F100 and studio strobe

[warrenlewis]

In its simplest form, if I connected a sudio flash to the F100 via a

PC connector, set the camera on shutter at 1/60th, would the camera

adjust the aperature? Is it possible to set this up with TTL? I was

given an Excalibur 1600. Any suggestion as to books or web sites

that can help me fumble my way through studio strobes would be

appreciated......Thanks, Warren

[efusco]

No

[efusco]

Sorry, pretty incomplete answer and I didn't pay attention to the last sentence.

 

Basicly, you can't use TTL metering with studio strobes (unless someone's making a module tha I'm unaware of for that purpose, but it will mean extra $$) You have to meter the light with a handheld incident meter and use manual mode on the camera for consistantly decent exposure.

 

I learned a lot about studio photography from Scott Smith's Book "Studio Lighting Made Simple"...I highly recommend it. He does discuss lights, lighting, metering, minimal equipment needs, etc... He's also highly responsive if you call or e-mail and truely seems to enjoy helping people learn the craft. His web site also contains some pretty good starter info while you're waiting for the book to ship...I have no association or financial interest in Scott or his book, just a satisfied customer.

 

www.lightingmagic.com

[hkbmac]

Buy or rent a flashmeter, and get a copy of the lighting cookbook.

 

Brian -bmacphoto

[warrenlewis]

What will the camera do as far as aperature in the original setup? If I set the camera to a specific shutter speed, it will automatically set the aperature. As a test, I just set the camera on 1/60th and moved it through an arc of varied degrees of light and dark, and the camera "knew" enough to change f-stop. Is a flash duration to short? Does connecting through the PC connector disconnect modes?

As a side, I will hit the book store tomorrow.....thanks for the info.....Warren

[jim_gifford]

Warren, when you hook up studio strobes you use the PC connection from the camera.

 

The camera won't adjust aperture to account for the light from the PC-cord flash, even if the camera is in one of the automatic exposre modes (A, S, P). In automatic exposure modes, the camera will instead adjust aperture to attempt to achieve the correct exposure without any flash... so when you add the studio strobe to the equation and still use autoexposure on your camera you get overexposure of whatever the flash is lighting.

 

That's why you want to be in manual mode, adjusting the aperture yourself so it is correct for the combination of flash and ambient light.

 

How do you know what that correct f/stop is?

 

Flash meter.

 

Voila.

 

When you read a book or two on the subject, all this should become much more clear.

 

But the short answer is, your camera doesn't work in TTL flash mode with studio strobe setups. If you want TTL flash you use a Nikon speedlight (or Nikon-compatible flash) on the hot shoe, or on an SC-17 TTL extension flash cord, or with an SU-4 TTL wireless adapter and so on.

 

You use manual exposure settings with studio flash units.

 

Have fun,

[warrenlewis]

Why does the camera not automatically adjust to the strobe, when it will adjust to other types of light?

[efusco]

Warren, you're getting some pretty good answers here and you don't seem to want to accept them. With Nikon TTL compatible strobes the flash and the camera communicate with one another, the camera controls the flash output and uses other information to determine exposure and adjusts the aperture accordingly.

 

With a NON-TTL flash such as a studio strobe that feedback loop doesn't exist. The high intesity very brief flash of light comes out of the studio strobe in a fixed quanta. There is no way the camera can read and adjust the exposure during the picture taking mode, it is too fast and the aperture is determined before the stobe actually fires.

 

Trust us, it does not work, you have to use manual mode and read your light with a hand-held light meter.

Capice'?

--evan

[warrenlewis]

Evan, Thank you for your answer. Yes, I've gotten good advice and will pick up a book or two tomorrow. Your sentence explaining that the aperature is set before the strobe fires, as well as your statement that the flash is too quick clears things......Thanks, Warren

[david_h._hartman]

TTL flash is getting feedback from light reflected off the film. There are sensors that "look" back to the film in the bottom of the mirror box of your camera. When the cameras senses enough light the camera sends a signal to the detected TTL flash to stop.

 

The PC cord only triggers the studio strobe, there is no communication other than open or close, fire or not. When the first curtain in your F100�s shutter is fully open the circuit through the PC cord is closed and the strobe fires. Your camera needs to be manually set to a shutter speed of 1/250th second or less. If it is set to a faster speed the second curtain will cover part of the frame and that part of the frame will be dark as that part will not receive light from the strobe. Buy a book, buy a flash meter, have fun.

 

Hope this helps,

[jim_gifford]

<<Why does the camera not automatically adjust to the strobe, when it will adjust to other types of light?>>

 

Other folks have given you the info, but let me try to flesh it out and put it in sequence, maybe this will help. God willing I won't screw this up somewhere...

 

1) Any adjustment the camera makes on your behalf (in A, S, P modes)for ambient light happens before the shutter opens... when you push the shutter button, the aperture is stopped down to the selected value in a fraction of a second, and of course the mirror is swung up out of the way, and then the shutter opens and shuts.

 

2) You have to use the PC cord for studio lights, and that connection is designed only to give the "start" signal to a flash. This is not an F100 limitation or a Nikon problem, it's the standard for PC cords... they are one-trick ponies. They just say "start."

 

3) The "start" signal goes out the PC cord to the flash when the shutter is opening, and as we've just noted, by that time the camera has already finished calculating its exposure so it doesn't know about the flash contribution that is about to hit your subject.

 

4) TTL flash is different because the adjustment the camera makes for TTL flash happens through the multiple contacts on the hot shoe... so the camera can tell a TTL flash two things: when to start and when to quit. It does this with meter technology that reads the collected light from the flash off the film during the exposure itself (this is separate from the meter technology that determines your ambient light exposure). More magic that happens through the contacts in the hot shoe: the flash also tells the camera when it is powered on, and when it is fully charged and ready for action. The hot shoe is the source of the signals that tell the camera to be ready to use the TTL flash metering magic during a given exposure.

 

4a) Nikon bodies with built-in TTL speedlights conduct a similar conversation internally for the built-in, pop-up unit and also can speak through the hot shoe to an accessory flash.

 

4b) Your F100 doesn't have a built-in flash, so it handles TTL through the hot shoe exclusively. If you use an SC-17 extension cord you're just relocating that hot shoe, as far as the camera is concerned. If you use an SU-4 wireless unit, it essentially becomes a remote copycat of the accessory flash in your hot shoe, firing when that flash does and extinguishing when that flash does. So your camera still just knows about the flash hooked to its hot shoe, but the meter reads the light from two, three or forty flash units and when it feels "enough is enough," it tells the unit on its hot shoe to quit, and the wireless gizmos react instantly to shut themselves off also. Magic juju.

 

5) The F100 cannot work that magic juju with the PC cord because the industry-standard PC cord system is a one-way, one-signal deal. The camera doesn't have a clue whether a flash at the far end of the PC cord is on or off, charged or exhausted... it doesn't even know whether there is a flash at the other end of the PC cord at all. So it doesn't know that it should be ready to use its TTL flash metering during the exposure. It just sends a few electrons down the pipe to its PC contact whenever the shutter trips. That'll trigger a flash you hook to the PC connector.

 

Okay, now enjoy the book(s) on how to use studio flash to your advantage. And have fun selecting a flash meter (plenty of threads on that in the photo.net archives).

 

Good luck,

[warrenlewis]

Jim and all, Thanks.....Warren

[hal_bissinger]

Warren, it's really very simple. With a Nikon dedicated flash on your camera hotshoe, the flash actually becomes part of the camera. Both the flash and the camera communicate back and forth in the instant before the picture is taken to automatically get the exposure right. The flash knows how bright it needs to be and when to shut off because the camera tells it things like the film speed you are using, aperture, and how far away you are from your subject. The flash will actually fire off some "preflashes" before the shutter opens to kind of get a feel for what it has to do. <p>

This is not the case with a "dumb" studio strobe. All it knows how to do is fire. You have to adjust it to how bright you want it. The camera never even knows it is there because the sync cord does nothing more than the wire to a door bell button does, with the camera being the button. Push it and the strobe fires... thats it! <p>The camera can't "see" the light from the strobe and meter off of it because the strobe fires, obviously, when the shutter opens... but at this time remember that the mirror flips up blacking out the viewfinder and preventing any light from reaching the metering sensors.<p>

Basically, the way you work with studio strobes then is usually you decide on what aperture you want to shoot at and adjust your lighting accordingly to give you that much light. You put your camera in manual mode and choose a shutter speed at or below the maximum sync speed for your camera which is 1/250. You probably won't believe that the shutter speed doesn't make any difference here as long as it's below the maximum sync speed, but for now just accept it and be happy you won't have to worry about it. Now, if say you set your aperture at f/11, you adjust your lighting until it gives you f/11 in front of your subject as read on the flash meter.<p>

That's basically it. Some reading up on the subject of studio lighting and lots of practice will give you most of what you will need to know.

[k_michael]

Warren, take a good lighting course and you'll learn all about ambient, hot lights and flash. I didn't read the whole thread, but I think you're under the idea that studio flash works the same way as hotlights or ambient do.