The electronic screens of some bridge cameras do not work as well as the OVF of DSLRs in situations of low light (although some work better, allowing high gain and slow refresh). For bridge cameras with EVFs, the LCD screen might be difficult to see and use for framing in bright daylight. Also, especially with older or lower-end cameras, the screen resolution and refresh rate may be limiting compared to the very high resolution and real time view provided by an optical path in the OVF of DSLRs. Low resolution impedes some forms of manual focusing, but most modern bridge cameras implement a method called focus zoom which automatically magnifies a central frame within the screen (manual focus point) to allow easier manual focusing. A slow refresh rate means that the image seen on the screen will have a fraction of a second lag or delay from the real scene being photographed. The electronic screens used in modern bridge cameras are gradually improving in their size, resolution, visibility, magnification and refresh rate.