tests done for max flash power -SB900 SB700 yongnuo 560III

rocketman122

Senior Member
Ok had this mood to test my flashes. so far did just 3 SB900 SB700 yn560III-will do the others as well.

I put the flash on a yn622n transceiver. put my sekonic l-718 flash meter on a light stand using a manfrotto clamp with stud. I measured 1m and placed the flash head exactly 1m from the light meters dome head.

SB900/ used it at the 35mm zoom head setting. manual power mode. aperture was the highest it could go which was f/64
Sb700 doesnt have the aperture setting selector. just power amount and zoom
560III is the same as SB700.
I used a 622n transceiver to fire the flash. waited 30 seconds in between each pop. energizer 2300mah NIMH batts were used. quite new. opened 3 new packs of them and they were recharged overnight. each flash got a new set. and were tested from the first pop. meaning, I didnt put the new batts in and fired off a shot. I put them in, made sure the channel on transceivers was good, set it up and shot as to give the batts as much power as possible.
light meter is a sekonic l-178 and was set at iso 100 1/125 shutter and only measured for flash and not flash and ambient mixed.


results. this test was just for pure max power at 1m at 35mm zoomed head

SB900
-1st pop--- f/16 + 7/10 stop (maybe I was off on distance and remeasured)
-2nd pop--- f/16 + 9/10 stop
-3rd pop--- f/16 + 9/10 stop

Sb700 and this kinda surprised me
-1st pop--- f/16 + 9/10 stop
-2nd pop--- f/16 + 9/10 stop
-3rd pop--- f/22

yongnuo 560III
-1st pop--- f/22 + 2/10 stop
-2nd pop--- f/22 + 3/10 stop
-3rd pop--- f/22 + 3/10 stop


I was surprised by the SB700 matching the SB900 and I want to recheck this. could it be because the SB900 is an old model. in terms of age and use compared to my more newer and less abused SB700?

the 560III also surprised me because although specs say its as strong as the SB900/910, I thought it was more hype than truth. but here it shines. its very strong and also VERY fast to recycle. the SB700 is 2 years old, the SB900 is 3 years old and the 560III is less than a year old.

any questions, feel free to ask. maybe im missing something

I will test the metz 58 AF2 the SB28 I have, the yongnuo 568 flagship when it comes back and the SB800 (two I have). I will also ask my best bud nicely to let me test his new SB910 and see how that is as well.

cheers guys

IMG_4740 copy.jpg
 
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FastGlass

Senior Member
The first thing that comes to mind is how do you know the zoom head configuration between the three is the same? If I had three SB-900 and measured, than I would expect the same results. But having three diff units set at the same zoom doesn't necessarily mean the heads are the same even though the zoom setting is reading the same. Almost like having three strobes each having their own built in reflector and measuring them.
 

rocketman122

Senior Member
I dont know. but in tests for power, the zoom head is tested at 35mm. to me 35mm means 35mm like a 35mm lens, no matter who makes it. its supposed to cover a 35mm angle. these are things I cant test. so take it with a grain of salt. if you want me to test something just let me know. Im simply trying to see what theyre power is at a angle all 3 have. the 560III goes to 105 I think, the SB700 to 120mm and the SB900 to 200, if im not mistaken
 

WayneF

Senior Member
SB900/ used it at the 35mm zoom head setting. manual power mode. aperture was the highest it could go which was f/64
Sb700 doesnt have the aperture setting selector. just power amount and zoom
560III is the same as SB700.

Aperture in the flash menu settings are only a factor for the flash A or AA mode, which the SB-700 does not have.
That menu has no meaning or significance in flash M or TTL modes, where the power is as programmed.

Sb700 and this kinda surprised me


Surprised me too. You said 35mm zoom. Were all three also in the same DX/FX zoom mode too? They would be more equal if SB-900 was FX mode and SB-700 was DX mode, but which would not be a valid comparison of course.

You did not say what the precise measured distance was, or then we could have computed guide numbers, to judge if reasonable. :) The SB-900 numbers suggest distance was abut 6.6 feet, but this is a key fact to reveal.

The Nikon specs say SB-900 GN is 111.9 (35mm FX) and SB-700 GN is 91.9 (35mm FX). Which says SB-900 should be 1/2 stop stronger (at 35mm FX zoom).
 

aroy

Senior Member
Very interesting test.

What interest me is what is the full power output at working distance and the computed guide number. So I would set the meter at a suitable distance 5-10 meters depending on space, set the zoom at 35mm and then fire it at full power. To be doubly sure, I would try at various distances - 1, 2, 4, 8, 10 meters. After that I would use the program mode to see how well it works.

Another method if you have no meter is to use the DSLR. Set a target at 5 to 10 meters, and vary the aperture to get varying power in TTL mode. Then compare the histograms.

Once I get the measured guide number, I would then test for
a) Recycle time over the life of the battery
b) Battery life
 

co2jae

Senior Member
First of all, thanks for taking the time to share your test results with us. Second, as an uniformed extremely casual D7000 owner who does not even have a flash yet, could you just give me your opinion of which flash is the best bang for the "economical and on a budget" buck?
 

rocketman122

Senior Member
Aperture in the flash menu settings are only a factor for the flash A or AA mode, which the SB-700 does not have.
That menu has no meaning or significance in flash M or TTL modes, where the power is as programmed.


Surprised me too. You said 35mm zoom. Were all three also in the same DX/FX zoom mode too? They would be more equal if SB-900 was FX mode and SB-700 was DX mode, but which would not be a valid comparison of course.

You did not say what the precise measured distance was, or then we could have computed guide numbers, to judge if reasonable. :) The SB-900 numbers suggest distance was abut 6.6 feet, but this is a key fact to reveal.

The Nikon specs say SB-900 GN is 111.9 (35mm FX) and SB-700 GN is 91.9 (35mm FX). Which says SB-900 should be 1/2 stop stronger (at 35mm FX zoom).

Weird why the option to change aperture in manual mode isnt there. I never used the SB900 for manual only flash.

yes, 35mm zoom angle. the 560III doesnt have a DX/FX mode. I know the SB700 is in FX mode because when I bought it, I looked through the settings menu and the Sb900 is in FX to DX auto recognize mode.

we all know you are the flash tech guru here with tons of expertise. could it be the capacitors are just worn? cant understand how this is possible. when I was firing them I had to turn and closed my eye and still I could sense the flash quite hard. but with the SB700 it wasnt as but yet the numbers showed what I wrote. will do a short video as well showing how it was done.
I will do the SB700 and SB900 again soon in the evening to make sure what happened was accurate. im pretty confident in the 5600III specs. yongnuo noted the GN for this and said it was in line with the nikon flagship. really, a best bang for buck manual flash you could ever want to buy. build is fantastic, very fast to recycle very strong. win win.


Very interesting test.

What interest me is what is the full power output at working distance and the computed guide number. So I would set the meter at a suitable distance 5-10 meters depending on space, set the zoom at 35mm and then fire it at full power. To be doubly sure, I would try at various distances - 1, 2, 4, 8, 10 meters. After that I would use the program mode to see how well it works.

Another method if you have no meter is to use the DSLR. Set a target at 5 to 10 meters, and vary the aperture to get varying power in TTL mode. Then compare the histograms.

Once I get the measured guide number, I would then test for
a) Recycle time over the life of the battery
b) Battery life

I dont have more than 2 meters in a striaght line. dont want to go outside with this though. my house is tiny really and I did the test at 1m at 35mm angle at iso 100 because thats how almost most specs show them. I did this just for myself basically because having the 900 and 700, I opt to take the 900 thinking its much more powerful and im very confused with these tests myself. because when im shooting, I noticed the 700 isnt as strong at times. but like I said above I will do the test again just to confirm.

and for A and B on your to test items. thats a lot of flashes and I dont want to put more wear on my gear, because I beat on them hard in weddings. so I hope you understand. if I dont need to, id rather not. and B isnt really relevant to me since I always replace batteries in specific parts of the wedding. 3 times actually. after the ceremony, and twice during the dancing time. and in between first course and main course, the BG usually want pictures at the table with their guests. so three times is the amount I change and its always fine.

I wanted just to do a simply "flex what you got" test and see how their power is. the SB700 shocks me though. its not my final decision, but that SB700 is a powerhouse in such a small package. OH AND BTW GUYS. the SB700 and SB800 are the same sizes exactly. the SB700 has a shorter bottom half and longer upper half and the opposite is with the SB800 and since the SB800 is a powerhouse of a flash as it is, its very possible the SB700 is quite a strong contender (not as strong though) to the SB900. need to retest to make sure.

First of all, thanks for taking the time to share your test results with us. Second, as an uniformed extremely casual D7000 owner who does not even have a flash yet, could you just give me your opinion of which flash is the best bang for the "economical and on a budget" buck?

yes of course. for me as a pro as much as im a big "pro 3rd party" believer, I will have a nikon as my on camera flash at weddings. although I think their foot locking mechanism is crap at best. will wear out over time and start rocking and feel like its gonna come off. for those semi or prosumer guys, the yongnuo 565 or 568 are excellent. the 565 can be had for about $100 new shipped and is as strong as the SB900/910 and fast to recycle. be aware it cannot do HSS if you need it. the 568 does but it lacks the battery port should you ever need the option to use a battery port (to keep recycle times down to a minimum-eg shooting sports in CH mode) you can use the 565 or 568 as slaves and use your D7000 flash as a commander to fire any of these two models for more lighting possibilities.

co2jae, I contacted yongnuo 3 months ago regarding a 568 mark II (there is only a canon mark II) and having it as a MASTER and slave possible. because for on camera TTL, it cannot control other off camera TTL flashes and I have a hunch they will release this quite soon. probably during the summer. but for me, and after having the 568, and using it as an on camera main flash, its not the same.

what I LOVE about the yongnuo flashes that I think nikon lacks, is 2 simple things that make my life so easy. I dont need to press an unlock button to move the head left or right to to lift it up to bounce. and in weddings, split seconds matter. the other thing is when you open the battery door, it has a spring that lifts it open and holds it. the diagram for it is very helpful vs the nikons. its just horrible and on the dance floor in the dark is a real PITA to use. and one more thing, yea, I said 2, so shoot me. the foot locking lever on the nikon is fast and easy to use but after using so much, there is play in it. very noticeable play that makes you really feel the flash will fall off. with the YN flash, you have an old school turn to lock wheel that you can always tighten just a bit if you need to that gives you confidence the flash isnt going anywhere.

I also will do a test between 3 17-35 lenses soon. nikon 17-35 2.8 AFS tamron 17-35 2.8-4 and sigma 17-35 HSM 2.8-4
 
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WayneF

Senior Member
Weird why the option to change aperture in manual mode isnt there. I never used the SB900 for manual only flash.

No, not weird, or rather, very specialized purpose.

In manual flash mode, you simply set full power or 1/4 power, and that is what the flash does, period. It is up to the camera to set ISO and aperture to appropriate usable values. The flash could not care less, it just flashes at the specified power level.

But some flashes (SB-900, SB-800) have the automatic A mode (Auto mode, non-TTL auto). In this mode, the flash is self-metered, and has a front sensor that reads back its own flash, and it terminates the flash power level to be appropriate to the light result it sees. Works rather well, but the sensor is not through the lens, it sees and meters a different area than the lens or camera sees. But to know what the appropriate target exposure goal is, it has to know which fstop and ISO the camera is using, so it can compute the same exposure. CLS flashes obtain these numbers automatically from the hot shoe, but if the flash is off camera (no hot shoe), this A mode has to have a menu to set the ISO and fstop, so it can compute exposure. Just for this A mode (non-TTL auto). And for any GN mode, or manual mode distance scale too, but those don't work if not on the hot shoe.

But Manual or TTL flash has no use for it, does not need to know fstop or ISO.. All they have to do is flash at the power level setting specified for them to use.

yes, 35mm zoom angle. the 560III doesnt have a DX/FX mode. I know the SB700 is in FX mode because when I bought it, I looked through the settings menu and the Sb900 is in FX to DX auto recognize mode.

But what mode did they recognize off camera? Did you verify it? Such tests need to carefully control all variables. I don't exactly suspect this, but something was strange, unreasonable results for SB-700, and other than procedure, this is all I can think of. To be certain, I would set their menus directly to FX mode.
If the SB-700 was doing DX zoom, it would almost fully explain it.

we all know you are the flash tech guru here with tons of expertise. could it be the capacitors are just worn? cant understand how this is possible. when I was firing them I had to turn and closed my eye and still I could sense the flash quite hard. but with the SB700 it wasnt as but yet the numbers showed what I wrote. will do a short video as well showing how it was done.
I will do the SB700 and SB900 again soon in the evening to make sure what happened was accurate. im pretty confident in the 5600III specs. yongnuo noted the GN for this and said it was in line with the nikon flagship. really, a best bang for buck manual flash you could ever want to buy. build is fantastic, very fast to recycle very strong. win win.

A weak or damaged capacitor can only hurt, it cannot tremendously boost performance. :) Something was happening that you were not controlling.


Yeah, I also have a Yongnuo YN-565EX (includes TTL and remote wireless), and it is an incredible bargain. Not quite a Nikon regarding some minor features or warranty, but its performance is great, more power than a SB-700 for 1/3 the price.

The tests should be carefully controlled. All the flash specifications specify their output level (Guide Number). We already know what to expect. Procedure makes small variations, but any large variation should be questioned. If widely different than specified expectations, it should attract attention.

Carefully measure and control and publish your distance, so you can know how reasonable, and others can see it too.

For example, if GN is 111.5 (feet) for the specified zoom and power level used, then GN = distance x fstop.
If fstop is 16.9, then distance should be 111.5 / 16.9 = 6.6 feet.
Or, if distance is 6.6 feet, then metered fstop should be 111.5 / 6.6 = f/16.9

Metered value can be affected by side reflections in a small room (adding to the direct value), etc.
 
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rocketman122

Senior Member
No, not weird, or rather, very specialized purpose.

In manual flash mode, you simply set full power or 1/4 power, and that is what the flash does, period. It is up to the camera to set ISO and aperture to appropriate usable values. The flash could not care less, it just flashes at the specified power level.

But some flashes (SB-900, SB-800) have the automatic A mode (Auto mode, non-TTL auto). In this mode, the flash is self-metered, and has a front sensor that reads back its own flash, and it terminates the flash power level to be appropriate to the light result it sees. Works rather well, but the sensor is not through the lens, it sees and meters a different area than the lens or camera sees. But to know what the appropriate target exposure goal is, it has to know which fstop and ISO the camera is using, so it can compute the same exposure. CLS flashes obtain these numbers automatically from the hot shoe, but if the flash is off camera (no hot shoe), this A mode has to have a menu to set the ISO and fstop, so it can compute exposure. Just for this A mode (non-TTL auto). And for any GN mode, or manual mode distance scale too, but those don't work if not on the hot shoe.

But Manual or TTL flash has no use for it, does not need to know fstop or ISO.. All they have to do is flash at the power level setting specified for them to use.



But what mode did they recognize off camera? Did you verify it? Such tests need to carefully control all variables. I don't exactly suspect this, but something was strange, unreasonable results for SB-700, and other than procedure, this is all I can think of. To be certain, I would set their menus directly to FX mode.
If the SB-700 was doing DX zoom, it would almost fully explain it.



A weak or damaged capacitor can only hurt, it cannot tremendously boost performance. :) Something was happening that you were not controlling.


Yeah, I also have a Yongnuo YN-565EX (includes TTL and remote wireless), and it is an incredible bargain. Not quite a Nikon regarding some minor features or warranty, but its performance is great, more power than a SB-700 for 1/3 the price.

The tests should be carefully controlled. All the flash specifications specify their output level (Guide Number). We already know what to expect. Procedure makes small variations, but any large variation should be questioned. If widely different than specified expectations, it should attract attention.

Carefully measure and control and publish your distance, so you can know how reasonable, and others can see it too.

For example, if GN is 111.5 (feet) for the specified zoom and power level used, then GN = distance x fstop.
If fstop is 16.9, then distance should be 111.5 / 16.9 = 6.6 feet.
Or, if distance is 6.6 feet, then metered fstop should be 111.5 / 6.6 = f/16.9

Metered value can be affected by side reflections in a small room (adding to the direct value), etc.


Im always in awe how much you know regarding flash, because its not typical. many pros I work with dont know much about light and do a trial and error to get results. its sad that many dont take the time to understand flash and are quite scared of it and have a hard time with it. but flash is complicated and there is a lot to learn. I would say that the difficulty is understanding light/flash but also understanding how to mix it with the camera. thats a different discussion

yes the thyristor. when Dttl was the main balanced tech they had a few years back many pros I worked with preferred A thyristor over the ttl or Dttl options. they said they got much better results. its possible, as the digital world was just starting to bloom with the D200.

I did change it now to FX in the SB900. the Sb700 was FX. I will recheck it as it is set now. yes, very unreasonable, almost leading me to believe that for sure I messed something up. when I first saw it I went to the flash to make sure I set it correctly. I will also make a video showing how it is set for each flash.

what I meant about the SB900 is that its been used so much, that maybe the reason is weakened capacitors that are a bit tired...?

for those needing just basic features, like TTL, manual, strobostic, and CLS (which I hate) the 565 and 568 are just fantastic. I beat on my 560III and it just says thank you sir may I have another. and with a smile HAHA

Im not really good with these calculations. its not that I cant understand it, but when I see numbers I lose patience and have to walk away. my brother is a real mathematician. an elite programmer/developer and was a regional chess champ. he has a very binary head. hes the brains, im the art.

regarding the distance, why cant I just use them all at 1m (or 2 or 3 or whatever) and just fire them and test what their Fstop is? im not looking for a scientific test. I basically want to see what it can pump out at full power at the 35mm mark at iso 100 at 1m. is this wrong? I just dont have a straight line that long. and when I did the test, there was just one spot led light for ambient so I could see what I was doing but it 10' away.
 
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WayneF

Senior Member
Im always in awe how much you know regarding flash, because its not typical. many pros I work with dont know much about light and do a trial and error to get results. its sad that many dont take the time to understand flash and are quite scared of it and have a hard time with it. but flash is complicated and there is a lot to learn. I would say that the difficulty is understanding light/flash but also understanding how to mix it with the camera. thats a different discussion

Don't get that started, but it really does not seem awesome to me. In one way, flash is just a light we add. Yes, if we don't know nuthin', and can only use point&shoot, sure, it all must seem very hard and mysterious. Things happen, and we have no clue why. But if we understand exposure (how and why and when to use ISO, aperture, shutter speed), then daylight and continuous light is not very mysterious at all. Even the reflective meter can be handled if we think about it. :)

<cynical view> Yes, it does require we think about it a bit (which point&shooters seem unwilling to even attempt to do). It seems right that our grandmothers can use their little cameras by just pushing the button, but avid amateurs and esp pros charging money for their skills, ought to actually acquire a few skills. :) Adding flash is just one more light. Yes, flash is a little different than continuous, and it really won't ever actually be point&shoot, but its easy to understand how to use it... If we care to try. It seems most won't even try.

My point of reference is that this is also true of my own experience. I went very many years, active, buying lots of bulk film, acquired some dark room skills, etc, imagined I knew a lot, but without ever actually knowing anything about the camera or the process. I could parrot back some facts, but it was not working knowledge that I had learned to use. Back then, cameras had no menus, the only controls were shutter speed and fstop, but I really knew nothing about it except how to center the camera meter. I simply was an unthinking novice for very many years. Then one day, I finally started wondering, how does this stuff actually work? And paid more attention and thought a little bit. Then, regarding the basics, it all became easy, the light came on, things changed. With really very little effort. The difference was, there was finally some effort.

yes the thyristor. when Dttl was the main balanced term they had a few years back many pros I worked with preferred A thyristor over the ttl or Dttl options. they said they got much better results. its possible, as the digital world was just starting to bloom with the D200.

The flash A mode was pretty good stuff, and it can still work well, like it always did, but TTL has become todays option. The main difference is that the flash has a wider light sensor, often around 35mm lens wide, used for any lens in every situation. And the camera TTL does offer more, to meter the same view the lens sees (be it wider or more narrow), and adds features like Spot or Matrix metering, and provides the computer to add features like flash balanced with ambient, etc.

I did change it now to FX in the SB900. the Sb700 was FX. I will recheck it as it is set now.

That's backwards from my expectations, but its always good to know for sure.

what I meant about the SB900 is that its been used so much, that maybe the reason is weakened capacitors that are a bit tired...?

No way to know without knowing the distance you used, comparing it to what the manufacturer says it should do. If you were are at 1 meter, it did not do well, but no way for me to know, you didn't say. Flashes will of course meter at a weaker level if at a greater distance.

regarding the distance, why cant I just use them all at 1m (or 2 or 3 or whatever) and just fire them and test what their Fstop is? im not looking for a scientific test. I basically want to see what it can pump out at full power at the 35mm mark at iso 100 at 1m. is this wrong? I just dont have a straight line that long. and when I did the test, there was just one spot led light for ambient so I could see what I was doing but it 10' away.

No, it is not wrong at all, just not fully useful. To compare, obviously all flashes have to be at exactly the same distance, but how hard is it to carefully measure and set and tell that distance? Because, if unknown, there is no way to evaluate if it is reasonable result or not. Me, I like to know more details so I can wonder about more things. :) So you can use any reasonable distance, but I'm suggesting to know that distance, to spend a minute verifying the distance between flash and meter is some specific number (like 2.0 meters). Some specific number adds meaning in regard to flash power.

All the flash manuals have a detailed Guide Number chart, typically at the back of the manual. This is how direct flash works.

SB-900 says (page F-19) at full power, ISO 100, FX mode, 35mm zoom, the GN is 111.5 (feet) or 34 (meters). I use feet, but I suspect you use meters. Same result, so long as we are consistent. GN in feet is always 3.28 times GN in meters (because that's how many feet in one meter).

That means that proper exposure of direct flash is expected to be:

1 meter .... GN 34 / 1 = f/34
2 meters ... GN 34 / 2 = f/17
3 meters ... GN 34 / 3 = f/11.3 (BTW, what we round off to call f/11 is actually precisely f/11.3... matters in GN computations).

If you're at 2 meters and meter it 1/3 stop off, that's not much surprise, things vary, esp our procedure.
If you're a full stop off, that is something to wonder about.
If you don't tell us distance, it's not much to know, and we have no clue what it means.

The SB-700, 800, and 900 have the GN mode which uses this chart (and which can be pretty accurate). The hot shoe sees the ISO, aperture, and zoom, and then we can enter the measured subject distance, and the mode will set manual flash power level to deliver the correct exposure for that distance, from this chart. This mode has advantage of being independent of the subjects color (white dress, black dress, etc), which tends to fool TTL metering.

Elaborating because I assume you are interested:

For example, without taking any picture, just put the SB-900 on the hot shoe (at some ISO, fstop/ zoom - any values, not extremes of anything - just don't change anything).

Then in flash GN mode, enter 2 meters or 10 feet, or some distance, or simply just use the distance it already shows.

What distance does it show?

Then try same everything with the SB-700.

What distance does it show?


These two distance numbers show the expected power relationship that Nikon designed into the flashes. They won't be equal numbers for a SB-900 and SB-700.

The way it works, if you enter closer distances, it reduces the flash power to be correct for that distance.
If you enter greater distance number, it increases flash power until it reaches maximum, and won't increase any more.

If the distance was reasonable for the scene, and if you did take two pictures here (of the same scene), they should compare well as to proper exposure.

Whatever those distance numbers are... multiply the distance by the fstop number, which will be the Guide Number.
It should approximately match the number in the GN chart for same ISO and zoom values.

For example, my SB-800... ISO 100, zoom 35mm, says at maximum distance of 12 feet at f/10, so GN is 12 x 10 = GN 120.
The chart in the manual says full power at 35mm is GN 125. There is rounding involved, so this is pretty close to actuals, not a concern.

Hope that is of any interest.
 
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WayneF

Senior Member
I, for one, would like to see how this test was performed. It's not an unreasonable request.

Maybe not, but this actually seems one case when the words are better than a picture. :) There are many words the picture could not show.

As you are probably aware, incident meters are aimed away from the subject... aimed at the light (or camera) from subjects position, and they meter the actual light level incident on the subject. This is independent of the subject, and is only about the flash power reaching the subject.

This is in contrast to reflected meters which are aimed at the subject, and meter the light reflected from the subject, such as it can be reflected. The subject introduces variables which trouble our exposure.

Rocketman explained his setup, with the light meter attached to a fixed stand aimed at the flash. He said meter was ISO 100 and flash was full power and 35mm zoom. Actually, I realize now he did explain that the meter was exactly one meter from the flash, and somehow I had missed that. So now I wonder why the SB-900 did not meter f/34 and the SB-700 did not meter f/28? (expected from Guide Number table). Something is still unexplained, something is not as expected.
But otherwise, this meter reading should be the correct camera settings (ISO and aperture) to take a flash picture of any subject at the same light meter position and distance, in that situation, with that flash power at same location. Just how flash meters work.

Other than settings, that procedure seems very straight forward, I don't know what a picture could add. You put the meter in front of the flash, and trigger the flash. :)
 

Steve B

Senior Member
Did you measure the distance from the mount or from the front surface of the flash? As you said earlier they are all shaped a little different. At only one meter it wouldn't take much to skew the results although that does seem a little extreme for a difference that was probably less than an inch.
 

WayneF

Senior Member
Did you measure the distance from the mount or from the front surface of the flash? As you said earlier they are all shaped a little different. At only one meter it wouldn't take much to skew the results although that does seem a little extreme for a difference that was probably less than an inch.

I don't know. Hard question. :) Focus distance is measured from the focal plane mark near the rear of the camera (where the film or sensor is). When and if the camera is ever concerned with flash distance (D-lens distance), this is the only number it knows. Several zoom lenses get it quite wrong though, so there are worse problems. :)

But light is measured from its source, which technically ought to be the flash tube, but I tend to think of it as the front lens of the speedlight. Comparing flashes seems OK if consistently done. I can see that softboxes and umbrellas are different though, front fabric is obviously not the source.

I agree, I doubt it is quite that critical for the speedlght. One meter is about 40 inches, two inches is 5%. 2 or 3 meters seems much more reasonable for human subjects (for perspective), so an inch or two shouldn't matter much.

The difference in 72 and 70 inches is 0.08 stops.
 
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Browncoat

Senior Member
Comparing flashes seems OK if consistently done.

That's just the thing. If there's going to be a benchmark and accurate results, it needs to be documented...hence my request for the pics. I read in one of his responses that we was going to post pics or a video, or something. Was just requesting to see it.
 

rocketman122

Senior Member
That's just the thing. If there's going to be a benchmark and accurate results, it needs to be documented...hence my request for the pics. I read in one of his responses that we was going to post pics or a video, or something. Was just requesting to see it.


thats fair . you are right. I just hate the "pics or it didnt happen" that specific statement fires me up. seems to be thrown around very easily. next time say can you post a short vid showing how it was done?

I will do. and reply to you as well wayne. im tired as hell. give me a bit to get it done.
 

Browncoat

Senior Member
You need to take my brand of sarcasm and dry humor in stride, man.

And when I say "in stride", I really mean with a lot of liquor. Or roll up a blunt, whichever gets the job done.
 

aroy

Senior Member
When I started using flash about 35 years ago, my camera was fully manual with an incidence meter. You set the ISO on the dial and then read the speed/aperture combination. The flash I used was fully manual (Nissin). It had a table of distance verses aperture, so you set the aperture depending on the distance. That is all. Later I got a Braun same facility with higher guide number. Now I have a couple of SB800s.

So even today I have a fair idea of how to use the flash in manual mode - necessary as the D3300 uses manual mode with older MF lenses. That is why I was interested in knowing how the flashes behave at long distance.
 
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