v1.0.2 software for 645D

tuco · 03-15-2011, 02:34 PM

Originally posted by Shuttershane

I was wondering the same thing.

1/125 is not great, but its not terrible (I do not miss the days of 1/60). Maybe he likes to shoot wide open?

The difference between the modeling lamps in my Alianbee strobes and flash burst is much more than 5 stops plus they shut off prior to the flash automatically. I have LS lenses and even though I can select up to 1/500 flash sync, I pick 1/125 and still get an effective shutter speed of 1/2000 at full power, t=0.1 (1/6000 at t=0.5). I really don't see the need for faster shutter unless there is a lot of ambient light that I can't control. I guess there can always be that case though.

Shuttershane · 03-15-2011, 03:12 PM

What do you mean by effective shutter speed?

tuco · 03-15-2011, 03:23 PM

Originally posted by Shuttershane

What do you mean by effective shutter speed?

The speed of the flash. If the ambient light is low enough as to not be recorded in that 1/125th of a second or not significant enough to contribute to the exposure, it is the duration of the key and fill flash that becomes your "shutter speed".

Warped · 03-16-2011, 12:14 AM

Originally posted by tuco

Is the ambient light in your studio so strong that you need a higher snyc?

Is the Bowens 500 a Gemini 500c/500r or Pro?

I don't have my own studio and the ambient light in the studios I hire varies quite a lot.

I've seen some very cool stuff done outdoors using high sync speeds and fast shutters to control the ambient daylight and flash/strobe lighting as the main key lights.

I certainly don't "need" a faster sync (if I did I wouldn't ahve forked out $10K+ for the 645D!!), would just be nice to have the option to play around a bit more and do that easily.

Checked the specs of the 500 Gemini and the flash duration is 1/925 - so shouldn't be an issue using those lights and going faster than the 1/250th I've used so far with my cheat.

HawaiianOnline · 03-16-2011, 01:40 AM

Originally posted by Shuttershane

Really! That's awesome news. I will start looking for these lenses. Thanks

The 75mm LS allows for 1/500 sync, IIRC.

03-15-2011, 03:23 PM	#18
tuco Pentaxian Join Date: Jul 2009 Location: Pugetopolis Posts: 11,026	Originally posted by Shuttershane What do you mean by effective shutter speed? The speed of the flash. If the ambient light is low enough as to not be recorded in that 1/125th of a second or not significant enough to contribute to the exposure, it is the duration of the key and fill flash that becomes your "shutter speed". Last edited by tuco; 03-15-2011 at 04:38 PM.

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03-15-2011, 02:34 PM	#16
tuco Pentaxian Join Date: Jul 2009 Location: Pugetopolis Posts: 11,026	Originally posted by Shuttershane I was wondering the same thing. 1/125 is not great, but its not terrible (I do not miss the days of 1/60). Maybe he likes to shoot wide open? The difference between the modeling lamps in my Alianbee strobes and flash burst is much more than 5 stops plus they shut off prior to the flash automatically. I have LS lenses and even though I can select up to 1/500 flash sync, I pick 1/125 and still get an effective shutter speed of 1/2000 at full power, t=0.1 (1/6000 at t=0.5). I really don't see the need for faster shutter unless there is a lot of ambient light that I can't control. I guess there can always be that case though.

03-15-2011, 03:12 PM	#17
Shuttershane Senior Member Join Date: Dec 2010 Photos: Gallery Posts: 164	What do you mean by effective shutter speed?

03-16-2011, 12:14 AM	#19
Warped Veteran Member Join Date: Oct 2008 Photos: Gallery Posts: 351	Originally posted by tuco Is the ambient light in your studio so strong that you need a higher snyc? Is the Bowens 500 a Gemini 500c/500r or Pro? I don't have my own studio and the ambient light in the studios I hire varies quite a lot. I've seen some very cool stuff done outdoors using high sync speeds and fast shutters to control the ambient daylight and flash/strobe lighting as the main key lights. I certainly don't "need" a faster sync (if I did I wouldn't ahve forked out $10K+ for the 645D!!), would just be nice to have the option to play around a bit more and do that easily. Checked the specs of the 500 Gemini and the flash duration is 1/925 - so shouldn't be an issue using those lights and going faster than the 1/250th I've used so far with my cheat.

03-16-2011, 01:40 AM	#20
HawaiianOnline Veteran Member Join Date: Jan 2007 Location: Hawaii Posts: 613	Originally posted by Shuttershane Really! That's awesome news. I will start looking for these lenses. Thanks The 75mm LS allows for 1/500 sync, IIRC.