Barely able to split at 120x, but it was a clean split in momenets of better seeing. Both members appeared a blazing orange-yellow. I did not detect any hint of the green colors reported by other observers (or for that matter, any other color). I then went to 240x with the barlow; although the images were pretty smeared, it was cleanly split, only a few seconds apart. Still both stars appeared OY to me. 
 

Split at 83X but close. Diffraction rings touching but disks split. 

166X provided the best view, clearly split. Both golden in color, 
with the companion slightly dimmer than the primary. 

PA estimated to be 120. (not measured) 

A splendid double. Orange-red to my (male) eyes. At X149 I felt I could drive a bus between the two stars. In the fleeting moments of good seeing there was clear black space between the pair. At x86 a playing card would have separated them, at x55 a piece of paper. 

At the lower two powers the best view came when the clouds covered the stars! The lack of glare from the brighter star and the lack of diffraction rings meant there were two very clearly defined and separate pinpoints, even at X55. As the clouds thinned the stars tended to run into one another at the lower power. Not merging but more of a figure-8 and if I'd been sweeping quickly through the field I could have overlooked the pair. 

At X149 a delightful double regardless of the clouds. If only one of the components had been blue (one of the few other colours my weedy male eyes can distinguish) ... if anybody is starting a best-33-doubles in the northern hemisphere, Algieba gets a vote from me. 
 
 
 
 
This time I decided to see how low I could go and still achieve a split. For this I used my lowest power eyepiece, a somewhat poor quality "Far East" 32mm Plossl. This gives X33 with my 5" Tak and elongate stars away from the centre of the field. 

I couldn't get a split with the bare eyepiece, though Algieba was clearly elongated. Remembering my experience of the other night with the clouds I tried a 90% neutral density filter (aka Moon Filer). Bingo - I could just see two components. Not easy, but definite once I got my eye in (and my head aligned with the optical axis). 

I then went through my other filters. Red did nothing. Yellow and blue even less. And then I tried an Orion Green "58". Easy-peasy a very clear and distinct split. I hopped back and forth between the NDF and Green and green was best by a long way every time. I don't know if this is because the density of the filer was just so, or if the colour was just what was needed. 

I suspect that with a good quality 32mm Plossl I would be able to split Algieba without a filter. I'm looking to buy a 50mm 2" filter for sweeping the summer Milky Way (Comet Bren!). This will give about X21. If Leo is still around when I get it I'll see what it makes of Algieba. 
 

Transparency-- 4 out of 10 
Limiting visual magnitude-- 3.5 
Temperature:  40 F 

Telescope: Celestron C-8 
Eyepiece: 12.5mm Micro-Guide with Barlow (419 x) 
 

Measures: 
It was discovered by William Herschel in 1782.  The orbital period is 618.56 years (Rabe, 1958). 

Earliest measure in 1828 (2.5" @ 102). 
Other measurements for AB: 
 
1940- 4.0" @ 120 
1960- 4.2" @ 121 
1980- 4.3" @ 123 
2000- 4.4" @ 125 
2020- 4.5" @ 127 

Measures listed above are the 1990 set. 
 
I made five pairs of separation and PA measures for AB using the 
Micro-Guide and got an average of 4.81" in PA 124. 

For colors, I noted gold for A and B, and white for C and D. 

The AB pair also contains a spectroscopic binary (star A) and is a 
member of the Gamma Leo group. 
 
The A and B stars are both infra-red sources. C is AD Leo, a flare star. 

The system is 126 light years away (251 times as bright as the Sun). 

2 deg NW is the radiant point of the Leonids (maximum on Nov. 17, with periodic variations in intensity of 33 years- the debris from comet 
Tempel-Tuttle 1866 I).  Next maximum: 2032. 

Although it is certainly a fine double star, I think AB is somewhat 
over-rated.  Personal opinon, no science here. 
 

Ambience: Several companions viewed this object, including two 
ladies, and while variation in colour of secondary was noted no clear-cut 
colour could be established. Sky so dark at times the Magellen Clouds 
stood out like pieces of cotton wool and Omega Centauri could be seen 
as a non-stellar naked-eye object. The Dark-matter Emu, which trails 
from the Southern Cross to Scorpio could be clearly seen when Scorpio 
had risen about 40 degrees. The coal-sack was a striking dark blotch 
but only three stars could be noted within. Evidence that this dark 
sky was not at its best. 

At 80X a cleaner split (during times of steadiness). Both components were a very rich, dark orange color and close in magnitude compared to other doubles in this constellation. 

During observations of Leo tonight, I was amazed by a bright Iridium Flare. I confirmed the sighting as Iridium 62, with a flare magnitude of -3 (not too shabby!) 
 
 
 

General Comment: After the flu and 3 weeks of cloudy weather it was great to get out with the scope again. It was partly cloudy with holes in the sky. Algeiba is a beautiful double but I could only see them as white. With the doubles in Orion I didn't spend any time trying to estimate the PA. After stoping the drive to ascertain the westerly direction I then estimated a PA of 120º which is quite close to the listed of 123º. I used the clock face suggested by Tom Teague. At 80X I could just begin to split the double; however at 167X it was a clean split.