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Mary Burgy

focus check

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This is in focus, right?

I am struggling b/c my monitor is large and I think I am pixel peeping.  No edit yet

 

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2N6A4380 copy.jpg

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If you want both eyes to be in focus, you'll need to stop down, since each eye is on a different focal plane. The good news is your focus is on the eye closest to the camera, so you are good.

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I was at 5.6 at 39mm.... I think I may have just slightly missed focus b/c I would think the DOF was deep enough (but then again I didn't calculate it)

 

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This isn't missed focus. I think what happened is you were a bit too close to the subject, since you were at 39mm, and that's not too far off from 35mm. This decreases the Depth of Field. Had you been at 70mm (and standing further back) f/5.6 probably would have been fine. At the distance you were at, I'm thinking f/11 would have helped somewhat, maybe f/8...but am leaning towards f/11 or so.

Either way, composition-wise and technical-wise, you are fine in focusing in on the closest eye.

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Very true... I may need to shoot at f8-f11 for kiddos to help with this.  Thanks for the tip.

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Don't be afraid to use those smaller apertures. Play around with them. Just keep in mind, when you use a smaller aperture, you'll need to increase flash power. So if you were at, say 1/8th power @ f/5.6 then you would need to increase your power to 1/2 to get f/11. If you still don't have enough "Umph," either move the flash a bit closer or get a bigger light.

It is very normal to be at f/11 for your main (key) light and f/8 for your second (fill) light for shots like this. Once you figure out your recipe, there will be a whole new world opened up for you.

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Yeah, I use a huge PLM to help with even lighting too.  I was trying to blur out the texture of the BG a little b/c it is an outdoor mat.  Normally I try to shoot studio around 6.3 or so and don't tend to have issues.  But I don't shoot kids this small often so I probably was closer than normal, reducing my DOF.

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On 3/30/2018 at 4:34 PM, Brian said:

It is very normal to be at f/11 for your main (key) light and f/8 for your second (fill) light for shots like this. Once you figure out your recipe, there will be a whole new world opened up for you.

I apologize in advance for intruding in question opened by Mary here, and probably this is stupid question but  @Brian.. Aperture value is supposed to be for lens opening right ? (I don't know .. i'm still on single on camera flash ) but this different f stops for light got me confused. What am i missing here? even if you have 2 lights, you are going to have single lens .. and i'm totally confused as how can you have f/11 and f/8 ?

or are you saying f/11 & f/8 in terms of stop from exposure/light perspective .. so you mean .. have main light on lesser stop and increase light stop on second light ?

Sorry for confusion.. But i'm trying to figure out getting flash off camera .. and adding another flash and i'm not getting this point hence i'm raising this question. 

Edited by rahullele
grammer fix

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My flash/strobe settings aren't like that, but some light meters tell you to set the flashes according to f-stops.  Mine is based on power levels.

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There are TWO Exposure Triangles. One for natural light and one for flash / strobe photography. 

When it comes to flash photography, not only does aperture relate to depth of field, it also controls your flash power. A two light setup, say f/11 and f/8 is a very typical one. That means that the main (key) light’s power is one stop greater than the second light. That’s a 2:1 Lighting Ratio  

The Golden Rule of Flash Photography:

Aperture controls flash power-

Shutter Speed (and ISO) controls Ambient Light.

If you are setting OCF’s manually, your camera’s built in meter is COMPLETELY WORTHLESS when it comes to manual flash photography. That’s because the camera’s meter is basing its recommendation on existing (ambient) light. Your flash hasn’t fired yet, so there aren’t any readings. The only exception to this rule is if you are using TTL (Automatic) flash that uses algorithms to set flash power based on the manufacturer’s way of thinking.

So say you have one light at 1/2 power and another at 1/4 power. That is a one stop difference which means the “umph” of the key light (or intensity of the light) is one stop brighter than the second (fill) light.

Why f/11? Because the optimum exposure from the light of that key light hitting your subject requires you to be at f/11. If you had a hand held meter and put it to your subject’s chin and pointed it towards your flash, and took a reading, “proper exposure” would be f/11. If you set the main light to 1/8 power instead of 1/2, that’s a two stop change, in which case you would be at f/5.6. (Less umph from the flash means you need more light hitting your sensor to obtain proper exposure, thereby opening up your aperture. 

That’s why if you want to be at f/2.8 for shallow DoF for those fuzzy-wuzzy sleeping baby photos that you are at 1/32 power or even 1/64th. 

Zack Arias has an excellent Creative LIVE video that explains it better than I ever could. Let me find it. 

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Here is the video. Watch it multiple times until it sticks. ;)

 

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So to answer your question, no you don’t have two aperture settings. I know it appears like you take two photos, one at f/11 and one at f/8, but that’s not the case.

When assigning aperture values to lights, it’s a way to get around different manufacturer’s power output for various flashes / strobe. I could tell you to set your Nikon/Canon whatever to 1/4 power. I could also tell you the same on say a Alien Bee or Profoto Flash. Since the light bulb from the Bee or Profoto is physically larger, it’s throwing out a firehose worth of light compared to a garden hose from your Canon / Nikon Flash. Understand? It’s a way to keep things simple and consistent. Since a Profoto Light is way more powerful than a pop-up Flash, telling you to set a Profoto light to 5.0 will produce different results than your pop-up flash at 1/2 power. It’s easier to use an aperture Number than a power setting number. Of course if it’s just you and your private studio and it’s your lights, you can fiddle and figure out your recipes on what looks good. If you want to try and explain your lighting setup and power settings to someone else, use the universal light ratio numbers, written with Aperture Settings. 

Clear as mud? 

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I also mentioned distance in my original answer. That statement was based on something called the Inverse Square Law. 

The inverse Square Law dictates that you lose 75% of the intensity of the light as you double the distance between your subject and flash. So if you have your flash two feet away from your subject, and move it four feet away, you have about 75% less “umph” to work with than before. Same thing goes for when you go 4 feet away to 8 feet. But there lies a clue 4 to 8 feet, is pretty good wiggle room. So if your light stays within that 4-8 feet range, you shouldn’t have to mess with your power setting or aperture. 

Think of placing your light on a big dartboard. In the center is your subject and the “rings” are where you put your light. If you obtain proper exposure AND keep the distance the same from your light to your subject, your aperture and power setting stay the same. 

Here is an example. You have a favorite PLM and your photos look awesome when the light is 6 feet away and you shoot at f/4. If you put your light on the opposite side of your subject, AND KEEP THE SAME DISTANCE, the only thing that will change is the placement of the shadows and overall look. Your aperture& flash power stay the same, since the distance is the same. That’s the Inverse Square Law in action. That’s also the reason that flash photos look so “icky” when you use a stupid pop-up flash standing 8 feet away from your group photo. :) 

i realize this is a lot of info. If you care to discuss this further, hit me up in the DSLR Bistro. 

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Wow... thanks for all of this information.  I can't wait to sit down and watch the video.  I just purchased 3 Einstein lights and am eager to try using a light meter!

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Okay - So I just played with a 3 light set up.  I used a large PLM and reflector up front and she read 5.6.  Camera was set to 5.6.

I lit her backside at f4 (per a handheld meter) b/c I wanted it a stop of light lower.

What I cannot wrap my head around is why f4 is less light.  I still think of it as aperture... and f4 means more light when it comes to that.  What is a logical way I can understand why a reading of f4 is less light?  I know my camera is still set to 5.6.  I like to full understand instead of just go through the motion.

 

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Because you are still thinking along the lines of shooting natural light. 

Aperture Controls what POWER SETTING you use. There is less light coming out of your Einstein 640 so you open up your Aperture to let more light in. If you increase your power in the E640, you would go to f/5.6 to compensate. 

Also, do not be fooled by the modeling light. I will say it again, you can not use your camera’s built in meter to figure out what power setting to be at. For that, you need a HAND HELD METER, like a Sekonic L-358 or something newer. 

Of course with practice and experience, you can get away without using a hand-held meter. Once you figure out moving the power setting to ____ and use this thingy with this other doohickey and put that whatchamacallit over there and have your subject do/turn ______. LMAO!!

I know some photographers that do this on a regular basis. They have been doing it this way for years; it’s very much like a Musician playing by ear. They can play something, but couldn’t tell you what key they are in or what chord progression that they used. Same thing with photography and light setups, thise can’t tell you WHAT they did to produce that photo  

My way of doing things is very methodical and theory based. Once you get “Natual Light Methods” out of your heads will you start to understand. It’s really not that hard, it’s just a new skill set. The main reason is your light source is usually 6-8 feet away vs 93 million miles away. 

One quick way is to look at your eyes in the mirror with a bright light nearby. What happens to your pupil? They get smaller, just like the aperture blades in your lens. (F/11, f/16, etc.) 

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