HDR Photography guide from Akron Camera Club

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A good guide to HDR

Text of HDR Photography guide from Akron Camera Club

  • How-To-HDR: Photography

    Akron Camera ClubNovember, 2011

  • Overviewo Create HDR images

    throughn Camera techniquesn Photomatix softwaren Photomatix softwaren Photoshop techniques

    o Layerso Masks

    n Plug-inso TopazLabs

    n Texturizing

  • o HDR High Dynamic Range Imagingn Techniques that allow greater dynamic range of luminance between the

    lightest and darkest areas of a photo to be viewed on standard media, ie. Paper, computer screen, projector.o Helps to prevents areas from being blown out, as well as preserve

    detail in shadows.

    n This wide dynamic range allows HDR to represent intensities found in real scenes from sunlight to starlight. found in real scenes from sunlight to starlight.

  • Computer HDR Renderingo Computer renderings for

    games and movies utilize HDR to give a realistic view of the worldworldn This is the effect we want

    to recreate in our photos

  • o In photography, dynamic range is measured in EV (exposure value,)

    Dynamic Range

    Device Stops Contrast

    Dynamic Range

    (exposure value,) known has stops, between the brightest and darkest parts of an image that show detail.n An increase in 1 EV stop is

    doubling the amount of light captured.

    Computer LCD 9.5 700:1

    DSLR Camera 11 2018:1

    Print Film 7 128:1

    Human Eye 10-141024:1 -16384:1

  • HDR Photo Creationo To capture a greater range of light,

    there are several techniquesn Use multiple images with differing

    EVs that will later be merged into one EVs that will later be merged into one image

    n Use one RAW image, split into separate images with differing EVs and later merged into one image

    o Tip: HDR creation generates a fair amount of noise, which can be removed through noise reduction software

  • HDR creation generates a fair amount of noise, which can be removed through noise reduction software

  • Multiple Photographso Multiple photographs can be taken with any

    camera that allows manual over and under exposure

    o Take photos in succession, including both under and over exposed EVs, (ex. -2,0,+2 stops).n Use Aperture priority mode to keep the areas of

    blur the same.n This can be done manually with a tripod or

    exposure braketing (auto bracketing) if your camera has it

    n The scene must remain as similar as possible to avoid ghosting or movement shadows created when the multiple images are merged.

  • Take photos in succession, including both under and over exposed EVs, (ex. -2,0,+2 stops).

    o -2 EV 0 EV +2 EV

  • The scene must remain as similar as possible to avoid ghosting or movement shadows created when the multiple images are merged.

  • Single Photographo Since RAW allows a data

    capture range larger than can be displayed, then a single RAW image can be converted into 3 photos converted into 3 photos (-2,0,+2) and saved as separated .jpg or TIFF files.

    o This is very useful for spur-of-the-moments or movement photos where 3 exposures are near impossible to get.

  • Softwareo Photomatix- widely used for

    tone mapping and HDR generation n Photoshop plug-in or

    standalone programstandalone programn Starting at $39, Indefinite

    free trial with watermarko Free versions

    n Picturenaut, FDRTools Basic, Essential HDR Community Edition

    n See References for site links

  • Photomatixo Select your photos, use align

    photos if multiple photos were taken (hand-held or even tripod) and reduce ghosting if there was movement in the scene, then processprocess

    o This creates a new photo that is all the combined data in a viewable way. It will look very odd and nearly unusable until tonemapped.n Tip: Viewable without

    tonemapping on HDR monitors, now only $49,000 for 37 set

  • This creates a new photo that is all the combined data in a viewable way. It will look very odd and nearly unusable until tonemapped.

  • o Tone map- Technique that maps one set of colors to another in order to approximate the appearance of HDR on a medium that has more limited dynamic range.

    o This allows fine tuning an image through slidersn Here is where you can change aspects

    of your photo based on tasten Remember: There is no right way to

    set these sliders, but there is a wrong way

    Try to get the majority of the o Try to get the majority of the image balancedn Small imperfect areas can be corrected

    in layers with the original in photoshop

    o Remember: HDR is about light and contrast not color and oversaturationn Tone map changes the look of an

    image, try looking natural or make a dramatic statement with different settings

  • o Settings General Suggestionsn Strength ~ 100%n Color Saturation Use conservativelyn Luminosity Painterly Effect Farther

    right = less contrast. Halo problems can be helped by moving to the right

    n Microcontrast Changes small details and fluctuations in color

    n Light Smoothing Important slider, controls HDRness of the photo.controls HDRness of the photo.o Left = psychedelico Right = more natural

    n White/Black Point move till bell curve rests inside the graph

    n Other sliders have uses but I rarely touch them

    n Once you have your settings you can save them as a custom setting

    n Process your photo and save it as a .jpg

  • Photos after Photomatix, nice, but could use some tweeking to have more impact