Sorry about the box name I am at the library and can't check the actual name. Any way the box opens and you see a red spot in the middle and green with numerous colour around. How does one use this application. What am I looking at. What is it I am aiming for and what should the image look like? etc etc etc? Can anyone tell me in lay language awith indepth description please. I don't have aclue with this item. StevenA
I think you can safely ignore the FFT box. As I understand it, Registax breaks up the image into its frequency components--high frequency=fine detail, low frequency=large scale detail. The image in the FFt box is just a representation of the various frequencies in the image. The reason for doing this (I think) is that it is easier to align the frames when they have this representation.
Geoff
I am looking into this as well as I do not fully understand it too, I believe it is important to get proper alignment. My recent imaging of the moon found misalignment with changes to the FFT settings, but I still haven't fully understood everything about it yet.
Graham is on the money. You must alter the size of the FFT until you have a small red dot, but not too small. It's a bit of a guessing game but with practice, you'll hit apon the optimum size.
Reading the manual will explain as to why better than I can.
Ok, from my understanding of this box, it sets the feature size that registax will use in your images for its alignment. If you make this number smaller then registax will use larger features in your image and vice versa.
The central red dot gives you a clue as to what feature size it's set for, as you make the numbers bigger this red dot gets smaller.
You can assume that the fft filter will blur your frames (only a copy of the frames, not the real ones) so that features smaller than this red dot are blurred out and not used for alignment.
The correct value of this box depends on your individual data - ie how large the usable features are in your images and how much noise (small scale random features) you have.
You can set it by trial and error - start with a small number like 5 or 6, and then watch the alignment boxes as registax goes through its align phase - if the boxes seem to be moving and tracking on the features ok then you're good. If the alignment boxes seem to be jumping around too much then this number is too big and it's locking onto random noise. If the alignment boxes are not moving enough (or not moving at all) then the value is too small and registax is ignoring the smaller features completely.
My experience is that registax almost always chooses a bad value for this box, I always have to open and reset it to something suitable for my data.
My experience is that registax almost always chooses a bad value for this box, I always have to open and reset it to something suitable for my data.
cheers, Bird
Yep me too always have to adjust it as well. I now for smaller number of frame use manual alignment, whereas webcam spend ages trying to get the best FFT.
Any way the box opens and you see a red spot in the middle and green with numerous colour around. How does one use this application. 
What am I looking at. 
What is it I am aiming for and what should the image look like? etc etc etc? 
Can anyone tell me in lay language awith indepth description please. 
I don't have aclue with this item. StevenA
