Well... Tonight was one of those very rare steady nights for me. It was slightly misty so no good for Deep Sky, hence I thought I would turn my attention to another attempt at Sirius and the Pup.
I Started out with the C5 using an 18mm homebrew crosshair eyepiece. The plan being to hide Sirius behind a cross hair to reduce glare and improve my chances. A quick look at Mars told me the crosshairs were about 10 arc seconds thick, so I had a good sense of scale.
At around 20:15 (UT) Sirius was low and had its usual 'flaming appearance', but I was getting occasional glimpses of the first ring so things were looking good. However despite half an hour of just hiding Sirius behind the cross hair I could not spot the pup.
I was about to give up, but a movement slightly jogged the scope and Sirius was now blazing in full view... and I could not believe my eyes. For about 1 second I noticed a little point of light just trailing behind Sirius and then the 'flames' washed out the view. The little point of light would briefly re-appear every few minutes or so confirming the sighting. As Sirius got higher (about another half an hour later) the seeing became very steady and I could hold the Pup in view for 4 or 5 seconds at a time.
I thought I wonder if the little C90 will see this... Sure enough it can! - Nothing like as easy as it was in the C5 and it required very careful adverted vision, but over about 15 mins I got 5 glimpses of the Pup for about a second or so.
I'm not sure if I would have seen it first in the C90, as knowing exactly where and what to look for, plus both scopes having the same focal length and eyepiece really helped (It's so much easier to see again once you have first spotted it).
I also tried a 10mm Plossl (and I really wanted this eyepiece to work, since it only cost £3 new!!!), but no - Just one possible brief glimpse in the C5... The 18mm (only 70x) seemed to be the correct eyepiece tonight.
Then the clouds rolled in...
But hey, in what must be ~30 years I've never seen the Pup before... and to be able to glimpse it in the little C90 really surprised me. I won't forget tonight.