Infra-Red Timelapse

Having had my Canon 50D converted to IR and knowing that the 50D can deliver Magic Lantern Silent (DNG) Pictures, ie via LV with no shutter action, I thought I would carry out some experiments this weekend. 

Unlike ‘normal’ photography, IR photography is best undertaken in the brightest of bright sunshine, as we are capturing the reflected IR photons from the sun. Thus there are three sweet times to take images, not two: the golden hours of sunrise and sunset for ‘normal’ photography; and midday ‘golden period’ for IR.

Until the heroes at Magic Lantern tweak the Silent Picture mode, I’m a little limited to timelapses where the light doesn’t change drastically, like is does at sunrise or sunset. Timelapses taken when the light is changing by large amounts requires one to adopt the, so-called, holy grail technique; where you intervene in the timelapse taking and make exposure (step) adjustments.

Magic Lantern offers another approach, whereby you use Auto-ETTR. But, as the Silent (DNG) captured images currently don’t have any exposure EXIF data, I am limiting myself to timelapse sequences where the light is pretty much constant, ie I’m not using A-ETTR at the moment.

So far my workflow looks like this:

• Focus and compose the camera; 
• Put the camera in manual exposure and manual focus;
• Use Auto-ETTR to set the ‘best’ exposure; 
• Set the ML timelapse settings, I aim for 24 fps in the final video; 
• Set Silent Picture mode to on; 
• Put the camera in LV;
• Start the capture sequence; 
• Go and have a cup of tea; 
• Move the DNG images on to the PC; 
• Use EXIFToolGUI to put back in the missing EXIF data;
• Create your video in LR/LRT.

The above may look complicated, but it is not. Also there are many refinements you can make. For me, LRTimelapse (http://lrtimelapse.com ) is a great companion to LR. In addition I recommend David Milligan’s Adobe Bridge script for deflicker (which works without EXIF data): http://davidmilligan.github.io/BridgeRamp/

 

So the proof is in the pudding, as they say. So here is a simple (and rather crude) IR video that I made this afternoon. Clearly I need more experiments!

Moving on: literally!

Like many photographers I am intrigued by videography, but not enough to spend much time on perfecting the craft. However, I have been attracted to the ‘middle ground’ offered by timelapse, ie taking 100s or 1000s of still images over an extended time period, and ‘stitching’ these together in a video, ie temporal bracketing.

 

But also like many photographers I have been ‘worried’ about the additional stress on my shutter mechanism. Once again, however, Magic Lantern comes to the rescue, in the form of RAW video capture from Live View, ie without a single mechanical shutter actuation.

The secret here is 'Silent Picture Mode', where the ML team discovered how to pull 14-bit RAWs (DNGs) from the LV process, albeit limited to about 1930x1140 image size, on my 5DIII. Coupled with being able to adjust the frame rate, between a fraction of a FPS to about 30 FPS, the still photographer has several new options. Here are a couple of examples.

First, by invoking the RAW LV capture, I can set the frames per second to, say, 10, thus allowing me to capture RAW (14-bit) images at, in this case, 10 FPS. The limit is the card-write buffer and on my 5DIII CF cards I can capture 14-bit RAW bursts up to 28 frames, following which the camera needs to write to the card. It is then a simple matter to bring these images into Lightroom, play around with the 14-bit data and, say, export as layers in Ps-CC and, just to have a bit of fun, create, say, a GIF sequence (see below, which is a handheld burst capture of our cat, Polly’s, twitching tail).

Second, by using the ML intervalometer, with the RAW DNG LV mode, I can capture single image (1930x1140) 14-bit RAW timelapse sequences without a shutter actuation. The attached (scaled down video) is a 240 image timelapse I took this morning at a 5 second interval.

If video not showing click here

The post processing is simple with LRTimelapse ( http://lrtimelapse.com/ ), although there is a trick you need to do in Lightroom, to ensure the right EXIF data is associated with each file; as the DNGs that come out of the LV capture don’t appear to have any metadata. The trick is to use LensTagger (http://www.essl.de/wp/software/lenstagger-lightroom-plugin/ ).

So, once again, Magic Lantern has provided three great in-camera features: an intervalometer, RAW burst capture up to about 30FPS (for about 30 images), and shutterless timelapse capture. 

Can it get any better!

Pilgrimage

During a recent trip back to the UK, I decided to undertake a ‘pilgrimage’ to the home of William Henry Fox Talbot (11 February 1800 – 17 September 1877). 

Talbot was the British photography pioneer who invented the calotype process, a precursor to negative-based photographic processes of the 19th and 20th centuries.
 

Lacock is mentioned in the Domesday book, when it had a population of 160–190; with two mills and a vineyard. Lacock Abbey was founded on the manorial lands by Ela, Countess of Salisbury and established in 1232; and the village — with the manor — formed its endowment to "God and St Mary". 

Lacock was granted a market and developed a thriving wool industry during the Middle Ages. Reybridge, and a pack horse ford, remained the only crossing points of the River Avon until the 18th century. 

At the Dissolution, the Abbey and estate, including the village were sold to William Sharington, later passing into the Talbot family by marriage. 

Most of the surviving houses are 18th-century or earlier in construction. There is a 14th-century tithe barn, the medieval St Cyriac's Church, and an inn dating from the 15th century and an 18th-century lock-up.

In 1916 Charles Henry Fox Talbot bequeathed the Lacock estate to his niece, Matilda Gilchrist-Clark, who took the name of Talbot. The estate was given to the National Trust in 1944 by Matilda Talbot – comprising 284 acres (1.15 km2), the Abbey, and the village.

Visiting Lacock was another opportunity to experiment with the Magic Lantern Dual-ISO capability. 

All the images here are Dual-ISO, hand-held shots, ie no bracketing.

Experiment, but have fun

This last weekend was an opportunity for a couple of Brits to experience a local US Civil War re-enhancement. Of course New Mexico was a Territory back then, and us Brits were communicating/trading with both sides!

 

It was a great day out, but what was the experiment? 

Some will have already guessed it was to do with Magic Lantern, and on this occasion I wanted to see what dual-ISO would do in bright sunshine. In another words, what would an extra 3Ev of in-camera shadow recovery look like?

Some photographers would consider carrying a flash to ensure shadows, especially around faces, would not be too blocked; but, as I have said before, a ML enhanced Canon allows you to travel light.

In addition, Alex over at ML has just released his latest version of cr2hdr in a 20-bit version: just download it from here http://acoutts.com/a1ex/cr2hdr-20bit.exe and replace the current cr2hdr in the dual-ISO plugin with this one (but change the name to cr2hdr.exe.

Here is one image that was shot with dual-ISO at 200mm. The base exposure was 1/200, ISO 100 at F/4. The dual-ISO setting was 100/800, ie every other line in the image was captured at ISO 800. 

For those that don’t know what a RAW dual-ISO looks like, I have included a JPEG of the RAW input image.

To ensure I get the image I want, I have also told ML to only take every other image at the dual level. In other words I take two shots of every scene, resulting in one of the images being ‘normal’ and one a dual-ISO capture.

Bottom line: I must say, if your image can tolerate some reduction in resolution, dual-ISO looks like something that might be worth doing ‘most of the time'!