Dikdik Loc: Winnipeg, Canada

"As I have said the camera is set at f-5.6 and 1/60 second. All settings are manual."

A typical electronic strobe flash duration is 1/5,000 of a second or a lot faster. For this reason, your camera shutter speed has little effect on the exposure. If your shutter speed is 1/100 seconds, and if the flash duration is 1/10,000 seconds, as long as the flash occurs during the 1/100 sec the shutter is opened, the photograph has been taken.

Cameras are designed to have an optimal exposure speed for using a strobe. Your 1/60 of a second seems slow; the shutter is usually sync'd for 1/125 or one setting faster. Early cameras that used flashbulbs were sometimes sync'd for 1/60, but, not common.

If your flash is not metering (programmed to give an amount of light and measuring it) then you have to get the guide number for the flash you are using. With a little trial and error, you can calculate an approximate one by taking numerous flash exposures using different aperture openings. You have to do this at several different distances. By picking the best exposed picture and noting the aperture, multiply the distance and the aperture opening and this will be a good guess at the guide number for the flash. You can check this for the different distances and you should end up with a similar guide number. This assumes that your flash is not already automatic and is adjusting the amount of light it flashes. Once a guide number is established it is a matter of dividing the guide number by the distance to get an aperture opening.

This is a bit dependent on the ISO setting, but, inclusion of this gets really complicated. Your ISO should arbitrarily be about 500-1000. Others may have a better value.

The f 5.6 will allow a certain amount of light in. The amount of light is what is reflected off the object by your strobe. The brighter the strobe, the more light that is reflected, and the smaller the aperture that is required. Similarly the closer the object, the more light that is reflected, and the smaller the aperture that is required.

You've had a couple of 'crusty' replies... don't give up, there are lots of people that can help. You should also do a little research on flash photography... it's all part of the learning curve. Have fun.

Dik

Weddingguy Loc: British Columbia - Canada

A few of the following statements are not only incorrect but could be confusing to a novice . . .

A typical electronic strobe flash duration is 1/5,000 1/3,000th of a second or a lot faster. For this reason, your camera shutter speed has little NO effect on the exposure until the shutter speed reaches the flash duration . If your shutter speed is 1/100 seconds, and if the flash duration is 1/10,000 seconds, as long as the flash occurs during the 1/100 sec the shutter is opened, the photograph has been taken and all of the light from the flash has been recorded .

Cameras are designed to have an optimal maximum exposure speed for using a strobe. Your 1/60 of a second seems slow but will not change the exposure from the flash . . right? the shutter is usually sync'd for 1/125 or one setting faster The shutter is sync'd with all shutter speeds up to the maximum sync'd speed of usually 1/180th to 1/250th second . Early cameras that used flashbulbs were sometimes sync'd for 1/60 were sync'd at ALL shutter speeds because the flash fired before the shutter opened and lasted until after the shutter closed except for very short shutter speeds , but, not common always . Another difference between flash bulbs and electronic flash is: Because the flash duration of the flash bulb was so long, shutter speeds faster than 1/60th second closed the shutter before all of the light from the bulb was recorded . . . so faster shutter speeds DID affect exposure because not all of the light from the bulb was used.

If your flash is not metering MANUAL FLASH (programmed to give an amount of light and measuring it) then you have to get the guide number for the flash you are using. With a little trial and error, you can calculate an approximate one by taking numerous flash exposures using different aperture openings. You have to do this at several different distances. By picking the best exposed picture and noting the aperture, multiply the distance and the aperture opening and this will be a good guess at the guide number for the flash. You can check this for the different distances and you should end up with a similar guide number. This assumes that your flash is not already automatic and is adjusting the amount of light it flashes. Once a guide number is established it is a matter of dividing the guide number by the distance to get an aperture opening.

This is a bit dependent on the ISO setting, but, inclusion of this gets really complicated. Your ISO should arbitrarily be about 500-1000. Others may have a better value. The ISO being used does not matter as long as it is consistent. Changing the ISO will change the guide number.

The f 5.6 will allow a certain amount of light in. The amount of light is what is reflected off the object by your strobe. The brighter the strobe, the more light that is reflected, and the smaller the aperture that is required. Similarly the closer the object, the more light that is reflected, and the smaller the aperture that is required.

Dikdik Loc: Winnipeg, Canada

Thanks for the comments/corrections... Didn't know strobe speeds were as slow as 1/3000 sec. My Nikon F2 and Nikkormat (sp?) was sync'd at 1/125 sec. This could become part of a FAQ.

Corrected:

A typical electronic strobe flash duration is 1/3,000th of a second or a lot faster. For this reason, your camera shutter speed has no effect on the exposure until the shutter speed reaches the flash duration. If your shutter speed is 1/100 seconds, and if the flash duration is 1/10,000 seconds, as long as the flash occurs during the 1/100 sec the shutter is opened, the photograph has been taken and all of the light from the flash has been recorded.

Cameras are designed to have an optimal maximum exposure speed for using a strobe. Your 1/60 of a second seems slow but will not change the exposure from the flash. The shutter is usually sync'd for 1/125 or 1/250 sec. The shutter is sync'd with all shutter speeds up to the maximum sync'd speed.

Early cameras that used flashbulbs were sometimes sync'd at ALL shutter speeds because the flash fired before the shutter opened and lasted until after the shutter closed except for very short shutter speeds. Another difference between flash bulbs and electronic flash is: Because the flash duration of the flash bulb was so long, shutter speeds faster than 1/60th second closed the shutter before all of the light from the bulb was recorded. Faster shutter speeds affected exposure because not all of the light from the bulb was used.

If your flash is MANUAL FLASH (programmed to give an amount of light and measuring it) then you have to get the guide number for the flash you are using. With a little trial and error, you can calculate an approximate one by taking numerous flash exposures using different aperture openings. You have to do this at several different distances. By picking the best exposed picture and noting the aperture, multiply the distance and the aperture opening and this will be a good guess at the guide number for the flash. You can check this for the different distances and you should end up with a similar guide number. This assumes that your flash is not already automatic and is adjusting the amount of light it flashes. Once a guide number is established it is a matter of dividing the guide number by the distance to get an aperture opening.

This is a bit dependent on the ISO setting, but, inclusion of this gets really complicated. The ISO being used does not matter as long as it is consistent. Changing the ISO will change the guide number.

The f 5.6 will allow a certain amount of light in. The amount of light is what is reflected off the object by your strobe. The brighter the strobe, the more light that is reflected, and the smaller the aperture that is required. Similarly the closer the object, the more light that is reflected, and the smaller the aperture that is required.

Dik

GoofyNewfie Loc: Kansas City

The Nikon SB-800 has a flash duration of 1/1050 at full power.
Its not fast or slow, it's a duration. ie: brief or longer.
Here's an older list of a few speedlights and flash duration:
https://improvephotography.com/46974/flash-duration-speedlights-long-pop-flash/
And a chart showing flash duration of the Godox AD600 battery powered monolight shows as long as 1/220 sec at full power and a brief as 1/10000 at 1/256th power
http://www.thebroketographers.com/blog/2018/4/9/update-flash-duration-analysis-for-godoxflashpoint-ad600

amfoto1 Loc: San Jose, Calif. USA

This is a very complicated subject!

Guide Number (GN) is a measure of light power of portable flash units. With studio strobes, Watt Seconds (WS) are usually used instead.

GN is stated in distance... feet or meters... that the flash reaches and is SUPPOSED to be calculated using flash coverage for a normal lens (50mm on full frame, or other focal length on other formats), usually at 100 ISO. HOWEVER, many portable flash are fitted with Fresnel lens in front of the flash tube, which are adjusted to widen or narrow the coverage for different lens focal lengths, and this also changes the distance the flash can reach with its illumination... hence the GN changes. Many flash manufacturers have gotten in the habit of stating their GN with that Fresnel lens set to it's most telephoto... usually 105mm... which will give the greatest reach, but the narrowest illumination. Earlier flashes with one, you had to manually install or set that Fresnel to match the lens you're using. Many newer and current flashes "communicate" with the camera and lens, and automatically adjust the Fresnel unless you override it and set it yourself.

Manufacturers use the telephoto setting because it makes their flashes sound more powerful!

I use Canon gear and can tell you that they use 105mm lens setting on all their flashes that are variable. In fact, their flash designations are derived from the resulting guide number. For example, 580EX flashes I use have a 58 meter GN at the 105mm setting and 100 ISO. A smaller 420EX flash has 42 meter GN. A couple macro flashes I use are much less powerful (a big flash is too bright for close-ups).... GN 14 meters and 24 meters respectively. This is pretty consistent with all the "EX" series flashes Canon offers... the flash model number reflects the flash's GN at ISO 100 and, in cases where they use a Fresnel, the 105mm setting. (I'm not sure about some earlier series of Canon flashes. I'm pretty sure their A-series model number don't reflect the GN... But some other series might.)

Other manufacturers.... well it's anyone's guess. Check the user manual!

It's similar with studio strobes.... actual illumination varies depending upon what type of modifier is used on the strobe. However, WS are a more "pure" and invariable designation of the power of illumination. WS is actually a rating of the capacitor power of the strobe... not the amount of light it puts out. But even so the actual reach possible will vary a great deal depending upon whether you are using the strobe directly with a standard reflector installed, or using it with a "beauty dish" that causes a wider light spread, or have it inside a light box (which come in a wide variety of sizes), or are bounding it out of an umbrella. With umbrellas, it depends upon their reflectivity. Some are white and less reflective than others that are lined with a silvery fabric. There are also light modifiers that diffuse or otherwise change the nature of light, and it's strength. These are available for both studio strobes and portable flash. With flash, it also makes a big difference if it's being bounced.... including the reflectivity of the bounce surface and how far away that surface is from the flash, as well how far the subject is from the bounce surface. There are a TON of variables!

It's not really possible to convert WS to GN.... A strobe with a particular WS rating will have variable GN depending upon the above factors. But just to give you rough idea, I have a portable five-strobe setup where each light is rated for 320 WS.... that's roughly as powerful as a GN 80 portable flash. (But for my main light I usually gang up two of those monolights and bounce them out of single large umbrella.... who knows what the actual guide number ends up!)

With studio strobes and purely manual flash, the most accurate way to determine exposure is to walk over to where your subject will be located and test fire the lights while taking a measurement with a flash meter (I use Sekonic L358, no longer made but similar to L308. I've also used Minolta IIIF and IVF, decedents of which are now being made by Kenko). This is very with a single flash or strobe, but that's not often the way things are illuminated.... Multi-light setups are more common in studio settings with those you ultimately need an overall exposure measurement, but might first use the meter to set up each light individually... adjusting the output and/or moving each individual light source to achieve a particular "light ratio" between them. For example in a simple two light setup one might use a full power "main" light on falling onto side of the subject, and a second light at 1/4 power on the opposite as "fill"... a 4:1 ratio. This is done in order to render some shadow effects and give a sense of depth to an image. The meter is used to set up that light ratio, popping each strobe or flash off individually. But the overall illumination of all the multiple light sources firing together then needs to be measured to determine correct camera settings.

Older flash units provided a level of automation using a "thyristor" arrangement. This was basically a where you would "dial in an f/stop" on a little scale on the back of the flash, which shows you the range of distance closest to farthest, which the flash is able to illuminate. All you had to do was determine if the distance between the flash and the subject was somewhere within that range. This type of flash also has a sort of light meter built into it, which it uses to measure the illumination and make some simple adjustment to it's own output.

Newer flash units work in conjunction with the camera instead. In most cases, they first fire at greatly reduced power (approx. 1/64) to take a meter reading (using the meter built into the camera), and then adjust a "full power" pop timed to the shutter release to make the actual exposure. This happens so quickly that most people don't even realize the flash fired twice. And it makes for pretty accurate auto exposures with flash, which can still be adjusted using exposure compensation techniques (much the same as using exposure compensation with non-flash auto exposure modes).

As to camera settings....

First is ISO or sensitivity (as dictated by the film being used... or as set by the user with digital).

Second is shutter speed. Any camera using a focal plane shutter has a "flash sync speed". This is the fastest shutter speed that can be used with flash, and get a fully illuminated image. A longer shutter speed can be used, but generally won't matter as far as the flash is concerned. Instead, longer shutter speeds will increase the amount of ambient light that's captured. Many modern flash also have High Speed Sync, which allows shorter shutter speeds to be used, by shortening the duration of the flash and carefully timing it to coincide with the shutter. This significantly reduces the distance the flash can reach.

Flash sync speed with most APS-C DSLRs is 1/200 or 1/250. With full frame cameras it's usually a little slower.... 1/160 to 1/200 is common, depending upon model. Studio strobes also fire more slowly than portable flash, so slower shutter speeds are often needed (typically 1/200 max with APS-C and usually 1/125 or 1/160 with full frame).

The reason that shutter speed isn't very important with flash is because the very brief illumination sort of acts like a shutter itself. In fact, a typical portable flash will have duration equivalent to at least 1/720 second at full power. It may be even shorter duration, especially with reduced power settings. Flash can be helpful freezing rapid movement.

The third and final camera adjustment is f-stop and this setting is dictated by distance.... how far from the flash the subject will be when the photo is taken. When trying to set this manually and without a flash meter or reference chart, complex calculations using the Guide Number or Watt Seconds, selected ISO and measured distances are necessary to determine what f-stop to use. Even then, test shots should be taken and fine-tuning exposure adjustments may be needed.

The way we did it "back in the day" was to do a bunch of testing with our gear, then set up a little cheat sheet to reference. If we only used one film speed, always set the same shutter speed, with the same flash power setting (including the same modifier or the same Fresnel lens setting, if the flash had one)... all that remains is the distance variable and that dictates what f-stop we need to use for "correct" illumination. In other words, by keeping most settings consistent, all that was needed was a list of f-stop and distances (lenses that have a distance scale are helpful... when having trouble judging by eye, simply focus on the subject and read the scale on the lens). The older flashes themselves often provided this with a little dial on the rear. There also were simple flash calculators available. They were round plastic "dials" where you'd set that same info and then read out the correct f-stop to use. I don't know if those are still available... but if you have a smart phone, I bet there's an app for that!

Modern flashes do a lot of the above automatically... but mine still display a distance range on their LCD panels, just as a way of confirming if subjects are too near or too far for the flash to illuminate properly.

So, really, there's no way to answer your question, based upon what you've told us. We can't tell you what to use without more info about the power of your flash, whether it's being used with any sort of modifier like a Fresnel lens or bounce or diffuser, what ISO you're using, and the distance to your subject. Less important, but still a possible factor is the shutter speed being used. You've only given us a couple factors: f/5.6 is the aperture you've set and 1/60 the shutter speed you've chosen. We don't know how you arrived at those and without the rest of the info involved, we simply have no way of saying if that's a correct aperture or not.

Some years ago I picked up a book about portable flash by Susan McCartney. I don't know if that's still available, but it was very helpful!

But even easier is modern highly automated, dedicated and TTL metered flash. It works great, IMO!

Dikdik Loc: Winnipeg, Canada

Thanks for the detailed info.

Dik

jeep_daddy Loc: Prescott AZ

Sorry I misinterpreted flash meter. I assumed he meant the actual readout on the back of the flash that gives a person the distance in feet (usually). I wasn't thinking of a Light Meter or Incident Meter

BebuLamar

I really don't know what the OP wanted.

lorvey Loc: Lincoln, Nebraska

Wow! Seems to me everyone is making this way too complicated. Set your camera to shutter priority. Set your shutter speed and the camera will set your f-stop automatically. If you want a little more depth of field, decrease your shutter speed. If you want less depth of field, increase your shutter speed. But in most cases, your flash will determine your depth of field. The nice thing about digital cameras is that you can try different settings, look at the results, and then make your own decisions about settings you prefer.

GoofyNewfie Loc: Kansas City

The flash does not determine depth of field- aperture does.
The aperture setting also affects how much power is needed from the flash for a correct exposure.
My personal preference, if I'm shooting in an auto mode, is aperture preferred-I want to control the depth of field directly.

Architect1776 Loc: In my mind

If you are in all manual you need to know the guide number and distance. As distance changes so does the aperture. F5.6 is for one distance depending on the guide number. Or if the flash has power settings then those can be changed as aperture and or distance is changed.
I suggest you get a book or study flash on the internet. Just asking what aperture doesn't give any information that is useful.

Bipod

WARNING: SOME OLDER FLASH UNIT MAY DAMAGE SOME ELECTRONIC CAMERAS
You need to make sure the trigger voltage does not exceed the camers's specs.
Fortunately, this is pretty easy.

The minimum interface between any flash and camera is the trigger switch.
This is the center button on an ISO hotshoe (and most proprietary hot shoes).
On even older cameras with coldshoes, it is provided by the X jack and a cable.

Many old flash units used high volrage -- sometimes as high as 400 Volts --
to sense this switch. That worked fine on mechanical cameras with a mechanical
swtich, but it will fry an electronic film camera or digital camera that
doesn't have special protection built into it.

Your camera's manual should tell you the maximum flash trigger voltage
it can tolerate. Your flash unit's manual should tell you the voltage.
If you don't have the flash manual, here's list:
http://www.botzilla.com/photo/strobeVolts.html

Since there are many makes and models of flash units, it's not a bad idea
to measure the flash trigger voltage with a digital volt meter. Be careful
not to electrocute yourself. 400 VDC will kill you dead.

If your flash voltage is too high for the camera, you will need a voltage
adapter to use it. I use a Wein Safe-Sync.

tallshooter

I believe OP got what he wanted and he is gone.

BebuLamar

I wouldn't worry about that!

Bipod

This post mostly repeats what others have said, but is more systematic and detailed.

The OP asked about aperture for the flash which sounds like an Automatic universal flash
of some sort, but I can't really be sure since he wasn't specific. So I'll just cover all the bases.

There are several kinds of on-camera flash units:

I. Universal --works with any camera (subject to voltage limitaitons!)
Only 1 connector in hot shoe: the trigger.
Dumb: -- no controls
Variable: -- allows you to vary the power
Smart -- contains a photocell, quenches flash after a predetermined amount of light
has been reflected from the subject. These unis sometimes are marked "Thyristor Controlled".

II. Dedicated: first only selected make/models, multiple conductors in hot shoe
Dumb -- like the above, but supports camera feature(s) (e.g., READY light in viewfinder)
Variable -- ditto
Smart -- ditto
TTL -- uses your camera's light meter. Camera controls the flash.

How you use the flash depends on what kind it is:

Dumb -- You need to know the flash units Guide Number. Guide numbers have
a unit: either feet or metes (usually both Guide Numbers are given).
1. Look up the flash's guide number in your favorite unit of measure (feet or meters).
E,g, 80 FT
2. Measure or estimate the distance to your subject in this unit. E.g 10 ft
3. Divide the guidenumber by the distancce: e.g., 80 ft / 10 ft = 8
4. Set this aperature on your camera. E.g., f/8
5. Set your camera's shutter speed to its maximum synch speed. E.g. 60
(Or slower, if you want more ambient light and slight overexposure).
6. Take the shot.

Variable -- Has a maximum power Guide Number. Compute as above. If you don't
like the aperture, you can reduce the power (and the Guide Number) and uses a
larger aperature.

Automatic -- These usually support Manual mode (proceed as with Dumb, above)
and at least one Automatic mode. Usually there are different automatic modes
for diffrent distance ranges: A1, A2, etc.

1. Measure or estimate the distance from flash to subject subject in your favorite
unit (feet or meters). E.g. 10 ft.
2. Enter your ISO film speed or digital ISO speed setting into the flash unit.
E.g., ISO 100.
3. Select the the Automatic mode that includes this distances. Eg. A2: 3-15 ft.
4. It will display an f-number. E.g., f/4.
5. Correct this number by total filter factor of any filters that are screwed to the lens.
6. Set this f/stop on your lens aperture ring (or however your cameras does it).
7. Take the shot.

The Automatic flash will measure the total amount of light that has been reflected
from the subject (and room) back at the flash. When this matches the predtermined
threshold, it will quench the Xenon tube, shutting off the light. If the subject and
reoom are "average" reflectance (tones), this will be a "normal" exposure.

Some Automatic flashes have a button that allows you to take a test flash, and an
indicator that lights up if the scene received enough exposure. If it didn't you
will need to move closer to your subject. This is very handy when shooting film.

The Vivitar 385 automatic flash supported an accessory cable taht allowed the
light sensor to remain on the camer while the flash was moved to a handle or
light stand. This was extremely useful.

Finally, if you have a flash meter, then it can be great assistnace when using any
Dumb, Variable or AUtomatic flash.

Dedicated Flash -- same as Automatic flash, with additional features.

TTL Dedicated Flash -- follow flash manufactuer's instructions. The camera
knows the ISO speed, so you don't have to enter it. Since the metering is TTL,
filters will automatically be accounted for. There are two DIFFERENT methods
of operation (sometimes you have a choice):
Method one: test flash of known brightness used to measure scene reflectivity
Method two: measure as you go (like an Automatic flash, but using the camera's meter)

Some cameras using method one flash up to three times to take one exposure:
1. Pre-flash (to set exposure and white balance)
2. Red-eye reduction flash
3. Exposure flash
This happens so quickly that it looks like one flash to the naked eye.

These flashes have far less power than they would if they only made one burst.
Also, opitcal triggers (to control slave flashes) cannot be used with flash systems
that flash more than one time per exposure.

TTL dedicated flashes are characterized by their high cost and complexity, but
are convenient to use and eliminate some (not all) of the guesswork.

It's not a bad idea to label flash units (of all kinds) with their trigger voltage and
full-power guide number: e.g., 150 VDC 120 FT.