What I am looking for from HDR

Its a very overcast day after yesterday’s strong wind but with that calm before a storm feel. Not an exciting time to take a few photographs (yet). What I did notice was a new yellow rose had a few buds about to flower but had been very dried by the winds so I gave them a light spray of water and took a couple of bracketed photos of the new buds.

The close up simple composition gives me a great opportunity to compare three of the HDR programs I have used recently, and specifically to discuss what I like to use the HDR Technique to do. I have written a fair bit about HDR. However few people realize how often I use it. I think that is because I am just trying to create an image as I remember the scene, rather that what the camera recorded. The images above are all a bit dark, but that usually doesn't matter within the HDR process. If I was to process just one image I would choose the one on the right and lighten it a little and increase the contrast. Since I have a RAW file that would be simple.

 

However here are alternative ways to process these photos

Picturenaut

This was my go to program for a long while because it was easy to use, free and could process RAW files (which I reasoned gave the HDR process more dynamic range to work with). Importantly for someone that usually hand holds while taking the bracketed set, it has a decent alignment correction. The ghosting (removing ghost from people or things that moved between exposures) work for small movement but my experience was it could misbehave so I only used it when I saw obvious ghosting without it. I also found that it would often need the EV setting of the images updates (ie they would often just all read EV=0). In the table beside each file used.

 
The HDR image (which can be saved) is very dark like my original photos but when I select Tone Mapping I generally select adaptive logarithmic method and accept the default settings and save it was a .tiff file. Preferring to then finish the result in either Lightroom or OnOne.

 

AfterShot HDR

When the HDR was added to aftershot in version 2 I became an immediate convert. It is also handles alignment (mostly ok). It also handled RAW files (unfortunately version 3 of aftershot Pro does not pass raw files nicely into the HDR merge program, so I must maintain a Version 2 copy just to do HDR) and it is vary easy to set up you just select the files you wish to use and then right click and select to Edit With AfterShot HDR\Exposure Merge

 
The ghosting has to be fixed by masking away the ghosts you don’t want (on specific images) which can be a little tedious but can be much better controlled than the automatic methods. Again the aligned image looks very dark. However when you process the three images into one the image generally looks much better exposed (its not magic the dynamic range is being stretched to fit the image)

 

I have the presets turned off and generally only make some minor tonal adjustments. My preference is to add a little contrast and deepen the midtones and/or shadows. In AfterShot there is an extra step where there are as a number of basic edits to finish the image but again I prefer to save the resulting photo as a .tiff file and then do my finish in Lightroom or OnOne.

Nik Efex HDR Pro

Whilst I’ve had Nik software since google offered it for free download. I was a little slow to try out the HDR merge features. I have been working through the various screen via the rather big collection of presets. To my taste a lot of these are just hideous, those strong halos around constraty edges and super crunchy detail and lurid colours are off putting. Still I like enhanced colours and a little extra contrast so I can see a few presets that are getting me close to the nature feel I am looking for. These include default, balanced, Soft Colour and soft Landscape presets. Nik Efex HDR needs to be run from Lightroom and it has to be started a little differently to other plug-ins. Instead of the normal Edit In option, you have to export the photos to Efxex HDR  Pro via a specific option in the export menu (shown on the right). Lightroom does take a little time to prepare these exports.

 

I am still experimenting with how to do minimal tonal adjustments, but already have discovered that I need to slow down the drama (mostly) and often experiment with structure which is a bit like lightroom clarity and OnOne’s dynamic contrast. Again I prefer to save the .tIff image at this stage and do the tonal finish in lightroom. Perhaps with a little more practices I’ll gain more confidence. For the moment Nik’s Efex HDR pro remains an interesting diversion rather than a go to tool.

In the end I choose the Aftershot Pro .tiff image as having the closest to my feelings looking at the water droplets on the new buds. I finished this in OnOne 10 using the perfect eraser to get rid of the hole in the petal and a small curl of another bud below left, crop in a bit and add my favourite big softy vignette to bring the rose forward from the background a little more.

All of these steps take considerably longer than just processing a single image but I tend to think the extra time spent is worthwhile and creates a stronger and more real image.

PhotoProject :: Making My Own Layers

I photograph this scene (which is at the end on my street) many times throughout the year. Whilst it wasn’t a spectacular sunset, and I’m looking south in any case, the sky is nicely dramatic and I felt it woild suit to the HDR treatment. I’ve even tried the HDR three ways, Google’s auto awesome HDR*, Aftershot Pro’s new HDR & Picturenaut. They are all ok,  somewhat blurry, some with noticeable halos and/or don’t quite capture the time & place.

  

Which is all well and good but I would rather be experimenting with what is inspiring me at the moment. I am currently fascinated with what make Fred Williams’s work so appealing. Part of this related to scale, and it is pretty impossible to convey that here on a small screen. The next two parts are more easily tackled here. I find Fred’s work really captures the colour and texture or real places in the real world. The essence of the place’s Australian-ness. Many of Fred’s works don’t have a clear horizon, they are more likely to appear abstract up close, Just squiggly ornamentation on a strongly coloured ground.

My initial idea to find the colour ground, was pretty simply just create a background layer which is simply the image blurred. There are Gaussian blurs in most photo editors but in this case I am experimenting with picasa’s soft focus filter which is like a vignette only instead of darkening the edges it puts thing progressively out of focus.

The surface calligraphy or “ornamentation” was more about how Fred made his marks. I like to think of it as he was painting or writing in a special font, one that matches the texture of the scene and more than that tells the story of the place. Even more important was that there is often and economy in what Fred has written, a good precise without having to tell the whole story. So I was looking for a way to filter the photo to find those few lines, some key things that identify the place, without having to record all the detail. I first experimented with the pencil sketch filter in picasa but it was pretty lame (see image above) so I took this through the infra red film filter and then back via inverse colour filter (image on the right). Now I’m getting both simpler and still keeping the feel of the road and trees, without a detail overkill. The final step for now, also carried out in picasa, was to create a multi-exposure collage, which simply overlays the two images. The result was a greyed out mess so I undid the inverse colour and overlayed again. This time the detail is light and the coloured ground is still toned down but still brings a strong sense of the time of day

This image looks nothing like a Fred Williams painting and not a lot like a photo of the scene. Yet it pleases me. I am staring to understand what is important. I feel I’m on my way for an interesting journey.

ThePatch :: Landscape/Sunrise

This was one theme I was really looking forward to, I like the striking lighting of sunsets and sunrise but have learned whilst they make wonderful images they don’t sell as prints, I suspect everyone thinks they can do better themselves with their iPhone or compact digital camera. So I hadn’t been putting as much effort (perhaps subconsciously) into being there at the right time and in the right place recently. However I had figured getting nice reflections off the nearby lake in Jells Park would be perfect. Well nature let me down! I had a week of very ordinary overcast lighting and so little colour. Its not as if I got bored or discourage. There was actually plenty of things going on to photograph. Which reinforced the 50/50 time limit rule, at least that’s what Matt Kloskowski called it in a recently. The idea is to take your intended shot(s) and then take a many again trying something different and perhaps more creatively. You will return home happier trust me! Here are just a few of the things I saw & photographed

Returning to the theme at hand. I only got one morning with much colour and I was not in the spot I planned, but I did find a couple of interesting compositions and thankfully took a couple of bracketed sets. The autoawesome HDR* created by Google+ was very good by their normal performance BUT it was teetering on the surreal, not what I wanted. Oo I redid my own HDR this time using Picturenaut to just merge the images and give me a 16bit file which I further manipulated in Lightroom with some additional tonal and colour tweaks in Perfect Effects 8 ( A sobering thought is I probably wouldn’t have gone that route if I hadn’t seen the google+ HDR*, see the first two images below).

PS please excuse the lateness of this post I was actually hoping for a good sunrise this morning.

Bracketing, HDR & ToneMapping via RAW

hilst much of the web based advice on HDR focussed on using a bracketed set of jpeg file, you can and perhaps should, consider working with the RAW files. With a fair bit of conscious effort. I did avoid using detailed technical terms in my previous discussion of HDR, but in the context of why begin with RAW files is better, I will need to get technical. RAW files start with a larger bit depth (12 or14 bits for each colour) in the colour space than jpeg which only use 8 bits, so you begin potentially with more detail in terms of the intensity reading. Not all HDR can read RAW files but most of the better packages claim to. I have found Picturenaut (which is a community supported effort that came out of Germany to fill the void that HDRShop left when it languished as it became commercial) suits my approach, the raw format i use and other software tools I have (particularly lightroom). It has the advantage of being able to do automatic image alignment, color balancing and ghost removal during import and merge (great features if you don’t always use a tripod). It also does the tone mapping fast.

The first step in any HDR system is to merge the source images and these will get combined into a large and higher dynamic range file (normally this will work on a 16 or 32bit colour space. Like RAW files these are frequently in a propriety format (and large). The software called radiance HDR, with a format designed by Greg Ward (now often referred to as RGBE) which can store all this information and it is becoming somewhat of a standards. Some issues that can affect this merge are poor registration of the images (ie not taken on a tripod) and this is can cause ghost and shadows or just “soft” images. Better programs like picturenaut and photomatrix can do some alignment by feature match, or subjects that move between exposure (ghosting again) or strongly overexposed and/or underexposed source images in the bracketed set. Most packages then display this composited file and it will probably look flat and perhaps a little dark. Don’t worry the best bit is about to take place.

The tone mapping step is where you map all the detail of intensities back into an image that can be reproduced within the dynamic range limits of the intended display or print that hopefully will match what you saw when you took the photos. This is a large and intricate topic and many approaches have been applied. For gene4ral use I like the approach described by Eric Reinhard, which draw heavily of traditional darkroom techniques such as those of Ansel Adams. It is  a logarithmic dynamic range compressor but with a more linear portion of the dark and light ends. There are many variant with names such as Photoreceptor or just Reinhard. Better Tone mapping software lets you adjust the various key settings, and at the same time shows the intensity and/or a preview, letting you refine the tone mapping.

The three panels below  show three other common tone mapping approaches. The Adaptive Logarithmic, also know as Drago, after its developer, is also popular and suits situations where you want to preserve the colour in highlights (such as a sunset), The Bilateral  is an example of an unfortunate choice in tone mapping that falsify the colours in this particular image.

Adaptive Logarithmic	Exposure	Bilateral

To finish my photos for display of the web I have imported the files into lightroom, fixed any excessive clipping in the blacks, then exported the images, at a lower pixel count (made then smaller) sharpened for the screen and set them to sRBG but with no other post processing.

 

This good blog post by Klaus Herrmann which to put in his words creating HDR images the right way, does deal with creating 16 and 32-bit Colour in HDR images. His HDR cookbook is worth a read as well.
(I have found that whilst picturenaut can create both 16 and 32 bit TIFF images, I have been a little disappointed with the 32bit versions which often can’t be read by lightroom or “flatten out” when edited. The images show here is based on 16bit HDR)

Reflecting on the true colour of brass

  
I was contemplating what to enter in this week patch challenge, with the dual theme of Door/Door Knob and renewal, and I realised I had change the door knob on my studio to a lockable type. the contrast of the old worn paint and the bright shiny brass might make a nice simple story and photo. Metal surfaces, particularly when they are strongly reflective can be a challenge to get the right exposure so I had taken a bracketed set and kind of forgotten about it. I had used lightroom to expand the tone a little on the best exposure and shifted the clarity and vibrancy a little to the right but the brass was just a little to warm and the orange blown out. Other things took my attention and by the time I returned to decide whether to upload this, my photos had been auto-backed up and google+ had done its auto awesome thing again. I immediately spotted that the colours where truer (the door was open and the doorknob clearly in my view). So I immediately created a 16bit HDR image using picturenaut, and finished it in lightroom with much the same approach to the single image. The difference is a little astounding but I like it because to has treated the strong colours much more subtly and now looks exactly right in my view.

Colour & HDR

I took this series of photo after spilling a pile of fish oil tables on a place mate and turning them around I noticed the refraction made for very interesting patterns of light and it wasn’t long before I had shaped the pile into the crude outline of a fish (my love of self reference got the better of me here!). I then waited for see what google+’s auto backup and auto awesome might do. Well it was not so exciting in terms of the stop motion (on the left) but the HDR effort (below left) got me think about controlling colour in HDR in general. So I have run a couple of HDR using the picturenaut tools I am familiar with. the results where pretty amazingly different (shown below). Individually they are all fine but the alteration of the colour is as dramatic as the “contrasty “HDR look””. I have always like the idea of stretching the dynamic range of an image, which is what the HDR technique promises, and I have used it to get closer to what I actually remember seeing at the time. The issue that is very clear to me here is stretching the contrast can significantly impact the colour. In any case this is probably one of the examples where HDR has not added to the impact of the photo I actually much prefer the +0.5 EV (slightly over exposed) unaltered JPEG image (above) anyway

Google+ HDR Details of tone mapping approach unknown?	Picturenaut (all defaults)Using Standard Weighting and Photoreceptor tone mapping (aka Reinhard) with 8 bit jpeg output	Picturenaut (my Approach)Using Mid Weighting, Colour Balancing and Adaptive Logarithmic Tone mapping (aka Drago) with 16 bit tiff output and  a few final tonal tweaks in lightroom

Trying to keep HDRi real

Taking the sunset tonight, with the polarizing filter still on the lens, I was conscious that the images on the back of the camera was very dark (underexposed) but the colours of the sunset looked rich, like the actual sunset in the +1 EV image from a bracketed set. So I figured I should do a bit more experiments with HDRi in picturenaut using high bits per channel, which this package can only export as .tiff files, but minimal tone mapping. In this case I used just an effective +1.3 EV exposure adjustment of the whole image.. Again I was not able top read the 32 bit version into lightroom, where as picasa could display it? However the 16 bit per channel files loaded easily into lightroom and responded beautifully to some tweaking of the shadows & black tones and slight clarity and luminosity increases. These adjustments did unfortunately highlight the digital noise, which is typical of low light exposures, but this was easily corrected with the lightroom 4’s development/detail sliders.The combine file is no longer a RAW format but it does hold and extended dynamic range that the basic lightroom development controls can adjust, and I feel this approach does it naturally, not in the lurid surreal formats so often blamed on the HDRi technique itself, but are actually related to some preset concepts of the tone mapping options in common HDR packages. So Instead of “finishing” your HDR work in picturenaut, photomatrix or other HDR software, instead try saving the combined image at a higher bits per channel and do the final tonal adjustments in lightroom (or photoshop)