Black on the bottom of photos (flash related)

[kat]

I know I know this but I'm not 100% sure. And my googling just infuriates me..so lets go to the best source.

When you take shots (flash on) and you get that black on the bottom of the photo, what causes that? How to avoid that?

Thanks
kat

[Iguanasan]

Do you have a long lens on? Generally, it's happened to me that I was close to the subject and the lens shadows the scene when the flash goes off because it's on top of the camera. Pull the camera back, get the flash off the camera, or turn the flash off altogether.

It might be something else but that's the only thing I've run into so far.

[kat]

K..that is what I thought as well. But I wasn't too sure if it was something else with that as well.

Thanks!

[Richard]

I sometimes experience dark bands when using my wireless flash triggers if I go above 1/200.

If you exceed your max flash sync speed, the shutter curtains can start to show banding on the image because not all of the image sensor is exposed to the flashes light.

[Mad Aussie]

Further to Iggy's comment ... Long lenses often have long hoods. Take the lens hood off if you are using one and see if that stops it Kat.

[Andrew]

If it's only on flash then check your sync speed and back off to 3/4 speed and shoot a test. Also check the sync method (front curtain, slow, rear curtain) and associated settings in the manual for your particular camera.

[kat]

Well, it's actually my sis who was saying she needed to send her camera in because she kept getting this. Right away I thought it was the flash as she believes that is when it does happen (and it's not all the time). She uses auto so I don't think the camera would be off on its setting to have that happen (although I could be wrong on that). I'm not to sure of the trend of when it happens. I have told her to start taking heed to it.

[Marko]

Andrew and Richard have pegged this. This sounds like a classic sync speed issue. Basically you have exceeded the maximum sync speed your flash can sync with your camera.

The exif data on any frame where the band shows will tell you what your shutter speed was for any given shot. Googling your flash's sync speed or checking the manual will tell you what the sync speed is. If the shutter speed is faster than the sync speed your problem is now solved. All you have to do is never exceed that speed and you will never see those bands.

[kat]

Andrew and Richard have pegged this. This sounds like a classic sync speed issue. Basically you have exceeded the maximum sync speed your flash can sync with your camera.

The exif data on any frame where the band shows will tell you what your shutter speed was for any given shot. Googling your flash's sync speed or checking the manual will tell you what the sync speed is. If the shutter speed is faster than the sync speed your problem is now solved. All you have to do is never exceed that speed and you will never see those bands.

Would that happen if your camera is set to auto and it's the camera's flash? Wish I had the camera in front of me.

[Iguanasan]

Would that happen if your camera is set to auto and it's the camera's flash? Wish I had the camera in front of me.

In the case of my Canon Rebel XSi it won't let me go higher than 200, or lower than 1/200 depending on how you look at it. I just can't change the settings to get the on board flash "out of synch".

[Marko]

Would that happen if your camera is set to auto and it's the camera's flash? Wish I had the camera in front of me.

can't be sure about that - but just try it next time u have your camera.

[kat]

LOL..it's not my camera. :P I do know she uses her longer lens and usually close ups of the kids. I told her to throw on her other lens and shot with them for a bit and see if she notices it. Hmm..maybe an excuse for a visit..hahah.

thanks everyone

[Mad Aussie]

Definitely don't rule out the lens hood thing Kat. I know the flash sync is an obvious choice, but I've been fooled by the lens hood on close up shots before.

Some digital camera's won't use above the sync speed anyhow. You choose a higher shutter speed but it defaults to the sync speed when the flash is selected.

[Richard]

If everything is on Auto, then the lens hood does indeed sound like a distinct possibility, especially when using the cameras "on-board flash"

[Iguanasan]

Here's a possible solution :) Use a Pringles Can as a Cheap Diffuser for Macro Photos (http://www.petapixel.com/2011/04/26/use-a-pringles-can-as-a-cheap-diffuser-for-macro-photos/)

Did you ever find out for sure what it was? I'm curious?