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View Full Version : Exposure bracketing for HDR w/Nikon D50???




Veritas&Equitas
Feb 18, 2007, 11:28 AM
Hey all. Like I admitted before, I'm a total noob with my D50, but I'm learning! I have a tripod, and my D50, but I'd love to get the HDR shot...

So...do I have to take like 5 separate pictures with the differing levels of exposure (-2, -1, 0, +1, +2), or can I take one with all the different levels? Also, should I use Photomatix or Photoshop to alter the dynamic range once I have all the 5 shots? I guess I'm just looking for a little advice, and maybe a pointage to a tutorial? I've looked, but no one has a *simple* answer to my question about the exposure...thanks!



compuwar
Feb 18, 2007, 11:55 AM
Multiple exposures which is what the camera's auto bracketing function will do.

Try these:

http://www.harzergruben.de/DRI/dri.htm

http://www.luminous-landscape.com/tutorials/hdr.shtml

ksz
Feb 18, 2007, 12:42 PM
I'm not familiar with the D50, but the D200 has an auto bracketing feature that lets you dial in a "spread". One of the available spreads is -2, -1, 0, +1, +2. Next, set the continuous shooting mode to High Speed. Finally, compose your shot and hold the shutter down continuously and count down until the 5 frames have been shot, then release the shutter. Hence, only one press of the shutter release button!

Veritas&Equitas
Feb 18, 2007, 12:52 PM
Thank you both, that is exactly what I was looking for, and what I needed!

Coheebuzz
Feb 19, 2007, 04:48 AM
The problem with most DSLR's with the exception of a few higher-end models is that they only allow you to take 3 shots in different exposures, thats not enough for digital since the dynamic range in each photo is much less than film.

You can change the range after you've shot the first 3 shots but you'll need a really sturdy tripod so you don't move the camera after you pressed some buttons on it. If anyone knows of a good technique to do this please share!

By the way here is another tutorial (http://stuckincustoms.com/?p=548) on using Photomatix, i think this guy goes too far sometimes but he also has some unbelievably stunning shots.

beavo451
Feb 19, 2007, 07:57 AM
You can change the range after you've shot the first 3 shots but you'll need a really sturdy tripod so you don't move the camera after you pressed some buttons on it. If anyone knows of a good technique to do this please share!


Use Nikon Camera Control and shoot in tethered mode. You can change the settings on the computer without touching the camera.

compuwar
Feb 19, 2007, 10:14 AM
The problem with most DSLR's with the exception of a few higher-end models is that they only allow you to take 3 shots in different exposures, thats not enough for digital since the dynamic range in each photo is much less than film.


This is not true. Digital cameras can have 10-11 stops of dynamic range- see for instance:

http://www.clarkvision.com/imagedetail/dynamicrange2/

For a comparison of digital vs. both positive and negative film dynamic range.

Best-case, you can get 7-9 stops from film- even an old S2Pro has 8.9 stops, putting you 1/10th of a stop out from the best result you can get on film. Slide film has about 5 stops of DR, B&W film up to nine, though prints seem to top out generally about about 8 stops.

Here's how it stacks up:

Slide film: 5-6 stops
Color print film: 5-7 stops
B&W film: 7-9 stops

Digital SLR: 7-11 stops

At base ISO, the D50 that the original poster has has between 7.36 and 10.7 stops of dynamic range depending on if you're shooting in high quality mode or not. At 10.7 stops *in color* it's handily beating out the 7 stops of DR that Kodak Royal Gold 200 exhibits.

Now, you could possibly argue that the top and bottom two stops on digital are too noisy to be considered, but then you'd *still* be at the 7 stops you're getting with color print film and so you'd still be ok.

2/3rds of the way down http://www.imaging-resource.com/PRODS/EOS1DS2/1DS2IMATEST.HTM is a listing of digital camera DR by image quality setting.

Since you actually can change settings on a digital camera locked down on a sturdy tripod with a good head and then reshoot, you're pretty much ahead of anyone other than someone shooting large format or medium format with a removable back who's then post processing digitally.

Coheebuzz
Feb 19, 2007, 01:02 PM
Use Nikon Camera Control and shoot in tethered mode. You can change the settings on the computer without touching the camera.

Yes am aware of that, i have a Canon 400D by the way and it comes with the EOS Utility that does the same thing. This is good only under studio conditions though. What would work best is a remote control that lets you change the AE range but i don't know if such a thing exists.

This is not true. Digital cameras can have 10-11 stops of dynamic range- see for instance...

I wasn't aware of that, thanks for the link! I always thought that one of the advantages of film over digital is the higher dynamic range but now it seems this myth is busted.

So to summarize, will a good tripod be sturdy enough to allow me to enter the menu of the camera and change the auto bracketing range without shaking or moving it? Also what kind of tripod head offers the best stability, 3 axis or ball head?

compuwar
Feb 19, 2007, 05:47 PM
I wasn't aware of that, thanks for the link! I always thought that one of the advantages of film over digital is the higher dynamic range but now it seems this myth is busted.

So to summarize, will a good tripod be sturdy enough to allow me to enter the menu of the camera and change the auto bracketing range without shaking or moving it? Also what kind of tripod head offers the best stability, 3 axis or ball head?

Mostly you find sharpness tests as the main film/digital comparison, so it's easy to miss the work that's been done outside of that.

The heavier the tripod, the more stable (but the more of a PITA to carry around.) Berlbach (sp?) wooden ones are the sturdiest ones I've personally used, though my current Gitzo 1548 is probably almost 2 pounds lighter and seems about as stable. As long as you can lock it down, any head should work, though cheaper ball heads tend to not lock down well (and I mean $150 and under!) in my experience. You still have to be very careful about movement though. It may help to have a tripod that has a hook for hanging from the center column where you can put several pounds of weight. The usual tripod stability rules apply- legs extended as little as possible, with as few sections as possible, and camera on a plate or if you have a center column, it all the way down. Small and cheap tripods probably won't have enough stability- I used to shoot large format, where you have to insert the film holder after you focus on the ground glass, so I'm used to huge tripods and locking things down (I'd probably even skip the tripod head if I were being super-critical and could level the legs by themselves.)

Also, a hand pushing down on the top of the body (assuming that doesn't move it) may help stabilize the body as you make the change. Truthfully though, I've never tried, the D2x has enough brackets to not worry about reshooting :)

Veritas&Equitas
Mar 8, 2007, 12:56 PM
At base ISO, the D50 that the original poster has has between 7.36 and 10.7 stops of dynamic range depending on if you're shooting in high quality mode or not. At 10.7 stops *in color* it's handily beating out the 7 stops of DR that Kodak Royal Gold 200 exhibits.

Compuwar, is there any way you could explain how I do this specifically with my D50? I can only get 3 different exposures like he was talking about...I don't know how to get that many different exposures...thanks for the help!

ChrisA
Mar 8, 2007, 01:20 PM
I've looked, but no one has a *simple* answer to my question about the exposure...thanks!

That's because the answer is "It depends." You need to take a set of exposures that capture the dynamic range of the scene or at least of the parts of the scene you want to capture. The most typical case is you have a foreground that is dark and a very bright sky and you want to capture details in both. so what you'd do there is take one exposure using matrix automatic mode. and then one each of the sky and foreground using whatever your spot meter says is best for each of those.

Or if you don't want to use the spot meter just use a minus compensation until the blinking in the blinking highlights display stops blinking and then take a plus 2 shot for the shadows.

I've never seen the value of automatic bracketing. It saves you from having to press the +/- button and turn a thumb wheel but turnning on the auto-bracket feature requires just as much effort.

The better solution to the common bright sky, dark foreground problem is to use a neutral density gradient filter. You will get better results but there are other cases (night scenes with mixed lighting) that only making a composite of multiple exposures can solve.

compuwar
Mar 8, 2007, 01:25 PM
I've never seen the value of automatic bracketing. It saves you from having to press the +/- button and turn a thumb wheel but turnning on the auto-bracket feature requires just as much effort.



1. It saves you from having to set settings, possibly moving the camera.
2. That depends on the camera, with the D2x, you just hit the bracket button with your left hand as you press the shutter, no need to remove your eye from the finder even.

compuwar
Mar 8, 2007, 01:40 PM
Compuwar, is there any way you could explain how I do this specifically with my D50? I can only get 3 different exposures like he was talking about...I don't know how to get that many different exposures...thanks for the help!

It looks like with the D50, you'll have to bracket manually to go more than 2/3 of a stop in each direction. The easiest way to do that is to meter with the camera and look at the recommended aperture. Set the camera in aperture priority mode and select that aperture. Then move up and down the scale taking shots at either every stop, every other stop, or every third stop depending on whatever testing you do's results. On a good tripod and/or with good software to align the shots you should be ok as long as you're careful.