Overpower the Sun? Misnomer? Or Fact

[MDJAK]

So, I keep reading posts wherein people with 400ws strobes, etc., need that type of power in order to overpower the sun.

Sounds a bit fishy to me, but I know I'm a dope.

How exactly on a bright sunny day does one set one's camera and strobes so the sun's light plays no role either in exposure or in lighting the subject?

And what exactly does it mean to overpower the sun? Is that something that is fantasy, an expression, or is it actually accomplished? How?

Before and after pictures would be very helpful in understanding this often referred to topic.

Thank you in advance.


mark

[TMR Design]

So, I keep reading posts wherein people with 400ws strobes, etc., need that type of power in order to overpower the sun.

Sounds a bit fishy to me, but I know I'm a dope.

How exactly on a bright sunny day does one set one's camera and strobes so the sun's light plays no role either in exposure or in lighting the subject?

And what exactly does it mean to overpower the sun? Is that something that is fantasy, an expression, or is it actually accomplished? How?

Before and after pictures would be very helpful in understanding this often referred to topic.

Thank you in advance.


mark


Hey Mark,

Here is an example that may make it easier to understand. Let's say you're outside in midday Sun and you determine that the ambient exposure is f/16. If you were to shoot your subject at f/16 you'd get a bright background and more than likely find it distracting and perhaps have a blown out sky or clipped highlights in other parts of the frame.

Typically, we try to underexpose the background by 1, 2 or 3 stops. For this example, lets say you want to underexpose by 2 stops. This means that if the background is going to be 2 stops under the subject exposure that you need the firepower to expose the subject at f/32. Let's also say that the f/32 has to be at a distance of about 6 feet firing into a 60" octa. That's not something that Speedlight's or small strobes can deliver. So, it means you need more power to be able to kick out that amount of light. If you wanted to underexpose the background by 3 stops on a very bright day then that would mean you need to be able to fire at f/45. That extra stop is going to require a powerful strobe.

There are other technical aspects of this and of course you would need an ND filter to reduce the overall amount of light reaching the sensor so that you can shoot at a larger aperture but that example outlines the concept of what we mean by overpowering the Sun and why we need to do it.

Photographers will also use scrims and diffusion panels to tame the Sun and get the numbers back to normal but either way the concept remains the same. This is why many people choose to shoot in the shade or in morning or afternoon light when the Sun isn't directly overhead and you don't have to combat the Sun.

[ErikatSSI]

If you have a fast enough sync speed it is not as hard as it sounds. It will have to be much faster than the 1/200 most cameras alone are capable of though. the new PWs come to mind as they can increase flash speed by anticipating the shutter opening and starting the flash's firing sequence earlier. Or you can get really large flashes and just crank up the juice.


Erik

[Ainoko]

What you have to consider here is that the sun is a continuous light source, whereas a strobe produces a flash lasting about 1/4000th of a second or so. Strobes are capable of putting out plenty of light too, but over a much shorter amount of time. Therefore, when you speed up your shutter, you are knocking down the length of time your sensor is exposed to the sun. This is not the case with strobes (that is, anything slower than the speed of the flash, in this case 1/4000th of a second). Therefore if you mix sunlight with strobe light, adjusting only the shutter speed effects only the light from the sun. Say you are shooting midday, f16 @iso100 1/125th. You put your subject in front of you, and set your strobe to properly expose them at f16 iso100. So both the ambient light from the sun, and your subject (lit by the strobe) are being properly exposed. Now, if you drop the shutter speed to 1/250th, you are knocking down the ambient light by one stop. However, since the strobe is unaffected by the change in shutter speed, the subject remains properly exposed while your ambient is now one stop darker. Now, if you want the ambient light to be even darker, you could change your shutter speed to 1/500th of a second. This would knock down the ambient further, and still leave the strobe's light unaffected. The problem now is that most cameras' max sync speed is only 1/250th, and therefore this would not be possible. This is where strobe power comes into play. Say you are at half power on your strobe. You could now increase the power to full, which would cause your subject to be overexposed by one stop of light. Now you can close your aperture by one stop to f22 to compensate in order to get a proper exposure on your subject. However, aperture also affects the ambient light of the sun, and would also drop the sunlight by one stop as well. At this point you have dropped the ambient light of the sun below that of your strobe, and have "Overpowered the sun" (in a sense). The problem now is that if you want to drop the ambient ANOTHER stop, how are you going to achieve that? Your shutter speed is already maxed at 1/250th, and your strobe is at full power. This is where it is becomes important to have a higher powered strobe. (You could, of course, also move your strobe in closer, but again you can only move it in so far, and distance also affects quality).

Hope this helps!

[TMR Design]

OK lets be clear about something. Before we had Speedlight's with HSS or FP modes you could only work as fast as the max sync speed of the camera. With strobes and triggers the max sync speed in many cases isn't even as fast as the max sync speed. That spec is based on using a branded TTL Speedlight, not strobes.

So if we're talking about studio strobes, which is still what most pros shoot with on location it can only be done with more power.

If you're talking about Speedlights then there are limitations with HSS and FP modes when working with a large modifier at a distance. Those modes work great with close lighting but at a distance you're still going to run into problems.

The new Hypersync modes with strobes can only go so far as well. Some strobes allow for higher sync speeds than others so in some cases you may be able to get the extra 1, 2 or 3 stops.

[alduin]

You can do it with speedlites if you've got an in with Canon and RadioPopper/PocketWizard...

http://pixsylated.com/2008/12/i-shot-ben-willmore-in-broad-daylight-gang-light-part-1/

[TMR Design]

You can do it with speedlites if you've got an in with Canon and RadioPopper/PocketWizard...

http://pixsylated.com/2008/12/i-shot-ben-willmore-in-broad-daylight-gang-light-part-1/

Well, that's a bit extreme but regardless it's still making a case for more power. Using 12 Speedlight's is not within the realm of what most people can do or want to do.

[RPCrowe]

If you have a fast enough sync speed it is not as hard as it sounds. It will have to be much faster than the 1/200 most cameras alone are capable of though. the new PWs come to mind as they can increase flash speed by anticipating the shutter opening and starting the flash's firing sequence earlier. Or you can get really large flashes and just crank up the juice.


Erik

That is a reason that High Speed Sync is handy. HSS allows you to use a higher shutter speed but, is not available on studio strobes - only on selected hotshoe flashes made by Canon and Sigma.

[mikekelley]

I'd call it taming the sun, and controlling it, not overpowering it ;)

[ErikatSSI]

Yes but the new PW units don't use HSS like the radio poppers do, they apparently jump the flash timing all together, so instead of many weaker pulses you get a real full strength flash pulse in time at up to 1/500 sync speed. so not only do you get more output from the flashes, you can also keep out that much more of the ambient light.



Note- I do not have these PWs yet but have watched another photographer use them and all I could say was WOW. not enough to make my AB800s useless but quite impressive for a pair of 580exIIs non the less. Especially considering the mobility advantage of that kind of light from a 2 relatively small hot shoe flashes. Hopefully someone here has a set and can shed some more light on how well they work.


Erik

[Wilt]

That is a reason that High Speed Sync is handy. HSS allows you to use a higher shutter speed but, is not available on studio strobes - only on selected hotshoe flashes made by Canon and Sigma.


But for every two EV faster shutter speed, the effective range of HSS is cut by HALF. So at 1/250 if you have a 580EXII which could reach at f/8 out to 16' (GN130 at 50mm coverage angle), at 1/1000 the same f/8 could only reach to 8' (GN65 at 1/1000) This is the result of spreading the output of the HSS speedlight over a longer duration of time.

[FlyingPhotog]

Isn't it really just balancing artificial frontlight Vs natural backlight?

I don't think I've ever seen a mid-day, full-sun shot where the artificial light completely killed all the ambient.

[strmrdr]

Isn't it really just balancing artificial frontlight Vs natural backlight?


basically yes.

Your main light needs to be stronger than your background light which is the sun.
It is no different than setting ratios in the studio.
The main light needs to be stronger than the other lighting to separate your subject from the background.
That is unless you want to blow out the background which you sometimes do.

[MDJAK]

Thank you everyone. I do appreciate the time people here take to help out. It's what makes this forum special.

I think I'm beginning to understand now. So, it's really about being able to underexpose the background so it doesn't appear to be so bright and contrasty, yet lighting the model the way you want with the lights. Yes?

As an aside, and I'll post an example, I shot some family portraits for thanksgiving last evening. Unfortunately, the sun went down so quickly that I was faced with shooting basically in the dark. I only had 3 of my 4 speedlights. One on camera in master, two remote shooting from the side. I had to shoot at around 1/30 at f2.8 ISO 2000 or above in order to get proper exposure. The results sucked once I looked at them at 100 percent. Very disappointing. Grainy with lots of noise.

What if anything could I have done differently other than done it earlier in the day?

Here's an example:http://www.pbase.com/mdjak/image/119760095/original.jpg

That was before it got totally dark.

[MDJAK]

by this time, the sun had fully set:
http://www.pbase.com/mdjak/image/119760109.jpg

I wanted to shoot at a much lower ISO, but the pics were coming out too dark.

What else could I have done?

Thanks again.
mark

[Austin.Manny]

Hey Mark,

Here is an example that may make it easier to understand. Let's say you're outside in midday Sun and you determine that the ambient exposure is f/16. If you were to shoot your subject at f/16 you'd get a bright background and more than likely find it distracting and perhaps have a blown out sky or clipped highlights in other parts of the frame.

Typically, we try to underexpose the background by 1, 2 or 3 stops. For this example, lets say you want to underexpose by 2 stops. This means that if the background is going to be 2 stops under the subject exposure that you need the firepower to expose the subject at f/32. Let's also say that the f/32 has to be at a distance of about 6 feet firing into a 60" octa. That's not something that Speedlight's or small strobes can deliver. So, it means you need more power to be able to kick out that amount of light. If you wanted to underexpose the background by 3 stops on a very bright day then that would mean you need to be able to fire at f/45. That extra stop is going to require a powerful strobe.

There are other technical aspects of this and of course you would need an ND filter to reduce the overall amount of light reaching the sensor so that you can shoot at a larger aperture but that example outlines the concept of what we mean by overpowering the Sun and why we need to do it.

Photographers will also use scrims and diffusion panels to tame the Sun and get the numbers back to normal but either way the concept remains the same. This is why many people choose to shoot in the shade or in morning or afternoon light when the Sun isn't directly overhead and you don't have to combat the Sun.

Actually, f-stops are in intervals of x1.4, not x2; so 2 stops below f/16 would be around f/32. ;)

[bobbyz]

Shoot earlier in the evening.

[TMR Design]

Actually, f-stops are in intervals of x1.4, not x2; so 2 stops below f/16 would be around f/32. ;)

I know how f-stops work and never made mention of a factor of 2. Why are you attempting to correct me with the same information I've presented. I stated that 2 stops under f/16 is f/32. You said the same thing except you added the word 'around'. 2 stops below f/16 is exactly f/32.

[bobbyz]

I know how f-stops work and never made mention of a factor of 2. Why are you attempting to correct me with the same information I've presented. I stated that 2 stops under f/16 is f/32. You said the same thing except you added the word 'around'. 2 stops below f/16 is exactly f/32.

Rookie trying to teach f-stop math to Robert.:D

Happy Thanksgiving BTW.

[pridash]

by this time, the sun had fully set:
http://www.pbase.com/mdjak/image/119760109.jpg

I wanted to shoot at a much lower ISO, but the pics were coming out too dark.

What else could I have done?

Thanks again.
mark

Shooting in that low light, makes your off camera work pretty much like straight on flash.

The only way to have made that photo more interesting was to use your other flashes to light up the background...perhaps pointing at the trees. This is assuming off course you had enough power to also light up your main subjects.

[Curtis N]

Mark,
Here are the concepts involved:
1) Yes, it is possible to overpower the sun
2) Shutter speed is one key, and it is advantageous to have a camera with a fast X-sync speed
3) High Speed Sync does not help. It makes things worse.
4) The amount of flash power required varies exponentially with the distance from flash to subject.

These shots should help tell the story.
First, you reduce the ambient exposure by closing the aperture.

http://performancephoto.smugmug.com/photos/725149748_BFFtj-L.jpg

http://performancephoto.smugmug.com/photos/725149752_XM52P-L.jpg

http://performancephoto.smugmug.com/photos/725149766_VAZ8U-L.jpg

Then, you add the flash. In the image below, the subject is illuminated but not the background. I have overpowered the sun.

http://performancephoto.smugmug.com/photos/725149756_XQzLd-L.jpg

High speed sync effectively reduces your flash power. For this last shot, I went to 1/500 f/16 (the same ambient exposure as the shot above). With the flash in HSS mode, it didn't have enough power for proper illumination.

http://performancephoto.smugmug.com/photos/725149751_JGAsY-L.jpg

As you can see, even a diffused 580EX II can overpower the sun, if the distance is close enough. As you move the light further away for larger subjects, you will need exponentially more power. This is why people use studio strobes for this kind of effect in sunny conditions.

[J Kacey]

Are we talking about overpowering the sun or overpowering the ambient?
http://kacey.smugmug.com/photos/311927010_4TeoD-M.jpg

[TMR Design]

Are we talking about overpowering the sun or overpowering the ambient?
http://kacey.smugmug.com/photos/311927010_4TeoD-M.jpg

Since the Sun was originally mentioned I think that's what we're talking about. Obviously there can be many scenarios with ambient light that don't involve direct or overhead Sun but either way the concept is the same. Obviously overpowering the ambient from direct Sun light is more difficult that ambient on a cloudy day or in the shade or indoors.

[FlyingPhotog]

New to the technique here but it can indeed work...
http://jcbeckman.zenfolio.com/img/v5/p263991047-4.jpg

[Ainoko]

Mark,
Here are the concepts involved:
1) Yes, it is possible to overpower the sun
2) Shutter speed is one key, and it is advantageous to have a camera with a fast X-sync speed
3) High Speed Sync does not help. It makes things worse.
4) The amount of flash power required varies exponentially with the distance from flash to subject.


How does high speed sync make things worse?

[CliveyBoy]

Ainoko, that statement does seem to need some clarification, and Curtis may yet provide it.

In terms of the OP - Overpower the Sun - HSS/FP Flash does make the position harder. The 550EX manual has a table of Guide Numbers that show the effect, eg at 24mm zoom:
1/250sec - 46'/14M
1/1000sec - 23'/7M
1/8000sec - 8'/2.5M

However, people like Tricoast use HSS in full daylight as part of their signature style. Part of it is to use f2.8 or so for a shallow DOF for portraits. That can readily be done with HSS.

So it is harder to use flash in HSS mode with backlight sun, but it is still possible and often dramatic. Battery packs are a must.

[int2str]

Single strobe on camera. HSS, 1/8000th shutter (!!), f/1.8, ISO 100:

http://lh3.ggpht.com/_uFrS5yCiGps/SgTEQHLmjbI/AAAAAAAAIUs/obpr5YEgZvU/s1024/IMG_1387.JPG

So it can be done with HSS and a single strobe. And yes, that was in very bright daylight with his back facing the sun.

[TMR Design]

Single strobe on camera. HSS, 1/8000th shutter (!!), f/1.8, ISO 100:

http://lh3.ggpht.com/_uFrS5yCiGps/SgTEQHLmjbI/AAAAAAAAIUs/obpr5YEgZvU/s1024/IMG_1387.JPG

So it can be done with HSS and a single strobe. And yes, that was in very bright daylight with his back facing the sun.

Yes, we know it can be done but your example is a closeup shot and not full length or a group. If yo had to pull back and needed the coverage a large modifier would offer then that's where the trouble begins.

Each of us that has posted indicating there would be a problem has mentioned it with regard to the size of the subject area and distance of light source to subject.

[Wilt]

Yes, we know it can be done but your example is a closeup shot and not full length or a group. If yo had to pull back and needed the coverage a large modifier would offer then that's where the trouble begins.

Each of us that has posted indicating there would be a problem has mentioned it with regard to the size of the subject area and distance of light source to subject.

^^^

int2str, re-read post #11 for how rapidly the max distance falls off. At the 1/8000 speed of your example, the max distance of your flash is a mere 1/6 of what it could reach at the max synch speed (1/250)