using a flash at a motorbike show

Seamus

Hi folks,

I'm looking for advice. I will be going to a motorbike show at the end of the month. I have a 420 ex flash. I have read the threads on using a flash and have experimented with the flash. My question is

is p mode using flash enough to freeze motion when taking pictures of people? or should I use manual and set the camera to 1/200 f8 or similar setting?

If anyone here has taken photographs at a motor show perhaps they would be kind enough to advise me.


thanks,

Shay.

Shay Stephens

If you are shooting flash, the best mode to be in is manual. Anything else is a compromise between accuracy and ease.

If you must use an auto mode, make sure the camera *does not* choose the shutter speed. Keep the shutter speed at or below the x-sync speed at all times when using flash or you will get poor exposure results.

Shay (The other - other - white meat)

Seamus

Shay Stephens wrote:

If you are shooting flash, the best mode to be in is manual. Anything else is a compromise between accuracy and ease.

If you must use an auto mode, make sure the camera *does not* choose the shutter speed. Keep the shutter speed at or below the x-sync speed at all times when using flash or you will get poor exposure results.

Shay (The other - other - white meat)

Hey brother Shay,

I have been trying out manual mode with speed at 1/250 and aperture around f5.6 to f8. The flash seems to cope fine with these settings. The p mode settings are always 1/60 and f4-f5/6. That seemed very slow to me. .

thanks for the help,

I will post a few pics after the event and let you know how I got on.


Shay, (the fat bald one)

Shay Stephens

If the flash were providing a substantial portion of the exposure (i.e. more than 50%) then the flash can freeze the action because the flash output is so fast compared to the shutter speed. The more ambient light you have, the more motion blur will be noticable.

However, if the flash is contributing 50% or less of the overall exposure then a slow shutter speed will show motion blur on fast moving subjects. A possible solution is to increase the ISO setting to get faster shutter speeds or increase the power output of the flash (not always practical or possible).

If in need, use a higher ISO, noise is better than motion blur most days ;-)

Shay (not a result of cloning)

Seamus

"If the flash were providing a substantial portion of the exposure (i.e. more than 50%) then the flash can freeze the action because the flash output is so fast compared to the shutter speed. The more ambient light you have, the more motion blur will be noticable.

However, if the flash is contributing 50% or less of the overall exposure then a slow shutter speed will show motion blur on fast moving subjects. A possible solution is to increase the ISO setting to get faster shutter speeds or increase the power output of the flash (not always practical or possible).

If in need, use a higher ISO, noise is better than motion blur most days ;-)

Shay (not a result of cloning)"

Thanks for the help, Shay. If you don't mind another stupid question, when you are taking pictures at weddings the light would be quite dim? Roughly what settings would you use?

Thanks

Shay (the stupid one)

Shay Stephens

Usually around f/2.8 - 1/60 - ISO 800 to 3200 (depending on circumstances)

Sometimes I go down to 1/30th and slap on the 50mm f/1.8 but then I am having a really hard time focusing, so I usually start getting grumpy at this level ;-)

Shay (now fortified with vitamin R)

Thanks for the help, Shay. If you don't mind another stupid question, when you are taking pictures at weddings the light would be quite dim? Roughly what settings would you use?

Thanks

Shay (the stupid one)

Seamus

Thanks Shay, I appreciate the help ,



Shay (who has run out of stupid questions to ask)

Higgmeister

Seamus wrote:

However, if the flash is contributing 50% or less of the overall exposure then a slow shutter speed will show motion blur on fast moving subjects. A possible solution is to increase the ISO setting to get faster shutter speeds or increase the power output of the flash (not always practical or possible).

Hi Shay,
I know this is late, but better late than never. If the above statement is the case and you are going to get some motion blur (not always a bad thing), then look into setting the flash to "second curtain sync". What this does is it opens the shutter and the flash will fire at the end of the exposure verses the beginning of the exposure. This gives the motion a more natural appearance as the motion is behind the flash instead of in front of it.

Also, I've never tried this yet, but newer cameras and flashes have a high speed sync. This allows you to take a flash shot with a higher shutter speed than the x-sync speed. The flash manual (I have the Sigma 500) says that the output is not as strong so some experimenting would need to be done. I'm not sure of the 420EX has that, but I'm thinking it might.

Hope the shots come out OK,
Chris

Seamus

Thanks Chris, the 420 does have high speed sync. I have been trying different settings and will keep a good eye on the histogram. I will post some pics after the show to let you know how I get on, the show is on the 27th.

Shay.