Jump to content


Member Since 07 Nov 2004
Offline Last Active Today, 07:08 AM

Posts I've Made

In Topic: Strobes intermittently firing

19 October 2016 - 10:37 PM

FYI - Inon strobes are designed to use S&S cables. I have found S&S cables to be reliable. It sounds like your strobes were not able to charge up the capacitors. The light comes on when they are charged. This could be due to a weak battery. Are your batteries OK? The circuitry responsible could be bad as well. I would do your tests with fully charged Eneloops. If you suspect the sync cable - test one strobe at a time with a singleton sync cable. Keep things as simple as possible to do a process of elimination.


You said "I am now wondering if this may be related to using sea&sea cables with a Inon strobe,"


In Topic: Canon 1dx and 1dx II idenitcal bodies? Can I keep my old Canon 1dx housing?

18 October 2016 - 11:24 PM

I have both cameras as well as a Seacam 1Dx housing. I removed the internal contact parts of the 3 controls on the back that have changed and was able to fit the 1Dx2 into the housing and also able to dry fire it (i.e. indoors). I do not recall absolutely if I plugged in the flash synch do-dad (the gizmo that slides into the hot-shoe) or not as it was several months ago. I am waiting to see what is different about the new Seacam housing - probably will be shown at DEMA as it may be out already.

In Topic: blurry fish shutter speed advice

16 September 2016 - 11:13 AM

I don't understand. If you use aperture priority, how do you also set the shutter speed? Doesn't the camera just pick one to give you the correct exposure?

Roger that. The camera selected the 1/640 s. It also varied the ISO since I was using auto ISO - I use this a lot for ambient light pix. I set 1/500 s. as the minimum shutter speed and ISO 800 and 12800 as the, respectively, minimum and maximum ISO (in the auto ISO menu). Fixed at f/13 due to aperture priority. This is with a 1Dx, auto ISO functionality varies with camera model. If I run out of ISO, i.e. at 12800 and more exposure is needed then the camera will go to longer than 1/500 s. (this happens later in the day as well as when a cloud passes between the sun and the camera - the sun is weaker in Alaska at 60 degrees N compared to the tropics- so exposures may be different from you are used to).

In Topic: blurry fish shutter speed advice

16 September 2016 - 10:21 AM

Please post examples, can't really help without.  1/250 should be more than enough to freeze the action so seems a bit strange to be honest


Some fish are capable of very quick movement that may not involve traveling. Family Antennaridae feeding comes to mind.


I was editing pix I took a few weeks ago yesterday and marked this one to use here in case this got asked. This is an ambient light exposure at 1/640 s. I was using aperture priority with auto ISO. Note the blur at the front and tail ends of this female Pink Salmon in the process of excavating her redd. The large dorsal spots just posterior of her head are not blurred. Rocks on the bottom closer than the fish are in focus so this is not a DOF issue. One pic is a blow-up of the other.

In Topic: blurry fish shutter speed advice

15 September 2016 - 02:42 PM

1/1000 s for a strobe duration is really long.....10 times shorter than that is more likely. Any blur is almost certainly due to ambient light and camera settings that allow that ambient light to get to the sensor. Use small apertures, low ISO, strobes on high power, and avoid any camera automatic exposure settings like P or A or S.

I don't think so.

To get to near 1/10000 of a second one has to turn down the power. For example-

This site has some actual measurements:



The first strobe listed is a Canon 580EX

At full power the duration is just 1/250 s.

At half power it is close to 1/1000 s.

To get to near 1/10000 s. one has to go to 1/32 power.

Other strobes are not as quick.

Both Broncolors had longer than 1/1000 s. duration at all settings tested.

It would be cool if we had data like this for underwater strobes!

I typically use my underwater strobes at 1/2 to 1/4 power so I expect the flash to be closer to 1/1000 s. rather than 1/10000 s.