The Sunset in HDR :: three ways

There was a half decent sunset tonight, and a perfect opportunity to test out a 5 bracket exposure and three different approaches to post processing the higher dynamic (and 32 bit colour) image in the new AuroraHDR 2019.

Firstly I really confirmed that the default tone mapping is pretty good (almost good enough by itself). However it was then easy with the adjustable Gradient filters to add a little vibrance and warmth to the top of the photo. Giving a result perhaps a bit closer to what I experienced. Then I tried a couple of presets (now called “looks” in Aurora HDR) and settled on Warm Landscape as the best match albeit perhaps a little too colourful. This is powerful stuff and a joy to use.

Day One ... cont. jpeg .vs. .orf RAW

This was not a surprise. My lightroom (still ver 4.4) could not read the Olympus RAW format .orf. The same thing happens to most owners of new cameras, they have to wait for an update from adobe and they complain a lot on the internet. Please don’t think I’m just complaining, I understand the issue but I not interested in the adobe subscription so this probably marks the beginning of the end for lightroom in my photographic tool set.

On the left is the jpeg image straight out of the camera, shot in Auto. On the right is the same image but the .orf version read by Aurora HDR 2018, which can read the Olympus .orf RAW format. To keep with the spirit of using Auto I have only used it’s basic Tone Mapping (just stretching the tonal range) as a fairly basic thing you might do with any RAW file. I like both but the one of the right feels more like being there, so I made it my PhotoFriday post this week.

Notan Versus Zone System

Edsel Adam’s Zone System is a lot like a multi-tonal notan system, It has 11 steps  that correspond to how he could capture light to dark on a negative. Ansel choose to use just 11 there were some variant before his that use 7 or 12, because that gave him a 5 stop range, which he was confident a black and white film negative could capture at the time. Each zone covering half a stop. One F-stop corresponds with a doubling of the quantity of light (luminosity). Using and odd number does mean the average grey tone is centered in the scale. This is magic tonal your camera is trying to average the exposure of the image. Thus this will be one of the intervals rather than fall between them. There are lots of Zone System Charts on the web (like the one below). However few are design as field references, and further most discussion of the Zone system on the web related to post processing.

 

Ansel numbers his zones starting at the Darkest Black, whereas I see many US based artists tend to start there numbering from the White. The numbers don’t matter really it is understanding where the tones lie in the image. More importantly where they might sit compared with an average exposure, and where you might want them in your final photo. I have put together another little field Chart/Guide this time with the 11 tonal steps. It is more useful as a guide on how you might arrange the tonal mapping for your final photo/print than an aid to composition.

When I was putting together these notan guides I was using the RGB scale to select by neutral grays. Any colour with the same value for R (red) G (Green) and B (Blue) becomes a neutral grey colour. Since White R,G,B is 0,0,0 and Black R,G,B is 255,255,255 I had assumed that the grey midtone would be half way between ie R,G,B 128,128,128 but it just appeared a fraction or two dark to me (and warmer). I have since discovered that both Adobe RGB (& sRGB supposedly) use a gamma encoding to adjusted scaling that is a type of power curve so the steps not linear. The table below gives the RGB values of the 11 tonal zones above. This difference is subtle but could affect and Tonal check cards you would like to make yourself.

Zone	O	I	II	III	IV	V	VI	VII	VIII	IX	X
RGB	0	33	51	72	94	118	143	169	197	225	255

My thoughts on collecting Photo Reference for Painting

Whilst there is a school of artists that still insist the only landscapes are those painted plein-air. The vast majority will finish their big painting in the comfort of their studio, a few from just sketches but the majority will use photo reference. I love to sketch and paint outdoors but time and the light seldom let you finish a big work outside. However I know that when you try to slavishly copy all the detail in a photo it can make a painting look very flat. Whereas a sketch hurriedly dashed off is more likely to be dynamic and truly capture the sense of the place. So my take on this is to spend time to do a sketch or small composition painting to capture your impressions of the view, and record the important aspect you see. Do this on site. I like to use a watercolour wash, then add the the detail with a soft pencil afterwards (I’m not filling in a detailed sketch with colour, I’m putting down the area of colour and main composition elements then adding a bit of detail.) Or alternatively I just sketch monochrome in pencil of graphite stick.

So My First Rule of taking reference photos is

Start with a sketch

• Put your camera down
• Do some compositional sketch to capture you what you first see and feel. Just the main elements

Whilst I wait for the watercolour wash to dry enough to sketch without damaging the paper. I find this is a good time to pick up the camera and take those reference picture because you now know what is important in the image. The first photo being the obvious, the same view you are painting. This is where a camera with a zoom lens comes in handy because it is likely that your composition will not match a snapshot from your camera. You will probably have to zoom in or out. In my example I have taken two images side by side and then stitched them together, using Austostitch, because my sketch is a little wider than by camera can handle (alternatively I could walk back behind me before I took the scene, assuming their is room and the full scene if not obscured)

However don’t stop there, take at least an additional 4 views, zoomed in (or walking close) to key aspects of detail that will help you finish or zoom out to get the broad feel of the place (you might like to add some slightly out of view detail or subject into your composition). If there are large areas of colour or texture photograph them, they could be the key to visual appeal in your photo.

 

So My Second Rule of taking reference photos is

Take Five

• The composition you intention to paint.
• Plus 4 details zoomed in or out, or concentrating of a key texture or colour

The biggest limitation of trying to copy a photo religiously happens with tonal issues. Whilst modern digital cameras are great they still have limitations with Dynamic Range and photos typically look flat compared with what you saw as you where sketching. There are two approached here that can help here by they may require a upgraded camera.

The first approach if to take a bracket set of images (many but not all point and shoot cameras can take a set of three EV settings, older camera usually don’t have this built in but there are several camera apps that add this capability. The bracketed set gives you an underexposed version (to focus on the highlight) a normal exposure and an over exposed version (which will give you a lot more details in the shadows). These three images should give you the ability to play with the tonality to suit your composition. If you want to take the tonal representation further you could investigate processing this bracketed set as a HDR image and refine the tonal mapping to bring out the tones as you remember. HDR is an advance post processing technique that requires specialist software but it will give you a lot of freedom adjusting the tonal range.

The second approach is to take RAW format images (probably as well as jpeg). This require software that can handle RAW images (like Lightroom, Aftershop Pro, OnOne or RAW therapy). The advantage here is the raw format records everything recorded by the camera sensor and it is possible to “pull” extra detail out of the shadows and often bring back the highlights. This requires learning how to use this software and extra time to refine the RAW images. However the ability to refine tonality and colour can be wonderfully inspiring. I started to like having the overhanging tree as part of the composition.

So My Third Rule of photo reference, if you have the technology to do it, is

Why not Take Ten?

• Use Bracketing
• Take and Process RAW images

PhotoEditTool :: Another good pair of add-ins

Following up on some more add-ins for Aftershot, I reloaded the 64-bit version of Bez, a neat tool for managing tonality and this new version is smooth and fast. Bez (which comes from its use of Bezier Curves) was originial develop for Bible to bring in Lightroom like tonal controls. I like the 5 tone narrow curves that mimic the basic brightness controls in recent versions of lightroom. You get separate sliders for Shadows(Blacks), Low Midtones(Dark Grays), Grey (aka Mid Gray), High Midtones (Light Grays) & Highlights (Whites). It also incorporated an opacity slider, useful to reduced the effect of the filter itself. It definitely enhances Aftershot tonal controls.

The other add-in of interest when considering tonality is Zone. It is a new, well I haven’t noticed it before, and it simply lets you see the Zones (from dark to light) as used by Ansel Adams in his Zone System. When you active the Preview Zone Systems by tick the radio button, the photo you are working on becomes black & white and the hightlight a zone slider is activated. Sliding the the zone changes from 0 (the darkest) up to 10 (the lightest). Each zone is highlighted in a dull yellow as you step through the zones.

The magic happens if you see that one zone overpowers the image (in this case the shadows are very dark and lack detail and represent a large portion of the image) so you can then adjust the appropriate bez sliders. I prefer the 5 tone sliders at the base of the Bez panel. Remember each of the 5 tone sliders crosses two zones in the zone system.

It is also very important to turn zone off, once you are happy with the tonal balance, So that the final photo is correctly rendered (in colour).

There is no HDR technique here, although I am capturing a AdobeRGB colour image (thus high bit colour). All I have done is looked at the 10 zones of Ansel Adams system and made sure I have balanced the tones in each zone. It this case it has bought detail into the shadows and midtones, at the same time this lifts the apparent intensity of the green foliage.

MDR rather than true HDR

I’m using the abbreviation MDR to mean Maximum Dynamic Range, to differentiate these approaches from “true” HDR.

Something I haven’t tried out in a while is Amalence’s HDRAW standalone utility. This utilizes Tone Mapping technique, allowing it to preserve the details while fitting the highest dynamic range image, taken from a single RAW photo, into the limited dynamic range of a single JPEG or any other 8-bit format.

It displays the options in popular filter examples that you just need to click on the most pleasing option (ie not shinny painting please)

Another way  I have seen described to get a HDR set from a single image is to take a well exposed image and create an overexposed version and save that and then an underexposed version. Normally by moving the exposure slider by the equivalent of one f-stop. This might let you use tone mapping tools but it does not get you extra tonal range, you can find in bracketed exposures. If you want to follow this approach the new AfterShot HDR has this as its second option to create a HDR file (I don't recommend this approach)

The final approach, which I feel is the most obvious, is to use software like lightroom to stretch the tonal rendering to its maximum (well maximum acceptable amount). In this example I am using lightroom’s development module I just use the basic tonal controls controls at the top of the development tool panel. I fist try the whote balance, although in this case I feeel the as shot does reflect the warmth of the first dawn light colours well. Next I have a adjusted the exposure up a little (moving the whole histogram a littel to the right because it is so heavily biased to the left, the dark side). Next I adjust the shadows and blacks to keep the forground dark (and hide the shadow detail, for pictorial reasons). Finally I lift the highlights and the whites (there aren’t many as shown by the histogram). I lift the clarity (local contrast) and vibrance (the intensity of the deeper co0lours just a little.  I do have a preset I developed ages ago called SDR+ which follows these steps but I actually prefer to do the steps manually because I can finesse the sliders in each step.

A number of software programs offers histogram stretching tools and they can produce HDR like results but they are less easily controlled than the tonal tools in packages like lightoom and AfterShot.

Cameraphone :: One Phone 3 Cameras

   

I have a new phone an LG Android and the review’s seem to can it as very ordinary but to me it is s reasonably decent camera to have always in my pocket. Specifically to get simple snaps and collect reference material for my sketching.

One thing that many people don’t realise you are not locked into the supplied camera app that came with your phone. There are dozen of good camera enhancements out there.

Pudding Camera gets some favourable reviews and has a simple and easy to use controls, the special feature is you can choose the style of camera you wish to use (the above left photo) is Basic Camera with a vintage look.. I’m still experiment with this one but being able to see the final effect before you take a photo is great.

HDR Camera+ was a favourite back on my HTC wildfire, it takes three exposures and then creates a HDR image, all processed on the phone and it has a range of tone mapping in the form of little filter style icons. I still like it (centre image above)

A Better Camera, is another camera app from Almalence who create HDR camera+, for a small cost you can get am impressive array of extra controls for your camera, akin to the controls available on most Bigger DSLR Cameras. They are on a pull down icon menu but easy to learn and navigate. For me its bihggest benefit is that it does produce clearer and more vivid images (see the image on the right above), with the DRO (Dynamic Range Optimization) option set. This is a propriety technique similar to tone mapping that seeks to make the camera see like the human eye!

Rethinking the Sketch Approach for a Photographer

I haven’t actually used my camera this week (a very unusual situation) but I have been thinking about the different way an artist might approach an image via a sketch and a photographer that just needs to press the shutter. They are quiet different approaches yet they are both about being able to “see” the final work.

This is a photo of my small sketchbook and sketching gear. I have drawn a quick watercolour sketch of my own eye. It is in fact the small A7 sketchbook that I carry in my camera bag, taken last weekend as I was waiting for the sketch to dry. It is a nice example to explain the difference in an artist’s approach to seeing via line, tone and colour. It is also a nice bit of artistic self reference as I have long used such an image as my blogger and more recently google+ profile photo. I am also going to use Paint.NET, which is still free to download, (donations are appreciated) and a wonderfully simple yet powerful and intuitive photo editor for this demonstration. See also my post on the anatomy of Paint.NET Workspace

1. Line

It is very common for an artist to begin with lines. Our eye love lines and edges, they quickly follow these subconsciously. Eye tracking is a relatively new high tech applied science with lots of applications, and it demonstrates that our eyes tend to follow lines almost involuntarily. Artist have traditionally realised this intuitively and they selectively lay down the lines they need to build their image, so as to capture the viewers gaze. Often these lines are edges, something that is the boundary between light and dark or just a thin change of contrast. Whilst an artist will probably use a pen or pencil a photographer can easily find the strongest lines by converting their image to just black or white. Some software give this as a separate tools with a threshold slider that changes the point an image changes from black to white. Another common way to achieve this is using the “curves” (tone curves). These are a very mathematical looking tool but they just allow you to remaps given luminosity (light intensity or tone) and often colours with considerable precision. In this example, using Paint.NET the horizon axis represents the input intensity and the vertical axis represent how this intensity is to be output. The upper right is the lightest tones (the whites) and the lower left is the darks (the blacks) So if I grabbed just the luminosity curve and move that point up to the top of the graph suddenly and tones this shade and lighter become white. If I then grab a nearby point just to the left and take it down to the base of the graph, suddenly all these tones and darker become black. If I moved these points horizontally the threshold of the black to white change moves through the tones. I’ve chosen a threshold that avoids focussing on the eye sketch itself. What is created is a black and white silhouette that highlights all those strong lines that out eyes like to follow. This is very useful in understanding our eye flow and establishing points of interest. An artist “trick” is look at their sketch upside down (in this case I’ve simply done a flip vertically) as this tends to let them see the shapes in a more abstract way rather and interpret the objects they represent.

The pink lines show the likely flow of the eye. Those that bringing the eye into a center of interest, such as my eye sketch in this case, will be keys to help the artist build his composition.  A photographer should also study these lines and help in the composition because they might need to be enhanced during post processing. Unfortunately strong lines at the boundary (the red dotted arrows) will tend to draw the eye out to the edge and possible away from the image. An artist would probably not even drawn these, however it will be important for a photographer to see these and perhaps dampen them in the post processing, by using a vignette or central focus that blurs the edges, or even a gradation mask and Gaussian blur.

It is probably unnecessary to keep this liner version of your image, so just Undo these “enhancement” with a couple of  <Ctrl> <Z> or clicks on the big blue back arrow icon on the menu bar.

2. Tone

Most artist know that half squinting their eyes tends to desaturate the image and allows them to better judge the tone of the subject. Tone is “king” in realistic painting/sketching and it is important to understand how that tone maps onto lines and shade on the page. Where are the darkest darks and lightest lights? There are lots of ways to convert a colour image to black and white, edit tools, presets, filters and plugins. However for the tonal sketch aspect the simplest and best way is just to remove the saturation by moving that slider to the right. in this example I have moved the slider all the way to the right.

Half closing the eyes has a slight disadvantage in that it also lowers the light entering your eyes and thus darkens the image a little. There is no need to replicate this.

This black and white (actually its a greyscale) image should really help you understand the distribution of tone. Where the darkest tones are, where the lightest tones are and how these tonal areas connect. Often it is the areas of greatest contrast that interest our eyes and make for natural centers of interest. I find this greyscale images is also very helpful in guiding composition, ie the best way to crop the image. Notice I’m not trying to follow the rule of thirds I’m just trying to balance line, form & tone.

Once again it is time to hit <Ctrl><Z> and undo any changes and get back to the original image.

3. Colour

Another trick some artist know about is “defocusing” your gaze. This is a bit of a challenge if you haven’t done it before. The idea is to deliberately make yourself cross eyed and your eyes will no longer be well focused. What you hopefully see is really the dominant areas of colour. To train yourself to do it hold up your finger, or better still your pencil, focus on just its tip and bring it closer to your nose. With a little practise you should be able to remove the pencil and take in the whole defocussed view. Of course this is much easy to do with your camera (for example on a DLSR you just grab the focus ring and crank the lens out of focus while looking through the viewfinder). You will be surprised how much of the detail is gone from the image but you will still be able to make out the dominant colours.

The green to blue (harmony), then to blue against strong ochre (yellow) contrast works well, but the red of the rubber band distracts from this. A photographer might reach in and remove the rubber band (if the defocussing was done in the camera before the photo was taken). Alternatively this could be masked and selectively desaturated in post processing.

Time for <Ctrl> <Z> again, to Undo. You may or may not have saved these versions but you should have seen a few extra things in your photo that will probably help you enhance the photo during post processing, much like an artist referring back to his sketch book.

PhotoProject ::Photographing a Sunset as an Artist might Paint

I saw an interesting article is a recent copy of Australian Artist, it was the forth instalment of a 4 part workshop challenge series on Mastering Sunsets by Richard Roberston. He correctly identifies that a brightly coloured sky and deep shadows in the foreground is a very difficult subject to photograph correctly. and offers a simple way to expose the setting sun & sky correctly (point the camera towards the sun and half press the shutter and hold it, then move to get the composed image you want and then fully press the button releasing the shutter). Next take a second exposure for the shadows (by pointing at them and again half pressing the shutter and returning to the composition you want before pressing the shutter fully) The article them moves on to describe “how to paint better than a camera” and it focuses on “seeing” (and analysing) colour and tone However the sunset is a fleeting event and even an great artist will have to work fast to record even a small sketch, but that sketch and time spent looking for and understanding the the true difference between what a camera sees and what the human eye sees, will give the artist the ability to lift a studio painting to the next level even when they are using a photo or photos as extra reference.

I actually think the same logic can be applied by a photographer but the photographer may be at a disadvantage if he is not familiar with looking for the chromatic value and tonality in colour, (with his eye rather than just his camera). Further few photographers carry around a sketch book (other than me) so they need to do a few observations and commit them to memory.

Tonal (an artist will squint, but you can just look through the viewfinder and set your camera slightly out of focus)

• Look for the big areas of similar tone?
• What are the natural positive and negative shapes? (maybe you need to find a interesting negative shape in the foreground to balance the composition)
• Where is the lightest, brightest part?
• Where are the shadows and how dark do they appear?

Dominant colours (again looking at the de-focused image in your viewfinder can help)

• What are the 5 dominant colours? (don’t just say yellow or orange for a sunset, there will be more)
• Given the colours a name? (use your own favourite/pet names, you’ll remember them better)
• Give the a colours a shade? (its tonal strength, pale, bright, desaturated, dark )
• Is the colour scheme Harmonious, Complimentary, Analogous? (an artist might drop a colour that conflicts with the overall scheme, you’ll have to do this in post)

If you have a camera that takes RAW image format and you have software to post process it, take you photo in this format because you may be able to tease out some of these memories. Remember an unprocessed RAW file can look very flat even compared with the equivalent jpeg. It will have to be post processed for sure!

This is a place from which I have sketched and photographed many sunsets, and over last weekend there where a couple decent ones. It is a nice place because the lacy texture of the banksia forms an interesting silhouette and strong foreground.

JPEG Out of Camera
RAW Unprocessed in Lightroom
Tonal & Colour Adjustment in Lightroom
After Shot Pro Perfectly Clear
Perfect Photo Suite Magic Landscape preset

Whilst the difference may not be dramatic if you start with reasonable exposures. I am including these comparisons so yu can see it is possible to tweak the information in a RAW file to give you a richer image, perhaps more like you remember when you witnessed the sunset (You did commit to memory the tonality and colours you saw, didn’t you!)

The other alternative, and it is a good one, is to take a bracketed set of exposures. The logic here is even if your camera’s lightmeter makes a wrong selection, for the best average exposure you should get at least one ok image. If you have access to HDR software then this set of different exposures can be combined to give a fuller dynamic range. If you have a google+ photo account and use autobackup, google may create an autoawsome HDR* for you when it recognizes a suitable bracket set of jpeg images. Unfortunately these can sometimes be a little lurid and over saturated.

HDR Picturenaut with Lightroom
HDR Google+ AutoAwesome

As the sun sinks slowly in the west

... or so we remember?