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<blockquote data-quote="WayneF" data-source="post: 182951" data-attributes="member: 12496">The lighting does look real good.&nbsp; Auto FP flash mode maximum is around 1/5 power, about -2.3 stops down&nbsp; from regular flash mode.&nbsp;&nbsp; Five FP flashes working together would match&nbsp; same one flash power in regular speedlight mode.&nbsp; Joe McNally touts FP&nbsp; flash use in bright sun, but he also uses four SB-900. <img src="http://www.nikoncafe.com/vforums/images/smilies/smile.gif" alt="" class="fr-fic fr-dii fr-draggable " style="" />&nbsp;So the range is less, but the range (of direct flash) can be&nbsp;&nbsp; calculated/predicted.&nbsp; Several of the flash manuals have Guide Number&nbsp;&nbsp; charts for FP mode.&nbsp; <a href="http://nikonites.com/products/flashes-6/sb-700-af-speedlight-86/" target="_blank">SB-700</a> manual, pages H-25, H-26, for example.&nbsp;People get excited to realize that fast shutter speed decimates FP flash&nbsp;&nbsp; power, but in regard to the shutter, they must not understand that FP&nbsp; flash&nbsp; is exactly the same&nbsp; situation as for the Sun (it is continuous&nbsp; light too).&nbsp; Twice the&nbsp; shutter speed is half the light, for both of&nbsp; them.&nbsp; Regular <a href="http://rd.bizrate.com/rd?t=http%3A%2F%2Fwww.42Photo.com%2Fpd-productid-105352-k-nikon_d3100_142_megapixel_digital_camera_body.htm&amp;mid=31456&amp;cat_id=402&amp;atom=10020&amp;prod_id=2567223546&amp;oid=4520594957&amp;pos=1&amp;b_id=18&amp;bid_type=0&amp;bamt=a5fedf14fd8fec0d&amp;cobrand=1&amp;ppr=010898e25571d931&amp;rf=af1&amp;af_assettype_id=10&amp;af_creative_id=6&amp;af_id=6784" target="_blank">speedlight</a> flash mode is not affected by shutter speed, but FP mode and the Sun are.&nbsp;We see silly charts online computing how FP power varies with shutter&nbsp;&nbsp; speed.&nbsp;&nbsp; They must not realize FP becomes continuous light, it simply&nbsp; turns&nbsp; on, and stays on, and then the shutter opens and does all of the&nbsp; timing.&nbsp;These GN charts are for ISO&nbsp; 100, and 1/500 second in FP mode. But it is&nbsp; a general purpose chart.&nbsp; The overwhelming idea we ought to&nbsp; know about&nbsp; FP mode is that it becomes continuous light now, which means Equivalent Exposures apply to it, same as like for sun light too.&nbsp; &nbsp;So, for example, the SB-700 chart (DX&nbsp; mode) says GN 43.6 for 28mm zoom&nbsp; at full power FP.&nbsp;&nbsp; So therefore, ten&nbsp; feet computes 43.6/10 = f/4.4 at&nbsp; 1/500 second. This is for full&nbsp; exposure, so fill at -1EV would be 1.414&nbsp; times this distance range. And ISO 200 would be 1.414 times this GN.&nbsp;Metering is good, it is much more simple.&nbsp; <img src="http://nikonites.com/images/smilies/smile.png" alt="" class="fr-fic fr-dii fr-draggable " style="" />&nbsp; &nbsp; &nbsp; But the chart helps us plan it out before we leave home, to know&nbsp;&nbsp; capabilities. The real point is, doubling shutter speed to 1/1000&nbsp;&nbsp; second, and also opening aperture one stop (three third clicks) to&nbsp;&nbsp; compensate, is equivalent exposure, for FP flash, and for sun too, for any continuous light.&nbsp; Meaning, the same 1/500 second Guide Number chart can be used for any&nbsp;&nbsp; faster shutter speed too (in this compensating way).&nbsp;&nbsp; Again, regular&nbsp;&nbsp; flash mode does NOT work that way.&nbsp;Going to 1/2000 second is just one more aperture stop to compensate, but&nbsp; then it is the same exposure and the same range (assuming FP flash&nbsp; mode). This is quite a lot to know.More FP at <a href="http://www.scantips.com/lights/flashbasics2b.html" target="_blank">http://www.scantips.com/lights/flashbasics2b.html</a>.</blockquote>

[QUOTE="WayneF, post: 182951, member: 12496"] The lighting does look real good. Auto FP flash mode maximum is around 1/5 power, about -2.3 stops down from regular flash mode. Five FP flashes working together would match same one flash power in regular speedlight mode. Joe McNally touts FP flash use in bright sun, but he also uses four SB-900. [IMG]http://www.nikoncafe.com/vforums/images/smilies/smile.gif[/IMG] So the range is less, but the range (of direct flash) can be calculated/predicted. Several of the flash manuals have Guide Number charts for FP mode. [URL="http://nikonites.com/products/flashes-6/sb-700-af-speedlight-86/"]SB-700[/URL] manual, pages H-25, H-26, for example. People get excited to realize that fast shutter speed decimates FP flash power, but in regard to the shutter, they must not understand that FP flash is exactly the same situation as for the Sun (it is continuous light too). Twice the shutter speed is half the light, for both of them. Regular [URL="http://rd.bizrate.com/rd?t=http%3A%2F%2Fwww.42Photo.com%2Fpd-productid-105352-k-nikon_d3100_142_megapixel_digital_camera_body.htm&mid=31456&cat_id=402&atom=10020&prod_id=2567223546&oid=4520594957&pos=1&b_id=18&bid_type=0&bamt=a5fedf14fd8fec0d&cobrand=1&ppr=010898e25571d931&rf=af1&af_assettype_id=10&af_creative_id=6&af_id=6784"]speedlight[/URL] flash mode is not affected by shutter speed, but FP mode and the Sun are. We see silly charts online computing how FP power varies with shutter speed. They must not realize FP becomes continuous light, it simply turns on, and stays on, and then the shutter opens and does all of the timing. These GN charts are for ISO 100, and 1/500 second in FP mode. But it is a general purpose chart. The overwhelming idea we ought to know about FP mode is that it becomes continuous light now, which means [B]Equivalent Exposures[/B] apply to it, same as like for sun light too. So, for example, the SB-700 chart (DX mode) says GN 43.6 for 28mm zoom at full power FP. So therefore, ten feet computes 43.6/10 = f/4.4 at 1/500 second. This is for full exposure, so fill at -1EV would be 1.414 times this distance range. And ISO 200 would be 1.414 times this GN. Metering is good, it is much more simple. [IMG]http://nikonites.com/images/smilies/smile.png[/IMG] But the chart helps us plan it out before we leave home, to know capabilities. The real point is, doubling shutter speed to 1/1000 second, and also opening aperture one stop (three third clicks) to compensate, is[B] equivalent exposure[/B], for FP flash, and for sun too, for any continuous light. Meaning, the same 1/500 second Guide Number chart can be used for any faster shutter speed too (in this compensating way). Again, regular flash mode does NOT work that way. Going to 1/2000 second is just one more aperture stop to compensate, but then it is the [B]same exposure and the same range[/B] (assuming FP flash mode). This is quite a lot to know.[COLOR=#000000] More FP at [URL]http://www.scantips.com/lights/flashbasics2b.html[/URL][/COLOR]. [/QUOTE]

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