Opinions on exposure bracketing

[ShooterJ]

Hey all,

Just wanted to throw this out and see what people think in general. When shooting with the intention of creating an HDR image, what do you find the best number of exposures to be? I've heard some say 2 exposures, one for sky and the other for foreground.. I've heard 3 exposures (use AE Bracket) and I've heard some people talk about taking many exposures because it gives a larger range (not sure how I feel about that).

Would I be correct in assuming that the more exposures you shoot, the more ghosting you're going to have in an image and therefore not quite as clean/sharp? How many exposures do you take for an HDR? What's worked best for you?

Thanks all!

 

[Gavjenks]

I find that 3 exposures at about 2 stops apart is plenty in most cases. Sometimes even less distance. Depends how dramatically contrasty the scene is and what sort of lighting you are adding, if any.

If it's very contrasty (like a night scene with big lights pointed right at across a river or something), and if there's not much around to be ghost-y (like trees near the camera), then you could benefit from 5-7 exposures, potentially. Why not?

Also, even if there is something potentially ghost-y nearby, some software lets you custom define ghosting areas, such as photomatix, so you could avoid issues still, at the cost of more post processing time (hopefully youre only shooting a few HDRs though on a shoot, not like 50)

 

[ShooterJ]

Thanks for the reply Gavjenks..very informative. And no worries, I think HDR fits in some cases.. but most of the time I don't shoot for it. I think it's an awesome way to process, when it's needed. I still have a lot to learn about it though.

 

[robertwatcher]

The odd time that I have use the technique - I have used 5 frames. My buddy who is a serious 360 degree HDR shooter for animation and gaming, uses 9 frames and prefers his Nikon camera because it provides that ability without having to bracket in sections or shoot manually. I've never seen any ghosting in his shots.

 

[tirediron]

I generally estimate the dynamic range of the scene and expose once for each stop of range; doesn't mean I have to use all of the exposures in the final merge, but IMO, having more information is never a bad thing, and digital film is cheap; shoot lots!

 

[ShooterJ]

Great information all around .. thanks everyone. :thumbup:

 

[Gavjenks]

For those of you out there with Canon cameras: the FREE custom firmware "magic lantern" allows you to set up auto bracketing for 9 exposures. You might even be able to do 11 or more, I don't remember. It loads onto your camera from a memory card and creates extra menus and stuff in your camera with a lot more options. Not just HDR bracketing, but things like built in intervalometers, etc.

It does not void your warranty, and can be put on just about any camera they sell, even many of the ones no longer marketed.

 

[hirejn]

Most people just guess and have no idea what's necessary for HDR, which is why they bracket the heck out of shots that need only two or three frames. The average camera captures at least 5 stops, conservatively, so three shots gives you 15 stops. Some cameras can safely capture 7 stops, so that would give you 21 stops in three shots. It's not often you would need more than that. You can keep guessing or you can use a light meter that will tell you the dynamic range of the scene and give you the middle value. You can then take one exposure at each end and one in the middle, or more, depending on the range of the scene. But this is of little use without knowing the exact dynamic range of the camera, which the Sekonic L-758 can help you figure out. The simple answer is like everything else in photography HDR comes down to understanding light. There's no one correct answer. Understand dynamic range. Use a hand-held spot meter. Otherwise you're guessing to some degree.