high dynamic range imaging · taking photos for hdri works best with a tripod take multiple photos...
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High Dynamic Range Imaging
Kent Messamore
8/13/2009
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What is High Dynamic Range Imaging?
Normal Cameras can capture a dynamic range of 6-9 stops
By merging multiple exposures for highlights, midtones, and shadows using HDR software, dynamic ranges of 10-15 stops can be captured in 32 bit images
HDR images however, cannot yet be viewed as Monitors and Printers cannot display this dynamic range and 32 bit images
Tone mapping is used to compress the dynamic range into viewable form
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Example from my porch
If exposed for outside the window, inside is too dark
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Example from my porch
If exposed for inside the porch, outside is too light
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Example from my porch
HDR Image allows for correct exposure for both
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Taking Photos for HDRIWorks best with a tripod
Take multiple photos
Focus should be same (manual focus)
ISO and F/stop should be same
Vary either speed or aperture to change exposure between shots
Limit as much as possible anything moving between shots as this will create ghosts in the final image.
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Without a tripodIt is possible to do HDRI without a tripod
Use Auto Exposure Bracketing along with continuous shooting mode, i.e. three shots in one second, all with different exposures
Brace yourself as much as possible or rest your camera on something.
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3 Exposures, Tripod, AEB
f/5.6 1/2000 ISO 320
f/5.6 1/8000 ISO 320
f/5.6 1/500 ISO 320
+&- 2 Stops
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From Bridge to PhotoshopTools -> Photoshop -> Merge to HDR
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From Lightroom to PhotoshopRight Click -> Edit In ->Merge to HDR
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Can adjust white point. Click OK
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Processing in PhotoshopSwitch to 8 or 16 bits
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Four different ways to process.See if you like one or the other.
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Local adjustment with curves
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There are better ways to Tone Map than Photoshop. Save 32 bit file as Radiance.HDR
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HDRI ApplicationsPhotomatic (most popular)
Photomatic Pro ($99)- Includes HDR Generation and Tone Mapping. Includes Lightroom Plug in. Free Trial
Photomatic Pro Plus – Includes Photoshop Plug in
Dynamic HDR - Generation & Tone Map - $55
FDRTools - $61- Generation & Tone Map
HDRShop - $400 – Kitchen sink
Picturenaut – Free (Doesn’t Support RAW Files)
PhotoAcute – HDR Generation only (handles ghosts well)
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Photomatic Pro (using Photoshop HDR image)
Tone Map
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Photomatic Pro Adjustments for Tone Mapping
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Basic Adjustments
Strength - Start High. At end, lower to taste
Color Saturation - Much overused. Use restraint
Luminosity - Controls how bright shadows are
Light Smoothing - Smoothes transitions between tonal areas. High is more like a photograph; low more like a drawing (posterized)
Microcontrast – affects contrast in small detail
White Point – Sets white upper limit
Black Point – Sets Black lower limit
Gamma – Sets image overall brightness
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Color & Detail AdjustmentsTemperature – makes warmer or cooler
Saturation Highlights – increases saturation
Saturation Highlights – increases saturation
Micro-smoothing – Smoothes transition between tonal zones. Set high more like a photograph; Low more like a drawing.
Highlight Smoothing – affects highlights
Shadows Smoothing – affects shadows
Shadow Clipping – clips blacks
Presets – Can save preset settings
Initiate Tone Mapping process
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Other HDR Images
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HDRI
End