Assuming you have constructed or obtained the appropriate cable to interface your camera to the DS and loaded the OCC_Bracket app on your CF card, we can begin shooting HDR sequences.

HDR Bracket Shooting with the Nintendo DS


The DS software will make a few assumptions about the settings on your camera.

Set the camera to Bulb mode and Manual aperture! The DS will control the exposure length by a variable length closure of the camera’s manual shutter port.

The camera should be set to manual focus. This is not mandatory, though if auto focus is used, a suitable amount of time should be added to each shot to make sure focus has been found. We never use autofocus in shooting HDR’s, it’s simply good practice to know where the lens is focused, and that each shot has consistent settings. In our time spent in film sets observing some great DOP’s, we’ve never heard anyone say “rolling...autofocusing...and action!”

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Upon launching the bracket software, we’ll see these two screens on the DS.
On the left you see is the main settings. By pressing START we’ll see the panorama calculator (right). This screen is mainly used to configure an attached pano motor, however it might be useful if one is doing manual camera moves.

Note that the lower half of these screenshots is shown on the touchscreen of the DS, hence the lower half is where you input setting. The upper half is non-interactive and acts as status screen.


Interactive Interface Guide
memory mirror_lockup noise_reduction radio_buttons interval step_back stop_steps stop_intervals lock preview_ticks center_slider sequence_duration planned remain remaining_time current_shot

Memory Speed


If shooting with an older camera, or slow memory card, setting the memory speed slider may be necessary. Most cameras can handle continuous shooting, though Canon Rebels, the Sigma SD-14, or cards like the Eye-fi might need a little cushion. If you see that the DS is triggering shots while the camera is still saving the previous picture, add a little delay by moving the slider left.

Mirror Lockup


Sets the desired mirror lockup delay. This is a subjective setting. Although intended to wait for internal camera vibrations to settle, it can be adjusted to compensate for the general stability of the tripod and head. We like to travel with the lightest carbon-fiber tripod, so we adjust the mirror lockup delay to account for a greater amount of vibration.

This setting does not tell the camera to use Mirror Lockup. ML must be enabled or disabled in your camera’s menu functions before shooting. Many cameras do not have a reflex mirror, so the setting is not needed. If no ML is used, this setting should be set to 0.00 seconds.

Noise Reduction


In-camera noise reduction is a mixed blessing. It allows new cameras to shoot at high ISO and low light, but requires a lot of processing power. The 5D Mark II, for example, will take twice the exposure time to shoot an image, not noticeable for quick shots, but a five second exposure takes ten seconds to shoot and process before saving.

The noise-reduction setting simply informs the bracketing program if you’ve turned on or off NR functions in your camera. It does not change the setting itself, it is merely a way to tell the DS that it needs to take extra time after each exposure to allow the camera to compute the NR filter.

Merging multiple images ameliorates the effect of sensor noise, so you may wish to try turning it off in order to speed up HDR shooting in dark settings. the difference between a five minute shot and a ten minute delay to compute NR for a five minute shot is significant, and some hold the opinion that there are more controllable ways to deal with noise; taking a single dark-frame shot per session, for example, to be subtracted downstream in the processing workflow.

Radio Buttons


A number of radio buttons act as a quick way to further control shooting.

The MT setting (Manual Trigger) offers the option to stop between each shot an await a button press before continuing.
For longer shots, my timing isn’t always perfect. The 2X button takes a second “insurance” shot for every exposure to increase the chance of success.

The REV function reverses the order of the shots, switching from fastest-to-slowest to slowest-to-fastest. This was added when it was noticed that shots after sunset can be slightly different depending on the shot order, as the brightest images became darker as the twilight progressed.

The WU setting (Wake Up) fires a throw-away shot at the beginning of a bracket sequence. This is mainly used during intervalometer time-lapse shots, when the camera might enter sleep-mode.

The SS setting (Screen Saver) simply turns off the display backlight during a shoot, to save battery life. The DS is designed to be used for several hours before charging, so it is usually moot.

The PM setting (Pano Mode) starts a motor-controlled panorama, more info can be found in a separate document.

Stop Steps


The Stop Steps setting is changed by touching the number inside the ring. It is currently programmed to switch between 3, 5, 7, and 9 stops of bracketed exposures, with an even number above and below the metered shot.

It’s the photographer’s choice, the amount of bracketing needed hinges on the physical conditions of the scene, although I have also found that metering a scene is sometimes inaccurate, and adding more stops of padding allows for choosing the correctly exposed images later. It is not uncommon to find one or two extra shots of nearly black or white-out images.

Stop Intervals


Below the Stop Steps function is the Stop Interval setting. It can currently be stepped between 1/3, 1 and 2 stops of stepping between shots. The effect of this setting is a trade off between the number of exposures and the amount of time it will take to complete the sequence. The effect can be most easily judged by watching the arrowheads and tick marks on the upper screen, these represent the actual shots to be taken during a shot sequence.

Middle Exposure Slider


The slider function across the top of the lower screen quickly sets the metered exposure or “middle shot” of the HDR sequence. This exposure should generally mark what an ideal non-bracketed, non-HDR image’s shutter speed would be set to.

The DS touch-screen pen is used to slide the diamond across the scale, and the rest of the sequence will automatically adjust around this setting. In a pinch, when the DS pen is misplaced, this setting can be changed with a finger and a little patience. The test buttons below can be used to judge if the exposure outcome is as desired.

Preview Tickmarks


The arrowheads on the upper screen represent the actual exposures to be taken. This preview comes in handy when you change the Stop Steps or Stop Interval settings.

Also note that you can change the middle exposure with the slider right underneath (which happens to be shown on the touchscreen).

Lock Settings


If the settings are made and you know you’ll be moving the camera, tripod, or maybe rotating the rig for a panorama, the Padlock setting is used to ensure that the sequence doesn’t accidentally change. We’ve use the DS to document dozens of props and objects on a movie set, for example, and use the padlock to make all of the sequences consistent to one another.

Planned Shots


The Planned readout confirms the number of images to be taken.

Sequence Duration


The Sequence Duration readout estimates how long a HDR bracket sequence will take to complete. It acts as a fast way to see the effects of all of the various settings on exposure time, and good way to tell if using things like 2X insurance will simply take too long for a given situation.

Walk Away Delay


The Walk Away delay setting determines how much time you’ll have to hang the DS on the tripod and walk away so that you don’t interfere with the shoot by bumping the tripod, or moving on flexible floors.

Intervalometer


The Intervalometer can be used to take continuous HDR time-lapse sequences, although I’ve yet to find an efficient means of processing the number of images that result from shooting so many exposures.

For a more traditional intervalometer, use the stand-alone interval shooter DS program, which allows for rapid single setting sequences.

Current Shot


During shooting, the Current readout will tell you what shot is being taken, i.e. “1/2 second” etc.

Remaining Time


If you are using the intervalometer, the Interval Remaining readout describes the wait before the next sequence begins, otherwise the Sequence Remaining display offers up the remaining amount of time before the current sequence finishes.

Keep in mind that these readings do not update during a shot, because the DS’ CPU is being used to carefully control shot timing. Since the longest shot is usually the last, and the timer doesn’t update during this shot, there might be a shorter waiting period than displayed.

Remaining Shots


The Remaining readout simply shows how many more shots need to be taken before an HDR sequence is finished.

When it reaches zero, a vocal announcement indicates that the camera is ready to move on to the next position. We tried to make it as loud as possible, though the DS has limited speaker size and volume.

Shooting



To begin shooting, hold the left and right shoulder triggers on the back of the DS and place the DS in a stable location before stepping back. If you hang the DS from the tripod using the wrist strap, watch out for pendulum motion that can have a subtle effect on the image quality.

Once you take your “haul” back to the office for processing, you’ll be ready to process the images into HDR, and we’ll discuss some DS specific techniques in another document.

Here’s some crazy over-processed tone-mapped good/badness taken with the Nintendo DS Phat and an Olympus E-P1 with 17mm pancake. I set the tripod and walked away as the DS shot a seven image bracket, while I discussed the niceties of fighter jet restoration with a technician at the Boeing factory in Everett, Washington.

Highslide JS

If you wish to modify the software to suit your own needs or establish presets for a particular camera, have a go at the source code.