rob_x2004 Posted June 29, 2009 Share #1 Posted June 29, 2009 Advertisement (gone after registration) I have an incident of say 30th f/5.6 (at whatever ISO) Set my camera to 50th f/5.6 to render the background a bit under Flash (with its GN) power at EV-4 should give subject at six feet an exposure requiring f/5.6 Set the flash EV say -5. Am I in the right sort of ball park? Link to post Share on other sites More sharing options...
Advertisement Posted June 29, 2009 Posted June 29, 2009 Hi rob_x2004, Take a look here Fill flash question.. I'm sure you'll find what you were looking for!
guywalder Posted June 29, 2009 Share #2 Posted June 29, 2009 Rob, depends what effect you are after I suppose.... I would be inclined to set the 30th/5.6 on the camera and then -1, or similar, on the flash so your main subject is correctly exposed and the fill lifts the shadows without adding much to the highlights. At least that is my approach on the few occasions I use fill flash. Your description sounds like under exposure for ambient, And under exposure for flash... you usually want one of the exposures to be 'correct' Here are a couple of good resources on flash: Neil Turner: Neil Turner | photographer Strobist: Strobist might be easier to find what you are after quickly on Neil's sight, under 'essays'. Guy Link to post Share on other sites More sharing options...
rob_x2004 Posted June 29, 2009 Author Share #3 Posted June 29, 2009 Thanks for that Guy. Neils site looks like a bit of a gift. Will go through it. I might also be confusing my description. Am working fully manual, and setting the "power to -4", which at the f/stop 5.6 should give me a range of six feet. Flash GN/f-stop would be twenty four odd feet. Was also figuring on a cumulative effect, ambient plus flash on the subject, with the background far enough behind to be pretty much unaffected by the small flash. So I can see your logic for getting the background right, just that some parts of the subject are going to be lit by ambient. Start practicing I guess. An LCD would be nice wouldnt it. Link to post Share on other sites More sharing options...
guywalder Posted June 29, 2009 Share #4 Posted June 29, 2009 so your flash exposure will be 'correct' and your ambient exposure will be 2/3 under? (30th vs 50th) In which case you will have a 'flash lit' picture with typical flash fall off (assuming I now understand your description...) I'm not sure how cumulative light is in these circumstances. I think that other than around 1:1 the stronger source will dominate. But with 1:1 flash:ambient you usually get very obvious double shadows... hence the 'typical' fill flash setting of -1 under ambient, strong enough to lift shadows but not strong enough to create flash shadows. I guess the -1 setting depends on the harshness of your ambient.... Link to post Share on other sites More sharing options...
redbaron Posted June 29, 2009 Share #5 Posted June 29, 2009 Those ratios sound more like a key light effect. If your flash is either on the camera or very close to the lens axis the lighting on the subject won't look too nice. Probably very close to a digital point-and-shoot. A typical fill flash ratio is one or two stops under the ambient reading. The easiest way to do it is to set the ISO on the flash to one or two stops higher than set on the camera and set both camera and flash apertures the same. That way the flash thinks you're using more sensitive film and pumps out less light for a given aperture. The ambient light can also then be varied using the shutter speed. I would suggest mounting a camera on a tripod and taking a roll of tests of a suitable subject. A mannequin's head, for example. Make sure it's in full sun and try different ranges of exposures. Link to post Share on other sites More sharing options...
rycm Posted July 1, 2009 Share #6 Posted July 1, 2009 This is where a Digital M8 does a great job. Put on the flash, fire away, check the histogram, adjust shutter or flash intensity, recompose and shoot! With film.. hmmm.. that's expensive. I prefer to use auto-flash on my M7. But with the M8, Manual flash for full control and off camera works best. Link to post Share on other sites More sharing options...
rob_x2004 Posted July 2, 2009 Author Share #7 Posted July 2, 2009 Advertisement (gone after registration) Thanks for the responses. Learning stuff day by day. My only option at the moment is manual and film, and manual flash. Getting the basics right, then learning how to massage the theoretical around the found lighting and film type. My black art is still in muddle grey:D. Link to post Share on other sites More sharing options...
imported_peter_m Posted July 2, 2009 Share #8 Posted July 2, 2009 My black art is a lot whiter then yours Didn't do to bad with an old Vivitar 283 . Getting some measurement with a flash meter helps getting things figured out. Of course make a note or two so you remember what you did. Peter Link to post Share on other sites More sharing options...
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