Sun Nov 12 plus registax6 questions

[tilbrook@rbe.ne]

Hi,

Managed some imaging of the sun today before the cloud rolled in.

Equipement, Canon EOS 1100D at prime focus, 200mm F/6 newtonion.

Now to quetsions on Registax 6.

After mucking around, and finding Registax 6 doesn't like mpeg images, I converted to AVI and no problems.
Has any body else found this?

After sorting this out I went through the process to get a final stacked image of ten frames. The image seems less sharp than a single frame.
My question is, is there a step / steps I'm missing, or is this totally due to seeing conditions?

Any advice appreciated.

Cheers,

Justin.

[sheeny]

G'Day Justin,

Daytime seeing is pretty poor compared to night time - lots of thermals in the atmosphere, etc. So 10 frames is not very many to stack and the seeing differences between each frame will soften the stacked image.

This is why most planetary and solar imagers use a video camera. We capture a lot of frames (500 to 1500 say) then we use the software to cull out the poor quality frames and the frames which are distorted by seeing, before stacking. After stacking, apply wavelets to sharpen up the image and bring out the detail.

I lot of people stack a lot more frames than me, but I typically stack my best 100 to 250 frames. If I'm really struggling with poor data, I'll come down to my best 30. Below that I reckon you are better off picking the best single frame and go with that.

Al.

[tilbrook@rbe.ne]

Thanks, Al.

I should of mentioned I was using movie shooting mode. It sounds like I need to use more images for the final stack.

A question, do you use the wavelet function in stacking?

Thanks,

Justin.

[sheeny]

I haven't tried Rv6 yet I'm still using Registax v5. My procedure is roughly as follows:



Capture say 600 frames.
Open the video in Registax and scroll through and pick a sharp frame to set multiple alignment points on, then Align.
Use the Limit button to reject the worst frames.
On the optimise tab Create a new reference frame from the best 10 frames or so.
Apply the most appropriate wavelets to the reference frame before continuing. this should hopefully get you the best frame (hopefully better than any you've captured) to optimise to.
Optimise.
On the stack page, open the Stackgraph. Use the sliders to select say the best 150 or 250 or whatever to stack, and then for each alignment point drag the difference pointer down till you are stacking the best 100 or 150 or so.;)
Stack the image and save it.
Apply wavelets on the next tab and save it on the Finish tab.

The initial limit cull reduces the number of frame you need to process by getting rid of the worst ones.


The Quality slider on the stack graph lets you select the sharpest frames.


The Difference slider lets you reject the sharp frames that are most distorted. A distorted frame will adversely affect the stack just like a blurry one would.;)



:)


Al.