interclips picture quality ratings

To offer detailed information about the picture quality of the available stock footage clips there is now an advanced rating system. The rated items include sharpness, color/contrast and image steadyness. All new clips (published ater Sept. 22th 2007) show the new rating matrix by default. Older clips will be rated during the next weeks.

The interclips team pays attention to a broadcast quality level principally. Offered clips have passed quality test to meet TV standard at least. Each single clips gets published after a manual visual quality check regarding picture sharpness, color/contrast and image steadyness. You recognize broadcast quality clips by at least three stars at each quality rating bar.

If a clip has less than three stars at a specific picture quality level, the clip content is very unique (e.g. showing pictures of a specific country or of a special event). Such clips can be used in video projects; But picture quality is not at its optimum.

Sharpness

Rating:	Description:
	Image not sharp
	Image partly not sharp / slightly unsharp continuously
	Image sharp, Broadcast quality
	Image sharpness very good
	Image sharpness excellent (only possible with Ultra HD cameras or in computer animations)

Alle Aufnahmen müssen zunächst einmal scharf sein - es sei denn die Unschärfe wird beispielweise im Rahmen einer Schärfeverlagerung oder als bewußte Reduzierung der Tiefenschärfe/Schärfentiefe eingesetzt. Clips mit pumpendem Autofokus oder falscher Schärfeeinstellung werden nicht akzeptiert.

At standard definition (DS) the used camera type is very important for image sharpness. Broadcast quality can in most cases be only achieved by using a 3CCD camera. In most cases clips from cameras with only one CCD chip will not be accepted.

At high definition (HD) cameras new image sensor technologies and various compression techniques make it difficult to recommend a specific camera type for shooting. Just note that not every "Full HD" camera (as printed in the manufacturer's product sheet) delivers Full-HD quality to the final video file on your editing system.

Color/contrast

Rating:	Description:
	Color/contrast continuosly weak
	Color/contrast partly weak / slightly weak continously
	Color/contrast good, Broadcast quality
	Color/contrast very good
	Color/contrast excellent (only possible with HDR techniques or with computer animations)

Clipped skys, no details in shadows, weak colors. These are typical quality problems which result in refusion of uploaded footage. Especially when using electronic video cameras (SD and HD) you must pay attention to the very reduced dynamic range in relation to the human eye. Possible solutions at interior shoty is sufficient lighting. Pol-, ND- or Gradiation filters can help you during location shots.

Image steadyness

Rating:	Description:
	Image jitters/ shakes continuously
	Image jitters/ shakes for a short time / slighty continously
	Image steadyness good, Broadcast quality
	Image steadyness very good
	Image steadyness excellent (e.g. by using motion control systems, or in computer animations)

Completely steady images can only be achived by using a tripod. But there are various tripos on the market. Especially professional tripos with fluid heads are recommended.

At footage clips showing crane shots, pans and tilts, steadycam-like pictures, drive or hand-held recordings interclips rates the quality of the movement. Demands of good image steadyness are higher at HD shots, because HD shots are often targeted for productions on large screens. And slight shakes result in much larger shakes onto larger screens (cinema or projectors).