Indoor flash work for backlit candid shots Q's

[Stagecoach]

I have been approached to consider undertaking some photos that can be used in news letters, website and awareness documents for an organisation that operates various facilities for children with disabilities.

Amongst my already long list of questions, considerations and planning items prior to visiting the facilities for a pre-shoot meet is the subject of flash use, which may or may not be allowed.

At present I am investigating the specific situation where I have no option other than to shoot a subject in a room with strong lighting behind them, e.g windows and being able to use flash, ideally bounced. The flash I have available is the SB600 and a diffuser for it.

So my question is, does anyone have any tips on achieving the best lighting results. Based on a 1/4 body shots, landscape with my gear.

Grahame

[rpcrowe]

I would consider a few things... Ideally, you could shoot this in a vertical with as little of the window showing as possible. Heck, ideally, you would not have to shoot with the window at the rear of your subject...

If you are forced into shooting a backlit situation in a landscape format, I would meter the light coming in from the window and expose about one stop below that. I would use bounce flash with a reflector/diffuser (like the Joe Demb Flash Diffuser Professional: https://www.bhphotovideo.com/bnh/con...m=Y&sku=833251 ) with the flash in manual.

Expose so that the flash is about one stop brighter than the exposure for the window light.

Ensure the flash is not bouncing back at you from the window.

Also ensure that the light coming in from the window is not causing flare.

If possible, shoot at a time when the light is not shining directly into the window...

I am sure that there are other ways to do this which will be pointed out by our CiC friends...

[Stagecoach]

Thank you Richard

I would consider a few things... Ideally, you could shoot this in a vertical with as little of the window showing as possible. Heck, ideally, you would not have to shoot with the window at the rear of your subject...

I'm looking at worse situations that may be encountered but if and where possible would try to avoid windows/doorways with strong light in the framing. From my understanding so far these are not going to be staged shots but grabs to portray the children in natural location and activity, hence I am thinking landscape will generally work best.

If you are forced into shooting a backlit situation in a landscape format, I would meter the light coming in from the window and expose about one stop below that. I would use bounce flash with a reflector/diffuser (like the Joe Demb Flash Diffuser Professional: https://www.bhphotovideo.com/bnh/con...m=Y&sku=833251 ) with the flash in manual.

Expose so that the flash is about one stop brighter than the exposure for the window light.

I have no reflector for my flash/diffuser but can easily make one up and experiment beforehand.

Based on your suggestions I'll run some tests (I have a good sized room with very bright light coming in from windows) and see what's achievable, using anticipated speeds/apertures/distances/bounce angle.

I'm also thinking about the best mode to use to reduce fluffing about changing settings and recall the D800 has a quirky mode in manual to use TTL flash.

Ensure the flash is not bouncing back at you from the window.

Also ensure that the light coming in from the window is not causing flare.

If possible, shoot at a time when the light is not shining directly into the window...

Good points and once I'm familiar with the locations it may be that morning or afternoon is a preference.

I am sure that there are other ways to do this which will be pointed out by our CiC friends...

I expect so

[rpcrowe]

Grahame,

Diffuser reflectors are handy additions foe any hotshoe flash...

It is relatively easy to fabricate a very acceptable reflector by attaching (by way of an elastic band or gaffer's tape) a piece of card to any hotshoe flash. Much has been said for using a business sized card but, I would prefer to use a larger size piece of heavy paper or white foam board.

You can find plans for more involved DIY Diffuser/Reflectors on the Internet - especially on YouTube. This guy (if you can stand his sick humor) has one that looks quite good.
https://www.youtube.com/watch?v=KD9EMENmEQQ&t=31s

However, here are a few from eBay which are inexpensive. I have tried a lot of these diffusers, always searching for the least expensive and easiest to use so I can buy them and give them to my dog rescue volunteers.

I like this one because it is flat and can be carried in the front pocket of a camera bag or the pocket of a camera vest. I bought one on eBay for far less than the five dollar price quoted here...
http://www.ebay.com/itm/Flash-Diffus...x/291315416578

This diffuser also does a pretty nice job for most types of photography by using the flash head pointed straight up. It has a shiny metallic interior at the back which does a nice job of reflecting the light through the white fabric in front. By placing the flash head at a 45 degree angle forward, it can be use effectively for closeup or macro shooting.
http://www.ebay.com/itm/Portable-2-i...d/161963179958

I use the Joe Demb Flash Diffuser Pro for most of my shooting and I like it quite well. The reflector portion of this unit can be adjusted in angle depending on how much light I want to direct forward. By placing the reflector at a 45 degree angle forward, I can use this unit where I don't have a ceiling to bounce off. I tried a Chinese knock off of the Demb Flash Diffuser Pro and it fell apart after a couple of uses. I have been using my unit for almost ten years now and except for replacing the double Velcro tape, it has needed no upkeep. Granted, it seems expensive but, it lasts and lasts and provides great lighting...

Finally, this diffuser is so simple that it is hard to believe it works, But it works pretty well and can be carried in a shirt pocket... The used to be a lot less expensive. I purchased two of them for less than two U.S. Dollars each (including shipment from China).
http://www.ebay.com/itm/Compact-Port...97.m4902.l9144

Note: I am not keen on the StoFen type of diffuser or the Gary Fong units...

[Stagecoach]

Thanks for the additional info Richard, I can see me getting a sewing kit out in the next few days and experimenting

Today I visited the facilities at the first location and am clearer of the challenge this project is going to be. What was most pleasing is that I'm dealing with someone that knows exactly what they want and what they don't want.

Flash use, where needed is generally allowed and I believe in many of the locations is going to be necessary due to the poor lighting so I'm looking at available backup/increased power units available locally at present.

One challenge is the small size of some rooms where specific operations are undertaken and I have no lens with VR/IS in the 35 to 80 range which would make me happier

[rpcrowe]

When I purchased the 17-55mm f/2.8 IS lens (bought it when it first came out, selling my 24-70mm f/2.8 Mk.i lens to cover the cost). I first thought that I would never need IS in a lens of this focal length. But, I have been using the lens for over ten years now and it is one of the reasons (along with the 7D and 7D2 cameras) that I have remained with the crop format. I just love this lens!

[Manfred M]

One challenge is the small size of some rooms where specific operations are undertaken and I have no lens with VR/IS in the 35 to 80 range which would make me happier

Duration of the flash is in the order of 1/1000th sec, so unless there is a lot of ambient light impacting your shot (and you suggest that there isn't), the speed of the flash should freeze the image, even with a bit of camera shake. My most used lens is my 24-70mm lens which has no VR. The range of focal lengths you are planning to shoot with really don't need it.

[William W]

Duration of the flash is in the order of 1/1000th sec, so unless there is a lot of ambient light impacting your shot (and you suggest that there isn't), the speed of the flash should freeze the image . . .

Hi Grahame, I've been delaying my response. I require clarification: in the OP you were asking about a specific situation, viz: " no option other than to shoot a subject in a room with strong lighting behind them."

My response would address Flash Usage in a strongly lit room (typical Ambient EV = 12~13).

Please clarify if you will be dealing with some situations where there will be strong ambient light, through the windows.

Ta,

WW

[Stagecoach]

Richard, Manfred

I am more than likely worrying about this unnecessarily, as you say Manfred in those situations where the flash will be used I can sync at 1/250th and at the focal range of the 28-75mm non VR Tamron I have there should be no problem if care is taken. For using it in brighter light I have the advantage of the ISO capability on the D800.

For other ranges I have the Nikon 16-35 VR f/4 and the Nikon 80-400 VR f/4.5 up.

[Stagecoach]

Hi Grahame, I've been delaying my response. I require clarification: in the OP you were asking about a specific situation, viz: " no option other than to shoot a subject in a room with strong lighting behind them."

My response would address Flash Usage in a strongly lit room (typical Ambient EV = 12~13).

Please clarify if you will be dealing with some situations where there will be strong ambient light, through the windows.

Ta,



WW

Hi Bill,

Yes, from my visit today I can confirm there are a couple of rooms that have strong ambient daylight coming in through windows and it is quite likely that areas of these windows will be within the frame (when/where it's not possible for me to control this). That light is strong compared to the general lighting of the room which is dim widely spaced small flourescents.

WRT Manfred's response this is applicable to other small rooms with almost no outside light coming in and what we would call very poorly lit, where the flash will be the predominant lighting of the subject.

Edit : For Bill, I also noted in the rooms that had the strong daylight coming through the widows this was only from one aspect.

[William W]

. . . I can confirm there are a couple of rooms that have strong ambient daylight coming in through windows and it is quite likely that areas of these windows will be within the frame.
. . .That light is strong compared to the general lighting of the room which is dim widely spaced small flourescents
. . . I also noted in the rooms that had the strong daylight coming through the widows this was only from one aspect.

Thanks.

In this Lighting Scenario, whether shooting inside or outside, my primary consideration is always the MFWD (Maximum Flash Working Distance).

The point is, you will probably want the Flash to be used as “Fill” for the scene (that is so there is definition in the windows and the bright areas of the scene) BUT the Flash is actually acting as the KEY LIGHT for the Subject(s).

Expressed another way, whatever the EV of the Light coming through the window, the Flash has to overpower that ambient light the same way it has to overpower the Sunlight when shooting a Portrait, outside with a Subject in back-lit sunlight.

***

Hypothetical scenario for consideration for planning and testing -

> Let’s assume you’re shooting a group of children using (equivalent) 35mm lens on Full Frame camera.

> Your SB600 has a GN = 30/96 m/ft @ ISO100 @ 35mm Flash Zoom Head.

> Dunno what your Max Flash Sync is, let’s say Max. F.S. = 1/200s

> The window light is “bright” from direct sun, but is diffused through shear curtains, so let’s say the window light spills in at EV = 12. (3 stops under “F/16 Rule”)

> Ambient exposure for the area of scene which is lit by the Window Light = F/8 @ 1/200s @ ISO100 (3 stops under “F/16 Rule”)

> For DIRECT Flash to fill, at equivalent of the ambient exposure, the rough calculation of MFWD is –
96/8 = 12ft (30/8 = 3.75m)

CAUTION – Bounce or Diffuse the Flash you will lose “Flash Power” hence reduce the MFWD.

Conclusion – be very careful about using BOUNCE or DIFFUSED Flash if there is really strong light coming through the windows and your desired outcome is to use the Flash to balance the Back Light that is falling on the Subject(s).

WW

Note - "Flash Power" - the power out of the Speedlite Flash is NOT changed when using bounce or diffused, that's why the colloquial phrase was expressed in inverted commas.

[William W]

BTW -

. . . I am more than likely worrying about this unnecessarily . . .

Disagree. Occurs to me as professional planning. I wouldn't expect any less from you.

[Stagecoach]

Many thanks for this Bill.

I will sit and digest it carefully prior to rushing back with any questions.

Grahame

Edit : for info I will be undertaking the first session mid next week which gives me a good few days for preparing.

[Stagecoach]

CAUTION – Bounce or Diffuse the Flash you will lose “Flash Power” hence reduce the MFWD.

Conclusion – be very careful about using BOUNCE or DIFFUSED Flash if there is really strong light coming through the windows and your desired outcome is to use the Flash to balance the Back Light that is falling on the Subject(s).

Bill,

Based on your advice and upon the same specific lighting scenario I am going to undertake some tests to see exactly what is achievable with the SB600. Luckily I have a room where I can easily set up a strongly backlit or side lit scene to simulate as an example a child sat at a table playing with something.

From what I have learnt distance is necessary so as not to disturb the children from acting naturally so I am basing tests on a shooting distance of 3m which at FL 75mm gives a 1/4 body profile for an adult with a DoF of 460mm at f/8. (I knew that crib sheet would come in handy again)

Taking note that the highest shutter speed I'm going to be able to use is max sync of 1/250th I can confirm subject distances achievable with direct, bounce and diffused flash.

In addition I'm going to try and work out exactly what is happening when TTL flash is used with the D800 in manual mode as I get some decent results with it when snapping away but have not got a clue why or if it responds to compensation in that mode and can find no info.

Grahame

[Manfred M]

In addition I'm going to try and work out exactly what is happening when TTL flash is used with the D800 in manual mode as I get some decent results with it when snapping away but have not got a clue why or if it responds to compensation in that mode and can find no info.

Don't forget that you can dial in exposure compensation (EC) and flash exposure compensation (FEC) separately. I've never quite figured out how these seem to work together; my understanding is that Canon takes a different approach than Nikon does in this. I find I try to shoot flash on manual other than in "Run & Gun" situations as at least I can understand what is going on and find I get more consistent results.

[Mike Buckley]

To understand the details of using exposure compensation and flash compensation, conduct a search in your camera's manual of those two terms. They're added together when both are used at the same time on your camera.

I also recommend that you look up TTL BL and iTTL to get an understanding of how those two modes work and when they are typically most helpful.

Having said that, in this situation I would probably set the camera's metering mode to Manual, the shutter to sync speed, the aperture to produce whatever depth of field I prefer, Auto ISO to OFF, ISO to the lowest value I can get away with taking into account whether there is a need for fast recycling time, and the flash output controlled using its manual mode. I would constantly be checking the histogram throughout the shoot.

[Stagecoach]

Don't forget that you can dial in exposure compensation (EC) and flash exposure compensation (FEC) separately. I've never quite figured out how these seem to work together; my understanding is that Canon takes a different approach than Nikon does in this. I find I try to shoot flash on manual other than in "Run & Gun" situations as at least I can understand what is going on and find I get more consistent results.

For the majority of time I also use flash manually Manfred but it is generally in situations where I have the time to trial and prepare prior to the captures. The situations are now also often those for which I have had prior experience and know the capabilities of the flash, e.g. burst rates achievable at specific powers and distance, coverage at various FLs but most of this is with respect to using it as key light in dark surroundings.

My trials today should give me some good knowledge of exactly how EC and FEC affect the flash when in TTL/TTL BL with the camera in manual.

[Stagecoach]

To understand the details of using exposure compensation and flash compensation, conduct a search in your camera's manual of those two terms. They're added together when both are used at the same time on your camera.

This is something I have read before but never taken the time to digest it Mike. I can incorporate this into my trials.

I also recommend that you look up TTL BL and iTTL to get an understanding of how those two modes work and when they are typically most helpful.

I have this article http://dpanswers.com/content/nikon_flash_use02.php and also found another excellent one yesterday that I can't find the link to at the moment that suggested the mode to use in the specific situation we are discussing which was with the camera set in 'programmed mode' interestingly with TTL BL in use.

Having said that, in this situation I would probably set the camera's metering mode to Manual, the shutter to sync speed, the aperture to produce whatever depth of field I prefer, Auto ISO to OFF, ISO to the lowest value I can get away with taking into account whether there is a need for fast recycling time, and the flash output controlled using its manual mode. I would constantly be checking the histogram throughout the shoot.

I will certainly be using the camera in manual mode and could use flash in manual, but I'm looking for preferably a faster method where I may be able to leave the flash as is and just concentrate on setting camera exposure.

[Mike Buckley]

how EC and FEC affect the flash when in TTL/TTL BL with the camera in manual.

My notes indicate that Nikon recommends not using them when using TTL BL.

[William W]

. . . I am going to undertake some tests to see exactly what is achievable with the SB600.

Grahame,

I really think this is the best way to proceed, after digesting the theory.

When we cut over to digital from film, we also changed our 135 format SLR System. Canon was a whole new world to me, especially their Speedlite System. I needed to be full bottle on their Speedlite system, because on-the-hop Flash Fill Portraiture was one of the basic foundations of our Wedding Portraiture Business. I practiced many different scenarios, for several months, before I shot my first job with our new Digital DSLRs. At the time I was fortunate enough to befriend a W&P Photographer who was extremely knowledgeable and experienced with Canon Speedlites - I owe the bulk of my now detailed knowledge to her tutelage: Nadine Ohara.

It's been over a decade since I used Nikon Flash and their system has evolved over that time and is indeed different to Canon. It is important that these differences between brands be recognized, especially when we get to finesse, detail and nuance, because whilst all Flash Photography has basic premises which are common, the devil is always in the detail when we want excellent and consistent results and/or when we are shooting in complex or difficult scenarios.

Fortunately there is a generous amount of Nikon knowledge and experience which is spread willingly, here at CiC.

Break a leg.

Bill