DSLR's with fibre optic cables

[pooley 39]

I've seen some good deals on some DSLR housings that feature fibre optic flash connectors. However, does anybody know if this method is used will there be a significant shutter lag similar to using a compact? If they do, I might as well save the money and stick with the little fellas!!

[rtrski 20]

Fiberoptic is used to feed the external strobes in a 'slave' mode, primed by the internal strobe. Light is, well, kinda fast, even thru fiberoptics vs. vacuum.

 

There is no reason to believe this method of activating strobes introduces any shooting delay of any kind. In fact, the camera doesn't even "know" that there are external flashes in most cases, it just triggers its flash and gets considerably more.

Edited November 1, 2009 by rtrski

[Gudge 58]

........ does anybody know if this method is used will there be a significant shutter lag similar to using a compact?

I converted by rig from electric to fibre optic sync cords and can confirm that there is no difference betweent the two shutter lag wise.

[pooley 39]

Cheers guys, maybe its just me being dim (or being used to using film...), I was just concerned that pre-flashes would slow things down.

Am I just being dim?

 

Be honest with me!...

[ce4jesus 1]

Okay..you're being dim Camera's and/or strobes are going to "preflash" regardless of the connection. The camera sends out an invisible pulse of light. When this light bounces back to the camera off the subject. The camera then uses that information to set your strobe output. In the case of fiber optic strobes like Inon, they use their own preflash signal. In the case of a physical cable, the strobe just reads what the camera tells it and fires accordingly.

 

In the case of a point and shoot there are several things that affect shutter lag and its ability to shoot again after firing. Both are bothersome. First the camera's focus speed is usually very slow, especially in low light, compared to even the most entry level DSLR. Secondly if your subject is moving the P&S tend to hunt more. A DSLR will have a much faster lock and ability to fire. Finally P*S take forever to recharge a full dump of the internal strobe. They also take a few seconds to record to even the fastest of cards. Add those things together along with a small battery it leads to wait times between photos. A DSLR equipped with high end strobes can fire a full dump every second or so. It simply means you're ready to fire almost instantaneously. The final nail in the coffin is glass. DSLR glass is superior to any PS. If you're serious about not missing something, then its the way to go.

[tdpriest 115]

It's fast (do you notice the preflash in terrestrial strobe photography?), but...

 

... some housing/port combinations allow light to reflect off the inside of the port, producing a "ghost" image of the lens.

 

This is worst with big domes and fisheye lenses, and, as far as I can tell, absent from macro lenses and flat ports. I use home-made circular baffles that fit around the base of the lens and block the gap between the lens and the port ring. I've noticed that some more recent housings have been designed to block light travelling downwards from the camera's internal flash.

 

My other gripe is that I can't disable the internal flash when it's in the housing, so it fires when the wet strobes are turned off, and, of course, fires at full power.

 

Tim

 

Edited November 3, 2009 by tdpriest

[Gudge 58]

... some housing/port combinations allow light to reflect off the inside of the port, producing a "ghost" image of the lens.

 

This is worst with big domes and fisheye lenses, and, as far as I can tell, absent from macro lenses and flat ports. I use home-made circular baffles that fit around the base of the lens and block the gap between the lens and the port ring. I've noticed that some more recent housings have been designed to block light travelling downwards from the camera's internal flash.

My conversion kit from Reef Photo & Video came with a foam ring that fits around the lens and blocks off the port to prevent this. It should be easy to make one up as a DIY project:

 

 

My other gripe is that I can't disable the internal flash when it's in the housing, so it fires when the wet strobes are turned off, and, of course, fires at full power.

Some housings (eg my wife's 400D Seatool housing) have a control that allows you to close the camera's internal flash when you don't want to use your strobes. To get the flash back up again all you do is put the camera in full auto mode and press the shutter release and it pops up automatically (as long as you're pointing the camera at something dark). Edited November 3, 2009 by Gudge

[Alex_Mustard 0]

The Zillion housings have flash up and down controls. Alex

[davelew 4]

My other gripe is that I can't disable the internal flash when it's in the housing, so it fires when the wet strobes are turned off, and, of course, fires at full power.

 

I'm not familiar with the Nikon D200 menus, but my Nikon D90 lets me set the power of the onboard flash to 1/128 normal power through some menu selections. It requires a few key presses, fourteen if I remember correctly (menu, ok, down arrow five times, ok, down arrow, right arrow, ok, left arrow, ok) but it doesn't take that long to do, even with gloves on.

[Gudge 58]

My other gripe is that I can't disable the internal flash when it's in the housing, so it fires when the wet strobes are turned off, and, of course, fires at full power.

I was thinking about this last night before I dropped off to sleep and came up with a solution. On my 40D & 50D it is possible to disable the internal flash from the menu system. I just tried this after I had raised the flash on my 50D and the camera operates just as if the internal flash wasn't raised (ie max shutter speed no longer limited to maximum of 1/250 for flash sync) and the flash won't fire. Enabling the flash again limits sync speed to 1/250 again and flash fires. I'm not that familiar with Nikon dSLRs but I'm sure that they would have a similar feature.