Retouching

Understanding Tone Mapping - Via Macphun

Here's another from my series of Educational blogs with Macphun!  Be sure to check them all out on https://aurorahdr.com/blog


What's the first image that pops into your mind when someone says HDR? For most people, they think of dark, grungy, over-saturated images with halos surrounding every hard edge in the photo. The truth is, that's not actually HDR, but in fact, a form of Tone Mapping.

Understand HDR first!

To understand Tone Mapping we need to first explain HDR. So what is HDR exactly? Well High Dynamic Range images simply mean that the photo has more dynamic range in it than any camera (currently) can capture in one single shot. To be able to create a real HDR image, you have to take 3 or more photos at different exposure values. 

 

Typically one frame will be at a proper exposure, then the rest are overexposed and underexposed at various increments to let you capture the details in the brightest highlights and the darkest shadows. Then these images are merged together to create a 16-32 bit file.

As I've explained in a few other blog posts and videos on our YouTube channel, most every camera available on the market currently has a sensor in it that can record information with a very specific dynamic range, (somewhere between 5-14 stops of light), which is FAR LESS than what the human eye can perceive. Therefore we combine these bracketed exposures together to create an HDR image.

If you try to take a high contrast shot with a single exposure you typically end up with either completely blown highlights, or all details lost in the shadows.

When you've taken a proper mix of exposures (under, balanced, and over), and merged them with an HDR software app, you're left with a relatively flat and low contrast image. This is where tone mapping comes into play.

What is tone mapping?

It's the process of converting the tonal values of an image from a high range to a lower one. For instance, an HDR file merged from multiple images with a dynamic range of 100,000:1 will be converted into an image with tonal values ranging from around 1 to 255.

Why do we want to reduce that tonal range so much? Well the reason is simple. Most standard display devices (and printers) can only reproduce a low range of dynamic values (between 100 or 200:1 or lower). The goal of tone mapping is to reproduce the appearance of images having a higher dynamic range to fit/display properly on standard display devices, thus keeping the image looking realistic.

The algorithms that tone mapping use to scale the dynamic range down attempt to preserve the appearance of the original image captured by breaking the information up into two categories: global and local.

Global operators map each pixel based on it's intensity and global image characteristics. The process ignores its spacial location or if it's in a dark or light area. Using global only tends to leave you with a flat non-contrasty image after the conversion process.

Local Operators uses the pixels location in the image when analyzing the appropriate scaling for it. This allows each pixel of a given intensity will be mapped to a different value depending on whether it's found in a dark or light area. Local tone mapping requires the system to look up surrounding values for every pixel mapped. This makes it slower (and more memory/system intensive), but leaves you with a much richer and eye pleasing image when correctly done.

Does shooting in RAW matter?

Short answer - YES! While you can still get amazing images from JPGs, tone mapping using RAW files provides much much much more information for the HDR program to work with. While it may take longer to process, you'll be left with a much more accurate image when working with RAW.

When using Aurora HDR to merge your brackets, you're given one of the most human-realistic representations of the scene possible, and when using raw files, you have a TON of information and tools within your 32-bit image to generate a finished photo with the exact look and feel that you desire!

The reality is, you don't need multiple exposures to tone map your image. You can have a single frame and create just as epic and breathtaking details, however, you will have less dynamic range to play with so remember that.

This is why Tone Mapping and HDR are not the same thing! To create an HDR image, you need at least 2 bracketed images. It boils down to availability and style. It's up to you to create an image that's either realistic, or fantasy like.

Go Pro: Studio Beauty Video Training

It's here it's here it's finally here! My good friend and amazing Photographer & Retoucher has released her latest pro tutorial - Studio Beauty Video Training and it's nothing short of amazing! 

Julia Kuzmenko is one of America's best beauty photographers and retouchers. Her work has been seen millions of times, she's been featured in websites and international printed magazines countless times. While most will believe her work is as phenomenal as it is due to her retouching, (which _IS_ amazing), the fact is, she's an absolutely brilliant photographer and master of light! Thus, the announcement of this video tutorial!

The video has 3 segments, (about an hour each), and an ebook, (Read that first!), thats jam packed with information covering everything from beginner subjects like lens selection and strobes to Intermediate and Advanced topics covering workflow and technique! 

The thing i like about this tutorial is its focused on the artistic and technical aspects of the photoshoot on set, helping you get everything as right as possible in camera. This will make you AND your client happy beyond belief, and save your retoucher a lot of headaches!  So be advised, this video will NOT cover retouching/post production efforts. 

As Julia says "Our goal is to teach you to confidently set up beautiful studio lighting and produce amazing images, as well as to lead your creative team and manage the creative process from inception to completion including selecting the right talent, working with models, make up artists and stylists for both commercial assignments and personal projects."

Check it out now for the sale price of $169!!

CHAPTER I: INTRO & PREPARATION      

  • About the Authors & This Training    
  • Your Career & Ultimate Artistic Goals

Your Knowledge & Vision

  • The Basics Every Photographer Must Know
  • Developing Your Vision, Taste and Aesthetics
  • How to “Read” Lighting

Cameras, Lenses & Lighting equipment

  • Choosing the Right Cameras & Lenses For Your Work
  • Choosing the Right For Specific Projects
  • Camera Sensors: Full Frame & Crop Factor
  • Crop Factor & Focal Length Multiplier
  • Studio & Backdrop Choice
  • Lighting Equipment
  • Common Monolight Controls & Triggers
  • Light Modifiers
  • Accessories

Preparation is King

  • Idea, Concept of a Shoot & Choosing the “Right” Team
  • Helpful Documents For Your Work

CHAPTER II: FLAWLESS EXECUTION    

  • Shooting Tethered
  • Standard Camera Settings
  • Common Mistakes to Avoid While Shooting
  • Day-of Briefing & Backup
  • Working With Your Model

CHAPTER III: LIGHTING SETUPS      

  • Establishing Our Starting Point: Why & How
  • Classic Portrait Setup: Various Types of Lights, Light Modifiers, etc.
  • Celebrity Portrait: And More Ways to Fill in the Shadows 
  • Movie Style Setup: Cinematic Lighting: Adding Drama; Working with Smoke 
  • Hazy Colors Setup: Colorful Theme; Working with Color Gels and Smoke
  • Jewelry Ad Setup: Another Colorful Setup; More on Working With Color Gels 
  • Clean Beauty: Other Ways of Creating Rim and Fill Light; White Background
  • Full-Body: A Few Notes on Proper Full-Body Lighting 
  • Doubled Colored Shadows: Even More Ways to Use Color Gels 
  • Creative Mixed Lighting:
    • Mixed Lighting: Fundamentals
    • Mixed Lighting: Reflective Fabrics
    • Mixed Lighting for Beauty

YOUR ASSIGNMENT LIST

Practice not until you can get it right, but until you can’t get it wrong.

BONUS MATERIALS

  • Call Sheet / Template
  • Estimate for a commercial project / Template
  • Model Release / Template
  • Agency Test Package Request / Sample Letter to a Modeling Agency
  • Client Project Questionnaire / Template

http://bit.ly/1Ur384P

A 15-second overview that comes with the Go Pro: Studio Beauty video training.