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Archive 2009DIY Macro Diffuser
p.1 #1DIY Macro Diffuser
I've decided to give macro a try so I bought a set of Kenko tubes and made a diffuser similar in concept to the approach I use with dual 580ex flash with regular subjects. My take on lighting is that you'd light a flea or elephant the same way with frontal fill to reveal detail and a directional key light to define the 3D shape. So here's what I've devised for my 580ex as an alternative to buying a macro flash.
http://super.nova.org/Macro/MacroDIY_DiffuserFront.jpg
http://super.nova.org/Macro/MacroDIY_DiffuserBack.jpg
The flash in the background is equipped with the DIY diffuser I use for regular subjects...
http://super.nova.org/TP/DIYdiffusers.jpg
Here are some test shots taken with all the Kenko tubes and my 85mm f/1.8 at F/11 - 13. Overall I'm pleased with the results I'm getting using just one flash or with two. When shooting with one I found it necessary to dial in about - 2/3 FEC. When I flipped the switch to Master and went to dual flash, using the second flash behind as rim light, I had to raise FEC to +2/3
Single flash:
http://super.nova.org/Macro/MacroDIY_OneFlash.jpg
Dual Flash:
http://super.nova.org/Macro/MacroDIY_DualFlash.jpg
Single Flash:
http://super.nova.org/Macro/MacroDIY_Single_Berry.jpg
Dual Flash:
http://super.nova.org/Macro/MacroDIY_Dual_Berry.jpg
Other single flash shots:
http://super.nova.org/Macro/MacroDIY_Single_Lens.jpg
http://super.nova.org/Macro/MacroDIY_Single_Keys.jpg
http://super.nova.org/Macro/MacroDIY_OneFlash_Phone.jpg
Dual flash:
http://super.nova.org/Macro/MacroDIY_Dual_Flower.jpg
http://super.nova.org/Macro/MacroDIY_Dual_Leaf.jpg
The rig on the camera is very light and after a making one prototype I was able to refine the design to two pieces which fold flat - its held together with velcro.
Chuck
http://super.nova.org/Macro/MacroDIY_DiffuserFront.jpg
http://super.nova.org/Macro/MacroDIY_DiffuserBack.jpg
The flash in the background is equipped with the DIY diffuser I use for regular subjects...
http://super.nova.org/TP/DIYdiffusers.jpg
Here are some test shots taken with all the Kenko tubes and my 85mm f/1.8 at F/11 - 13. Overall I'm pleased with the results I'm getting using just one flash or with two. When shooting with one I found it necessary to dial in about - 2/3 FEC. When I flipped the switch to Master and went to dual flash, using the second flash behind as rim light, I had to raise FEC to +2/3
Single flash:
http://super.nova.org/Macro/MacroDIY_OneFlash.jpg
Dual Flash:
http://super.nova.org/Macro/MacroDIY_DualFlash.jpg
Single Flash:
http://super.nova.org/Macro/MacroDIY_Single_Berry.jpg
Dual Flash:
http://super.nova.org/Macro/MacroDIY_Dual_Berry.jpg
Other single flash shots:
http://super.nova.org/Macro/MacroDIY_Single_Lens.jpg
http://super.nova.org/Macro/MacroDIY_Single_Keys.jpg
http://super.nova.org/Macro/MacroDIY_OneFlash_Phone.jpg
Dual flash:
http://super.nova.org/Macro/MacroDIY_Dual_Flower.jpg
http://super.nova.org/Macro/MacroDIY_Dual_Leaf.jpg
The rig on the camera is very light and after a making one prototype I was able to refine the design to two pieces which fold flat - its held together with velcro.
Chuck
Dec 17, 2009 at 02:23 PM
p.1 #2DIY Macro Diffuser
Ain't DIY fun?! For me, it seems to be much more fun designing and building something than going out and buying it.
Light looks very good, Chuck. I've read a lot of your posts in other forums here and tend to share your assessment of lighting. All that said, however, I'd have a problem working a diffuser that size into some of the spots I shoot active critters.
Kenny
Light looks very good, Chuck. I've read a lot of your posts in other forums here and tend to share your assessment of lighting. All that said, however, I'd have a problem working a diffuser that size into some of the spots I shoot active critters.
Kenny
Dec 17, 2009 at 02:49 PM
p.1 #3DIY Macro Diffuser
Light setup working well for studio type shots !
Brian v.
Brian v.
Dec 18, 2009 at 12:59 AM
p.1 #4DIY Macro Diffuser
I like the color of the light that your getting, but I think that the diffusion could be better (the specular highlights look a little harsh to me). Do you have some sort of diffuser on your camera mounted flash, or just what I can see in the photo? It looks more like a barn door / shoot than a diffuser.
Dec 19, 2009 at 06:04 AM
p.1 #5DIY Macro Diffuser
R.H.Jonhson,
Is that a 'Fong light sphere' that you have pictured there, or some master to student super secret project handed down?
Bruce
Dec 23, 2009 at 04:03 AM
p.1 #6DIY Macro Diffuser
R.H.Jonhson,
Is that a 'Fong light sphere' that you have pictured there, or some master to student super secret project handed down?
Bruce
Dec 23, 2009 at 04:03 AM
p.1 #7DIY Macro Diffuser
R.H.Jonhson,
Is that a 'Fong light sphere' that you have pictured there, or some master to student super secret project handed down?
Bruce
Dec 23, 2009 at 04:01 AM
p.1 #8DIY Macro Diffuser
Thanks to all for the feedback. I don't think the size will be an impediment. I don't plan on crawling on my belly chasing bugs at 10x and the diffuser isn't any longer than the tubes or lenses I'll likely use. I'm more inclined towards longer lenses with 1' + MFD: 100mm Canon or the 150mm Sigma...
R.H.: I've tried similar DIY devices in the past...
http://super.nova.org/TP/RMDiffuser.jpg
The problem I see with that approach with a single flash is a lack of fill.
The basic dilemma of the photographic process is color / digital is that even a flat-lit scene will usually exceed the range of the sensor. When that's the case exposing for the highlight detail results in a loss of shadow detail. The solution is to use two flashes in an overlapping pattern of key over even fill light.
Having cut my photographic teeth in B&W withe the zone system I learned how to put detial over the entire tonal range with just the ambient light. That's possible becuase the contrast of the negative can be altered to match the scene range and fit it to the fixed range of the print paper. Shooting weddings with dual flash taught me to do the same thing by first lifting the shadows illuminated with whatever ambient light the camera can record with one flash, then overlap a second as "key" light to created the highlights over the fill. Ideally Fill should be even and shadowless because anytime the fill casts a shadow there is a dark unfilled void in the lighting pattern.
In creating the diffuser my first goal was to create an even source of light from the camera axis. But something else I've learn about lighting is the affect its direction has on the perception of what looks "normal" and "natural". In person we rely on stereo vision, shifting narrow focus, and parallax (how the foreground / background relationship changes as we move our heads) to get clues about depth and object shape. In a photo we rely entirely on different forms of contrast to create the same illusion: contrasting tone, color, sharpness, shape, etc. When looking at a photo we see the pattern of tonal contrast and the brain matches it to memories of seeing similar objects in the same light.
Where the direction of light comes into play is the fact that most outdoor and indoor light comes from overhead most of the time. Outdoors there is one light source - the sun - but two light directions: the direct rays of the sun, and the "fill" light reflected from the sky. Both create a downward modeling pattern on faces and other objects. When a photo is illuminated with light from that same direction - above the subject - it will wind up seeming more naturally modeled in a photo.
If you look at the close-up of the Santa head and phone key pad shot with just the diffuser on the camera you will notice a natural downward shadow pattern resulting from the fact the light source sits on top of the lenshood rather than coming from the sides as with a ring light. The modeling on the Santa figure is nearly identical to the modeling on a real human face when a single flash is raised over head on a bracket. So I was quite pleased with the results because they look "natural".
When a second flash is added for back-rim light the natural angle of the frontal lighting is retained much in the same way as outdoors in natual light when the subject's back is placed to the sun. In human portraiture one the the things photographers don't seem to notice is how when the subject is in open shade or backlight the brow still will shade the eyes making them darker. In backlight outdoors the roles of the sources change: the sun becomes what is conventionally called an "accent" or "hair" light and the open sky becomes the "KEY" light source on the front of the face or object. Like the sun it comes from overhead creating a downward pattern, but often so high the brow shades it. Conventional wisdow says add fill to open up the dark eyes but lack of fill isn't the problem. The dark eyes are caused by a lack of KEY LIGHT IN THE EYES. The solution? Raise the chin into the light so it reaches the eyes
Bugs and most other critters don't have recessed eye sockets so dark sockets aren't a problem but the "fill" light will still provide more natural looking clues to shape if it comes from overhead. The only reason the "Key" light is put in front of the face for humans is the need to get light into the eyes for good "eye contact" and to model the shape of the nose sticking out between them. In general a much stronger impression of 3D shape in a photo is created with back-side lighting:
http://super.nova.org/TP/Egg.jpg
That shot was done to demonstrate how to shoot a materity portait without the mother's belly looking like the Goodyear Blimp. Rim light the object and then shoot into the shadows, revealing the detail on the shadow side with the fill source.
That gets us back to the role of fill. Photographers refer to light as being "hard" or "soft" without really understanding the perceptual cause and effect. In a photo the strongest clues for the impression of hard and soft come from the tone of the shadows. The darker and less detailed the shadows, the harder the light seems. Open the shadows with adequate even fill from a natural downward direction and the same object will seem softer and rounder. I learned that shooting weddings back in the 1970s for Monte Zucker. He introduced the idea of using dual flash to wedding coverage using one on a bracket and the other on a wheeled stand triggered by an optical slave. We used direct flash, no diffusion, and controlled the illusion of softness with the lighting ratio: 2:1, 3:1, 4:1, etc. The lower the ratio the lighter the shadows and the softer and rounder the object illuminated seems.
Conventional wisdom today seems to be to use large key light diffusers close to the subject to wrap the light around the object. Diffusion is affected by source size and distance, but the actual cause and effect is that the large source used close makes the light direct less parallel relative to the object. Move the source further away and the light becomes more parallel and the shadows more distinct. Its a valid approach - there are no rules - but one which offers no independent control over the shadows. It also creates two-tone shadows: umbra (the dark core of the shadow) and penumbra (the feathered edge created by the wrap effect.
Creating fill from near the camera axis with an independently contolled source works by first lifting all the shadows to the level the lame, short range camera sensor can record detail...
http://super.nova.org/TP/LE01.jpg
Back in the Zone System days we'd use a spot meter to set exposure to the darkest shadow we wanted to carry detail but with digital its possible to do it visually from the playback and histogram. The beauty of the "neutral" fill appoach is how it makes the rest of the process of exposure a no-brainer on a digital camera. With even fill as the foundation for everything the camera sees all the other lights will overlap it. So determining correct exposure and fitting the scene to the range of the sensor exactly is simply a matter of raising the intensity of the other key and accent lights until the point just below clipping is reached. Again the instant feedback of digital and its over-exposure "idiot light" display are a big part of making it simple.
http://super.nova.org/TP/LE04.jpg
When I add the second flash to the macro diffuser on the camera I want it behind the object about 135 degrees from the lens axis and above, with the frontal lighting coming from just above the lens axis. There are two lights, but three light sources:
1) Accent light from the off camera flash
2) Directional downward "key" light from the diffuser on the camera.
3) Ambient fill in all the areas the two flashes don't reach
As mentioned the results I'm seeing on the small objects is very similar to what I get with larger ones with the Master Fill on bracket, off camera key light so I'm pleased with the results and the feedback I've received. I'm convinced I don't have a compelling need to buy a MR-14 or MR-24 or macro bracket for what I want to do, which means I can rationalize buying that macro lens sooner
Chuck
R.H.: I've tried similar DIY devices in the past...
http://super.nova.org/TP/RMDiffuser.jpg
The problem I see with that approach with a single flash is a lack of fill.
The basic dilemma of the photographic process is color / digital is that even a flat-lit scene will usually exceed the range of the sensor. When that's the case exposing for the highlight detail results in a loss of shadow detail. The solution is to use two flashes in an overlapping pattern of key over even fill light.
Having cut my photographic teeth in B&W withe the zone system I learned how to put detial over the entire tonal range with just the ambient light. That's possible becuase the contrast of the negative can be altered to match the scene range and fit it to the fixed range of the print paper. Shooting weddings with dual flash taught me to do the same thing by first lifting the shadows illuminated with whatever ambient light the camera can record with one flash, then overlap a second as "key" light to created the highlights over the fill. Ideally Fill should be even and shadowless because anytime the fill casts a shadow there is a dark unfilled void in the lighting pattern.
In creating the diffuser my first goal was to create an even source of light from the camera axis. But something else I've learn about lighting is the affect its direction has on the perception of what looks "normal" and "natural". In person we rely on stereo vision, shifting narrow focus, and parallax (how the foreground / background relationship changes as we move our heads) to get clues about depth and object shape. In a photo we rely entirely on different forms of contrast to create the same illusion: contrasting tone, color, sharpness, shape, etc. When looking at a photo we see the pattern of tonal contrast and the brain matches it to memories of seeing similar objects in the same light.
Where the direction of light comes into play is the fact that most outdoor and indoor light comes from overhead most of the time. Outdoors there is one light source - the sun - but two light directions: the direct rays of the sun, and the "fill" light reflected from the sky. Both create a downward modeling pattern on faces and other objects. When a photo is illuminated with light from that same direction - above the subject - it will wind up seeming more naturally modeled in a photo.
If you look at the close-up of the Santa head and phone key pad shot with just the diffuser on the camera you will notice a natural downward shadow pattern resulting from the fact the light source sits on top of the lenshood rather than coming from the sides as with a ring light. The modeling on the Santa figure is nearly identical to the modeling on a real human face when a single flash is raised over head on a bracket. So I was quite pleased with the results because they look "natural".
When a second flash is added for back-rim light the natural angle of the frontal lighting is retained much in the same way as outdoors in natual light when the subject's back is placed to the sun. In human portraiture one the the things photographers don't seem to notice is how when the subject is in open shade or backlight the brow still will shade the eyes making them darker. In backlight outdoors the roles of the sources change: the sun becomes what is conventionally called an "accent" or "hair" light and the open sky becomes the "KEY" light source on the front of the face or object. Like the sun it comes from overhead creating a downward pattern, but often so high the brow shades it. Conventional wisdow says add fill to open up the dark eyes but lack of fill isn't the problem. The dark eyes are caused by a lack of KEY LIGHT IN THE EYES. The solution? Raise the chin into the light so it reaches the eyes
Bugs and most other critters don't have recessed eye sockets so dark sockets aren't a problem but the "fill" light will still provide more natural looking clues to shape if it comes from overhead. The only reason the "Key" light is put in front of the face for humans is the need to get light into the eyes for good "eye contact" and to model the shape of the nose sticking out between them. In general a much stronger impression of 3D shape in a photo is created with back-side lighting:
http://super.nova.org/TP/Egg.jpg
That shot was done to demonstrate how to shoot a materity portait without the mother's belly looking like the Goodyear Blimp. Rim light the object and then shoot into the shadows, revealing the detail on the shadow side with the fill source.
That gets us back to the role of fill. Photographers refer to light as being "hard" or "soft" without really understanding the perceptual cause and effect. In a photo the strongest clues for the impression of hard and soft come from the tone of the shadows. The darker and less detailed the shadows, the harder the light seems. Open the shadows with adequate even fill from a natural downward direction and the same object will seem softer and rounder. I learned that shooting weddings back in the 1970s for Monte Zucker. He introduced the idea of using dual flash to wedding coverage using one on a bracket and the other on a wheeled stand triggered by an optical slave. We used direct flash, no diffusion, and controlled the illusion of softness with the lighting ratio: 2:1, 3:1, 4:1, etc. The lower the ratio the lighter the shadows and the softer and rounder the object illuminated seems.
Conventional wisdom today seems to be to use large key light diffusers close to the subject to wrap the light around the object. Diffusion is affected by source size and distance, but the actual cause and effect is that the large source used close makes the light direct less parallel relative to the object. Move the source further away and the light becomes more parallel and the shadows more distinct. Its a valid approach - there are no rules - but one which offers no independent control over the shadows. It also creates two-tone shadows: umbra (the dark core of the shadow) and penumbra (the feathered edge created by the wrap effect.
Creating fill from near the camera axis with an independently contolled source works by first lifting all the shadows to the level the lame, short range camera sensor can record detail...
http://super.nova.org/TP/LE01.jpg
Back in the Zone System days we'd use a spot meter to set exposure to the darkest shadow we wanted to carry detail but with digital its possible to do it visually from the playback and histogram. The beauty of the "neutral" fill appoach is how it makes the rest of the process of exposure a no-brainer on a digital camera. With even fill as the foundation for everything the camera sees all the other lights will overlap it. So determining correct exposure and fitting the scene to the range of the sensor exactly is simply a matter of raising the intensity of the other key and accent lights until the point just below clipping is reached. Again the instant feedback of digital and its over-exposure "idiot light" display are a big part of making it simple.
http://super.nova.org/TP/LE04.jpg
When I add the second flash to the macro diffuser on the camera I want it behind the object about 135 degrees from the lens axis and above, with the frontal lighting coming from just above the lens axis. There are two lights, but three light sources:
1) Accent light from the off camera flash
2) Directional downward "key" light from the diffuser on the camera.
3) Ambient fill in all the areas the two flashes don't reach
As mentioned the results I'm seeing on the small objects is very similar to what I get with larger ones with the Master Fill on bracket, off camera key light so I'm pleased with the results and the feedback I've received. I'm convinced I don't have a compelling need to buy a MR-14 or MR-24 or macro bracket for what I want to do, which means I can rationalize buying that macro lens sooner
Chuck
Dec 23, 2009 at 07:02 AM