Tonight I went after a couple of Orion's easier doubles: Mintaka, (Delta Ori, HR1852), and Sigma Ori (TYC4771-01196-1). Mintaka is the end belt star farthest from the sword in Orion and is easily visible to the naked eye even with a nearby almost full moon. Sigma orion is conspicuous between the other end of the belt (Alnitak or ZetOri) and the nearest sword star (42 Ori). Sigma Ori is a group of 3 stars: TYC4771-01196-1, TYC4771-01195-1 (13" from Sigma), and TYC4771-01194-1 (41.6" from Sigma). TYC4771-01195-1 was easily visible with 10mm EP and visible with 25mm. It was about the same brightness as the 3rd companion to Sigma. The group form a 5 star arrow-like asterism that is conspicuous. One of the five, TYC4771-01205-1, also appears to be a double with companion TYC4771-01204-1 that is about the same brightness with a separation between the two about 13". SkyChart says the separation is only 8.5". It was easily visible with 10mm EP. This group was identified as 'Struve 761' at the Spirit of 33 website. The Delta Orion double is easy to see with 52.3" separation. Sigma happens to be on Reising's top ten binaries list.
I also downloaded and installed the WDS2000 catalog but it seems to include doubles that are way too close for my 8" to resolve. It simply shows the direction of the companion(s) but doesn't seem to show a star.
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