I think im still not understanding how my flash works

[Robin Usagani]

Hah.. Nice Mo. Like always.. you read it somewhere and bam.. you are 100% certain and everyone else is wrong. You need to fix your attitude. Yes, you and I are like oil and water.. thats why i removed you from my AIM and my facebook. Couldnt stand you anymore.

 

[MohaimenK]

Oh okay, so it was in ETTL mode?

That is what I'm not certain about. I wish I had the original, then I could have read the exif data. Unfortunately these were uploaded on FB private folder so it deleted all exif data

 

[o hey tyler]

Mo-

FYI, if you had your flash in ETTL mode set to +1/3, there's no way that your "test" proved anything. The flash will adjust the output power of the flash in ETTL mode when the ISO is changed. In order for your test to see if ISO increases flash exposure would needed to be done on manual at a constant power setting, with constant shutter speed and aperture. Where the only adjustments that were made would be to the ISO on your camera. Similar to what you did in your "test", but it would actually yield results.

 

[Robin Usagani]

LOL.. ETTL.....

 

[MohaimenK]

Mo-

FYI, if you had your flash in ETTL mode set to +1/3, there's no way that your "test" proved anything. The flash will adjust the output power of the flash in ETTL mode when the ISO is changed. In order for your test to see if ISO increases flash exposure would needed to be done on manual at a constant power setting, with constant shutter speed and aperture. Where the only adjustments that were made would be to the ISO on your camera. Similar to what you did in your "test", but it would actually yield results.

Yup! I agree with you 100% there. That's why I didn't want to give you an exact answer incase I had it set to that. Maybe I had it at TTL with with FC +1/3? Or maybe I was in M mode? Either way I have to re do the test. I love doing tests :mrgreen:

 

[Robin Usagani]

Whoever said with ETTL the flash goes lower than 1/128 has no idea what they're talking about. Sorry its just the wrong information.

When you need to squeeze every very bit of power from your Speedlite, switch it to Manual mode and set it to 1/1. In E-TTL, the Speedlite uses a bit of its power for the pre-flash. By switching to Manual, you eliminate the pre-flash and send all the juice straight out in one big burst.


Conversely, if you are shooting in Manual at the lowest power setting and still have too much light, switch over to E-TTL. The pre-flash will suck up a bit of power and thereby reduce the intensity of the flash. The change will be small, but it might be just enough.


and no Kundalini, if the subject is away from background then the shutter speed/iso won't matter UNLESS shutter speed is ridiculously low and ISO is extremely high. When using flash, the flash will be same intensity on the subject at 1/125 shutter speed vs 1/160 shutter speed. The flash doesn't doesn't stay open enough to matter. Same with 400 ISO or 800 ISO. ONLY thing will change is the ambient light being darker vs brighter. (please don't start an argument with me saying I don't know what I'm talking about)

Is this your statement or you read it somewhere?

Conversely, if you are shooting in Manual at the lowest power setting and still have too much light, switch over to E-TTL. The pre-flash will suck up a bit of power and thereby reduce the intensity of the flash. The change will be small, but it might be just enough.

 

[Village Idiot]

Whoever said with ETTL the flash goes lower than 1/128 has no idea what they're talking about. Sorry its just the wrong information.

When you need to squeeze every very bit of power from your Speedlite, switch it to Manual mode and set it to 1/1. In E-TTL, the Speedlite uses a bit of its power for the pre-flash. By switching to Manual, you eliminate the pre-flash and send all the juice straight out in one big burst.


Conversely, if you are shooting in Manual at the lowest power setting and still have too much light, switch over to E-TTL. The pre-flash will suck up a bit of power and thereby reduce the intensity of the flash. The change will be small, but it might be just enough.


and no Kundalini, if the subject is away from background then the shutter speed/iso won't matter UNLESS shutter speed is ridiculously low and ISO is extremely high. When using flash, the flash will be same intensity on the subject at 1/125 shutter speed vs 1/160 shutter speed. The flash doesn't doesn't stay open enough to matter. Same with 400 ISO or 800 ISO. ONLY thing will change is the ambient light being darker vs brighter. (please don't start an argument with me saying I don't know what I'm talking about)

Is this your statement or you read it somewhere?

Conversely, if you are shooting in Manual at the lowest power setting and still have too much light, switch over to E-TTL. The pre-flash will suck up a bit of power and thereby reduce the intensity of the flash. The change will be small, but it might be just enough.

Because that seems to be wrong as well.

 

[Robin Usagani]

especially because if you shoot at 1/128 power, ther should be 127/128 power left

 

[MohaimenK]

VI, here's the link. "Speedlighting Learn Canon Flash Photography"

Deciding Between E-TTL and Manual – Part 1: Manual Flash | Speedliting

Unless now you're going to say "Mo you probably host that site"

 

[Overread]

Guys read the question and lets stop with the cheapshots at each other


pretty please :hugs:

Basic answer to your question, the camera and flash are communicating with each other to produce the shot at set parameters. This communication provides a range of maximum power down as it sees fit.

You are not communicating with the flash. You are imputing designed parameters, full power, half power, 1/4 power etc. It would be excessively costly to put and external control for a human to dial up any power setting. That is what a light meter is for. Set two of the three parameters of the exposure triangle and it calculates the third parameter to get a proper exposure.

Hmm this is interesting since using flash manually is often quoted as "the" way to shoot flash; yet here you say what I've guessed, but never had confirmed, that the flash in ettl can select different powers to those that the photographer can in manual mode. (which goes some way to explaining why flash power output isn't recorded in EXIF data -least to my understanding).

For me I prefer camera in manual and flash in ttl/ettl. The camera then adjusts the flash output to the needs of the shot. Shutter speed then plays a part in the depth of the ambient light/background. The camera/flash combo can make that determination easily inside the programed parameters.

When not in ttl/ettl mode I am using a flash meter to get the right exposure in a full manual mode.

The only way to have a true manual variable power would be a rheostat of some sort. The issue then becomes one of duplication. With distinct power settings two flashes set to the same setting should put out the same amount of light. How do you get the exact settings if it is totally variable rheostat setup? You have no controlled settings except full power and no power. Everything in between is a guess.

I guess my confusion comes from not knowing enough about electronics and capcitors and such - but if they can break the power level into fractional stages why can't they just increase the number of factional stages? We already have the full power drop down from 1:1 to 1/2, 1/4 etc... and in some units can further break those down into +/- 0.3 and 0.7 blocks between the full stop change. So how come they can't go lower than the 1/128 power limit if the flash itself is capable of firing accurately at lower powers?
Is it a case of hardware being too limited to ensure a consistent output at those lower power levels or is it just one of those software based limits that we have for no real reason?

 

[kundalini]

.......and no Kundalini, if the subject is away from background then the shutter speed/iso won't matter UNLESS shutter speed is ridiculously low and ISO is extremely high. When using flash, the flash will be same intensity on the subject at 1/125 shutter speed vs 1/160 shutter speed. The flash doesn't doesn't stay open enough to matter. Same with 400 ISO or 800 ISO. ONLY thing will change is the ambient light being darker vs brighter. (please don't start an argument with me saying I don't know what I'm talking about)

Up to this point, my contribution to this thread was directed towards Schwettylens. I made no comment on backgrounds, shutter speed, flash intensity, flash duration, specific ISO settings, ambient light (whether bright or dark).

I don't want to, nor do I need to start an argument with you. You seem to be handling this marvelously all on your own.

 

[Derrel]

Wow, this thread is very,very confusing...almost impossible to read...virtually useless as a reference. Maybe another thread is in order? The manual fractional power setting of 1/128 is a very low power, FIXED output; automatically-regulated power outputs are basically "stepless", and are determined by the camera, or the flash unit's, built-in light metering systems. At extremely close ranges, an automatically metered flash pop can be just the teensiest, tiniest, weakest,briefest little "pip" of flash output...but if the subject moves two feet away between shot 1 and shot 2, in an E-TTL metering mode, the flash's output could easily increase substantially....but at Manual 1/128 power, the flash output will always be 1/128 power.

And Mo, as far as the test photo segments you posted: the highlight densities do not show much change, but look at the gray tone values and their shifts....also...when showing comparisons like that, when the flash-to-subject distances are allowed to change, the results are, well, suspect.

 

[Overread]

also...when showing comparisons like that, when the flash-to-subject distances are allowed to change, the results are, well, suspect.

Gah I well know those pains when trying to do macro with manual flash powers and either handholding the flash or having a moving subject. Even small differences in the distance/angle could make big changes to the light on the subject.
I keep considering getting one of those Benro tripods (the ones that lock/unlock their legs all at once) just to hold the flash for those occasions.

 

[MohaimenK]

And Mo, as far as the test photo segments you posted: the highlight densities do not show much change, but look at the gray tone values and their shifts....also...when showing comparisons like that, when the flash-to-subject distances are allowed to change, the results are, well, suspect.

Yes sir! I will have to redo the test and make sure I use a tripod and use someone to do the test. Also I'll have to make sure it's in M mode and not TTL that way it'll be constant light coming. I will test from ISO 100 until ISO 800. I know from 100 to 800 there will be a difference but I am more interested in the lower ISOs to see how much of a change it is. Does that sound right?

 

[Overread]

And Mo, as far as the test photo segments you posted: the highlight densities do not show much change, but look at the gray tone values and their shifts....also...when showing comparisons like that, when the flash-to-subject distances are allowed to change, the results are, well, suspect.

Yes sir! I will have to redo the test and make sure I use a tripod and use someone to do the test. Also I'll have to make sure it's in M mode and not TTL that way it'll be constant light coming. I will test from ISO 100 until ISO 800. I know from 100 to 800 there will be a difference but I am more interested in the lower ISOs to see how much of a change it is. Does that sound right?

Review your histogram (in camera or in computer)as you do the test. Each time you put your ISO up by one stop - either from 100 to 200 or from 800 to 1600 you'll see the histogram show a one stop increase in light on the shot (for areas directly affected by the flash light of course).
That is of course whilst keeping flash power output, aperture, shutter speed and distance of flash from the subject the same for each exposure and only varying the ISO between shots.