Perplexed on Aperture Choosing with Sekonic Meter

[revup67]

In the following studio scenario I have 2 x Elinchrom softboxes (400watt) series set at 2.0 which is the lowest light setting placed at 45 degrees in front of subject at approximately3-4 feet away. The setup is in a garage with minimal ambient light from the front of the garage's small windows in which it appears the soft boxes are overriding. I am using a Sekonic L-358 meter on the cordless flash setting which means it is put in the queue and waits for the burst of strobes (2 softboxes) to offer up a reading. I can increase the shutter or decrease the shutter and at 1/200 I am at 7.1. The problem is for the portraits I would rather use a wider aperture such as 4.0 (Using the canon 5D Mark III and 100mm 2.8 L USM Macro with IS). Unfortunately in cordless flash mode you can only work the shutter and the Av changes with it on the fly. I'd rather place 4.0 and see what the shiutter should be however I am thinking hi-speed sync at this point if the Elinchrom set up offers this (it may). I would be curious to any other options thought you may have such as pulling the soft boxes back further (?) to obtain that wider aperture. I've attached a sample of a portrait of a couple I shot. This was my very first session with the Elinchrom setup. I also had a 580EX about 8 feet high set at rear/left at 1/4 Manual to increase highlights in hair. Open to any thoughts or should I not be concerned with the 7.1 setting for portraits?

 

[pwp]

To be honest I scarcely ever use the flash meter any more except maybe when I'm getting ratios right. It's quicker to check the display & the histogram. You quickly learn.

Why don't you read up your Sekonic user guide?
http://www.sekonic.com/Support/InstructionManualUserGuideDownload.aspx

If you want to shoot at a wider aperture, just turn down the output of your Elincroms till the output matches your chosen aperture.

-PW

 

[Gre34]

I use elinchrom, but not the 400s. I'm pretty sure you can't do hi speed. The thing is your strobes have no ttl. If I have understood your question correctly, you are going to find it difficult to make the strobes dim enough to go that wide. Also with such a slow sync speed compared to the strobe flash interval, you won't be able to use shutterspeed to control exposure. Your best bet is as you said to move the strobes back and also try reducing your ISo to 50. As for the sekonic, generally holding the mode button and spinning the dial should let you choose whether to select shutterspeed or aperture.

 

[revup67]

PWP - wrote:

If you want to shoot at a wider aperture, just turn down the output of your Elincroms till the output matches your chosen aperture.

thanks, but as mentioned I already had where I state:

set at 2.0 which is the lowest light setting

. I've gone through the entire user manual as well under "cordless flash" use. Unable to find anything on how to use cordless flash to determine F stop then apply shutter speed.

 

[revup67]

Gre...good idea on the ISO 50 I might try that one. The Sekonic does support IS0 metering as well as the 5D III

 

[wickidwombat]

If iso50 is not enough pop on a cpl filter that will drop the light more but personally I'd be aiming for around f8 with studio strobes I also can get the elinchrom lights to high speed sync using the phottix Orin's but I usually go with speed lights for this these days since they are more portable

 

[dickymint]

When shooting strobes in studio, I would always try to aim for f/8 to f/11. Your lenses are at there sharpest around those figures. Tbh I can't see why you want to shoot at f/4?
Set your camera to f/8, set shutter speed and use the 358 to ascertain the strobe out put to match.
Minty

 

[revup67]

Minty - In watching the Joe McNally One Light series he uses the Nikon 200mm F/2 @ 2.0 and 5.6 on the 70-200. He does not use F8 or F11. I've calibrated all of my lenses with FoCal so I do know the sharpest points on each of my lenses. Strangely they are not always F8 as with my 100mm USM L IS Macro the sharpest point is 5.0. With the 2.0 and its narrow DOF, he gets focus on the model's eye and everything else for the most part has a softer look. In shooting non youth portraits (my mainstay) that is the look I am seeking and realize you can control some of this with PS5 or PS6. F8 and F11 offer too much def as well as the background may be more in focus. Those are the reasons I am shooting for wider Av's

Wicki..ahh..another good idea is the CPL as you suggest or perhaps the ND filter along with ISO 50..I think that would do the trick.

 

[Studio1930]

I also use FoCal and I can tell you that some lenses are better at f/8-f/11 than others. My 135 f/2 is pretty good all the way up to f/10 or so but my 200 f/2 is much happier in the f/2.0-3.5 range which is right where I use it the most. ;D

(Note: both lenses are fine at f/8 but do better at other apertures.)

 

[Maui5150]

Just throw on an ND filter.

Sometimes when it becomes too hard to adjust power output/ISO the easiest was is to just throw on a filter

 

[awinphoto]

Flash and large aperture is always a challenge... You can do a few things... lower the flash power, which you did, you can move the light source away, which will reduce the light... Moving the light as little as a foot away, depending on the location of the light, may reflect a large drop of light especially since your light is already modified. You can drop the ISO to Low (50), which I do... ND filters is another way to go, but then it makes it harder to view in the VF... Some other factors... Use a large softbox so the light disperses even more in the softbox... then you can even move the light back some and have the same size catch lights but much more dramatic change... Erm... You can put more white sheer fabric on the softbox so the light has more diffusion to go through (less light), but watch the weight as it may make the softbox for top-heavy... Anyways I hope this helps.... It's usually pretty rare when people want less power from strobes, but it does happen from time to time, so I hope this helps.

 

[revup67]

Awin - yes I plan to use an ND and drop to ISO 50. I do have reflectors on stands with arms and may place a reflector in front of the soft boxes (or one for more dimensional effect) to reduce light, then tweak output upward on the strobes til I reach a wider Av with proper lighting. I've got a 3 stop ND on hand so it may do the trick along with above.

 

[erwinrm]

+1 on the ND filters.

Another alternative is to move the lights closer, and just shoot using the modeling lights.