The great John Denton, master of flash, comes to the south coast on 20th May and I'm booked in for a full day on-location model shooting with him!!!!
John is a memeber of the SWPP, Society of Wedding and Portrait Photograpers, so every couple months there's a new lighting course with a top photographer.
With luck I'll be able to keep up with all the info and learning oportunities that John will be throwing at myself and the twelve or so other during this top of the range one day course. I've been a fan of Denton's portrait style for a number of years and this is going to be the highlight of my year.
ASAP I'll be posting up some of my results so you can see what I've learnt and how I coped with the pressure of being put on the spot with a top UK model, a location I've not previously sussed out, and lighting which I shall try to be prepared for but am not sure of - might be mine or could be John's ideas.
Really looking forward to this challenging day which every self-respecting portrait photographer should be scrambling to get onto - can't wait!!!!!
Sunday 12 May 2013
Sunday 13 January 2013
Flash Vs LED torch
A torch and LED lighting capture a part open book proving that low powered lights can yield amazing results.
Let's look at how substituting one of the light sources with a low powered flash will help us understand the relationship of continuous lighting with that of a flashgun, an understanding of which we might one day need while on a location portrait-photoshoot when we want to capture a lovely sunset as a background behind the subject.
A flashgun exposes our subject in around 1/1,000th of a second regardless of the shutter speed, (below the sync speed of 1/200th). Meanwhile, we are using those same shutter speeds to control the intensity of the LED light source - longer means brighter and shorter gives a darker image. You might or might not notice that the flash exposure never changed, but more of this a moment.
A typical closeup or table top still life scenario might be :- We need a good depth of focus for our subject and decide on F11. The LED block at twelve inches requires a shutter speed of 1 second. This is okay for the flash as that is all over and finished, as we know, in 1/1,000th - it doesn't matter that the shutter is still open so it can carry on capturing the LED lighting.
This means we could make the exposure time longer to effectively create more light from the LED's without effecting the flash exposure. This is a hint that flash and continuous lighting are governed via separate camera controls - flash with aperture and continuous light via shutter speed. For instance, a longer exposure would give us more time to move the LED light slowly around the subject and we could eliminate all shadows. I say slowly as the exposure is one second so each position of the light needs to be for one second otherwise that part of the overall exposure will be too dark. Moving it slowly will allow that part of the subject to look balanced, while a faster movement will under expose.
So it looks like speed of movement from the light source or shutter speed governs how intense the light is.
We could even leave the shutter open for thirty seconds, which most digital cameras are capable of, and use the LED on/off swith to make our exposure of one second. This is assuming we are in a dark room, shed, skittle alley, etc.
We might also, during the same exposure, switch the LED back on with it in a different position and illuminate the shadow side of your subject from just a little bit further away thereby creating a softer shadow and we start to appreciate what lighting ratios are all about.
Meanwhile, our flashgun could also be moved, closer for more light or further away for less. We can also vary the softness of a flash by keeping to the same distance, doubling the output and bouncing it into a handheld reflector, or off a white wall, piece of card, even a sheet of newspaper, or the inside of a helium party balloon which is a matt finish alluminium and makes a superb reflector when taped over a piece of cardboard.
Same as the LED the flash can be moved and exposed several times during a thirty second exposure. Fire it once straight on from the right for a sharp shadow, then move it to the left side at the same distance but this time bounce it into a reflector and the shadows become softer by between one stop and two stops.
By now it should have become clear that shutter speeds control continuous lighting while aperture controls the flash. What else can control the flashgun? Distance, closer for more light, further away for less intensity. Then there are all the different powers from full whack all the way down to 1/128th power.
Another consideration is the aperture of F11, the higher the number the lower the lighting power from both continuous light and flashgun, but is going to throw a spanner in the works if we want to stick with the F11 we originally wanted for our required depth of focus.
A lower aperture such as F5.6 means we have less time to play around with our lighting, or does it? No, we merely shift our lights to exactly double the distance and we are right back to using all the timings and scenarios above. There is a complicated formulea which we don't neeed to confuse ourselves with called inverse square law but thankfully the way F numbers are worked out means we get exactly the same lighting power by doubling the distance and dropping two stops.
Hope your not too confused but my Yeo Photo Group camera club will be running through this several times on Tuesday evenings and will be using this basic information many times at during the next twelve months.
Let's look at how substituting one of the light sources with a low powered flash will help us understand the relationship of continuous lighting with that of a flashgun, an understanding of which we might one day need while on a location portrait-photoshoot when we want to capture a lovely sunset as a background behind the subject.
A flashgun exposes our subject in around 1/1,000th of a second regardless of the shutter speed, (below the sync speed of 1/200th). Meanwhile, we are using those same shutter speeds to control the intensity of the LED light source - longer means brighter and shorter gives a darker image. You might or might not notice that the flash exposure never changed, but more of this a moment.
A typical closeup or table top still life scenario might be :- We need a good depth of focus for our subject and decide on F11. The LED block at twelve inches requires a shutter speed of 1 second. This is okay for the flash as that is all over and finished, as we know, in 1/1,000th - it doesn't matter that the shutter is still open so it can carry on capturing the LED lighting.
This means we could make the exposure time longer to effectively create more light from the LED's without effecting the flash exposure. This is a hint that flash and continuous lighting are governed via separate camera controls - flash with aperture and continuous light via shutter speed. For instance, a longer exposure would give us more time to move the LED light slowly around the subject and we could eliminate all shadows. I say slowly as the exposure is one second so each position of the light needs to be for one second otherwise that part of the overall exposure will be too dark. Moving it slowly will allow that part of the subject to look balanced, while a faster movement will under expose.
So it looks like speed of movement from the light source or shutter speed governs how intense the light is.
We could even leave the shutter open for thirty seconds, which most digital cameras are capable of, and use the LED on/off swith to make our exposure of one second. This is assuming we are in a dark room, shed, skittle alley, etc.
We might also, during the same exposure, switch the LED back on with it in a different position and illuminate the shadow side of your subject from just a little bit further away thereby creating a softer shadow and we start to appreciate what lighting ratios are all about.
Meanwhile, our flashgun could also be moved, closer for more light or further away for less. We can also vary the softness of a flash by keeping to the same distance, doubling the output and bouncing it into a handheld reflector, or off a white wall, piece of card, even a sheet of newspaper, or the inside of a helium party balloon which is a matt finish alluminium and makes a superb reflector when taped over a piece of cardboard.
Same as the LED the flash can be moved and exposed several times during a thirty second exposure. Fire it once straight on from the right for a sharp shadow, then move it to the left side at the same distance but this time bounce it into a reflector and the shadows become softer by between one stop and two stops.
By now it should have become clear that shutter speeds control continuous lighting while aperture controls the flash. What else can control the flashgun? Distance, closer for more light, further away for less intensity. Then there are all the different powers from full whack all the way down to 1/128th power.
Another consideration is the aperture of F11, the higher the number the lower the lighting power from both continuous light and flashgun, but is going to throw a spanner in the works if we want to stick with the F11 we originally wanted for our required depth of focus.
A lower aperture such as F5.6 means we have less time to play around with our lighting, or does it? No, we merely shift our lights to exactly double the distance and we are right back to using all the timings and scenarios above. There is a complicated formulea which we don't neeed to confuse ourselves with called inverse square law but thankfully the way F numbers are worked out means we get exactly the same lighting power by doubling the distance and dropping two stops.
Hope your not too confused but my Yeo Photo Group camera club will be running through this several times on Tuesday evenings and will be using this basic information many times at during the next twelve months.
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