Autostakkert alignment points

[knobby]

Hi Peeps,

hope everyones having a great bank holiday weekend ...

being the saddo that I am, I'm reading up on alignment point positioning.

What do you all do ?

I've read that for planets the boxes shouldn't be near the edge and the box size seems to make a difference too.

So what are the collective wealth of experience at SGL thinking ?

[Bizibilder]

For planets the box should not, as you say, be near or at the edge.  The align boxes should, however, have a generous overlap.  You can best achieve this by placing them manually.  For the moon - or any image that "fills" the frame - it is easiest to use the automatic alignbox positioning button.  As for "rules" on alignbox size, I'm not too sure - I use a box size of 60-80 for the moon and try to go for about 140-200 boxes on an image of roughly 1200 x 900 pixels.  Different sources seem to suggest different sizes!

All I can add is that too many small boxes (theoretically these should produce the finest detail) simply extend the processing time for little advantage,  too few big boxes may produce a "soft" image with some loss of fine detail.

Here is a quote from an AS2 tutorial:

"The AP size is the size of each individual alignment box that will be placed on the image. The size of the AP you should choose depends on the quality and resolution of the image. For high resolution, you want to use a small AP size versus a larger AP size with lower resolution images. In this case I choose for a size of 40. Eventually, the minimal brightness of the APs can be set when choosing to automatically place the APs. It indicates the minimal brightness of the background the automatically placed APs must have at least. After setting that, click Place APs in Grid to have AS!2 place the APs on the image. "

The tutorial can be found here:

http://www.astrokraai.nl/tut/guide_dennis_put.htm

[knobby]

Cheers Roger, I'll have a read of that tut.

What I've found is that with good data, the differing processig makes a difference but when the planet is wobbling all over the place it doesn't seem to make much difference ...

'Rubbish in = rubbish out'