X2D flash Sync problem

[billmcdad]

I must express my profound adoration for the X2D and the sheer pleasure I derive from using it, especially now that I have the 90mm f/2.5 . However, I have a minor issue when using my Profoto flash. It appears that when my shutter speed surpasses the 1200 mark, my images are way underexposed. I know this issue stems not from the camera or lens but rather from the flash duration. Have you ever encountered a similar challenge using your X2D? I would be grateful for your assistance if you have any insights or remedies.

[mar-ko]

Which Profoto flash are you using?

Battery powered flashes are often no "high speed kings".
A Profoto B10, for example, fired in "normal" mode at 125 W (display reading "9.0") will need 1/660 sec. to emit 90% of the light.*)

So, if your camera is set to 1/1200 sec., the camera will have finished the exposure, while the flash is still emitting light—resulting in an underexposed image.

Unfortunately, flash speeds are often only given for t0.5 ("half of the light is emitted") and often only for low power settings (which are much faster than flashing at full power), so you will often need to *measure* flash duration when using fast sync speeds, which only a few light meters can do.


*) B10 /w firmware A6, measured with Sekonic L-858D, duration measuring mode "t0.1"

[Conner999]

You need to scour specs and find a flash/pack with t0.1 durations of >= 1/1200 sec in the range of power levels you typically need. A lot of the newer light developments focused more on adding TTL , etc., then short durations, but they are out there.

You can also use multiple lower-power units with fast durations at lower power levels than you need (most durations get longer as power increases) and using a bracket, etc.,  have multiple units fire together to get the duration+power you need. Many Godox and Bron units will display the t0.1 durations at each power setting which makes setting them up easier.

With the X series you're not getting TTL unless you use Nikon TTL equipped Profoto gear, but if you don't need TTL, some older lights were very, very quick such as the Elinchrom Quadra w/Action heads, some Bron units, the 1200Ws Profoto Pro B2/B3s, etc.

[Juansphotos]

I tested this with my Godox strobes and could not get solid power past 1/750 shutter speed. The indicated t.01 flash durations even at lower power were too slow. I found that I needed a duration double the shutter speed once I went over 1/500 shutter.  I need to test on my AD1200 though. More power "should" mean faster durations through the range. This definitely is not a camera issue as my Leica Q3 had the same results at higher shutter speeds.

On a side note. I started using the Stellapro Reflex S recently and have been pleased with its output so far. I was able to get a nicely lit image at 1/500, 5.6 and ISO 200. Normally with an LED with "digital burst" this wouldn't be possible.

[ashdown]

Sync speeds are what brought me to Hasselblad a decade ago and I have done quite a lot of experimenting. As has been said, many flash systems have a fairly slow complete duration at higher power levels and it can take some digging to find out the actual figures. Some Broncolor and Elinchrom systems use a technology that means the duration gets shorter as the power is increased whereas most systems use the duration to control the output w/s. The faster method uses big capacitors to do the work so is restricted to pack systems so I don't think you will find a really fast (full power) duration on anything compact and portable.

The other variable is the trigger. Some triggers are faster than others. Some have a 'speed' mode on both trigger and receiver. A sync cable is probably fastest of all.

I use Elinchrom Ranger RX Speed packs with the Action heads along with their own Skyport triggers set to speed mode. The 1100w/s full power output is just starting to get cut off at !/2000th. I'd be very impressed if there is a flash system that can manage full power flash within a 1/4000th shutter release.

[Conner999]

As was stated above, the t0.1 duration displayed on a light/ pack is as if you pushed the test button. It doesn't factor in the propagation delay of a radio trigger.

Some triggers like the Elinchrom units have a speed mode (as I think does Profoto IIRC). This mode keeps constant contact between the trigger and receiver and drains their batteries faster, but does work well.

If really fast durations are needed, either a cable or a speed trigger/receiver to trip the light and a proprietary trigger in your pocket or elsewhere on the camera to adjust power. TTL is then out of the question, but...

[JCM-Photos]

Yes Elinchrom triggers have normal mode and speed mode and they say clearly that speed mode is for leaf shutters.

The restriction with speed mode is a drastically reduction in reach, but it remains plenty enough for a big studio, even if it will no more fire at 50m like normal mode does.