430EX II shots blown out when shooting in manual

I suppose it seems 'odd' that the flashgun only has 7 stops of power adjustment when you expected more, but it's big brother only has one more stop (although as it starts higher it's probably similar power).

7 stops is quite a lot though and I'd expect to be able to make a balance somewhere with that. But at 1/80 and ISO 800 - that's allowing for some very low light to balance with. For reference, the flashgun tells you the suitable distance in metres for a given ISO and aperture setting and you can 'lose' a lot of that power by other means.

I don't know quite what you're trying to achieve, but either bouncing the flash or using gels on it is probably the answer to your problem.
 
RichieRich said:
Thanks for the reply. Sorry, but I don't get the 1/40,000 sec bit.

Also, if Canon thinks that a certain power is available with ETTL I'm not sure how the logic of restricting it in manual stacks up. After all, most people have discovered this issue when switching to manual during a shoot, only to find that images are totally blown out.

Imagine if you bought a camera body and you discovered that it wouldn't let you set the ISO to anything lower than 1600 when setting it manually! I think that most people would be disappointed.
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The point about 1/40,000sec is that it's extremely brief and getting close to the limit of reliable control. There are also colour shifts as the light is more blue at very short durations.

Anyway, here are some real figures I just got - 580EX at 1/128th power (virtually identical to 430EX at 1/64th) gave correct exposure with subject exactly 23in from flash, f/5.6 IS0100. It's hard to imagine wanting to go any lower than that, on the normal side of macro, and also the lens was shading a lot of the image at that range too.

I'm not getting the problem here. Flash runs to minimum power output in manual as specified - anything else is a bonus. If you want less brightness than that, then stick something over the flash. Sheet of normal white paper will lose you another stop or two, or use ND gels.
 
Phil V said:
I suppose it seems 'odd' that the flashgun only has 7 stops of power adjustment when you expected more, but it's big brother only has one more stop (although as it starts higher it's probably similar power).

7 stops is quite a lot though and I'd expect to be able to make a balance somewhere with that. But at 1/80 and ISO 800 - that's allowing for some very low light to balance with. For reference, the flashgun tells you the suitable distance in metres for a given ISO and aperture setting and you can 'lose' a lot of that power by other means.

I don't know quite what you're trying to achieve, but either bouncing the flash or using gels on it is probably the answer to your problem.
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Actually, I will respond because that was useful info - thanks Phil.
 
HoppyUK said:
The point about 1/40,000sec is that it's extremely brief and getting close to the limit of reliable control. There are also colour shifts as the light is more blue at very short durations.

Anyway, here are some real figures I just got - 580EX at 1/128th power (virtually identical to 430EX at 1/64th) gave correct exposure with subject exactly 23in from flash, f/5.6 IS0100. It's hard to imagine wanting to go any lower than that, on the normal side of macro, and also the lens was shading a lot of the image at that range too.

I'm not getting the problem here. Flash runs to minimum power output in manual as specified - anything else is a bonus. If you want less brightness than that, then stick something over the flash. Sheet of normal white paper will lose you another stop or two, or use ND gels.
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If you have the chance could you do a quick experiment - with the settings you describe try increasing the camera's ISO until the image starts to become blown out. At that point switch to ETTL and see if it's still blown out. If your flash behaves like my 430EX II you'll find that you can go about 3-4 stops further with the ISO when running ETTL before the image blows out when compared to manual - although I suspect that 1/128 may be a stop dimmer than the 430EX II's minimum power of 1/64.

Thanks for the feedback - I'll set up with the figures you indicated too and perform a few test shots.
 
RichieRich said:
If you have the chance could you do a quick experiment - with the settings you describe try increasing the camera's ISO until the image starts to become blown out. At that point switch to ETTL and see if it's still blown out. If your flash behaves like my 430EX II you'll find that you can go about 3-4 stops further with the ISO when running ETTL before the image blows out when compared to manual - although I suspect that 1/128 may be a stop dimmer than the 430EX II's minimum power of 1/64.

Thanks for the feedback - I'll set up with the figures you indicated too and perform a few test shots.
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Okay, I just shot a grey card for exact exposure and colour, and married up the 1/128th power exposure exactly with E-TTL at 27in. Then with E-TTL, increased the ISO as you asked, and it held correct exposure at 2.6 stops higher. At three stops and higher it just over exposed more.

At anything less than 1/128th equivalent power in E-TTL, exposures started to get a bit erratic, but not by much. Maybe half a stop max variance, ie +/- 0.25 stops. Colour changed too, fluctuating on the RGB histogram, but again not by much - nothing to complain about really, perfectly usable. (BTW, if you shoot with AWB, Canons correct the colour according to flash power. I used daylight WB.)

So you're right, it looks like there is usable E-TTL power control a couple of stops at least below the min manual setting (Canon 580EX gun). I'm less sure how useful this is, or why anyone should want to complain about it really. And manufacturers always play safe with these things with generous tolerances, so with this in mind, I thought I'd try another on my 580EX guns - one that I know is a b it different at least in its HSS output. Anyway, in the same comparison, that one started over-exposing above 2.0 stops below 1/128th power.

PS When I started doing these comparisons, I noticed a strange thing - the colour was varying up and down the frame. Bit of a puzzle, but it could only be some kind of ambient light pollution, then I noticed the hall light was on with a small fluorescent bulb, shining through the door. It was a few meters away and it hardly seemed possible, but turning it off fixed the colour shifts. Things like that are normally totally invisible at normal x-sync speed, but it jut goes to show how low the flash brightness was.
 
HoppyUK said:
Okay, I just shot a grey card for exact exposure and colour, and married up the 1/128th power exposure exactly with E-TTL at 27in. Then with E-TTL, increased the ISO as you asked, and it held correct exposure at 2.6 stops higher. At three stops and higher it just over exposed more.

At anything less than 1/128th equivalent power in E-TTL, exposures started to get a bit erratic, but not by much. Maybe half a stop max variance, ie +/- 0.25 stops. Colour changed too, fluctuating on the RGB histogram, but again not by much - nothing to complain about really, perfectly usable. (BTW, if you shoot with AWB, Canons correct the colour according to flash power. I used daylight WB.)

So you're right, it looks like there is usable E-TTL power control a couple of stops at least below the min manual setting (Canon 580EX gun). I'm less sure how useful this is, or why anyone should want to complain about it really. And manufacturers always play safe with these things with generous tolerances, so with this in mind, I thought I'd try another on my 580EX guns - one that I know is a b it different at least in its HSS output. Anyway, in the same comparison, that one started over-exposing above 2.0 stops below 1/128th power.

PS When I started doing these comparisons, I noticed a strange thing - the colour was varying up and down the frame. Bit of a puzzle, but it could only be some kind of ambient light pollution, then I noticed the hall light was on with a small fluorescent bulb, shining through the door. It was a few meters away and it hardly seemed possible, but turning it off fixed the colour shifts. Things like that are normally totally invisible at normal x-sync speed, but it jut goes to show how low the flash brightness was.
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Thanks very much for taking the time to do that. Your comments and what you've observed suggest the following:

1) My initial observations seem to be broadly correct.
2) I need to invest more time in learning how to use the 430 EX in order to get the most out of it.

While I wouldn't regard myself as being a novice photographer, I clearly have a lot to learn about flash photography - to the point that I find the prospect of doing so quite exciting, as sad as that may sound. I've just purchased this book after having watched a presentation by the guy on YouTube - it should help.

http://www.amazon.co.uk/Speedliters-Handbook-Learning-Craft-Speedlites/dp/032171105X

It will be interesting to see if the minimum power constraint becomes an issue once I've learned the ins-and-outs of using the flash properly. If it does I'll simply use an ND filter.

I did contact Canon by the way - I will let you know what they say if and when they get back to me.

Thanks for all the helpful responses everyone.
 
HoppyUK said:
So you're right, it looks like there is usable E-TTL power control a couple of stops at least below the min manual setting (Canon 580EX gun). I'm less sure how useful this is, or why anyone should want to complain about it really.
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As I explained above, since I shoot concerts, I want to use the lowest amount of fill possible in very small venues. I want just a hint of flash and leave in some venue lighting to keep the shots looking like a live music shot. I know this is possible through eTTL but even at 1/64 power, it's impossible to get what I want. That, to me, is a good reason to complain about the lack of flexibility.
 
You're welcome RR.

Flash is a fantastic tool, opens up a whole new world of picture taking. And that's a really good book :thumbs:
 
shufflemoomin said:
As I explained above, since I shoot concerts, I want to use the lowest amount of fill possible in very small venues. I want just a hint of flash and leave in some venue lighting to keep the shots looking like a live music shot. I know this is possible through eTTL but even at 1/64 power, it's impossible to get what I want. That, to me, is a good reason to complain about the lack of flexibility.
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Okay, but losing brightness is really easy. Zoom back, flip down the wide panel, stick a Stofen diffuser cap on it, or a piece of white paper, or an ND gel.

Getting more power is a heck of a lot harder.
 
shufflemoomin said:
As I explained above, since I shoot concerts, I want to use the lowest amount of fill possible in very small venues. I want just a hint of flash and leave in some venue lighting to keep the shots looking like a live music shot. I know this is possible through eTTL but even at 1/64 power, it's impossible to get what I want. That, to me, is a good reason to complain about the lack of flexibility.
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I had a similar situation when I discovered the problem. I was filming a skateboarder doing a trick in a warehouse which was pretty well lit. I set up with the camera on manual, including the flash at 1/64 to give me a base power to work from - at the point where I'd take the photo the skater would be just a few feet from me, traveling along a rail. Unfortunately the images were completely blown-out. ETTL was fine, but it would vary as the skater would suddenly appear. It essentially didn't give me the power which I required consistently. Still, after I've learned a bit more I'll try again - perhaps with some kind of filter over the flash in necessary.
 
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