Top tip: carry a white plastic shower curtain, foil emergency blanket and a roll of tape in your bag in case there are only dark walls, or some weird colour cast. Got me out of a few tricky situations! You can also use as a diffuser for sunlight, a flag, or sit on it if it's wet.
The inverse square law follows from the geometry. Imagine you have a lightbulb that sends out light in all directions. Now imagine a sphere at a distance 1 meter, and another sphere at a distance of 2 meters. The surface area of the sphere at 2 meters distance is four times as large (remember 4*pi*r^2 is the area) as the sphere at 1 meter distance. The same light that touched the "1 meter sphere" now is spread out over four times as large an area of the "2 meter sphere", which means that the light intensity is one quarter. At a distance of 4 meters, the light now has 1/16 the intensity because the area of the "4 meter sphere" is 16 times larger than it was at the first "1 meter sphere".
Hooray for Team Physics! As one gets further away, the drop off becomes linear - every 1% increase in distance leads to a ~2% drop in light. So whereas going from 10m to 20m drops the light by 75%, going from 100m to 110m, 10% further away, drops it by 20% (21% for the pedants). Thank you Gauss and Newton!
Martin, these videos and your presentation are great! Your videos on the 5D and 6D inspired me to buy a used 5D mkii and I love it. This video as well, it is remembering the basics of light and capture. Thanks.
Just what I needed as doing my first wedding gig this week. Thanks for explaining this so well, love your approach no snobbery or nonsense. Will be working my way through all your videos.
Re the Inverse square law. The math behind it is based of a point light source but you can apply the theory to diffused and other light sources. For the inverse square law as you double the light source to subject distance the intensity of that light reduces by 75% or to 1/4 of what it was at source. In photography terms you lose 2 stops. You have 2 subject in a photograph / portrait the person in the frame and the background, the closer you have your light source the faster the fall off of light will be and darker the background will become, the further away the more gradual it will be and the lighter the background will be, it's all about distance. Trying to light a large group of people you need to work the light further away so the exposure is even or more even across the group. Want it to be soft, you will need modifier that makes the light larger relative to your subject and you will need more flash power. The best way to get to grips with it is to shoot example images, we work in a visual art from after all.
I think you really have a unique style. A lot of portrait photographers have very similar looks to their pictures. But you, I don't know if it's the lighting or the editing, but I think I could recognize your work right away every time.
Flash videos! Yes! Not sure why I struggle with flash settings but it all seems quite complicated. I’ve purchased 2 canon flash heads and have never used either one. I really gotta spend some time sorting it out.
Really useful, thank you Martin. Knowing very little about interior portrait photography, I assumed that you used complex and expensive pro setups to get such a nuanced lighting effect...
Just discovered your TH-cam channel a couple of days ago. I have to say your portraits have the most amazing look to them; really beautiful. Subscribed.
Nice light stand! I recently purchased 2 light stands to go with my setup but alas, they are heavy and quite a pain to take on the bus/subway. That Manfroto would go right on to my backpack on the other side of my tripod and life would be easier.
This is exactly the type of video I've been looking for... For about a year. FINALLY. THANK YOU! ❤🤠 📸 Two things. 1. Please show us HOW you shoot in a tiny room with one speed light. 2. Please show us HOW to edit on free software (ex. Canon, Nikon) without using Abode subscription apps.
Would it be wise to have either one wall (the bounce) painted white and the rest darker/black for more control or all white, im setting up a little 'studio' and like the idea of the bounce.
Good explanation. I have a lot of lenses, but no flash. I think I should add one. I like taking portraits at sunset, and I think it will help get the effect I want. Those pictures you showcased here are amazing!
Great explanation and very practical. I've bounced speedlights against back walls on many shoots. Here's a physics and light question: When the light hits the back wall and bounces back, doesn't the back wall become the new source of light and a new light falloff calculation begins there, at its new 'source' relative to the subject? Or, is the distance from the flashhead to the back wall and then to the subject, the total distance of the light falloff calculation? Lastly, how would you handle it if the walls were painted a strong color? In the name of simplicity, would you go umbrella or softbox?
Hi Bob, as far as I know the rate at which light reduces starts from the point of origin, inverse square law as i understand it covers the spreading of light and the rate of reduction. so the spreading part would start again i suspect from the wall but the rate of reduction starts from the place the light first came out of. IF the walls are painted you could use an umbrella or softbox if the space is big enough but they would have to be 6 or 7 foot to get the same look. You could if you want to save money hang a white bed sheet even on the wall. you could hang a white sheet as a modifier as well, so somethign like umbrella to avoid hot spot then hang a large bed sheet to diffuse the light. that would work too.
No, you can use grey or walls that are just off white but you dont want strong colours really. You can get away with a bit more than you might think and the others walls dont have to be dark. Experiment as much as you can, just use yourself as subject and put the camera on a tripod.
Top tip: carry a white plastic shower curtain, foil emergency blanket and a roll of tape in your bag in case there are only dark walls, or some weird colour cast. Got me out of a few tricky situations! You can also use as a diffuser for sunlight, a flag, or sit on it if it's wet.
Wouldn't a reflector and stnd be easier to carry?
In addition, your portrait skills are just oustanding thank you Martin. The lighting and the tones are all about skill. Thanks for letting me rant.
Thank you so much !
The inverse square law follows from the geometry. Imagine you have a lightbulb that sends out light in all directions. Now imagine a sphere at a distance 1 meter, and another sphere at a distance of 2 meters. The surface area of the sphere at 2 meters distance is four times as large (remember 4*pi*r^2 is the area) as the sphere at 1 meter distance. The same light that touched the "1 meter sphere" now is spread out over four times as large an area of the "2 meter sphere", which means that the light intensity is one quarter. At a distance of 4 meters, the light now has 1/16 the intensity because the area of the "4 meter sphere" is 16 times larger than it was at the first "1 meter sphere".
Hooray for Team Physics! As one gets further away, the drop off becomes linear - every 1% increase in distance leads to a ~2% drop in light. So whereas going from 10m to 20m drops the light by 75%, going from 100m to 110m, 10% further away, drops it by 20% (21% for the pedants). Thank you Gauss and Newton!
Your videos are always informative and the information is presented in a clear and concise manner. Some of the best out there - thank you.
You are a great teacher.
The best explanation and demystifying of flash that I have come across. Thankyou.
Be great to see a demonstration of using this technique
Your videos are so helpful for people who love photography, and are not just obsessed with the latest gear. Thank you.
Martin, great presentation. I couldn't agree more, lots of people just don't get it. You have covered part of the subject very well. Thanks again.
Love your editing style….beautiful tones and lighting
Martin, these videos and your presentation are great! Your videos on the 5D and 6D inspired me to buy a used 5D mkii and I love it. This video as well, it is remembering the basics of light and capture. Thanks.
Just what I needed as doing my first wedding gig this week. Thanks for explaining this so well, love your approach no snobbery or nonsense. Will be working my way through all your videos.
Thank you Martin!
Love your photos
I'M NOT ONE TO LOOK AND LEARN HOW ANOTHER EDITS...BUT I LOVE YOUR WORK...SO I WILL HAVE TO CHECK OUT YOUR VIDEO YOU MENTIONED!!💯💯💯
Very good thank you.
Welcome!
Now I understand a fair bit about light fall off, consistency and how you process to get the softer look.. thanks as always Martin!
Re the Inverse square law.
The math behind it is based of a point light source but you can apply the theory to diffused and other light sources.
For the inverse square law as you double the light source to subject distance the intensity of that light reduces by 75% or to 1/4 of what it was at source. In photography terms you lose 2 stops.
You have 2 subject in a photograph / portrait the person in the frame and the background, the closer you have your light source the faster the fall off of light will be and darker the background will become, the further away the more gradual it will be and the lighter the background will be, it's all about distance.
Trying to light a large group of people you need to work the light further away so the exposure is even or more even across the group. Want it to be soft, you will need modifier that makes the light larger relative to your subject and you will need more flash power.
The best way to get to grips with it is to shoot example images, we work in a visual art from after all.
nice explaination!
@@MartinCastein Thank you.
I think you really have a unique style. A lot of portrait photographers have very similar looks to their pictures. But you, I don't know if it's the lighting or the editing, but I think I could recognize your work right away every time.
Love those shots Martin. Thanks for explaining how to light in a confined space 👍
Flash videos! Yes! Not sure why I struggle with flash settings but it all seems quite complicated. I’ve purchased 2 canon flash heads and have never used either one. I really gotta spend some time sorting it out.
Really useful, thank you Martin. Knowing very little about interior portrait photography, I assumed that you used complex and expensive pro setups to get such a nuanced lighting effect...
Glad it was helpful!
Just discovered your TH-cam channel a couple of days ago. I have to say your portraits have the most amazing look to them; really beautiful. Subscribed.
Nice light stand! I recently purchased 2 light stands to go with my setup but alas, they are heavy and quite a pain to take on the bus/subway. That Manfroto would go right on to my backpack on the other side of my tripod and life would be easier.
This is exactly the type of video I've been looking for... For about a year. FINALLY. THANK YOU! ❤🤠 📸
Two things. 1. Please show us HOW you shoot in a tiny room with one speed light. 2. Please show us HOW to edit on free software (ex. Canon, Nikon) without using Abode subscription apps.
That’s coming later on 🙂
Would it be wise to have either one wall (the bounce) painted white and the rest darker/black for more control or all white, im setting up a little 'studio' and like the idea of the bounce.
white would be better yes but grey works too, black will make life hard obviously as it wont reflect as well.
@MartinCastein thanks, I'll try out both and see what works best for the space 👍 I'll hold off on the black paint.
A wonderful explanation. Do you adjust the zoom on the flash such as making it 24mm or 85mm or do you leave it in one setting?
i do if the the bounce surface is further away or i make it wider if its closer.
Great content Martin. I like how these photos are edited and I consider your ws. Could be a nice edit also for a child’s portrait I think.
Good explanation. I have a lot of lenses, but no flash. I think I should add one. I like taking portraits at sunset, and I think it will help get the effect I want. Those pictures you showcased here are amazing!
Good video. Cheers.
Great explanation and very practical. I've bounced speedlights against back walls on many shoots. Here's a physics and light question: When the light hits the back wall and bounces back, doesn't the back wall become the new source of light and a new light falloff calculation begins there, at its new 'source' relative to the subject? Or, is the distance from the flashhead to the back wall and then to the subject, the total distance of the light falloff calculation? Lastly, how would you handle it if the walls were painted a strong color? In the name of simplicity, would you go umbrella or softbox?
Hi Bob, as far as I know the rate at which light reduces starts from the point of origin, inverse square law as i understand it covers the spreading of light and the rate of reduction. so the spreading part would start again i suspect from the wall but the rate of reduction starts from the place the light first came out of. IF the walls are painted you could use an umbrella or softbox if the space is big enough but they would have to be 6 or 7 foot to get the same look. You could if you want to save money hang a white bed sheet even on the wall. you could hang a white sheet as a modifier as well, so somethign like umbrella to avoid hot spot then hang a large bed sheet to diffuse the light. that would work too.
😊thanks...I needed this
Great info! Martin, what sort of trigger are you using? Could you recomment something for a canon 6d mrk 1?
I used the pocket wizard plus ii I think that’s probably quite old now though
Hi Martin!
Does it require to have a white wall (witch is the one in flash direction) and the others have to be dark?
No, you can use grey or walls that are just off white but you dont want strong colours really. You can get away with a bit more than you might think and the others walls dont have to be dark. Experiment as much as you can, just use yourself as subject and put the camera on a tripod.
@@MartinCastein Thank you Martin
👍👍👍
Wel explained.....SUB from me. ❤
I really do need to learn how to use flash. I have never used flash but have inherited some along with my camera and lens. Thanks @martincastein