Leica’s first digital camera, the M8, required an IR Cut filter and there are many forum discussions about the B+W 486, the Heliopan and Leica’s own IR Cut. The following 2007 thread from the Leica forum is reasonably brief, and some of the participants had used both the B+W and the Heliopan. As usual there is no consensus. It appears that Schneider/B+W has changed the 486 coating since this discussion took place:
https://www.l-camera-forum.com/topic/28 ... -any-info/The Heliopan site contains this statement, which also appears to be applicable to the B+W filter: “This dichroic coated specialty filter should not be used with extreme wide angle lenses.” Apparently these filters can cause a colour cast when used with quite wide lenses. The DVInfo thread (above post) discusses this.
The Schneider True-Cut cuts at 750, although there's also a 715 and a 680. The B+W cuts at 680. This is the Heliopan chart, which Robert Neissner posted in an earlier thread:
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