BetterPhoto Q&A
Category: New Questions

Photography Question 
Linda Kessler
 

How to use a flash on bright sunny days


using a F100, S-28 flash, I am trying to use a slight flash to eliminate shadows, with subject in sunlight and background in sunlight as well. Using Tri-X 400 film, attempting to get the distance with some focus, matrix metered for distance at F11/250. Was a bit overexposed but couldn't shoot faster and didn't want a smaller F stop. Shots came out underexposed (Asian family). Used matrix metering.

A different scenario is with subjects in open shade with sunny distance (backlit). Want to obtain enough light on subjects and get focus in distance as well.

Don't want photos appearing they were with a flash, just want slight, flash with natural look.

How do I use less power on the flash? From research I read I could change the flash compensation to -7. OTher sources says to make it +1 or to open up the aperture by 1 stop.

I am a bit confused. Then there's also using slower film as an option, but usually only use Tri-X 400.

Thanks,

Linda


To love this question, log in above
10/23/2007 7:33:28 AM

 
Kerry L. Walker   "using a F100, S-28 flash, I am trying to use a slight flash to eliminate shadows, with subject in sunlight and background in sunlight as well. Using Tri-X 400 film, attempting to get the distance with some focus, matrix metered for distance at F11/250. Was a bit overexposed but couldn't shoot faster and didn't want a smaller F stop. Shots came out underexposed (Asian family). Used matrix metering."

I'm confused. Were they overexposed or underexposed. You said both. Assuming they were overexposed, use a ND filter to cut down on the light so you can still use the same f/stop & shutter speed. If they were underexposed, just use a slower speed.

"A different scenario is with subjects in open shade with sunny distance (backlit). Want to obtain enough light on subjects and get focus in distance as well."

Meter for the background and use flash to light the foreground (incl. subject). No flash comp. I assume you mean you want to maintain the correct exposure for the background rather than maintain focus for the background. If you want to maintain good fucus for the background, you will need to use as small an aperture as possible.

"How do I use less power on the flash? From research I read I could change the flash compensation to -7. OTher sources says to make it +1 or to open up the aperture by 1 stop."

I assume you are using the SB-28 flash, which I have. Set your flash comp to -.7 or -1 - if you are metering for the subject and not the background.


To love this comment, log in above
10/23/2007 8:38:31 AM

 
Jon Close
BetterPhoto Member Since: 5/18/2000
  WRT the first problem - keeping aperture at f/11 or wider and min. shutter speed of 1/250 with fill flash in bright sunlight ==> Use a neutral density filter.

Balanced fill-flash is completely automatic with the F100 and SB-28 in TTL mode. If you don't like the balance between ambient and flash exposures, Adjust the ambient light exposure via shutter speed and aperture and apply flash exposure compensation as you like.

Re: >>"How do I use less power on the flash? From research I read I could change the flash compensation to -7. Other sources says to make it +1 or to open up the aperture by 1 stop."<<
Adjusting flash exposure compensation is the most direct method for lessening the flash output in TTL and Auto modes. I believe "-7" should be "-0.7" which would be -2/3 of a stop. In the non-TTL Auto mode, the speedlight can also be adjusted to give less (or more) output by varying the ISO and Aperture settings on the flash from from those on the camera. See pp. 71-75 of the SB-28's instruction manual.


To love this comment, log in above
10/23/2007 8:54:17 AM

 
Christopher A. Walrath
BetterPhoto Member Since: 4/25/2006
  Just my two cents. Light will increase exposure at a much greater rate in lower exposure zones than in higher ones. If any of my subject is in the brightest light with a big fall off in luminosity toward the shadows, I meter the highlight about zone 6 and let the flash bring the rest of the subject up to speed, so to speak. This might raise a subject area that lays in zone 1 (deepest shadow) to about zone 4, zone 2 to about 5, 3 (average shadow) to 5 1/2, 4 to 6, 5 (light shade) to 6 1/2, zone six will have less than one zone increase in exposure. This severly reduces contrast by bringing up deep shadows and recording data in normally blacked out areas. But be mindful of the background as Kerry mentions. If your subject is bright and your background is in deep shadow, you will lose detail in the background unless of course you go for this effect in emphasizing your subject.


To love this comment, log in above
10/23/2007 7:31:30 PM

 
Linda Kessler   Thanks all.

Just to clarify -

1. First scenario, is subject and background is in bright sunlight, shot around noon. Wanted slight fill flash for shadows, or perhaps I do not need a flash. Shot Tri-X 400. Couldn't fudge the F-Stop of shutter in order to get distance and sinc at 250. Metered using matrix for distance, using F100, SB-28, using fill flash. Photos came out underexposed, although color film came out fine, also at 400 Portra ND.)

Questions:

A. Should I even be using a flash?
B. If so, should I use flash compensation, or opening up one F stop on the lens?
C. Should I use a neutral density filter?
D. Should I use slower film?

I do not want the photos to appear as though a flash was even used, want a natural look, with light in the distance.


2. Scene 2: Morning light, subject was in open shade, distance was sunny.
Shot using central metering, metered with a grey card, and rated 400 film to 250.

A. Didn't use a flash, but background was blown out, subjects a bit underexposed. Should I have used a flash?

B. Flash compensation or opening up one F stop on the lens?

C. Slower film?

D. Neutral density filter?

Never used a netural density filter before, and not too much experience with the flash.

Hope this clarified my situations.

Thank you in advance,

Linda


To love this comment, log in above
10/24/2007 3:59:05 AM

 
Christopher A. Walrath
BetterPhoto Member Since: 4/25/2006
  Scenario 1: If you subject is a white/caucasian person, I would meter a gray card in the same light and open up one stop to place their skin on Zone VI. Shoot in manual around your sync speed and fire the flash to fill the shadows. Darker skin, drop it a Zone but watch that background. Don't use a ND filter, this would increase your contrast and your problem. A slower film would definitely give you some elbow room, even if only ISO200.

Scenario 2: Meter your subject and place them about one stop lower than you normally would. Unless you might wanna kick around isolating your subject by zooming in on your subject and let the background white out. Slower film won't help much, again ND would increase contrast. Or figure you flash factor for the exposure value of your subject and see how far your flash would bring your subject up in comparison to the reading on your background. Try to keep the seperation no more than about two stops to get detail in both.


To love this comment, log in above
10/24/2007 7:22:18 AM

 
Log in to respond or ask your own question.