even makes more sense to me to include those oddball speeds there. </p>

[hugebob]

BeBu,

 

That's perfect! Thanks!

[bob_bill]

<p>Robert, set your iso 2 to compensate +2.6-9 stops. In high contrast situations, spot on the brightest area you want detail, a white cloud for example. Hit the iso 2 button and it will compute an additional 2.6 stops to that reading taking it from middle gray which is what a spot reading shows, and taking it up to the limit of your sensor. Set your camera to that iso 2 reading with the additional 2.9 stops. You camera histogram and blinkies are based on a converted jpeg that and is a conservative setting. Trust your calibration. You can also take an ambient reading, save it as mid tone then spot and save the brightest and darkest for detail. They will show on the scale at the bottom of the meter. You can then move the scenes range within the points marking clipping points for the camera number you have selected to just get the highlight or shadow within clipping. In post, you can recover the highlights and kick up contrast because you have information. If you shot to the right, you have the highest possible shadow setting and have to fill it as little as possible, minimizing noise or muddy shadows. It will get you the best possible file. Mid tones can be altered with fewer problems than clipped whites or blacks at either end. I like it for all the above but in normal contrast situation, a quick incident meter reading and one shot and I have it. I like the accuracy, efficiency (minimal chimping), repeatability not to mention being able to concentrate on the task at hand, capturing my vision, not "taking an exposure." That expression makes it sound like that is the object of the image, it is only a small part of the capture workflow. </p>

[rodeo_joe1]

<p>Bebu is correct. The reason for those "odd" extra shutter speeds is to match a range of X-synch speeds found on old film cameras. Camera makers would push the synch speed to the maximum that could be squeezed from a shutter. 1/80th was pretty common, and other cameras managed a 1/90th synch speed. The 100th, 200th and 400th are there for compatibility with ancient leaf shutters that used the now obsolete shutter speed series of 1, 1/2, 1/5, 1/10, 1/25, 1/50, 1/100, 1/200 & 1/400. Sometimes 1/75th was thrown in for good measure!</p>

<p>The 1/200th speed might be useful to match the sluggish synch speed provided on some Canon DSLRs. Or if you have to drop the synch speed when using radio triggers.</p>

<p>The way that particular flash meter works is to emulate the camera shutter by gating the measuring time. In theory this gives you a more accurate exposure measurement by taking into account any ambient light as well. What it doesn't account for is that most mains-driven lighting flickers at 100 or 120Hz depending on the regional AC frequency used. Or that daylight can vary in the time it takes to transfer a meter reading to the camera.</p>

<p>FWIW, a normal incident reading automatically gives you a 2.5 stop "headroom", based on a 100% Lambertian reflection. Since white paper, white clouds away from the sun, white linen, whitewashed buildings, etc. all approximate a 100% Lambertian reflective surface, there's usually no need to push your DR to the limit. It's safer to have a bit in hand from a RAW exposure to allow for those odd specular reflections or trans-illuminated clouds and the like. And in a controlled studio environment the DR or Brightness Ratio should be limited by your fill lighting anyway.</p>

[hugebob]

<p>Rodeo,<br>

My Canon 5D (original) fits that bill at 1/200sec. It's a good thing that speed was included. I wouldn't have been able to keep the configuration I wanted and be able to use that speed otherwise.</p>

 

[rodeo_joe1]

<p>Robert, you need to watch out if you use radio triggers for your flash. They introduce a delay that can (does) require you to lower your synch speed if you want to avoid a dark band at the lower edge of the landscape frame. The only way you can use the maximum X-synch speed is to use a hardwire coupling to the flash, or to use optical slaving from a hotshoe flash. IME, when using radio triggers a synch speed of 1/160th is about the top limit for a 5D.</p>

[hugebob]

<p>Bob,<br>

Thanks for the tip! That's quite a bit there. My mind is sufficiently blown (not too hard to do, LOL) but intrigued. I guess I'm trying to put what your saying to field use. I think I'll take bone up on midtone and memory functionality and take some time this weekend to go out and try what you're suggesting. That should clear the cobwebs. I'll be back with questions for sure.</p>

 

[bob_bill]

<p>Robert, I like the benefits that meter provides. Precise clipping and dynamic range of that camera's sensor. When wanted, you can maximize the file by tonal placement of shadows or highlights or decide where to place your midtone. For me, a meter gives more accuracy, efficiency-less chimping and faster setups, and repeatibility not to mention peace of mind allowing me to concentrate on capturing my vision, not "taking an exposure." Sekonic says your camera meter is usually right, but for some, usually right isn't right often enough. As a fisherman, I am constantly checking knots, leader for nicks or abrasions or damage to the hook because the next fish could be the fish of a life time. Same in photography. I have taken some shots of a lifetime, some by the seat of my pants and thankfully, I nailed them. I find the "extra time" it takes to meter is at least off set by the time chimping and adjusting, not to mention the time spent in post and potential deterioration to the file by large adjustments. If you have any questions, feel free to email me direct. </p>