Motion Blur - Bosch Security Systems

APPLICATION NOTE | DINION XF CAMERASUse of Dinion XF Camerasto Reduce Motion BlurApplication DescriptionThis Application Note describes the use of Dinion XFcameras to reduce motion blur.IntroductionMotion blur is one of the curses of CCTV. In virtuallyevery still picture taken from recordings of incidents,the details are unsharp due to the relatively slow shutterspeed, 1/50 or 1/60 sec, used in standard CCTV cameras.As soon as the subject is moving through the pictures,the image is unsharp, making identification moredifficult or even impossible. Similar problems arise inindustrial automation projects and automated systemssuch as number plate recognition.Using High Speed ShutterAs every photographer knows, preventing motion bluris simple. Just increase the shutter speed and the motionis frozen in the picture. However in photography andCCTV you still need the same amount of light to getthe correct exposure. Increasing the shutter speed meansincreasing the illumination level or the size of theaperture used to compensate for the shorter exposure.Indeed this has been common in many cameras.It has been possible to fix a high shutter speed andeliminate the motion blur, at least as long as therewas enough light.However with a fixed shutter speed,as the light level goes down, once the lens is fully openedand the AGC has reached its limit, the video simplydegrades until it is no longer usable.The solutionThe solution to the challenge of getting the imageswithout motion blur for as long as possible is achieved inthe Dinion XF cameras as a result of a number of featuresthat work together to enable optimal performance.Default Shutter ModeIn the default shutter mode of the Dinion XF camera theuser can set the shutter speed minimum to e.g. 1/250 sec.As long as the sufficient light in the scene, for the AutoIris lens control and automatic gain regulation toproduce a full video signal, the shutter remains fixed atthe default value. Only when the light fails does theshutter control take over and increase until the standardvalue is reached. Hence video without motion blur isavailable for as long as possible, yet the full range oflighting conditions can be covered.Security you can rely on

APPLICATION NOTE | DINION XF CAMERASSuperb Sensitivity and XF DynamicIt is perhaps obvious but using the faster shutter requiresa larger aperture and consequently less depth of field.Overall sharpness in the image is also a function of depthof field. The higher the sensitivity the sharper the imageproduced. The default shutter speed is used longer andsmaller apertures are used. The superb sensitivity andDynamic range of the Dinion XF ensures optimumperformance.Lens WizardUsing large apertures means that focussing needs to bemore accurate than when smaller apertures are used.The Bosch Lens Wizard enables fast accurate setting ofthe (back) focus.Remote Set UpUsing the Bilinx communication and the cameraconfiguration software, fine tuning of the system canbe performed without the need to go the camera head.Apart from the physical installation, the camera canbe fully set up remotely e.g. from using the monitoringcamera configuration software running on a PC orLaptop and communicating directly with the camera overthe standard video coax cable. The resulting picture canbe viewed directly on the monitor. The camera modes canbe fine tuned if necessary to ensure the optimal defaultshutter speed for the application.Typical Default Shutter SpeedApplicationSpeedRetail stores, offices, general surveillance 1/100Car parks, stations, traffic 1/250High speed traffic, motorways 1/500Production line observation 1/1000High speed production process 1/10000User bene•tsUsing default shutter allows sharper images to beproduced. The difference can be seen immediately onthe monitor but is more important when looking at stillframes from recordings and in automated processes.Typical system components1/3˝ 1/2˝Colour cameras LTC0485 LTC0610Day/night cameras LTC0495 LTC0620Monochrome cameras LTC0385 LTC0510CoaxCoaxI/FUSBOffline set up screen of the Dinion XF cameras.Default shutter is set to 1/500 sec.A typical setting for traffic surveillance.Bosch Security SystemsFor more information please visit:www.boschsecuritysystems.comData subject to change without notice | Printed in The Netherlands | 2004 - 9922 141 01641en