Viewing 26 posts - 1 through 26 (of 26 total)
  • Camera flash questions
  • molgrips
    Free Member

    Messing about with this lovely new (to me) flash, for which I have not yet paid, I’m a little confused. Flash is in full native communication mode, both camera and flash are Olympus. I select auto ttl, and with my Sigma F1.4 lens it seems to default to widest aperture and everything is very over exposed.

    So I put the camera in A mode and adjust the aperture. The distance reading on the flash changes, so it knows what aperture is selected, but when I take pictures at different apertures they seem differently exposed. They SHOULD all look broadly the same, no? Is that not the whole point of TTL mode?

    Cougar
    Full Member

    Is there a TTL-2 mode?

    I’ll be watching this with interest, I understand all the camera settings now but my flash baffles the crap out of me.

    raymeridians
    Free Member

    I struggle to make TTL flashes work with the camera in anything but manual mode. Set the aperture how you want it, pick a shutter speed below sync speed and use the exposure compensation on the flash to get the exposure right is how I do it.

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    molgrips
    Free Member

    Have you tried similar on yours?

    One thing I like about Olympus is that their manuals are really detailed and give you practical explanations of what each thing does.

    5thElefant
    Free Member

    Have a look at shutter sync speed. No idea what the Olympus does if you’re asking it to do things beyond the sync speed but it could do seemingly odd things.

    goldfish24
    Full Member

    I would agree that TTL should be maintaining the exposure as you say, but it won’t be perfect.

    Not a direct answer to your question, but anyone looking to get the best out of their flash must read this: http://strobist.blogspot.co.uk/2006/03/lighting-101.html

    Usefully, he advocates manual setting rather than TTL.

    molgrips
    Free Member

    The camera knows the flash is on and sets shutter speed to the minimum flash speed which is set as 1/60. It’s always this indoors. You can override it up to the max flash sync speed, 1/180.

    5thElefant
    Free Member

    Have you tried an Olympus lens? Just to rule out Sigma incompatibility.

    raymeridians
    Free Member

    I suspect what you’re seeing is that when you’re in one of the programme modes the camera is metering for ambient light and just using the flash for fill-in – that’s what Canon’s do. Depending on how much light is available that can lead to some interesting shutter speeds. Why that gives you inconsistent exposures, no idea, unless it’s picking speeds that are too fast (so you’re relying on luck to get the flash into the scene) or you’re shooting before the flash has had a chance to recharge.

    If you haven’t see in, this book has some nice examples:
    http://software.canon-europe.com/files/documents/FlashWork_EN.pdf

    MrSmith
    Free Member

    read the manual 🙄

    molgrips
    Free Member

    I have…

    bigyinn
    Free Member

    Not Olympus, but from what I’ve read its often easier to manually set everything rather than use TTL. Which is odd, as when ever I used TTL flashes on my film camera it exposed pretty well.
    TTL flash on DSLRs seems to have gone backwards.
    Probably a little more RTFM + trial and error will get you there.

    MrSmith
    Free Member

    have you tried it at -1/3 or 2/3?
    ETTL always seems to be very bright and looks much better as a fill. i very rarely use on camera flash but i would usually set the aperture/shutter to the ambient and have it in aperture or shutter priority so i could adjust it a little and then have the flash at a stop or so under and ETTl. (this was with canon though).

    inverjoe
    Free Member

    Is the difference you are seeing not a difference in ratio between the ambient light and fill light, although all being correctly exposed. At f1.4 there will be a LOT of flash in the picture. Personally i would only open it up that wide if i was bouncing it off a wall or ceiling.

    molgrips
    Free Member

    I had to go to -3.0 to get it to look normal with the Sigma. There’s been some suggestion that as Olympus don’t make any lenses bigger than F1.4 that some stuff doens’t work very well if you have a Sigma lens that does it.

    Is the difference you are seeing not a difference in ratio between the ambient light and fill light, although all being correctly exposed.

    Hmm.. checking the historgrams they look the same but shifted left or right.

    It does seem to work better with an Olympus lens but the one I tried would only do f5 at the comparable focal length so less of a significant impact.

    i very rarely use on camera flash

    Yeah I was basically experimenting. Bounced, everything seems to be perfect and shots end up looking just like they do to my eye.

    molgrips
    Free Member

    Ah, I think I’ve figured it out.

    Either the flash has a minimum amount of light it can do, or a minimum it can use for TTL. In TTL mode there’s a distance range displayed on the screen, and it seems it’s that that doesn’t seem to work with the wider apertures. The flash doesn’t seem to be able to work lower than a certain threshold, and at f1.4 there’s just too much, but the distance display doesn’t tell me to move further away.

    If I do move further back than what it says, it seems to work ok.

    bigyinn
    Free Member

    Just stop the lens down a bit, unless you’re looking for a really shallow DOF?

    molgrips
    Free Member

    I can, just wondered what was going on.

    mikey-simmo
    Free Member

    Never heard a flash not be able to work with the widest app, normally it’s limited to shutter speed. If I use my flash in manual mode it still produced more light on 128th full power than it does on the minimum TTL output.
    Never had much success with the A settings, just stick to manual and TTL.
    The flash should be ablt to Quench the flash at the widest App. Have a google to see if your alone in suffering this. either that or you’ll have to dial down the flash compensation (if you have it), generally I have my TTL set down at -2 for no reason I can find, it just works better.

    molgrips
    Free Member

    generally I have my TTL set down at -2 for no reason I can find, it just works better.

    Seems to match my experience, at least at wider apertures.

    slowoldman
    Full Member

    Sorry can’t help. My last flash was powder on a tray.

    mikey-simmo
    Free Member

    TTL is good in parts, good conditions, light contrasting subjects you’ve half a chance. Stick it in manual and it improves dramatically.

    convert
    Full Member

    To be honest I have only got results from owning a flash of which I am proud when used off the body, with the built in flash in commander mode (Nikon) and the flash set to manual. And even then only normally with a reflector too.

    TTL just seems to take too much control away, like putting an SLR into auto.

    molgrips
    Free Member

    Stick it in manual and it improves dramatically.

    Yeah but then you’ve got a bit of experimenting to do – or at least I do. Not very useful when taking wedding party documentary snaps.

    When taking photos of my wife’s craft work, everything’s in manual. Can’t imagine taking this much time over every photo, there just isn’t the time.

    footflaps
    Full Member

    Never used Canon, but on Nikon I always have to turn the flash down as it just seems to over expose by default (this is on their top end pro kit). I can’t say I’ve tried to understand TTL, there are whole books just on Nikon TTL, which suggests it’s complex to say the least!

    captainsasquatch
    Free Member

    Never used TTL here either, always manual. I understand what the camera does, I don’t undestand what the software writers do.

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