Understanding the ICM effect of camera motion through simulation
Gaining an understanding of how intentional camera movement (ICM) during exposure impacts results is typically a long and arduous undertaking. With so many variables involved the technique has often been described as haphazard or requiring luck. Whilst that may be partially true, photographers can give themselves a head start by using a tool they may already use at home.
Examining the results of simulated camera movements can provide the user a level of familiarity they can use in the field, and although should never be claimed as ICM the same tool can be used to add a creative layer to non-ICM imagery.
Note - the following information is intended for educational use to allow an easier understanding of how camera movement impacts images during ICM scenarios. Although the tools described emulate the effects of ICM there should be full disclosure should such tools be used to create that effect on published work.
All who start their journey into ICM are faced with a major hurdle, learning to understand how subtle changes in camera movement impacts results This learning is typically achieved through lengthy trial and error, but there are tools available in Photoshop that can speed up this essential understanding and without having to leave the home. Although not targeting ICM, tools within the Photoshop filter module can be utilized to simulate the effect of camera movement on a given subject. This allows for experimentation at home and ultimately more informed decisions in the field.
Requirements are basic - all that is required is that an appropriate (non-cm) image is opened in Photoshop, and modified using the tools and controls described below. In this article am going to focus on Motion Blur, a filter that can simulate the effects of the linear pans so often used in ICM. It is suggested that the effects of this type of motion be fully understood before progressing to more advanced techniques.
Photoshop Motion Blur
(Photoshop tabs - Filter => Blur => Motion Blur)
The Motion Blur tool is a simple tool that can emulate camera movement in a single direction. This is a great tool that can mimic the standard motion pans that continue to be the bread and butter of ICM. Experimentation with this tool can aid not only provide the novice with and understanding of movement impact before heading into the field, but I feel is useful to veterans who may want to visualize movements they may not typically consider attempting.
The following controls are available in this tool that directly equate to camera movement.
Controls and ICM equivalent actions
Angle - this simulates the direction of camera movement as the shutter was released. Note that the angle can be typed in or adjusted via dragging the mouse on the compass control
Distance - equates to the distance of camera movement during the exposure. Greater distance (camera motion speed) = increased effect
Base Image
I have selected the image below as a base to demonstrate the effects of the motion blur filter. I was initially drawn to the bold and linear lines of the trees in the field, and experimented with a vertical panning motion. The results of my in-the-field ICM attempts are used as a side-by-side comparison to show how the use of filters in Photoshop may produce similar results. This indicates that testing in Photoshop really does mimic effects in the field, and can be used to lessen the learning curve.
Below is the original image - used as the base for all Motion blur filter images. These are then compared to actual field ICM shots of the same scene. The Motion Blur control panel is included for a visual reference.
The following series displays actual ICM images taken on location, compared to those where Photoshop motion blur simulation was applied to the original. Results are remarkably similar, and I believe show that experimentation with appropriate images can improve an understanding of how the effects camera motion angle and speed can impact results.
Slow camera motion during exposure (both camera motion and simulation direction following that of tree trunks)
Original non-ICM base image
Photoshop Motion Blur control panel
Actual Field ICM image - taken at 1/50th sec
Equivalent simulated motion blur in Photoshop
Faster camera motion
Actual Field ICM image - taken at 1/8th sec
Equivalent simulated motion blur in Photoshop
It can be seen in the above examples that a vertical motion that follows the subject can produce interesting results, and that simulation of this motion in Photoshop can accurately match the results found in the field. However, we may wish to experiment with different motion directions to get an idea of what results we can expect when shooting with our camera. To this end the Motion Blur filter in PS offers a simple way to predict results of varying angles on an image.
The following two images show the simulation results of a horizontal blur motion (distance changed between) when applied to the same base (non-ICM) image. It can be seen that in this instance the subject loses both form and recognition, leading to a more abstract image. This would have a totally different impact on images that have strong horizontal forms (eg seascapes).
Simulated horizontal movement - slow
Simulated horizontal movement - fast
Conclusion
I believe this demonstrates how the Motion Blur filter can accurately predict results in the field when using ICM linear pan techniques. I would recommend those interested in gaining a greater understanding of ICM experiment with varying images (suggest trees, waterscapes to begin with) and just have fun with it.