20200613 CaK Sun

I just barely recall that I had a mask on the lens long ago and then being removed later.
I think I will try to add a mask back and see if the image quality improves.

Turned the eq mount by hand and tried to speed up the scan and got an alien shape sun.

Added some black stickers inside the new SHG tube and stray light blocker on the lens, I can capture the image of the sun today.
The result seems acceptable, although the scanning speed is still very natural and low (0x).

I just captured the pinhole image, and now suspect that the aberrations are from the cheap lens.
The previous good image could be due to part of the lens being blocked by the original tube and reduced some aberration.

Both the grating and collimator are old parts that once did create good image quality.
I think I will try to rotate the collimator and check again.

I replaced the slit with a pinhole last night, and checked the 0 order image.
There was some blur on the edge, while some red in the vertical direction and some green in the horizontal direction.
I tried to tilt the lens but no big help. Now I have no idea how to solve the problem...

Because my SHG is based on Littrow design, it can easily introduce some coma + astigmatism aberration.
The slit I am using is fixed-width glass slit, I think I need to remove it first and replace the grating to a mirror to check the problem.

I am struggling to tune my SHG back for better image quality but the results are still disappointing.
I think I have to disassemble it and check each element to make sure they are all in good condition...

I've forgotten the "Horizontal mode" checkbox myself, it seems still work without the tick. It is suggested to use SER format rather than AVI because it seems won't crash for larger/wider videos and also support 16bit per pixel which has higher dynamic range. It seems the "o" doesn't show correctly ...

I can process the video after converting and rotating the AVI to SER.
I only program to process horizontal lines, so you need to capture the lines horizontally.

Merlin66 wrote: ↑

Tue Jun 09, 2020 2:08 am

Wah,
I've sent you an email with the SLiM errors, and sent a copy of the AVI file (930Mb) to dropbox
https://www.dropbox.com/s/rrjtee31vwf1h ... p.avi?dl=0
Ken

I just downloaded this file, it is "AVI" format.
Can you try mono "SER" instead?

Is there a line number or which function causes the error?

Excellent and sharp images!
How do you manage to tune the focus of the telescope, I wonder?

Excellent and sharp images!
How do you manage to tune the focus of the telescope, I wonder?

https://drive.google.com/file/d/1Gnfkx2 ... sp=sharing

Hi Merlin, are you able to download the file from the above link?

Wah, I've sent you an email with the SLiM errors, and sent a copy of the AVI file (930Mb) to dropbox https://www.dropbox.com/s/rrjtee31vwf1hbp/Sun_110135_pipp.avi?dl=0 Ken I just experienced the error myself this morning, and found that it should be a setting problem. I mistakenly set the project a...

I am not sure about the bandwidth, what do you think based on the image below?
BTW, I've found that my eq-mount was vibrating during the scan, it is another important factor making the image blur.

I got up early in the morning for the Venus ring, but failed.
So I changed the equipment to my smallest spectroscope (combined with Vixen 80ED as an SHG) for the first light.
Although I think the focus was not at the best position, I am still quite pleased with the results.

Not from OVIO, but tailor-made from China some years ago.

Two improvements:
1. Slit fixing method
2. Print direction

I can't go anywhere and only can see a partial eclipse at home.
Just wonder if any group members can reach the center line.

I know the coronavirus has shut down the traffic worldwide.
But I still wonder who is going to capture the flash spectrum of the upcoming annular eclipse?

The refill filament has arrived and more parts have been printed out.

Yes, this is from a new all-in-one SHG, with longer focal length than before. Hope it can give better spectral resolution.