IQ3 100 + ES + Strobe???

[Chris Barrett]

Ok, so what's the deal with the electronic shutter and strobe?  From what I've read, it appears that you can only sync strobe at something like 1.3 seconds and longer exposures???  If that's true, it makes the combo unusable for daylight interiors.  I'm always exposing somewhere between 1/8th and 1/2 second.  I get that the ES employs a rolling shutter, but flash duration is less than a 5ooth, so It's not like the shutter can slowly expose the strobe over that 1.3 sec.

What gives?  ES makes this back attractive to us Arch shooters, but not if we can't use strobe.

-CB

[DrakeJ]

Ok, so what's the deal with the electronic shutter and strobe?  From what I've read, it appears that you can only sync strobe at something like 1.3 seconds and longer exposures???  If that's true, it makes the combo unusable for daylight interiors.  I'm always exposing somewhere between 1/8th and 1/2 second.  I get that the ES employs a rolling shutter, but flash duration is less than a 5ooth, so It's not like the shutter can slowly expose the strobe over that 1.3 sec.

What gives?  ES makes this back attractive to us Arch shooters, but not if we can't use strobe.

-CB

So an electric shutter reads line per line off the sensor, in this case for 1.3 secs. Imagine a strobe firing when the sensor readout begins, only a fraction of the sensor will be read at that moment.

To summarise, use continuous lighting with ES.

[Chris Barrett]

Right, I get that... but then why is it ok to use strobe and ES with longer exposures?

[william]

I'm not an architectural shooter, so take this with a grain of salt, but:

Wouldn't the combination of mirror up plus vibration detection delay plus leaf shutter plus remote triggering via the app get you 99% of the way there in terms of minimizing image shake?

[douglevy]

Chris - you probably have to use rear sync with longer exposures.

[ErikKaffehr]

Hi Chris,

Strobes are usable as soon the shutter is fully open during any part of the exposure. As long as exposure is shorter than curtain travel time it will always be partial, thus not usable with flash.

Mostly, EFCS is the ideal solution. It is based on a sweeping reset, that can be made extremely fast and a second mechanical shutter that stops exposure and allows for a slow readout. The sweeping reset is totally vibration free and most of the vibration caused by the second shutter affects the camera after the exposure. The last part here is a bit oversimplified, I think…

ES also uses a sweeping reset, followed by a sweeping readout. But, sweeping readout cannot be made very fast. So ES is limited by readout speed.

Best regards
Erik

Right, I get that... but then why is it ok to use strobe and ES with longer exposures?

[Paul2660]

The IQ100 also has electronic first curtain. This feature was actually there prior to the ES. But unlike ES which can be turned on by the user EFC was only used in certain modes like when the seismic sensor was in use. I tried to find more about the EFC on the P1 site but was not able to find much.

Dealers may have more info.

Paul Caldwell

[Wayne Fox]

Right, I get that... but then why is it ok to use strobe and ES with longer exposures?

basically the ES is working like a very slow focal plane shutter ... it takes .65 seconds for the first curtain to open, then another .65 seconds for the curtain to close.  So the flash must fire when the first curtain is open and before the second curtain is closed just like with mechanical focal plane shutters(which open and close in 1/250th of a second or faster).

Note that 1.3 seconds applies for ISO's over 400, if you use lower ISO's it's 1.6 seconds.

The big advantage to me of ES is on a tech camera so I don't have to use the cameras own shutter to take a shot. I trigger the exposure using Capture Pilot on my iPhone (sometimes I'm not even near the camera).  Using Live View and Capture Pilot I'm finding myself using camera angle I've never used before (tripod fully extended so I can barely reach the controls on my Cube to adjust composition).

  I assume if on a tech the flash can be triggered from the port on the digital back so it sync's correctly.  Electronic first curtain is awesome though, and insures virtually vibration free shots.  Might also work well for you and allow you to use shorter times to help correctly mix strobe and available light.