Issue with the BatchPreProcessing Script

[Eddy Timmermans]

Hi all,

I recently made my first series of photographs for at  least 9 months.
I made 60 lights of 60 secs, 10 darks and 10 flats.
I had to ditch the flats because they were no good.
I then tried to stack the lights and darks with the script.
Everything went fine until the script began star aligning.
I got the error message : No stars detected when the program analysed my reference frame.
Even in RAW format I can see some stars.
Can anyone tell me what could be wrong ?
Below is the reference image.
Thanks Eddy

[Juan Conejero]

Hi Eddy,

Difficult to say without looking at the actual raw images. Try with the new noise reduction option of StarAlignment:

- On the BPP window, select the Lights page
- Click Registration parameters
- Set noise reduction = 10 or 15 (for example)

I'm pretty sure this will allow you to register these images.

[Eddy Timmermans]

No, that didn't work either.
I think the lights are no good.
When I do an STF there are horizontal lines all over the picture.

I will try again when the weather clears.
Greetz
Eddy

[Eddy Timmermans]

Is there a way to "score" light images in PI like in DSS ?
DSS was able to stack my last series, but the individual scores were pretty low, which made me almost sure I was going to run into trouble with PI.
But the stars looked pretty good this time so I had hopes.
So I think some of my 60 images should be good enough to try the whole BPS and see what it can do.
Or do I check the images one by one ?

Eddy

[Juan Conejero]

Hi Eddy,

Take a look at Mike Schuster's SubframeSelector script:

http://pixinsight.com/forum/index.php?topic=5712.0

This is an absolutely wonderful image analysis tool. It can rate your frames based on many criteria, including FWHM, star eccentricity, noise estimates, and arithmetic combinations of them. The script can also reject bad frames automatically and copy only accepted frames to a destination folder. You can also generate graphs, numerical tables, FWHM and eccentricity maps, etc.

[Eddy Timmermans]

Thx Juan,

I downloaded some of these tools.
The stacked image via DSS had a FWHM median of 6. I don't think this is very good. Usually via DSS I get 4.5 or better. :-(
Now I have to figure ou how to put them in my favorites.
I can use then via Execute Script, but I don't find them in the list.
I'm sure there is a solution somewhere in these pages :-)

BTW I have the impression that the new BPS script is much faster than the previous one and I am looking forward to creating my first image using nothing else but PI.

Eddy

[Juan Conejero]

Hi Eddy,

To add a script to your Script main menu:

- Select Script > Feature Scripts

- On the Feature Scripts dialog, click the Add button.

- Navigate to the folder where you have uncompressed the script and select that folder.

- Click the Done button.

Now the script should be available under your Script main menu. In the case of SubframeSelector, it will be available as Script > Batch Processing > SubframeSelector.0.9

Hope this helps.

[Eddy Timmermans]

Hi all,

I just tried again to stack lights, darks and bias frames with the BPP script.
This time I used the score I got in DSS, to select and check the best images.

My previous reference image had a FWHM value of 4.89.
When I used the best score in DSS, te FWHM was 3.05.

Using this image as the reference image, the whole process worked flawlessly. And did a pretty good job at creating a nice image with only 10 lights.
Of course there was quite some noise.

Is there a way to use the FWHM script on a large number of images ? I tried with the image container but that didn't work.
And checking the images one by one is rather tedious.

So now I await the next clear night and try to make good images.
But the problem I had is solved !!!

Thank you,
Eddy

[pfile]

[Eddy Timmermans]

OK. I'll try that thx
Eddy

[Eddy Timmermans]

The result : My first image processed completely with PI
Only 30 frames selected with FWHM<4

[jerryyyyy]

This subscript selection script seems like rocket science.  I have 26 O-III subs and there is certainly a wide variability of the images.  Looking at Pfiles output my FWHM values are a lot larger 3-5.... assuming the scope was focused, I guess this is just an argument for a better scope .  But at least I can cull out the worst. 

[pfile]

those images happened to be from a 200mm lens pointed at the veil nebula, so the FHWMs are going to be small. in fact i've seen as low as 1.2 with that lens. these were 1200s exposures and the tracking/guiding was not so good, so the stars are a bit oval.

with poor seeing and longer focal lengths you can expect fatter stars... so probably no reason to ditch your OTA.

rob

[jerryyyyy]

those images happened to be from a 200mm lens pointed at the veil nebula, so the FHWMs are going to be small. in fact i've seen as low as 1.2 with that lens. these were 1200s exposures and the tracking/guiding was not so good, so the stars are a bit oval.

with poor seeing and longer focal lengths you can expect fatter stars... so probably no reason to ditch your OTA.

rob

Looking for an excuse....

[Eddy Timmermans]

Hi

Last night I stacked the 40 best images together with 100 bias frames, 37 lights and 10 flats.

The script worked perfectly. But of course a 1h exposure leaves a lot of noise.
However, I didn't succeed in removing a black spot right of center.
I don't see in in my master flat, or bias .

Could it be that it was a dust particle or smudge that was removed while I was going inside to make the flats ?
I made these max 15 minutes after the last light.
I used a hair dryer to remove dew. Is that allowed or do I have to make the flats with the dew still on the lens ?

Anyway, I am very pleased with the script.

Eddy