New to using flash

Greetings,

 

I am completely new to using a manual flash but have ordered an Altura Photo AP-UNV1 universal flash. On the back of the flash is the power selector which goes from 1/128 to 1 to 1. Is each one of those power outputs the shutter speed that i have to select in order to get a proper exposure? For example, when i select the weakest output which is 1/128 does that mean my shutter speed should be 1/128th of a second and when i go one step up in intensity to 1/64 does that mean my shutter speed should be 1/64th of a second? I am completely new to using a flash other than the pop one on my canon t3i/600D and any help would be greatly appreciated.

The power settings on the back of the flash have nothing to do with the shutter speed that you set on the camera. Set your camera to the X sync speed (Probably 1/180 on your Canon). Since the meter in the camera won't measure a manual flash, you will have to set exposure either by using the calculator on the flash or by experimenting and chimping. Good luck!

Greetings,

 

I am completely new to using a manual flash but have ordered an Altura Photo AP-UNV1 universal flash. On the back of the flash is the power selector which goes from 1/128 to 1 to 1. Is each one of those power outputs the shutter speed that i have to select in order to get a proper exposure? For example, when i select the weakest output which is 1/128 does that mean my shutter speed should be 1/128th of a second and when i go one step up in intensity to 1/64 does that mean my shutter speed should be 1/64th of a second? I am completely new to using a flash other than the pop one on my canon t3i/600D and any help would be greatly appreciated.

 

Certainly you have got the directions wrong and need to watch the You Tube video as I just did. A purely manual flash without any metering in the flash or connectivity with the camera throws you back to using a chart based on the flash intensity and computing distances and therefore your f stop. Shutter is not the significant factor as you will find out when you do more reading on flash. I would add that the flash you bought is a primitive device that I would never recommend except for its slave use. Get one with at least an auto mode and a little receptor to measure the flash according to f settings. Beyond that, it would take a lot more to answer your questions without a complete tutorial. Guess you have to do some more homework. Sorry. But there are many affordable flashes that make life easier. Yours alas is not so great for the easy part...why waste time is my advice. Go for something a little cooler, friend. I wish you well.

READ the manual for the flash.

Then start shooting with it. The more you shoot and try, the more you learn.

 

I would also get a 'camera flip' flash bracket to use with the flash. This keeps the flash above your camera when you flip from H to V orientation.

Stroboframe Quick Flip 350 Bracket 310-635 B&H Photo Video

You will also need a sync adapter/cable to go from the hot shoe of your camera to the flash bracket.

I agree with Gerry

I would get at least an auto flash, even better an iTTL flash.

• Auto while not as good as iTTL works quite well. Just chimp the shot and adjust the aperture or Exposure Compensation to get the image darker or brighter. And shoot the adjusted shot. I used an auto flash for YEARS before getting an iTTL flash.
   
  
• The iTTL flash will take the pre-flash reading through the lens, so compensates for a longer lens where an auto flash cannot.
  

But if you are going to do multi-flash work, then you want full manual, to control each flash separately. Most auto and iTTL flashes can be set for manual.

 

I grew up on manual cameras, flashes, and film, and became quite good at it. You guess the range/distance to the subject lookup the distance on the dial/calculator and read off the aperture, then set the aperture. In practice you can get quite fast at it. But it will never be as fast as auto.

But if you have odd lighting conditions, the first shot with a manual flash can be better than the first shot with an auto flash.

Thank you all for the replies! thank you Gerry for the well wishes!

 

I guess I had it all wrong then. I was trying out the flash after watching the video about it online, and tried out a few different settings and got some very usable shots. I haven't shot in all manual since my high school photography class ages ago.

 

I like the manual flash after testing it out a bunch, but i would like an iTTL flash some day. What are some good iTTL flashes that I could use on my Canon? I do not know which brands are good and which to avoid.

I am not a big user of flash, although long ago I did do the totally manual (distance, etc) routine, because there wasn't any alternative.

Then the camera makers started offering "automatic" flash, making life a living hell for third-party flash makers.

 

Not the least of the reason for this change was to get you to buy the OEM flash, instead of something else (cheaper).

 

Proper flash lighting is a complicated business and I'd look on line for some of the many tutorials on the web and YouTube.

 

But the simple answer is that in many ways the OEMs succeeded. If you want to use ALL of the capabilities of most new cameras, the safest course is to buy the flash made for your camera. Sorry :(

 

That's what I did, but I still ended up sending my unit to my daughter who shoots the same brand. I just didn't use it enough to bother.

Let me try to help you out a bit, being from the "Dinosaurs roaming the earth" stage of photography with "exploding flashbulbs"!

:cool:

You need to make a "whiz wheel" or chart, which is really easy to do.

You start with a "Guide Number" all this is relates to the film speed (ISO) F-stop (aperture) & distance to subject.

All a "Guide Number" is is the Correct f-Stop for correct exposure at lets say 10 feet (in a normal sized room). Example: Correct exposure for 100 speed film is f 5.6 @ 10 feet. OK your guide number is 56 for 100 speed film. (aperture X distance.)

Now its divide & multiply time.

For 50 ISO film your guide number is reduced to 40 because the correct exposure would be at f4.0, for 200 speed it would be 80 because you'd use f8.0.

Now all you do is focus, apply the guide number & set that power on the flash. AS you halve each step of the variable manual power you open 1 stop. so if you use the numbers above you'd get:

FULL-56

1/2 = 40

1/4 = 20

1/8 = 10

& so on.

I actually have several flashes with the same feature so I have them as pages in an Excel spreadsheet.

:oops:

"i-TTL" won't do you any good. That's Nikon's system! For a modern Canon camera you need an E-TTL ii compatible speedlite.

 

The advantages are that the camera+flash take care of the exposure entirely automatically.

 

However, Guide Numbers work OK, and IMO you don't need a calculator, just some mental arithmetic skills. The GN is the aperture multiplied by the distance from the flash. Given the guide number, you just divide it by the subject distance to get a suitable aperture. But be aware that flash manufacturers blatantly lie about the GN of any flash. A flash advertising a GN of 36 or above (in metres @ 100 ISO) will in reality have a GN not exceeding 28. Forget the "zoom" head setting; it makes almost no difference to the exposure.

 

In fact if you assume a GN of 28 (metres) or 90 (feet) @ 100 ISO, you won't go far wrong.

 

So for example at 10 metres subject distance an aperture of f/2.8 will be about right. At 4 metres you need to set f/7 (f/8 is close enough) and at 2 metres f/16 will be good. Not rocket science needing a calculator, and an approximation is all you need.

Edited May 11, 2017 by rodeo_joe|1

Agreed on the auto & TTL, but I think his original question related to using the flash manually where the TTL wouldn't be workable. As for fudged Guide numbers thats easily solved by my method of actually making a few test exposures to establish a "real world" guide number which would be good.

The suggestion of a chart or whiz wheel was more to give him a visual learning tool than any actual exposure calculations, although it would do that as well.

I have older units & they actually all have exposure calculation scales on the unit. Something then flash he's looking at seem to not have!

The best way to use such a flash is to guess,shoot, check, readjust, shoot, check etc... Soon your first guess would be very close. Using guide number has a lot of problems. You can't use it for bounce or using any light modifier like soft box or umbrella. The rated guide number is often inflated. The power settings not really very accurate i.e 1/2 isn't exactly 1/2 full power. Edited May 12, 2017 by bebu_lamar

Let me try to help you out a bit, being from the "Dinosaurs roaming the earth" stage of photography with "exploding flashbulbs"!

:cool:

You need to make a "whiz wheel" or chart, which is really easy to do.

You start with a "Guide Number" all this is relates to the film speed (ISO) F-stop (aperture) & distance to subject.

All a "Guide Number" is is the Correct f-Stop for correct exposure at lets say 10 feet (in a normal sized room). Example: Correct exposure for 100 speed film is f 5.6 @ 10 feet. OK your guide number is 56 for 100 speed film. (aperture X distance.)

Now its divide & multiply time.

For 50 ISO film your guide number is reduced to 40 because the correct exposure would be at f4.0, for 200 speed it would be 80 because you'd use f8.0.

Now all you do is focus, apply the guide number & set that power on the flash. AS you halve each step of the variable manual power you open 1 stop. so if you use the numbers above you'd get:

FULL-56

1/2 = 40

1/4 = 20

1/8 = 10

& so on.

I actually have several flashes with the same feature so I have them as pages in an Excel spreadsheet.

:oops:

 

Your guide number is not correct.

If full power the guide number is 56 then

1/2=40

1/4=28

1/8=20

1/16=14

Corrected, thanks.

The one thing that is a pain with a manual flash, that is much easier with an auto flash is bounce flash.

I can just point the sensor at the subject, point the flash at the ceiling or wall, then let the flash figure out how much light to put out.

But with a digital camera, doing it manually isn't the difficulty that it was in the film days. You shoot, chimp then adjust, and repeat till you get the exposure right.

 

bebu,

If you are shooting direct (not bouncing) then the GN or calculator wheel is very valid.

You still have to do a test to determine what YOUR GN is. But once done, the calc wheel works just fine.

Depending on where and what you are shooting, you may be shooting direct flash rather than bounce, so don't write off the GN/calc wheel.

When I shot graduations and events, it was impossible to bounce (outside or ceiling 25+ feet up), so it was all direct flash. And with things moving, I did not fuss with power settings, just one setting and go with it. And I did NOT have the time to experiment to determine exposure for various shots, things are moving. The calc dial worked very well in those conditions. Just estimate the distance, look up the distance on the wheel and the matching aperture, set the aperture on the lens and shoot.

I found that simply adding the "legs" of a bounce shot & then calculating for the total distance worked for me with manual bounce.

Flash to wall 8', wall to subject 10' subject to camera 7' calculate for 25' (8+10+7).

Where i frequently use more than one flash the bigger problem for me is getting the 3 to respond as individuals, rather than reading each others output & mis-reading the total.

I guess its what you're used to but I just automatically go to manual & power ratio when I'm in that situation because I'm so practiced with it.

No need to start with a guess. I've measured the real guide number of numerous different makes and models of flash using a flashmeter, and double checked using other flashmeters. Then triple checked with camera exposures.

 

My findings are that hotshoe flashes fall into 3 categories, which I'd rate as topline, second rank and also-rans.

 

Topline speedlights (or speedlites) from the likes of Nikon, Canon, Metz, Nissin, Godox and Yong Nuo all measure as having a GN of between 28 and 32 - metres @ 100 ISO. That's within 1/3rd of a stop of each other and an almost insignificant difference. None of them came close to their claimed GN.

 

Second rank flashes are those from good makers, but just with a lower power rating than the "flagship" models. These all measure as having between 20 and 22 GN.

 

The also rans are from obscure makes, or obviously tiny little flashes. Not worth a second look IMO. Their guide numbers vary a lot, but barely crawl into double figures.

 

So as a starting point a GN of 28 is better than a guess for any decently powerful flash. Or 22 if it's not one of the top makers top models.

 

Even bounced flash is fairly easy to get a starting point with. Use the GN with the total distance from flash to subject via the bounce surface, then open up another stop for a white-painted surface.

 

Chimping the exposure from a close estimate is much better than starting with a wild guess - or with the maker's stupidly inflated GN.

Since the OP is a new comer I say guess, chimp, adjust cycle. For me as I have done it so many times my first guess is quite close and often usable if I don't have a chance for another shot.

How difficult is it to divide 28 or 90 by the subject distance in metres or feet? Then find the nearest aperture number that comes close.

 

Guessing and chimping without knowing anything of what's changing and why is no way to learn!

Thanks for the help everybody! I found a shutter speed and aperture to start off with, but i also downloaded some flash apps onto my phone. Slowly but surely I am beginning to learn.

A dial wheel (or sliding) exposure calculator is easier to use than your phone.

Using a flash is a place where KISS works well.

Your flash "should" have one on the back.

Leave the shutter speed on 1/125th of a second. If flash is the main source of light, then the shutter speed plays no part in getting a correct exposure. The reason for this is that the duration of the flash is so short that it alone controls the exposure time.

 

This means that the only controls you have over flash exposure are the lens aperture and camera ISO setting. Leaving aside varying the flash output itself.

 

As already explained, for a given ISO setting there are set combinations of aperture and flash-to-subject distance that work, and these give the Guide Number.

 

Mathematical explanation: Light from a small source like a flash, loses power as the distance from the source increases. This is called "falloff" and the falloff follows a law that says the light intensity varies as the inverse square of the distance. Meaning that if the distance doubles, the light intensity reduces to one quarter. 3 times the distance = 1/9th intensity. 4 times the distance = 1/16th.... etc.

 

Now aperture numbers also vary exposure as the square of their number, with the result that multiplying the aperture number by the flash distance results in a constant number; the Guide Number. Conversely, dividing that GN by the distance gives you the aperture for a correct exposure.

 

Things get a bit more complicated when it comes to varying the ISO, but to cut it short: Doubling the ISO multiplies the GN by 1.4 (the square root of 2) and raising the ISO by a factor of 4 doubles the GN.

 

None of this needs to worry you if you have a phobia of maths, but if you're not numerically challenged it explains almost everything you need to know about flash exposure.

Edited May 14, 2017 by rodeo_joe|1

Yes but the flash he is buying seems to not have one!

Either that or it's a layout I can't recognize?

I think each vertical bar is supposed to indicate a "power" level. Varying the flash intensity by one stop(?) each from full down to 1/128th.

 

If we give it the benefit of the doubt and say it has a GN of 28 (metres @ 100 ISO) at full power then the GNs for the rest of the power levels will be:

1/2 = GN 20 m / 64 ft

1/4 = GN 14 / 45 ft

1/8 = GN 10 / 32 ft

1/16 = GN 7 / 23 ft

1/32 = GN 5 / 16 ft

1/64 = GN 3.5 / 12 ft

1/128 = GN 2.5 / 8 ft

 

The lower power levels won't be of much practical use except as a "fill" light, but the explanation of that is possibly best left for another thread.

That's actually my favorite use for the built in popup flash in the camera. I just set it to be a full stop under as a flash exposure compensation.