What I have learnt from creating photograms is that one is working with chance. The physical composition one creates in comparison to the photogram is completely different. One has to keep in mind that one is capturing the shadows of the objects as it is the part where light does not hit.
I personally enjoy working with layers as it creates mid tones and depth into the compositions. I don’t like harsh colour contrasts where the photogram is made up of complete white and black as this causes the work to look flat.
To create layers one would need to uses various semi-translucent materials such as plastic bags, negatives, balloons filled with air or water, coloured plastics, salt, sugar etc.
The more time the composition is exposed to light the more the paper will burn, resulting in a darker photogram.
When working with layers one must keep in mind that the objects in direct contact with the photosensitive paper are the ones that will be more pronounced.
Examples of my work below will help one get a better idea of what I am talking about.
This was my very first photogram.
When creating this composition I was expecting to see the actual objects imprinted on the paper. Instead I got this mysterious ghost like shape. Not knowing exactly how photograms worked, my composition resulted in a complete abstraction of reality. I consider this photogram as a happy accident and according to me, it is more beautiful to create ambiguities then a reproduction of reality.
As you might have guessed too much light was let in resulting in a very dark composition. There is no fixed amount of time of light to pass through, it depends on the composition.
This composition consists of a shell in a plastic bag. Since the plastic bag is transparent light goes through it, burning the paper. The shell was not directly in contact with the paper so light would take longer to travel to it.
In total I used 4 seconds of light exposure. I divided the timing into two so that I could move the shells positioning. Unfortunately I needed to use less time as I only had one layer. If I used 2 sec of light instead of 4 sec, the shell would have been more pronounced. Next time I would need to use a coloured plastic bag so that light would not be able to travel through completely.
For this composition I placed the objects on the right directly on the photosensitive paper. Since they are directly in contact with the paper a more pronounced shadow is produced resulting in a pure white colour. This time I used a blue plastic bag. As it was more opaque it showed in my photogram. The colour gradient changes depending on the opacity. The grey tones occur with semi translucent objects. The start was then placed over the plastic bag creating the third layer. Since the plastic bag is coloured, it acted as a separating layer. The bag separated the objects in contact with the paper and the star. This created depth and a colour gradient.
Here I used 1.5 sec of light exposure. The timing was decided by using a test strip. This is done by covering the scene with a thick paper and moving it a bit to the right every 0.5 seconds.