18 Jun 2015

Taking photos of groups of children - some tips and observations

Recently I had an assignment to take photos of the several school classes. The final 'product' were the standard group photos of school classes:

Although it looks simple, there are some aspects and potential challenges that require at least some attention.

The location and lighting

Choosing the right spot for a shoot is not trivial, especially when the only available location is a school playground: a lot of open space with the school building as the background. Not very exiting, I'd say. Additional problem was the full sun at this day which would guarantee harsh shadows on the faces of the children. Luckily, at the border of the playground there were some trees that gave enough shadow to cover the whole group. Shadow coming from the tree provided decent light for the shoot: diffused on one side, but bright enough to be able to shoot with the 1/100s, f/7.1 and ISO 200.
Last but not least, the trees served as a nice background for the photo. My setup looked as shown in the picture below:

The bench in the shadow was the main 'stage', while the camera was about 10-15 meters away, put on a tripod (right in the picture) The lens used was 200 mm lens, set to about 135 mm. This focal length was good enough to compress the foreground with the background a bit.

The background was not perfect though. There were still some distracting elements there (like the fence and the bright part of the building's roof. 

This was the moment of a trade off: lighting wise it was the best spot I could get, so I was pretty sure that the most important objects on the photo (children's faces) would be properly lit. The distraction I could eliminate, at least partially by careful composition and doing some post processing.

 The last aspect to take care about was the color of light. Since the shadow was given by the trees, they could cause some color casting. To prepare for it I took several pictures of the color checker placed on the spot. I use X-Rite color checker for this purpose. X-Rite software integrates well with Lightroom  and makes creation of the color profiles quite easy.

The limited time

This is almost always the case at school: tight rhythm of the day: 45 minutes lesson, 10 minutes break, next lesson. So is the time of the photoshoot. Per group I had roughly 5 minutes time: to set up the group, to take 1-2 test photos, do some reshuffling of children, cherry up some of them, calm down most of them, take the final picture. 
Interesting observation is that teachers are not of much help in such situation: they are part of the group waiting for the directions. So it is important to have a plan and be ready to play the role of a 'director' of the shoot. 

Direction and communication with the group

First of all I have pictured in my head the end result. To play safe I applied the simple principles to make the process simple: most people read visual information from left to right and from top to bottom. Another basic principle was to ensure that all the faces are good visible and not covered by other children or other obstacles. Having all this in mind the direction was straightforward: I created 2 rows, ordered taller children to step on the bench, less tall ones to stay on the ground. Then (if required) I reshuffled them to ensure that the rows visually form more or less straight line. 
Again, it is the tradeoff, balancing the certainty of the final shot, the (limited) artistic values of the photo and limited time. 
Each time I was explaining the process at the very beginning: I have noticed that this way I can have children's attention for at least couple of minutes.
To enhance communication I decided to use the trigger cable for releasing the shutter. So I was able to stay next to my camera and have direct contact with the group. It worked well, especially when I had to give some extra directions. For example, it is pointless to say to the group: "and now move 0,5 meter to the left". Instead I was making a step aside asking them to do the same. It worked well.
For the final shot I explained that I will be counting till 5 before taking the shot and was showing the number with my hand. In fact I was taking the actual shot at "3" or "4". This simple trick ensured that they all watched at me (or rather my hand) and I could catch their eyes on the picture.

Watch out the equipment

This is very important, especially when one stays on the playground. The thing is that the children start run and don't watch at the obstacles. So it is absolutely necessary to stand by the tripod and mark your spot this way. Otherwise there is a risk that they tackle the gear. This happened to me some time ago when one of the children run against the light stand with attached flashlight and an umbrella. As a result thereof I had to buy a new umbrella.

27 Apr 2015

Tagging people in Lightroom CC (also Lightroom 6) - some tips

The newest version of Lightroom CC (Lightroom 6) comes with a number of new features. One of them is the automatic face recognition which enables tagging people on the photos. To me it is a very welcome enhancement of Lightroom since it makes possible to keep the records of photographed people in an easy way.
Last week I let Lightroom scan for the faces in my main catalog. It turned to be a long process. Granted, my main catalog contains over 80000 photos, so a number of faces there is substantial (more than 38000 and counting). And the process of finding faces runs for almost 4 days over all photos.

Finding faces is one thing, putting the names behind them is something else. The algorithms applied in Lightroom do the job quite well and after some time and tagging several names, the application starts recognizing similar faces. But the algorithm is not perfect and I have experienced quite some "missers" (faces that were recognized incorrectly).

So to speed up the whole process a bit I have developed simple workflow that is based on structural elimination of the photos scanned by Lightroom and  use of keyboard shortcuts.

Step number one: eliminate photos of unknown or people you are not interesting in

When looking for people, Lightroom tries to automatically attach the names to them based on the information gathered so far. If it cannot find any similar person the name is left empty and there is a '?' sign below the photo to indicate it. If the name is attached, Lightroom asks the user for confirmation, by displaying for each thumbnail the check- or cancel- mark for confirmation or cancelation, respectively. When the name suggested by Lightroom is wrong one can discard it or remove the particular thumbnail completely from the further analysis. By discarding the wrong name, the faces are returned back to the analysis and Lightroom tries to attach another name to them.
In case of the photos of unknown or unwanted people it is useful to remove them from further processing. So when I have a screen full of thumbnails, I first select all the photos I don't want to process further. Then I simply press Delete key. They are removed from the grid and are not processed by Lightroom. By repeating this step consecutively, the grid will be gradually filled with the faces I want to add to my database.

Step number two: Select the faces belonging to the same person, tag them in one step

Now I select all the faces that belong to the same person. Usual way of selecting is applicable here: by holding Shift and clicking on the thumbnails for continuous photos in the grid or by pressing Ctrl (Command) key and clicking on a single photo. It does not matter how the Lightroom categorized the face: with a guessed name or with a question mark. Once the photos are selected, I press the Shift-O key to edit the name I want to tag the faces with. This name will be applied to all selected photos.

Step number three: Repeat steps one and two until you are done

Some other tips

I have noticed that for large grids Lightroom has some troubles with rendering them, which slows the process down. So it is better to navigate somewhere to the smaller structure in the catalog (a collection, collection set or directory). If such set contains no more than couple of thousands faces, Lightroom renders them smooth.

25 Jan 2015

Dealing with limited lighting equipment - when choices have to be made

It happens every now and then to me: when setting up the lighting for shooting I realise that I would like to have more lighting to achieve the desired effect. Not so long ago I was shooting an event at school where my wife teaches. The event consisted of several parts: some performance on the stage and a mini-concert on a piano (standing off the stage, just in front of the audience)
For the light setup on the stage I wanted to use a well proven setup for boosting the stage lighting. But then I have realised that photographing the piano player will be difficult. I had not enough light equipment to serve both purposes. So I needed to make a choice with my setup: concentrate the lighting on the piano or on the stage.
To decide I looked at the rehearsal of both events. It turned out that the singers on the stage are individuals, so the stage lighting provided for their performance would be enough. To make a sharp, steady shot of them I would have to crank up the ISO settings to the 1600+ regions, but it is not a problem to my camera.
Then the lighting for the piano. I wanted to create some drama during the pianist's performance on one side and show a context of his concert on the other. And to put enough lighting on the player of course, to make him the most dominant element of the picture.

The drama was coming from the stage lighting (a high power tungsten reflector). The light for the pianist was delivered by the SB-900 flash light put inside the Lastolite softbox. To balance the color temperature of the flashlight with the stage lighting I put the full CTO gel in front of the flash light.
So the whole setup looked like that:

The softbox being the extra light source gave enough exposure on the back of the pianist and also provided additional light on the keyboard.

Another advantage of the extra light source was that the piano was better exposed while shooting from another angle.