Lens Wanderings

Category: Photography

  • Photography with Polarised Light

    Photography with Polarised Light

    Introduction

    Photography with polarised light can yield some surprising results. Polarised light can be produced in a number of ways, including when light is reflected from some surfaces, emitted by screens on devices like laptops or by passing through filters made from particular materials, for example Polaroid sunglasses. In normal daily life, you will not be able to notice whether the light entering your eye is polarised or not. However, in this post, you can explore the creative possibilities of using polarised light. Let’s dive straight in!

    What you need

    • A screen to act as a light source. This could be a mobile phone, tablet or laptop screen

    • Polaroid sunglasses, Polaroid 3-D movie glasses or a polarising filter for a camera

    • A selection of transparent plastic objects such as food boxes, a ruler, plastic cutlery or transparent plastic bag like a food bag

    • Finally a person to help hold things or a tripod to mount the camera on

    Laptop, mobile phone, tablet, polarising glasses, and a piece of plastic used for photography with polarised light.

    What to do

    Using glasses

    Set up the light source screen so that it is mainly white for example by displaying a blank window with a word processor on a laptop. Hold the glasses in front of the screen.

    Polarising glasses with incorrect alignment

    Rotate the glasses and look for an orientation where light from the screen is dimmed or blocked completely.

    Polarising glasses with correct alignment

    Using a filter

    Set up the light source screen so that it is mainly white for example by displaying a blank window with a word processor on a laptop. Hold the filter in front of the screen or attach it to your camera

    Polarising filter with incorrect alignment

    Rotate the filter and look for an orientation where light from the screen is dimmed with a blue tint.

    Polarising filter with correct alignment

    Adding some plastic

    Without changing the orientation of the glasses or the filter place some transparent plastic in between the screen and the glasses/filter. You should see coloured patterns due to stress in the plastic from its manufacture.

    A piece of plastic between a laptop screen and polarising glasses

    If you use the transparent plastic bag, cut it into a single layer and then stretch and pull it. Place it between the screen and the glasses/filter and stretch it some more. You should see the coloured patterns change as you pull on the plastic.

    Amazing coloured patterns in a piece of stretched plastic bag under polarised light

    Wrapping up

    I used to teach this effect as part of a physics course. It was one of those lessons that students couldn’t get enough of. Who says physics is boring! I hope you enjoy exploring this exciting phenomenon and here are a few more examples if you wish to take a look.

    Best wishes
    Derek

  • Point of View and Perspective

    Point of View and Perspective

    Introduction

    For truly captivating photography try exploring point of view (POV) and perspective. This means not just snapping with your camera at eye level but stopping and thinking about placing your camera in a different position. Let’s dive straight right in!

    Go low

    Crouch down for a worm’s-eye view as I did here. Don’t underestimate the power of getting low, really low, with your camera and if there happens to be some water around then you kind of get ‘two for one’ with your composition as in this example shot in an alleyway in Bangkok.

    Ground level reflection in a puddle in an alley in Bangkok

    Go high

    Stretch your arms above your head or go higher if it’s safe to do so. In Bangkok there are often conveniently placed walkways and bridges to take advantage of.

    Overhead view of two boats in a floating market in Bangkok

    Go behind

    If there are people near you taking photographs of some scene with their mobiles try getting behind them and include their phones in your shot. A photograph of a group of people holding their phon can make for an interesting composition.

    A crowd hold up their mobile phones to photograph the Mae Khlong market train - monochrome

    This works particularly well at an event or spectacle, as here at the Mae Khlong Railway Market. Indeed if there’s a crowd it’s almost impossible not to include other peoples’ phone screens in your shot. Here I focussed on the mobile screen not the scene in the background.

    A crowd hold up their mobile phones to photograph the Mae Khlong market train - monochrome

    Go close

    If you are in an area where there are metal surfaces, for example a city walkway with metal sides, then try placing your camera right up against the side with the lens as close as possible to the surface. This works particularly well with a mobile phone actually touching the surface. Depending on the lighting and the location you might get something like this or the banner photograph at the top of the post.

    Abstract curved effect with the camera touching the metal side of a city walkway – monochrome

    Wrapping up

    By intentionally choosing your point of view and perspective, you can transform a simple snapshot into a compelling visual narrative, drawing people deeper into the world you’re capturing with your camera. Enjoy exploring POV in your photography.

    Best wishes
    Derek

    Night time long exposure low point of view from the curb side of a road with passing traffic
    Overhead view looking down on a woman pushing a cart laden with vegetables in Bangkok
  • Long Exposure Photography

    Long Exposure Photography

    Introduction

    In this post I will outline the steps in taking a long exposure photograph and give suggestions for what makes a suitable location, like the one above in Koh Samet, Thailand. Basic equipment needed is a camera with a Bulb Mode (usually labelled B), remote shutter release switch, tripod and some ND filters. Let’s dive straight in!

    Procedure

    • Auto focus picture and compose.
    • Switch off autofocus to lock the focus. 
    • In Av mode set ISO 100 and required aperture.
    • Take a test shot and note the exposure time.
    • Switch to Manual mode and apply the exposure settings from the test shot.
    • Use a phone app like NiSi Runner (or the table below) to estimate the ND filter needed to give the required exposure time (see the table and notes below).
    • Attach the ND filter(s).
    • If the required exposure time is less than 30s then in Manual mode:
      • Increase the shutter time by same number of stops as the ND filter.
      • Take the photo with remote switch.
    • If the required exposure time is greater than 30s:
      • Change to Bulb mode.
      • Take the photo with a remote switch.
    Table showing ND Filter values versus exposure times

    Using the table: if the test exposure time is 1/30s and you require 30 seconds then in the first row go down from 1/30s to 30s then across to the left and you see will need an ND Filter Stop of 10.P3

    Notes

    If the light is changing, check the test exposure time with a phone app like Lux. A time of around one minute is usually suitable but down to 30 seconds or maybe up to 2-3 minutes might be needed. A degree of trial and error is usually required. You may find reference elsewhere to using long exposure noise reduction for very long exposure times if this is offered by your camera however I’ve never found this to be necessary and in any case it doubles the length of time for taking the photograph.

    Another suggestion you might find when using a camera on a tripod is to switch off image stabilisation if your camera or lens has it. Again I’ve never found this to be necessary. Finally, it is suggested to fit a view finder cover and taking long exposure photographs. I always forget to do this and I haven’t found an issue with the photographs I take.

    What makes a suitable location?

    Piers extending out into the sea are always good. The older the better. Finding them deserted can be a problem which usually entails a very early start or a very late one. Rocks and boulders also work well as do boats beached at low tide as long as there’s some water around them. If you live in or near a city with waterfronts or riverfronts, then a nighttime long exposure shoot can look spectacular.

    Wrapping up

    If you have not tried this technique before, I hope you get as much enjoyment from it as I did. If nothing else you get plenty of time to relax while taking the photographs and also plenty of exercise hiking around coastlines looking for suitable subjects.

    Best wishes

    Derek