Day 3 - experimenting with a Lightbox

Written By Martin Newham

An are I have not really tried out in photography is high speed close up work.

About a year ago I got a cheap little LED lightbox which has reflective sides and a port above to shoot looking straight down. I used this to take product shots for my art website, but have not really used it since.

As I was walking back from my morning coffee I thought I would have a go at photographing a closeup of a glass of water - its on theme but is also pushing me to try something a little different. Plus its was something a little less obvious that popping down to the beach (although that one is definitely on the cards!)

So I got set up with my 90mm 2.8 macro lens and a little light box

(technically in this image I’ve got the tamron 28-200mm lens on which I cannot recommend enough!)

This was very much a lesson in understanding depth of field vs light source intensity.

With the macro lens the focal lengths I was looking at to get the whole image in sharp focus were too high - as far as f22.

Lower f stops resulted in some blurring so one of the things I thought I would try was a focus stack.

I shot from above (obviously!) and started with the rim of the glass in focus, the slowly extended the focus out for each image until the base was sharp. in total I took 6 images.

I then selected them in Lightroom and imported them into photoshop as layers.

Selecting them all I auto aligned and then auto blended as a stack, which resulted in an OK focus stack. The rim is still a little soft and I thing the merge may have gotten a little confused by the cut crystal, but for a first attempt using software that was not really designed for it, I think its an ok image.

One major challenge was getting perspective right - even in this image I am not perfectly vertical to the subject - the bottom side of the glass is slightly fatter than the top side.

I must have spent an hour slowly moving things around and this is something I will have to come back to, but it really dies make a difference

After that I began to experiment with fast frame imaging to try an capture water as it dropped into the glass. I quickly realised 3 things:

1) A cut crystal glass was too distracting, I needed a clear one

2) I dd not have enough light to get the iso low enough and maintain a good speed and focal length

3) Focussing on the point where the water hits its HARD with the shorted focal lengths

In the end I was not able to get any decent images of water dropping, so will have to return to that. I did then think to pour water into a glass from a jug and was much happier with the results:

This was a great first attempt - I need stronger lighting and a lot more practice but it was a fun morning of experimentation!

Martin Newham
Next

Day 2 - a chance of rain