From my research for this section The Beauty of Artificial Light I have decided to try and capture the concept of the ‘blue hour’ as used by Sato Shintaro. (Click for link to research). While I have seen it in images I was unfamiliar of the science of why it happens and wanted to explore the possibilities.
The blue hour is a period light time that appears just before dawn and just after sunset and is named after the sky colour. It happens when the sun is between 4 to 6 degrees below the horizon both in the morning and the evening. It is far more noticeable in the evening as the hour progresses it gets darker so we become more aware of the impending darkness rather than the gradual lightening. It does not last exactly an hour but depending on your position in the world it can be longer the nearer the pole you are and shorter the nearer the equator.
The blue comes from the fact of mixed light in that it is neither full daylight nor is it total darkness because the sun still gives light from just below the horizon. During this time the colour actually changes from blue to dark blue to black as the sun drops further below the horizon and night cuts in. The blue hour is always present but not always available to see as whether can obscure the effect. See link for a diagram and further detailed explanation. http://petapixel.com/2014/06/11/understanding-golden-hour-blue-hour-twilights/
Blue Hour Calculator
I have discovered a Blue Hour/Golden Hour calculator on the net that based on the date and your world location it will calculate the appropriate blue hour times and take the guess work out of things. I have played around with it and it is well done but realistically was not much assistance for the exercise as judging the blue hour was done more by eye. Where it would be good if one were planning for example some travel shots in distant place at some point in the future. Itineraries could be built around this. http://jekophoto.eu/tools/twilight-calculator-blue-hour-golden-hour/
Preparation and Planning
The location I chose was the local university as first explored in Assignment 1 in The Square Mile. This was selected as because of the generally low and wide nature of the architecture of buildings it would allow the sky to dominant it the images. Also from observation there seemed to be many different artificial light sources tungsten, sodium, fluorescent, and LED. I thought this would be interesting how these would sit together in the final image. Of course this was speculation and I had never really worked with combined light sources. I did investigate going into the city but dismissed this because the much taller nature of the buildings while giving off much light did not allow me to explore the sky.
The pictures were really going to be a voyage of experimentation and expected far more misses than hits. I had never really consciously taken night time pictures before other than light trail pictures. I had no idea what the exposure times should be, nor what the white balance on the camera should be. Also would it actually be light enough for the camera to autofocus or would I have to do this manuall?. Finally what shots should I select because there would only be window of about 45 minutes to get this right.
It stands to reason that the blue hour is weather dependent and I had to wait for over a week for the right conditions to appear. Prior to that point it had been stormy, rainy and cloudy. While this did give different photographic possibilities it was not core for this exercise. However it did give me time to explore the very large campus and narrow down possible locations of where to shoot thus saving time on the evening in question.
Because of the expected long exposure time the camera would be tripod mounted. Also my camera afforded me the luxury of a remote control shutter release. This has the advantage of removing any movement in the camera as (a) you do not have to press the shutter and (b) it gives a few seconds delay before the shutter fires to ensure the camera was completely settled. For me sharp images were important as I wanted to repeat the sharpness that you get in daylight but at nigh time. Many an evening picture have I seen that is very dramatic but clearly there is a little movement in the camera. Again this was all hope and I would not know until I had completed the exercise.
If all of that were not enough I wanted to produce some aesthetically pleasing images. I did not just want this to be a technical exercise in taking pictures at the blue hour. I wanted to make the light and the sky to be part of the total composition rather than a technically balanced well exposed picture. Again unsure as how I would do this during the twilight.
The images were taken over a period of two consecutive nights. This was because a combination of practicability in that it took much longer than I expected to set up and experiment, the sheer size of the university campus even though I had planned the activity plus the short window of opportunity. As mentioned before the blue hour was really only about 45 minutes to get that real deep blue colour before it turns to a really dark blue/black. There was no chance for a third night as the weather conditions changed for the worse.
For Day 1 in a way I misjudged my timings as I wanted to capture the sequence of moving from sunset through the blue hour and onto darkness. By the time I had got to the location and set up my equipment made a few test shots, adjusted position etc. the blue hour was well under way. I captured a number of shots I was pleased with and then continued on with taking mixed light images on the campus. I wanted to experiment with timings and exposures and to see how different types on light would reproduce.
The results are show on a slide show here. The initial images are of the blue hour and the rest are of the mixed lighting. Overall I was pleased with the images taken. There were a few technical disasters of completely black frames or where I knocked the tripod. These have been excluded because they do not add any learning value.
For Day 2, I was far more prepared and got to the site earlier. Again a lesson I learned from the ‘mistakes’ of the previous night was to stay in the same location around or near one building and follow the effects of the blue hour on the subject rather than chase the light itself.
Within this set of selected images I have chosen a number that meet my criteria in that I believe are different in their content, show the effect of the blue hour, are technically correct and have an aesthetic quality.
While the campus was busy it seems that the slow shutter speeds have obviated the recording of the people and gives an eerie emptiness almost abandoned to the night feel in the images.
All but no post processing has taken place with RAW images. The have been sharpened a little but no colour balance was changed and they are effectively as they were shot and converted to JPEG for display purposes. No cropping took place either so they all are full frame and as seen.
This was the only image that I have included from the first night. While it can be argued that it is a little out of sequence it clearly shows the affect of the blue hour colour. I like the way the artificial light down-lighters have been purposefully designed so as not to create light pollution. They have been functionally designed just to light the parking area. Detail remains within the blue are and you can see depth and form within the buildings in the background. The lighting on the lamp posts, because it is more direct, creates some harsh shadows.
Taken on Day 2 at the start of the blue hour. In fact the reflection in the building shows that transition between sunset and the blue hour is still in progress. I decided for reflection here because as the sun drops it is directional, therefore in the windows you can see what is happening behind and in the sky above the building the transition to the blue hour has already set in.
It can also be seen in the reflection that the street lights are now on and that the walkway under the building has now been artificially lit emphasizing that change to night time. By chance the advertising on the crane gives a focal point of artificial light, and just above the moon can be seen reflected in the windows. In a way the moon is a strange light source here because not only the moon is reflected light from the sun, this light has also reflected back onto the windows.
Within this shot I have tried to demonstrate different light sources as the blue hour progresses. It was shot from underneath the building. As can bee seen from other pictures this building is just made up of curved lines and as a result the light moves over it in a peculiar aesthetic way. In the courtyard there are small up-lighters designed to reflect light back down from the concrete ceiling. In the rooms on the building it looks on the face of it there are two different ‘colours’ of artificial light. In fact on further inspection (see image 5) it appears to be internal glass walls of the meeting rooms that are creating this effect. The light passing through the thick glass clearly has an affect on the wavelength colour.
Taken from the opposite side from Image 4 looking through the building into where the sun would have set. There are still light areas to the right of the sky where the sun is still having and affect. The moon can be seen and also a star or planet is now visible as the sky darkens. Again in the top right an airplane vapour trail can bee seen. The remaining light from the sun below the horizon is enough to catch and reflect light from the vapour. Inside the building to the right a large TV screen can be seen giving another mix to the light sources.
From a scene from inside the courtyard that highlights further the plane vapour trails. Upon inspection four can be clearly seen in different stages of their evaporation. To the right inside of the building the effect of the glass walls can be seen giving a different colour to what I believe is the same light source. There is an argument that this picture does not add any further information to the blue hour progression than image 4. That is true to some point but I have left it in as I feel it does connect through to image 6 and is an aesthetically pleasing image.
Looking away from the campus over the road into the deepest part of the blue hour. Here it can be seen that the sky is now almost blue/black and the transition phase has finished. Besides the functional artificial light needed to light the bus stop and one of the student rooms there is still enough light coming from the sky to reflect back from the building. Clearly being a white building helps this reflection process. This light must be coming from the sky as there is no other light source around to light this building. Yes light does come from the main building itself but as can be seen in image 7 taken from the same camera position this is some distance away. Looking carefully into the picture and because of the slow shutter speeds used yellow light trails of the passing bus have made their mark on the image. I do like this as a stand alone image in that it does give a feeling of emptiness to the whole scene.
The final image looks back on the whole campus to show the blue hour in totality. What is surprising is that to the naked eye the sky seemed black yet looking at the image there almost still looks the vestige of sunset which is not the case. Somehow some very low clouds are picking up a light reflection. I would argue this is reflected light from the city beyond rather than the sun below the horizon. Clearly there is a difference between the camera deals with the exposure and my eye just focusing on the bright lights of the building. Perhaps waiting for a much longer period of time would my eyes got more adjusted to this final light.
Comparison to Exercise 4.2
For me the daylight shots in exercise 4.2 in showing how the effects of a dull day does not really change the lighting is not a great comparison. Only once throughout the did a small change become apparent. Because of the weather there was no concept of the blue or golden hour (sunrise of sunset) therefore it becomes difficult to compare the quality of light. For me the images in this exercise are far superior to those in 4.2 as they have more of a direct purpose and there is some element of storytelling involved albeit just following the blue hour.
If it is then a comparison of the pure quality of light between the exercises where quality is defined as the ‘distinction between hard and soft light’ then there is clearly a difference. For me those images have a far better cleaner quality compared to 4.2. The mix of the artificial light adds to this effect giving a much harder differentiated light.
I had toyed with the idea to retake the selected images during daylight to do a comparison on the pictures to show the difference in light. While this would be an interesting exercise I am not sure if it would add great value here for this exercise but it is something to bear in mind for a future project or assignment.