Help I want to overpower the sun

redmonkee

redmonkee

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Hi guys

is it possible to over the power the sun with a flash or strobe when using a wide aperture.

i know the common practice is to use a narrow aperture but I like shots with a buttery blurred background and just wondered how feasible this would be and also what kind of flash/strobe i'd need. I take it the big thing here would be the HSS capabilities of the flash:thinking:
 
If you could get fast enough a shutter to make it a flash only exposure then wouldn't the background be really dark?
 
To balance the sun, you need to get the flash close, not modify it, and use lots of power. Close up, a speedlight can sometimes do it, other times, it's just not big enough.

Once you've balanced with the sun, if you then want to claw back some shallow depth of field, you need to use ND filters and the lowest possible ISO so that you can open up again.

The lighting is all about the ratio between the light on the subject and the ambient from the sun, and the depth of field you then have to control in other ways, with the limitation of your shutter speed being as high as possible.

If you could get fast enough a shutter to make it a flash only exposure then wouldn't the background be really dark?
Click to expand...

yes but then you hit your max flash sync speed at 1/250th second (approx). Unless using a digital or leaf shutter that is, on cheap nikon Dslrs or the canon G11; or high end medium format cameras, respectively
 
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As above, for shallow depth of field and over powering the sun you're going to want a shed load of power and an ND filter on your lens
 
irelanst said:
If you could get fast enough a shutter to make it a flash only exposure then wouldn't the background be really dark?
Click to expand...

That would've been my answer. Highest possible shutter speed (using HSS as the OP said) and lowest possible ISO.

Never actually tried to completely overpower the sun. Not in a " day to night" sense anyway.
 
itsdavedotnet said:
To balance the sun, you need to get the flash close, not modify it, and use lots of power. Close up, a speedlight can sometimes do it, other times, it's just not big enough.

Once you've balanced with the sun, if you then want to claw back some shallow depth of field, you need to use ND filters and the lowest possible ISO so that you can open up again.

The lighting is all about the ratio between the light on the subject and the ambient from the sun, and the depth of field you then have to control in other ways, with the limitation of your shutter speed being as high as possible.



yes but then you hit your max flash sync speed at 1/250th second (approx). Unless using a digital or leaf shutter that is, on cheap nikon Dslrs or the canon G11; or high end medium format cameras, respectively
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Yup, basically that says it all

When overpowering the sun, you basically use the ambient lighting for the background and create your own light for the subject. Subtle lighting is often not needed in this situation, so you can maximise whatever power you have available by avoiding modifiers such as softboxes and umbrellas and by using highly efficient modifiers such as high intensity reflectors, beauty dishes etc.
 
It's really not difficult if you have HSS. I just dragged the Mrs out to garden and took a shot at ISO 100, 1/8000, f2.8. The flash has a Gn of 42.

The sky behind her isn't completely black but it's fairly close. Definitely mid-sunset level.
 
Johnd2000 said:
It's really not difficult if you have HSS. I just dragged the Mrs out to garden and took a shot at ISO 100, 1/8000, f2.8. The flash has a Gn of 42.

The sky behind her isn't completely black but it's fairly close. Definitely mid-sunset level.
Click to expand...

If that's a dSLR you're using, it's not straightforward HSS you're implementing, as the flashgun is actually"strobing" it's light at a reduced output. ok if you are pretty much nose to nose with your subject, but it soon loses it's intensity with any distance.

Edit:
Due to slow typing and distractions, [user]Triggaaar[/user] pretty said it, and beat me to it :(
 
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Michael Sewell said:
Edit:
Due to slow typing and distractions, [user]Triggaaar[/user] pretty said it, and beat me to it :(
Click to expand...
Well at least we said the same thing, so no embarrassing clean up operation is required.

If you want a wide aperture and maximum sun overpowering results, then do as Mahoney said, and use an ND filter while at your max sync speed (or just past it and crop).

PS - Michael, did you call me pretty :love:
 
Michael Sewell said:
If that's a dSLR you're using, it's not straightforward HSS you're implementing, as the flashgun is actually"strobing" it's light at a reduced output. ok if you are pretty much nose to nose with your subject, but it soon loses it's intensity with any distance.

Edit:
Due to slow typing and distractions, [user]Triggaaar[/user] pretty said it, and beat me to it :(
Click to expand...

I'm aware of how it works and youre right, the power and therefore range of the flash is greatly reduced. In the example I mentioned I was maybe 4' away, framing at approximately 3/4 length (subject standing) with a 24-70.

Higher powered lighting would be better, but then you are stuck within the sync speed limitation so you need a LOT more power.
 
Johnd2000 said:
I'm aware of how it works and youre right, the power and therefore range of the flash is greatly reduced...

Higher powered lighting would be better, but then you are stuck within the sync speed limitation so you need a LOT more power.
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Are you sure you know how it works? Being stuck within the sync speed limitation does not mean you need a LOT more power - you need LESS power at the sync speed than you do when shooting faster than the sync speed.
EDIT - but I think I understand your point
 
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Triggaaar said:
Are you sure you know how it works? Being stuck within the sync speed limitation does not mean you need a LOT more power - you need LESS power at the sync speed than you do when shooting faster than the sync speed.
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what 'e sed! :plusone:
 
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One option is open shade - flagging the sunlight from the subject (say, for portraiture) allows you to control how you light the subject (and be able to use a wider aperture) while knocking the ambient down using a fast shutter speed. I use this tactic to allow the use of a softbox when, in direct sunlight, I'd be running out of power AND having to use a high f/number. ...

Of course, there are some instances when you can't get the background dark enough, even on ISO, and that's when I'd either employ FP Sync if subject-to-light distance isn't great, or where ND filters can help bring the exposure down to something more manageable....
 
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redmonkee said:
Wow cheers for all the advice. :thumbs:

i thought I was asking a dumb question but now i'm glad I did :)

You say i could use an ND at my maximum Sync speed? What leven ND would you recommend?

I have a 10 stopper but I figure this would be way too much :shrug:
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In all honesty, this type of imagery is seat of the pants stuff, so give your ND a try, and then go from there.
Mind you, a tenner is likely to be a bit much.
 
Good advice from Michael - it's a case of feeling your way in to find things that suit what you want to achieve. NDs are pretty good value (unless you have a massive front filter thread), and the screw-in ones make life easy. I generally carry +2 and +4 ND filters and they help me enough, although I think i'd struggle getting exposures like f/1.8 @ 1/250th in bright sun with those filters....
 
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You could experiment with your ND10, but it is a bit much, even with increasing your iso a few stops.
Although increasing your shutter speed past the sync limit will reduce the power from your flash, it's still a good way of reducing the effect of the sun, so this is the easiest thing for you to try. Take a couple of shots at 1/2000 and 1/4000 and see what you get. If you can have the flash close enough, that's the easiest solution.
 
I'll have a go with the 10 stopper but the trouble i'll have is composing my image as its impossible to see anything when using this.

Another question I have and again sorry if it's a basic one.
I have a Canon 580EXII and also a YN560 is it possible to fire the 580EX off camera with the Yongnuo Radio triggers and have the 580EX fire the slave YN560?

Or does the 580EX have to be on camera to fire the YN560?
 
As long as there's a camera-to-flash signal using the triggers to fire the Canon unit, that will in turn set off the slave on the other flash. The Canon doesn't have to be on-camera.... it's a system I used to use, triggering an off-camera SB800 which then flashed and triggered my other speedlight set to slave (SU-4) setting. Meant I only needed one trigger and one receiver when I was skint :)

Don't know if there's any pre-flash settings on the 580 that need to be turned off for manual use, but the other thing you need to be mindful of is the optical signals (the flash) actually working outdoors. If there's not much distance between the two flashes there shouldn't be a problem but put tens of metres between the two and you are pushing the performance of the slave cell because it may not pick up the flash mixed into the sunlight. Best to fire both using receivers that are tuned into the trigger :)
 
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redmonkee said:
You say i could use an ND at my maximum Sync speed? What leven ND would you recommend?
Click to expand...

Using the Sunny 16 exposure guideline as a starting point you could shoot in brightly sunlit conditions without an ND filter at....

1/100 and f/16 at 100 ISO
1/200 and f/11 at 100 ISO
1/250 and f/10 at 100 ISO

So decide what aperture you wish to shoot at and work out the number of stops difference between that and the figures above and you will know how many stops of ND you need to correctly expose a sunlit background. If you want to creatively underexpose or overexpose the background then you'll need to factor that in.

Assuming you can only sync at 1/200 max then to shoot at f/8 you'd want an ND2 filter. To shoot at f/5.6 you'd want an ND4. To shoot at f/4 you'd want an ND8. To shoot at f/2.8 you'd want an ND16 etc. etc..

If you can frame the shot so the shutter shadow is not visible within the scene then you may be able to shoot above your sync speed if you go off camera with your flash. You can make the shutter shadow invisible by having it fall in the sky (need to invert the camera) or on a distant background where the flash has no visible effect. You could also shoot with loose framing and crop the shadow out in post. This blog entry will explain further - http://earthairfirephotography.blogspot.com/2011/02/how-to-increase-your-flash-sync-speed.html.
 
I've popped outside and taken a couple of shots to show the difference between shooting at max sync vs max speed.

Camera on a tripod. First shot at max speed, then second shot at max sync speed, using ISO adjustment and ND filter to give an equal ambient light. That way we can just see which shot provides the brightest flash.

1st shot - 1/8000, f2.8, iso200 flash on manual full
2nd shot - 1/250, f2.8, iso1600 (I make that 8 stops) + ND 9stop (who knows)

So, for max effect of overpowering the sun, I think you shuld stick to your max sync speed, and use an ND filter if necessary.

Shot 1

Flash_vs_Sun-1.jpg



Shot 2

Flash_vs_Sun-2.jpg
 
If it's bright sun that you want to over-power, the theory is simple (big flash, ND filter) but the practise is much harder.

Assuming full sun, take Tim's Sunny-16 numbers and work that back to how much flash power you need to beat that. It's a lot. Rule of thumb is that you'll need at least 400ws with even a modest sized modifier at 'normal' shooting distances, which is 4-6x the output of even the biggest hot shoe guns. You can forget HSS unless you have a whole bank of the things.

Then if you want low f/numbers, you quickly run into x-sync problems and need an ND filter to pull the shutter speed down. You won't need ten stops, but three or four at least, depending on the ambient level, ISO etc.

I find four stops of ND quite difficult to work with in bright light. The viewinder is dark and it's hard to see what you're doing, let alone nail the focus at f/2 or something.

By far the easiest way is to chose a day, or time of day, when the daylight level is lower, and not to shoot in full sun. Even a cloud will cut the level by a couple of stops, and an overcast day is less still, later in the day etc. That should be enough to make things workable with a big hot shoe gun (or two) if you keep it close, and a modest ND filter.
 
HSS only works with on camera position, there is a limitation on what it can do.
I tested a few cases and concluded that:
1 HSS only works for on camera flash on reduced power output. For overpowering the Sun, it limits camera position.
2 Ranger flash head on remote trigger is also limited by camera sync speed. However this could work with higher output, although ND filter on camera may required to reduce overall lighting
3 ETTL sync cord doesn't transmit HSS signal. It also by-pass camera-speedlite sync 'lock'. So in effect works like remote trigger.
4. ETTL sync cord 'boosts' sync speed to 1/250 without obvious 'dark band'.

See the photos in my blog:
http://blog.jingphotography.co.uk/2011/07/high-speed-sync-experiment.html
 
squarepeas said:
HSS only works with on camera position, there is a limitation on what it can do.
I tested a few cases and concluded that:
1 HSS only works for on camera flash on reduced power output. For overpowering the Sun, it limits camera position.
2 Ranger flash head on remote trigger is also limited by camera sync speed. However this could work with higher output, although ND filter on camera may required to reduce overall lighting
3 ETTL sync cord doesn't transmit HSS signal. It also by-pass camera-speedlite sync 'lock'. So in effect works like remote trigger.
4. ETTL sync cord 'boosts' sync speed to 1/250 without obvious 'dark band'.

See the photos in my blog:
http://blog.jingphotography.co.uk/2011/07/high-speed-sync-experiment.html
Click to expand...

I'm not understanding this. You're using a Pocket Wizard PlusII (manual only) which is perhaps interfering with your findings.

HHS works at all power outputs.
E-TTL sync cord retains all gun functions, including HSS and second curtain sync. It does not affect x-sync speed.
HSS also works off-camera using the native Canon wireless E-TTL system, but you lose second curtain sync.
 
squarepeas said:
That did take me by surprise. The Young Nuo OC-E3 didn't do HSS. Nope.



:thumbs:
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I don't see why it shouldn't but these things tend to be a bit quirky.

However, you can do HSS with Canon cord, and second curtain sync. You also get wireless remote HSS using the native Canon system, but this loses second curtain sync. PW Flex/Mini does both, and enhances both functions too.
 
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