Hello,
Thank you all for your posts of appreciation – their contribution certainly extends the enjoyment of my imaging activities.
Splitting Sirius A & B is no doubt challenging, something I haven’t yet done visually. Although the images in the previous posts reveal the separation between A & B, they may also be misleading for anyone attempting this visually, as they show the Pup quite well in a couple of the panes.
CCD sensors are very efficient. They only require a few grains of light to clump together at the same x-y position on a few frames, just above the level of any background noise. Then, sophisticated image processing applications can latch on to these dim grains of light to reveal the presence of an object too dim to be easily seen by our eyes.
In my case, seated comfortably whilst looking at a computer screen with the exposure, Gain and Gamma optimised to suppress the blinding glare of Sirius A, is quite different to looking through an eyepiece. After acquiring Sirius on the screen, a good candidate for the Pup revealed itself after a few minutes of comfortably watching the display, despite other “clumps” of light occasionally appearing in differing positions, which were probably seeing artefacts.
Having established the likely position of the Pup, rotating the CCD camera 90 degrees gave me the advantage of knowing precisely where to look next. Sure enough, in those fleeting moments of steadier seeing, the Pup revealed its presence once more. Similarly for the 180 and 270 degree positions.
In review, some of the key success factors were:
- Target “movement” is a great aid in finding an object. Now you see it (when the seeing steadies), now you don’t (when the image turns to mush). The unsteady atmosphere acts like a blink comparator!
- Sitting comfortably, with eyes relaxed looking at a static screen proved very effective in latching onto the fleeting appearances.
- Being able to configure the various image capture settings to tease B out of the overwhelming glare of A is a big plus – something the eye cannot really do at the eyepiece.
- Rotating the CCD camera helped confirm I was actually seeing the Pup as it re-appeared in each new location.
So, here is a 4 pane collage showing 4 frames from the same AVI, revealing how fleeting the Pup can be, even to the tireless, efficient and unbiased CCD chip. This is as close I can get to representing how this may look visually, at the eyepiece.
Cheers
Dennis
