Interior shots using on-camera flash

[Digital]

Shooting in manual mode, if you intentionally set the shutter speed to underexpose (using the high speed synch with my Nikon) the ambient light you can effectively darken the background, while keeping the aperture constant (e.g. f/8) since the flash (if set on automatic) will properly expose for the subject. Since this works for exterior shots, I believe it should work for interior shots as well. or am I all wet in this idea?


Bruce

[Manfred M]

Bruce - the short answer is yes, you can certainly do this, however it is not as straight forward indoors as it is outdoors.

When you shoot indoors, there are floors, walls and ceilings that reflect stray light from your flash, whereas outdoors, this is generally not the case and stray light will dissipate and will not strike your subject.

When you use this technique indoors, it can work as well; BUT you will have to account for any reflected light. Wall and ceiling colour, distance from these, etc. all have to be taken into account. Nicely said, you'll have to do some test shots to get the exposure you want.

As an example; this shot was taken using "snow white" seamless paper, but the subject and the lights were positioned far enough forward for the light drop off from the two studio lights to result in the grey look. The blue light camera left of the subject is from a piece of CTB gel attached to a light that was not used for the shot. The light reflected off the ceiling and seamless can caught the blue gel.




All that being said, when I shoot this way I do everything in manual mode. I find that auto is fine, but can be inconsistent. I will set up the lighting on the subject with an incident light flash meter and will take a reading of the background with a spot meter attachment on my flash meter, to ensure that I get the appropriate amount of drop off. The further back the background is from the flash, the darker it will be; BUT the walls and ceiling and positioning of the flash will all have an impact.

[jcuknz]

I would have said that the shutter speed will have little effect. I think Manfred's example is not mirroring the effect of what you asked and is a completely different lighting set up ie "[lights] positioned far enough forward ". I would suggest that to darken the background indoors it needs to be kept in the background and use the fall off in light as per inverse square of distance to produce the effect you are after ... coming in close to the subject with the flash on the camera as Manfred's example shows to a limited degree. So I think you are quite dry edit ... sorry a bit damp
In making this comment I am assuming that the ambient light is quite low, several stops below 'correct exposure'. With a highish level of light your application of syncro-sunlight applies indoors or out. An interesting application I had not thought of.

edit#2 my test of this morning shows me my correction was correct see #13

[pnodrog]

Just check that your pop up flash will support high speed sync and if so what will be the effective guide number at the various shutter speeds. I doubt that the method you outline will be effective or practical unless the subject is very close to the camera.

If you are referring to an auxiliary flash mounted on the camera please let us know the camera and flash combination you intend to use.

[Digital]

Thank you Manfred, and John for your comments. The setup I had planned to shoot does not include any walls nearby so I will experiment with various shutter speeds to determine if I get the effect I am after.


Bruce

[Digital]

Just check that your pop up flash will support high speed sync and if so what will be the effective guide number at the various shutter speeds. I doubt that the method you outline will be effective or practical unless the subject is very close to the camera.

If you are referring to an auxiliary flash mounted on the camera please let us know the camera and flash combination you intend to use.

L.Paul, thank you for commenting. The equipment I am using is a Nikon SB-600, and a Nikon D-300 set for high speed synch.


Bruce

[pnodrog]

L.Paul, thank you for commenting. The equipment I am using is a Nikon SB-600, and a Nikon D-300 set for high speed synch.


Bruce

Hi. For a long time I used a D200 and a SB-600 and found I got the best results by using either manual or aperture priority set to give 2-3 stops under exposed and then using positive flash compensation.

[Digital]

Hi. For a long time I used a D200 and a SB-600 and found I got the best results by using either manual or aperture priority set to give 2-3 stops under exposed and then using positive flash compensation.

L.Paul, I believe that my best method is to experiment to determine if I can get the results I am after. If I do, great, and if I don't at least I have learned something in both cases.


Bruce

[pnodrog]

Hi. For a long time I used a D200 and a SB-600 and found I got the best results by using either manual or aperture priority set to give 2-3 stops under exposed and then using positive flash compensation.

Bruce just a note. All the above is doing is changing the relationship between the ambient light and the power of the flash. Useful if you are doing interior shots of houses where you are trying to illuminate the interior while still correctly exposing a scene in a window, for portraiture without some sort of diffuser it will provide rather harsh lighting but it will however give you some control over how much light falls on a close subject compared to a distant wall.

Experiment and keep your thinking cap on as it obviously has been.

[Digital]

I will let CIC know how my "experiment" works.


Bruce

[Manfred M]

I would have said that the shutter speed will have little effect. I think Manfred's example is not mirroring the effect of what you asked and is a completely different lighting set up ie "[lights] positioned far enough forward ". I would suggest that to darken the background indoors it needs to be kept in the background and use the fall off in light as per inverse square of distance to produce the effect you are after ... coming in close to the subject with the flash on the camera as Manfred's example shows to a limited degree. So I think you are quite dry edit ... sorry a bit damp
In making this comment I am assuming that the ambient light is quite low, several stops below 'correct exposure'. With a highish level of light your application of syncro-sunlight applies indoors or out. An interesting application I had not thought of.

John - the problem I have in trying to answer this question is that there are so many variables when shooting flash in an interior setting.

In any flash shot, there are always three light sources we have to deal with.

1. The direct impact of the flash;

2. Spill over light from the flash; and

3. Impact of the ambient light.

If the source of flash is powerful enough, the impact of ambient light can often be ignored. If one is in a "proper" studio, with matte black walls, ceiling and floor and one controls the flash well, the spill light can usually be ignored as well. In other photographic situations, whether indoors or outdoors, life is not quite as simple.

A speedlight has relatively low power output, so I find that these can be trickier to use in indoor mixed lighting versus studio flash. Ambient light can play a far greater role with speedlights.

The other "issue" with flash versus ambient light is falloff via the inverse square law. The closer the flash is to the subject, the more drastic our falloff is. If I have my flash 1m / 40" from my subject, I will have 1/4 of the light hitting the background 1m / 40" behind the subject, at 2m / 80", that's down to 1/16th of the light, etc. This can be important in an ambient light situation as the contribution of ambient to the shot can exceed the flash contribution the further one gets back from the flash, so a longer shutter speed will increase the contribution of the ambient light to the overall shot. The HSS is an added complication as with higher shutter speeds, the contribution of ambient light will be reduced, but the so is the output from the flash.

The added complication is the contribution of the TTL metered light from the flash. The main problem I have with it is that it is so darn unpredictable; which is why I tend to shoot on manual (much more repeatable) and use a flash meter to boot. My usual approach is to meter the scene to get a correct exposure without any flash and then dial that back by a stop or two do decrease the impact of the background. I'll then meter amount of flash I need to properly illuminate the subject at the new aperture settings. So long as I don't change the subject to flash distance, I can shoot away all day long and get consistent results. Try that on TTL flash, and every time I move the camera and it picks up a different light ready, I have to play with flash exposure compensation to get the light the way I want it. I prefer the predictability of manual, but it's not always possible to do this.

The other key variable in indoor versus outdoor flash is the colour temperature difference between the light sources. Unless one is shooting in and around "golden hour", flash at its 5500K (or so) colour temperature is close enough to the ambient light colour temperature so that this is not an issue. Step indoors and try it, you have say a traditional tungsten setting of 2800K competing with the 5500L of the flash and the result can look downright awful if you don't get the flash with somewhere around 1/2 CTO to more closely match the ambient light. If shooting under fluorescent light, it's a bit more complex. My SB900 shipped with temperature compensating gels / holder so these do get used in these situations.

[William W]

Whatever the outcome of your experiment . . .

Shooting in manual mode, if you intentionally set the shutter speed to underexpose (using the high speed synch with my Nikon) the ambient light you can effectively darken the background, while keeping the aperture constant (e.g. f/8) since the flash (if set on automatic) will properly expose for the subject. Since this works for exterior shots, I believe it should work for interior shots as well. or am I all wet in this idea?

Why do you want to use HSS for interior shots?

It occurs to me, that it must be a very bright interior scene to warrant Shutter Speeds faster than the Flash X Sync and the typical suggested Aperture being F/8? (and also for larger Apertures)

Or you are shooting at a very high ISO for some reason?

What the X-Sync Speed on a D300? Around 1/250s, I guess.

For example: A typical indoor brightly lit Ballroom, the ambient is about: F/8 @ 1/60s @ ISO 1600. At that exposure, you're 2 under for ambient, just by moving the Shutter Speed to Flash Sync Speed.

I would have thought for mostly all usual shooting scenarios, one objective would be to use a lower the ISO if at all possible: so the brighter that the interior was most would usually want to lower the ISO, rather than bump the Shutter Speed to invoke the use of HHS and thus introduce the subsequent consequences of HHS:

> loss of Flash Power per each shot
> reduction of the Maximum Flash Working Distance
> loss of the ability of the Flash to freeze Subject Motion
> increased possibility of overheating cut-out being activated (if the Flash has one)
> possibility of slower recycle times

WW

[jcuknz]

I woke up this morning wondering if I was Wet or Dry ... so at 0541hrs I got up and took two shots at f/8 with the on-board flash .... one at 1/50 and the other at 1/1000 ... can you spot the difference?



EXIF will tell you 1/50 but which one is the base photo?

True I am using a bridge camera which without high speed flash enables me to choose any shutter speed I wish and the flash in both cases was simply opened and I am in force flash all the time with this camera.
In both cases the camera gave me the red light warning of incorrect exposure ... but what do cameras know
I was sitting in the dark in my workshop for both shots. When it gets light I must repeat the experiment .....

Back tomorrow with the answer

[Digital]

Whatever the outcome of your experiment . . .



Why do you want to use HSS for interior shots?





















It occurs to me, that it must be a very bright interior scene to warrant Shutter Speeds faster than the Flash X Sync and the typical suggested Aperture being F/8? (and also for larger Apertures)

Or you are shooting at a very high ISO for some reason?

What the X-Sync Speed on a D300? Around 1/250s, I guess.

For example: A typical indoor brightly lit Ballroom, the ambient is about: F/8 @ 1/60s @ ISO 1600. At that exposure, you're 2 under for ambient, just by moving the Shutter Speed to Flash Sync Speed.

I would have thought for mostly all usual shooting scenarios, one objective would be to use a lower the ISO if at all possible: so the brighter that the interior was most would usually want to lower the ISO, rather than bump the Shutter Speed to invoke the use of HHS and thus introduce the subsequent consequences of HHS:

> loss of Flash Power per each shot
> reduction of the Maximum Flash Working Distance
> loss of the ability of the Flash to freeze Subject Motion
> increased possibility of overheating cut-out being activated (if the Flash has one)
> possibility of slower recycle times

WW

Bill, it does not matter to me what shutter speed I use as long as I can obtain the desired effect; i.e. darkening the background.
If 1/60 will get me there or 1/8000 it does not matter. HSS is an option that I have; however if I do not need it to hopefully get my effect so be it

Bruce

[Digital]

I woke up this morning wondering if I was Wet or Dry ... so at 0541hrs I got up and took two shots at f/8 with the on-board flash .... one at 1/50 and the other at 1/1000 ... can you spot the difference?



EXIF will tell you 1/50 but which one is the base photo?


John, in your example how far is your subject from the background? The area I plan my shoot is an area that the wall is not near the subject. Looking at your pics it appears to me that this is exactly what Manfred was talking about (i.e. the light from the flash bouncing off the wall).
You have been very kind to go the extra mile with your comments to me. I appreciate that.

Bruce



True I am using a bridge camera which without high speed flash enables me to choose any shutter speed I wish and the flash in both cases was simply opened and I am in force flash all the time with this camera.
In both cases the camera gave me the red light warning of incorrect exposure ... but what do cameras know
I was sitting in the dark in my workshop for both shots. When it gets light I must repeat the experiment .....

Back tomorrow with the answer

[William W]

. . . it does not matter to me what shutter speed I use as long as I can obtain the desired effect; i.e. darkening the background.
If 1/60 will get me there or 1/8000 it does not matter. HSS is an option that I have; however if I do not need it to hopefully get my effect so be it.

OK. Understood.

Supplementing all that Manfred has written -

In simply terms it will be easier to have a dark background and make a good shot of it if:

> there is a larger Subject to Background distance than Camera to Subject Distance, a 2:1 or larger ratio is a good beginning.

> you do not use HSS (because of the reasons listed above) especially loss of Flash Power and reduction of Maximum Flash Working Distance.


A typical example that I would use to beginner Wedding Photographers is the B&G First Dance - (typically) The Camera is to be at about 12ft and the background crowd needs to be at about 25~30ft behind the B&G. Drag the Shutter at TWO stops under the Ambient Exposure and Flash as Key on the Subjects at FEC about minus 2/3 Stop.

WW

[Digital]

Bill, thank you very much for commenting. I hope to be able to attempt this shoot within the next few weeks. I will let you all know how this works out.


Bruce

[jcuknz]

The sun has woken up although hiding behind thick cloud ....





Bruce ... I think you are wasting your time if you hope to adjust the background indoors by shutter speed when indoors.

Basic flash as when I started doing syncro-sunlight back in the late fifties has not really changed and in low ambient light [indoors] the shutter speed has little or no affect on background levels and only in daylight ambient levels does the shutter have any effect which brings us back to the old maxim that "the aperture controls the flash and the shutter the ambient light"

Light from most sources falls off in strength at the inverse square of its distance from what it is illuminating .... this can be an irritation or can be used for the effect we want or by using a remote flash one can even out the flash to subject/background distances to minimise the effect.

At that time in the fifties I sold off my Leica [ cost to me s/h was NZP60] for a Japanese fixed lens camera[ NZP45 ] just so I would have a compur shutter for syncro-sunlight work which had appeared in my area by the top studio photographer using his Linhoff and I liked the idea for my candid work.
[ I still have a sneaking feeling that Japanese cameras are inferior copies and only when combined, as with Panasonic with German technology etc etc ]

It is the difference between the compur type shutter and the SLRs focal plane shutter, in those days with a sync speed of 1/30th, which in recent years has been changed with the ability of flash units to prolong their flash, though weakened, which permits highspeed flash.

[Digital]

John, the faster SS did darken considerably the light coming from the window. In fact it makes it appear there is a solid wall behind the subject as opposed to a window. IMHO this leads credence that to the effect that increasing the SS will (as shown by your example) darken (underexpose) the ambient light in the background. This is the effect I want to achieve.
Thank you very much.

Bruce

[pnodrog]

Bruce just remember when using the high speed sync mode the flash will be illuminating the entire scene with a series of high frequency flash strobes but the camera will only be capturing part of of the scene governed by the width of the gap between the front and rear shutter as they move down the frame so a lot of the flash's power is being wasted on areas not being recorded. Therefore the higher the camera's speed setting the narrower the gap and the less efficient and effective the flash illumination will be.

The maximum ratio of flash to ambient will be achieved at the fastest sync speed that enables the flash to discharge all its power in a single pulse with the shutter wide open.

There are no free lunches...