What Shutter Speed to Use?

[Max Power]

Hello all,

I have just started to dip my toe into MF and I recently acquired a Mamiya C220. It is spectacular!

Yesterday I went out and bought a hotshoe/pc synch for it so I can start to play around with the flash. I read the section on 'Flash Photography' in the Kodak Professional Photoguide, and I understand everything written about GNs and BCPS and how to calculate f-stops with distance etc etc. There is one thing, however, which confuses me: what shutter speed do I use as a baseline?

I know that leaf-shutters x-synch at all speeds with electronic flash, and thanks to all of you, I understand why. But still, there must be some starting point! Even the Kodak Pro Guide's Flash Exposure Dial talks about shutter speed compensation factors to use depending on the ambient conditions...Great! But where do I start? Should I use 1/60 as with a focal-plane SLR?

Can someone help me with this?

Cheers,
Kent

 

[Donald Miller]

The shutter speed that one uses will be dependent on how you want flash to balance with existing light. In other words by shooting at a higher shutter speed you could make an otherwise lit background go completely black or by shooting at a slower speed the other effect could be obtained.

So shoot at whatever speed you want to give the effect that you want.

 

[David A. Goldfarb]

Run a test roll and see for yourself. Set up a portrait or still life subject with whatever you consider a "normal" amount of ambient light (room lights on? modeling lights on?). Shoot a series of frames on each shutter speed from fastest to slowest. Print a contact sheet, and note when you start to notice the ambient light having an effect, and if it's a portrait subject, when you might notice ghosting from the ambient light.

Depending on how powerful your strobes are and how much ambient light you have, you might not notice any effect from ambient light until you get to about 1/15 sec. or even longer. I've used open flash technique with powerful strobes and dim light, where my human-sync speed (how long it takes to uncover the lens, fire the strobes, and cover the lens by hand) can be around 1/2 to 1 sec.

 

[Nick Zentena]

Well you can use whatever you want that gives the right exposure you want. Find out just how long your flash will flash at full power. My Metz is 1/300 at full power. If I use 1/400 the shutter speed is shorter then the flash duration. Not good.

1) For fill flash outdoors meter the scene and use that F/stop and shutter speed. Just set the flash head at one or two f/stops wider.

2) Indoors if you want no ambient light then use a faster speed.

3) If you want more ambient then use a slower one. Or if you want the flash to light the foreground and the ambeinet the background then meter the background shutter speed.


If you basically just want to use the flash indoors then set it at something slower/equal to your max flash duration.

Hopefully I didn't make too many mistakes.

 

[rbarker]

As others have said, "it depends".

The basic concept behind balancing the flash with the ambient light by juggling the f-stop and shutter speed is fairly straightforward once one grasps the idea that shutter speed has little or no effect on the flash contribution to the total exposure. From there, it's really a matter of style, personal preference, and the nature of the ambient light, I think.

Personally, I think it's best to make fill flash as subtle as possible, so it's not obvious that a flash was used. In some ambient-lighting situations, the "right" balance might be a half-stop down on the flash compared to the ambient level, but in others, as much as two stops down. Absent TTL-flash circuitry in the camera, as with your Mamiya C-220, the balance has to be figured manually, of course. Personal experimentation is really the only way to arrive at what pleases you most, I think.

 

[jd callow]

Two items to consider that are not completely covered are:
Sharpness due to shutter speed and lighting control.

Follow David's advice and test w/ a fair amount of ambient light and test at different speeds with corresponding aperture adjustments and you will notice your DOF will change. As the exposure gets longer the flash will be less prominent -- this may or may not be a good thing, but it is an important thing to consider.

Use this technique on people and you will loose sharpness from their inadvertent movement as the exposures get longer.

Even if you are using a tripod, a passing car, shuffling your feet (or if you live in house like mine) passing train or strong breeze can cause camera shake.

If you set your lights up and test in total darkness the spread of light with the modeling lights and shoot the subject with only the strobes you can have more complete control of the lighting.

On the flip side you can use the strobes as fills for ambient light and shoot as the conditions warrant.

I'm not sure that knowing the 'best' shutter speed is as important as knowing how to achieving the desired effects within the known usable extremes ( between 1/300 for a strobe like Nick's and somewhere around 1/8 -1/30 when shooting people at an aperture that will give you the best DOF).

FWIW I know a fashion and product photographer that swears that the faster the shutter speed the sharper the image. He uses MF equipment with in shutter lenses (max speed would be ~1/500 or maybe 1/1000 -- no good for the Nick's Metz). I am not sure what he knows to justify his argument, but there you have it - my 2c and an unknown somebody.

 

[Max Power]

I want to thank you all for your responses; they have all helped in my understanding of how I ought to be approaching the subject.

Obviously, the best thing for me to do is start experimenting with a flash in order to get a feel for how and when to use it.

Thanks,
Kent

 

[Bob Carnie]

Kent

a method that provides very neat results is to drag shutter and pop flash ,to freeze subject but still get great shawdow detail and blur.
try setting the apeture for a certain distance to flash balance. say at 10 ft your f8.
Measure the background and it may be F8 at 1/4 second.

Set your apeture at f8 and then set your shutter for 1/4 second.
When your subject moves into the 10 ft sweet spot , fire off your camera.

The flash will take care of the subject that is in the 10 ft range and your shutter will compansate for the ambient lighting .
this technique is good with a tripod.
have fun

 

[Max Power]

So here's what I did...

I set up a 'still life' in a corner with a large piece of cardboard, an off-white chair and a pillow with bold stripes of varying colours. I put in a small floor lamp with a 60watt bulb. My objective was to simulate 'normal' interior lighting conditions under which one usually uses flash. I also placed in the frame a variety of tones and textures to help in identifying the best shutter speed for each aperture. I then used the dial in the Kodak Pro Guide and determined that at 11ft I ought to use f8.

I did a series of flash exposures at f11, f8 and f5.6 for each of 1/30, 1/60, 1/125 and 1/250.

If I understand the advice that you all gave me this is an appropriate approach to the question. I will develop the roll this evening to see the results.

Can anyone offer any further opinons or points?

Thanks,
Kent

 

[David A. Goldfarb]

So if I'm understanding correctly, you did one series of four exposures at f:11, four at f:8, and four at 5.6. My suspicion is that you will discover that all four exposures at f:11 will be essentially identical, as will all four at f:8, and all four at 5.6. Ambient light at this strength will make no significant contribution to the exposure at 1/30 sec. with this amount of flash power.

If the flash exposure for your flash unit is f:8 at the chosen distance and film speed (based on the guide number, I assume), then I would do a series all at f:8 from the fastest speed to the slowest speed on your shutter. Look at the contact sheet, and note at what shutter speed you can detect a difference in the exposure based on the contribution of the ambient light.

In average room lighting, an ambient exposure with no flash at EI 400 should be around 1/30 sec. at f:2.0, so if you're shooting at EI 100, that would be 1/8 sec. at f:2.0 or 2 sec. at f:8 (plus reciprocity, if you're using a traditional film). Under these conditions, you will probably not notice any significant contribution from ambient light until you're at around 1/2 sec.

 

[gr82bart]

Kent,

Exactly what kind of flash are you using? Brand, model number? Just curious, so I can ad my two cents worth.

Art.

 

[Ed Sukach]

The "doing" of fill-in flash is easier than the explanation. I'll try..

Separate the subject from the background, and take an exposure meter reading of both. If the background averages out at X exposure, and the subject reads that it needs considerably more than that, the ratio may be too great to obtain a working compromise. Expose for the background, and the subject will be excessively "dark"; expose for the subject, and you will blow out the background (common to backlighting); Set the exposure in the middle of the two, and the subject may be BOTH excessively dark AND the background will be "blown." It may be a good idea to "fill" the subject with light and reduce the difference between the two .. say to make the subject a half stop to a full stop darker than the background. One would meter the background, set the aperture and shutter speed accordingly; and set the flash unit to provide one-half - or so less light than indicated for a full exposure to the subject. That would be known as a "one-half stop fill."

Now ... every flash unit has a flash duration time. Usually an electronic flash duration is *very* short ... and the shortest times will be encountered at reduced power rather than at full blast. My Dynalites, for example, have a flash duration of 1/450th of a second at full power, deceasing to something like 1/10,000th second at minimum power. If the shutter speed is slower than the flash duration, some light will not get to the film. Not a disaster, but a consideration when determining exposure - that is why "Flash Meters" have a shutter speed setting - they will measure the amount of light received through a give "time window".

I've read through this five times. Hopefully it will make sense to someone else ..

 

[Max Power]

OK! An update,

David, what you said would happen is what happened! All of the exposures at f8, regardless of shutter speed from 1/30 through to 1/250 are 'just right'. All at f11 are slightly under-exposed and all at f5.8 are slightly over exposed. What I get from this is that it is that when using manual flash, aperture guides the exposure, and that shutter speed (unless it is slower or faster than the flash) plays a lesser role.

Art, I'm using the Minolta 280PX which I bought as my first flash unit for my X700. I know that it's not the greatest, but it was bought to go with the x700, and works really well with that camera. It only has two settings for the GNs and so in manual, I have to match the camera's aperture to the distance scale.

FWIW, I am learning a great deal here. As strange as it may sound, using a C220 with a hand-held light meter is really driving home the thought processes necessary to producing a technically decent photograph. I find the whole process of spending a lot of time over one frame very calming and a lot of fun. Compared to 35mm my number of frames is down, but the learning curve is really steep!!!

Thanks again for your continued input everyone!

 

[Nick Zentena]

Keep an eye out for an used auto flash. It'll make your life easier. Many aren't very expensive used.

If you want real cheap then look for the Agfatronic 383cs. It's got auto mode and TTL with Metz modules. I bought one for less then $20 US. 38 metres for the guide number. Built in wide angle reflector. Second smaller flash on the head. Only uses 4 AA batteries. Nobody else seems to want the things.

 

[Max Power]

Keep an eye out for an used auto flash. It'll make your life easier. Many aren't very expensive used.

Nick,
What exactly should a good auto flash do? What should I be looking for? What brands represent a good deal?

Thanks,
Kent

 

[Doug Bennett]

Vivitar 283s and 285s are IMHO the gold standard for an inexpensive, rugged auto flash. You should be able to pick up used ones all day, and a new 285 can be had for around $100.00.

An auto flash will give you typically 3 or 4 settings, varying based on depth of field, and will tell you what f-stop to use for a certain setting. The 285 also gives you full, 1/2, 1/4, and 1/16 power settings.

Let's say that your auto flash indicates an f-stop of f8. Now let's say that you meter for ambient light and get a reading of f8 @ 1/125. Set your shutter speed to 1/125. Set your aperture to f11 instead of f8. That's a 1-stop underexposure for flash and a 1-stop underexposure for ambient. This is, in my experience, a good place to start. If, for example, you change your shutter speed to 1/250, you're still underexposing the flash by 1 stop, but now underexposing ambient by 2 stops.

This is the beauty of leaf shutters: your fill flash possibilities are so much greater. I was shooting this weekend with my Canon AE-1 and wanted to use fill flash on a shot. However, with 400 speed film, and limited to 1/60 shutter speed, I couldn't make it work. With a leaf shutter camera, it would have been a breeze.

 

[Konical]

Good Morning, Max,

Ditto what Doug says about the Vivitars. I have four 285's which have always been tough, reliable, and accurate in their auto settings.

Konical

 

[Nick Zentena]

Nick,
What exactly should a good auto flash do? What should I be looking for? What brands represent a good deal?

Thanks,
Kent

Some of it depends on how you'll be using it. If you intend to use it with other cameras.

1) A wide range of F/stops. You can fool a little with the film speed to get around this but it'll slow you down. Easier to set F/11 when you want F/11 then to change the film speed and tell the flash you're using F/8.

2) moveable head.

3) Fast enough recycle time for your needs. This will depend on what you're doing. A wedding guy is going to need a lot of flashes fairly quickly. Other less. If you need a lot of flashes then it might help if you got a flash with easy quick battery changes.


4) A good autosensor.

It's nice if it's still reasonably supported but if it's cheap enough like my Agfas then it doesn't really matter.

In todays market I've bought a pair of Metz 45 for very little. The CL-3 was about $50US. I think I paid $80 Canadian for the CT-3. They have brackets. I think you're using a TLR so the bracket might be a plus for you. They take Metz 300 and 3000 modules so you can even use them with modern cameras by just adding the right cable and module. Or you can use just the basic sync cable with your TLR. I'd avoid the CT-5 because it needs a no longer available module. I'd also avoid the CT/CL -1. These don't provide TTL etc but they don't cost much less on the used market.

 

[MikeGates]

Okay...now I'm confused. ) I'm just *now* setting up studio lighs, and planning on using my trusty ol' Nikon F2. In the dark ages, when I first bought my camera, I would hook up a strobe unit, and set my camera at the red mark just between 1/60th of a second and 1/125, and set my aperature at whatever it was that was marked on my strobe for distance.

Of course *now* I'm setting up studio strobes (White Lightning strobes--I don't recall the output as of this moment--they're at the studio space I've rented), and was planning on using the same speed (I'm guessing that would be 1/100), and using a flash meter to tell me what aperature I should use. Am I wrong? Should I be going for a faster or slower speed? I'd appreciate any help before I load up a bunch of film and start making a bunch of mistakes. I don't worry too much about using up a lot of film and chemistry while learning, but I just hate the thought of using up the time of my subjects while I grope my way through these first steps learning to use my studio lights....

Mike in Alaska

 

[David A. Goldfarb]

Mike, you've got the right idea. If you're shooting an SLR with a focal plane shutter and any strobes--on camera or studio strobes--just set it at X-sync and control exposure by adjusting flash power, distance between flash and subject, and aperture.

Once you've gotten yourself oriented, you can think about using slow sync indoors (or high speed sync outdoors, but not with an F2!) to mix ambient and strobes, but for now, it's probably best to ignore the ambient and concentrate on the light you can control most directly.