Category Archives: Computing

Creating the Llyn Idwal photo


This picture of Llyn Idwal in Snowdonia seems to have generated a lot of interest on my Facebook page. And sparked some debate about personal taste. But among the comments, I was asked what my workflow and settings were for this image. So here we go…


Firstly, I always shoot RAW.

Secondly, with the exception of shooting concerts (when I shoot Manual) or helicoptors (when I shoot Shutter-priority with a shutter speed of around 1/60th), I almost always shoot in Aperture-priority mode, with -0.33 exposure compensation.

The first thing I do (these days*) when confronted with a high contrast scene is take a quick shot at default aperture priority settings to see what the dynamic range really is.


Looking at the histogram, showed that the dark parts of the image were just about OK, but that the bright parts were totally overexposed (clipped).

So I took one shot exposed for the landscape and another with 1 stop less exposure compensation, for the sky.

Processing with Adobe Bridge

Some people are fans of Lightroom, others of Adobe Camera RAW (ACR) in Bridge. The process is pretty much the same in either.

My default settings always apply “Enable Lens Profile Corrections” and “Remove Chromatic Aberration”.

First I opened the lighter of the 2 images.

Image1 Basic

I increased the Clarity slider to bring out the details and texture in the grass. But using the Clarity slider will alter the brightness of the image, so I then compensated for this by reducing Exposure slightly, and increasing Shadows (which brings back some light into the darkest areas).

Image1 Curves

I then fine tuned this ever so slightly on the Curves tab.

Image1 Luminance Image1 Saturation

Most of the work went into the Saturation and Luminance changes on the HSL tab. Lightening the orange, yellow and green of the grass/straw, whilst darkening the blues in the water. A side-effect of lightening a colour is it gets desaturated slightly (and vice versa), so I compensated for this by boosting the saturation of the yellows and greens.

That was it, so I clicked Done. This saves the changes without opening Photoshop.


Next I opened the darker of the 2 images.

Image2 Basic

The exposure was already perfect on this for the sky, so I only increased the Clarity slider to bring out the detail in the clouds.

Image2 Curves

On the Curves tab, I darkened the shadows area of the image to add more drama, whilst adding a control point in the highlights to avoid changing them.

And that was it, so I clicked Done for this image too.



With ACR in Bridge being as powerful as it is, I very rarely need to use Photoshop these days. The only things I normally use it for are:

  1. Adding a watermark/signature
  2. Merging images to form a panorama
  3. Removing large/complex objects from the image

I now needed to merge these two images. So I selected them both in Bridge, then chose Tools->Photoshop->Photomerge…

This opens a dialog where you can choose how to merge the images.

Photomerge dialog

This feature is brilliant for aligning images, even when handheld. But as I wanted to control which parts of each image I used, I deselected the option “Blend Images Together”

PS layers  PS layers cropped

This brings both images into a Photoshop document on separate layers. After cropping I then selected the parts of the brighter image that I wanted to replace.

PS sky selected

I used the Quick Select tool to select the bright sky (and held down the Alt key to remove parts of the selection when it accidentally selected the snow). I zoomed in and reduced the size of the tool for extra precision when required.

I then chose Select->Inverse, so that everything EXCEPT the sky was selected, clicked Refine Edge and feathered the selection very slightly.

PS layers Add layer mask

And then clicked the Add Layer Mask button. This automatically adds a mask to only keep what was selected. Using a small, feathered brush, I manually tidied up the mask slightly.

PS layers Add Curves Adj

To add even more drama to the sky I added a Curves Adjustment Layer.

PS Curves properties

In this I increased the contrast even more.

I increased the amount of blue in the shadows, but reduced it from the highlights, and ever so slightly reduced the amount of red in the shadows.

And that was it!

Scaled down for Facebook, added a watermark and save for web.


* Back in the days of film, I would use my wonderful Pentax Spotmeter V to take readings of different parts of the scene.

Blackmagic Hyperdeck Shuttle


When Blackmagic originally brought out the Shuttle, it seemed like a great product if you wanted high quality uncompressed video. But that came with the downside of massive disk space requirements.

Version 2 was then released which allowed recording in either ProRes or Avid compressed formats. Brilliant. And a great price.

Now it accepts SSDs formatted in ex-FAT format too, so no need for nasty Mac-emulations on the PC.

So I finally bought one, to record 1080p output from my Red Epic and Sony Z1 cameras.

Connecting it to the computer

It comes with a DVD with software and manuals for every Blackmagic product! I read the Hyperdeck Shuttle manual and installed the software.

The Shuttle has a mini-USB socket to connect it to a computer. I did this and then ran the Hyperdeck software.

This is where I had my first major problem:


The software did not recognise that the Shuttle was connected. Eventually I realised that one of the grey buttons was actually an On/Off button! Turning it on helps. LOL.

I could then set the recording format to “Avid DNxHD QuickTime”.

Connecting it to a camera

The built-in battery only lasts for about an hour. Not much use if you are recording 2 hour concerts as I frequently do. So the first thing I needed to get was a cable to connect the Shuttle to one of my V-lock batteries. I spent ages reading through the Blackmagic website and on forums with no definitive advice. Then eventually I was given a link to the perfect cable on eBay. And only about £12. (Note: it does come with a mains adapter, but I prefer to move about on battery power when I can).

The next cable needed was an SDI to Blackmagic mini-SDI. Well I already had a Red mini-SDI to SDI cable, so I thought I would be OK. But no, both the output of the Epic and the input for the cable are male plugs. So I’ll need another cable. I’ll update this page when I find the right one.

In the meantime I will use the HDMI connections on both devices. I have loads of HDMI cables!

The next problem is that the indicator LED for the video signal did not light up. But there was definitely a video signal coming through the cable (I tested by plugging into the TV).

After a lengthy phone conversation with Blackmagic support, we established that the LED lights up when you have a 720p signal at any frame rate. But that it only lights up for 1080p if the refresh rate is 25Hz (irrespective of the frame rate). This is just wierd as the UK and Europe run on 50Hz. I shall investigate further with other users.