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No flash, one flash and two flashes
Antonio Correia
Registered Users Posts: 6,241 Major grins
I have been practising with my two flashes, using the 20D + ST-E2 + 24-70 mm on a tripod and the two flashes
a) 430 EX on the right bounced to a white wall to the right. The wall was 1m away from the object and the flash at half way.
b) 580 EX II was in my hand as well as an A3 sheet of strong, solid white paper
1 shot
No flash
To begin with I made a shot with the "correct" exposure.
I set the aperture to f/3.2 and found the speed to be 1/40.
As the camera was on the tripod I didn't have blur problems.
I used the timer to minimize the shake.
2 shot
No flash
I kept the aperture 1/3.2 and changed the speed twice down.
To the left of the scale on the viewer, I mean.
Now the speed was 1/100.
The goal was to get a dense and "dark" background to make the statue to pop when using the flash.
After all I am thinking of shooting a bride instead of the statue...:wink
3 shot
With one flash.
The one which was standing on the tripod, on the right.
4 shot
With both flashes.
While the timer was running I moved nearby and direct the flash against the white sheet of paper.
On the Exposure Value I went down, vertically, using one aperture and minimizing the light with a faster speed.
With this small exercise I want to practice the shots using 2 flashes making the subject to pop from a dark background.
I have used f/3.2 to have a shallow depth of field but not so shallow as 2.8
the central point was used to get in focus.
However we can see that the 2 last pictures don't have a so dark background as the third. It is because I have been working a bit on them in CS3.
I must learn to select areas in CS3 quickly.:wink
Histograms here are not important to look at because I manipulated the image in two separates subjects: background with the speed and the statue with the power of the flash lights and the aperture.
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a) 430 EX on the right bounced to a white wall to the right. The wall was 1m away from the object and the flash at half way.
b) 580 EX II was in my hand as well as an A3 sheet of strong, solid white paper
1 shot
No flash
To begin with I made a shot with the "correct" exposure.
I set the aperture to f/3.2 and found the speed to be 1/40.
As the camera was on the tripod I didn't have blur problems.
I used the timer to minimize the shake.
2 shot
No flash
I kept the aperture 1/3.2 and changed the speed twice down.
To the left of the scale on the viewer, I mean.
Now the speed was 1/100.
The goal was to get a dense and "dark" background to make the statue to pop when using the flash.
After all I am thinking of shooting a bride instead of the statue...:wink
3 shot
With one flash.
The one which was standing on the tripod, on the right.
4 shot
With both flashes.
While the timer was running I moved nearby and direct the flash against the white sheet of paper.
On the Exposure Value I went down, vertically, using one aperture and minimizing the light with a faster speed.
With this small exercise I want to practice the shots using 2 flashes making the subject to pop from a dark background.
I have used f/3.2 to have a shallow depth of field but not so shallow as 2.8
the central point was used to get in focus.
However we can see that the 2 last pictures don't have a so dark background as the third. It is because I have been working a bit on them in CS3.
I must learn to select areas in CS3 quickly.:wink
Histograms here are not important to look at because I manipulated the image in two separates subjects: background with the speed and the statue with the power of the flash lights and the aperture.
. . . All the best ! ... António Correia - Facebook
0
Comments
I did not see where you mentioned whether this was shot with ETTL or not, and whether the camera was in Manual Mode, or Av mode?
I think for what you are wanting to do, Manual Mode with ETTL will work best. This will give complete control over the illumination of the foreground and the background. If you shoot in Av mode, the camera will expose the background correctly, and the flash will illuminate the foreground. You may find you need to use High Speed Synch if you need shutter speeds faster than 1/250th however.
In your images, you still have not gotten as much pop to the subject as I think you can need for the best separation. This can be easily done with the setup you specified, without needing selections in Photoshop.
In Manual Mode in ETTL ( may need HSS) you can drive the background very dark as you desired, and still have bright subject.
What distance will you be from your subject? The closer you are, the easier to overpower sunlight.
Moderator of the Technique Forum and Finishing School on Dgrin
Yes it is ETTL and Aperture priority because I wanted to keep a wide aperture.
EXIF here.
Thinking a bit of what you just wrote I should say that Manual is a good option indeed if I increase the ISO in order to get an even highter speed, to darken the background without influencing the light on the statue (within certain limits as Neil says
With a hight ISO I would be with the same aperture and a smaller speed.
Then may be I'll need to increase the power of flashes a bit ...
I shall do it again - I hope - and I will take a note about the FEC.
Then - as you said - I will not need to duplicate layer, etc.
More work on the camera, less on the computer. Pretty good option. I like this.
May be I am afraid of seeing the statue too dark ... On the other way, what we see in camera is NOT what we see in the computer.
Exposing to the right and to the light (Kenn
Even in the computer I have another little problem: I always see the pictures lighter than in CS3.
But that is another matter.
Thank you Jim for commenting. I do appreciate your opinions and tips.
(to myself) Now I am thinking ... If I keep the speed and increase the ISO I'll have more detail in the background... So, this option is good for interiors...
Am I thinking correctly ? Is it what Neil said in his last post ? Huuuummm. Have to go and read again... (to myself)
If I understand what Neil is saying in his thread correctly ( see his sixth bullet point ), he is saying what I said above - shoot in ETTL and with the camera in strictly Manual Mode so that you dictate the ISO, Shutter Speed and Aperture, and lett ETTL control the flash to do the correct exposure.
This is what allows such complete control over the balance between ambient and flash exposure.
Moderator of the Technique Forum and Finishing School on Dgrin
Jim,
I will repeat the exercise.:D
I came here because I have forgotten to thank you by pointing me that 6.th point on Neil's site.
Thank you Jim.
I shoot in Av with flash too - it is easy and quick, but Manual Mode with ETTL is the cat's meow for control of ambient versus flash.
If you raise your ISO up higher, you will capture more ambient light, just as if your dropped your shutter speed way down slow.
Neil does an excellent job of demonstrating this ability to capture ambient light, but at a lesser strength than the lighting from the flash on the main subjects. Just like in Theatre - shine the light on what you want the theatre patrons to see. With off camera flash, this really allows you to control what the viewer is supposed to look at. I'm a believer! This is really the same message that comes from the Strobist, but there they are devoted to strictly manual flash as well. As long as you have the time to set up where the subject is going to stand relative to the flashes, that will also give similar results because you control where the light is and is not.
Moderator of the Technique Forum and Finishing School on Dgrin
Here is my approach:
Put the camera in manual mode.
Adjust the aperture for the DoF I want.
Adjust the shutter and ISO to put the ambient exposure where I want it.
Remember to take into account your max sync speed.
Turn on the main strobe. In a bright enviroment I start at full power; in an darker environment I start at 1/4 power.
I then measure a pop or two of the main strobe with an incident flash meter to determine how far it is from my desired aperture.
Adjust the power on the main strobe to match my target. Say my target aperture is f/5.6 and the strobe measures f/8 then I know it is one stop hot so I can turn it down by one stop, e.g. 1/4 power -> 1/8 power.
Determine my target aperture for the fill strobe. If I want my fill strobe to be one stop darker and my main is at f/5.6, my fill target is f/4.
Turn off the main strobe, turn on the fill strobe, and adjust the fill to the target.
Finally, turn on both strobes and measure the combined exposure.
Adjust the camera appropriately and fire away.
If you don't have an incident light flash meter, the easiest substitute I have found is a stand white sheet of paper. When chimping, I find it much easier to judge where I want white to be on the histogram than middle grey.
Kenn, how are you ?
Exquisite and laborious approach !
Thank you for the tip.
Getting better after a flu came through our house last week. Life has been a bit crazy lately; I am hoping things will settle down by this weekend so I can get to a few photo projects I have planned.
Its not actually not particularly time consuming or difficult and it is 100% reproducible so I get what I want on the first try. I particularly like this approach when setting lights up for a portrait because I can get everything set up before my subject sits down. ETTL is great for candids and dynamic situations but for any formal set up photo I'll go for the consistancy and reproducibility of manual flash power every time.
As I often say: without Health we are nothing.
This is why I wish Health to people. It's the best. Even better than photography itself !
Hope your familly and yourself get better very soon.