There are not enough stars picked in the image. At least 6 stars are needed.

Software Siril
1

Hello.
I am new to Siril.
I am doeing photometry with EOS200D f=200mm.
I have cropped 8 images, and want to plate solve.
But I get repeatedly the error message in the topic.
Can anyone tell me what went wrong?
It is probably explained somewhere else, but where?
From the log:

00:01:43: Sequence loaded: cropped_st (0->7)
00:02:16: Findstar: processing…
00:02:16: Execution time: 485.66 ms.
00:02:16: Found 10 stars in image, channel #1
00:02:54: Findstar: processing…
00:02:55: There are not enough stars picked in the image. At least 6 stars are needed.
00:02:55: Plate Solving failed. The image could not be aligned with the reference stars.

We have wonderfull clear skyes in Denmark
Yours
Søren Toft

2

Hello and welcome!
Maybe the stars are a bit faint, or too much elongated? Please take a look at the configuration window for star detection, the same as PSF analysis. Change the parameters and run the automated detection from the same window to see which parameter better fit your images.

3

Thank you for your suggesstion.
I have tried that, but it is something different.
I find 10 stars with findstar / Dynamic PSF.

I am new to Siril, so it may be something obvious (for the old-timers).
Hej from Søren

4

We need to see your image,
But Siril needs at least 6 stars to perform a platesolving.

5

It can be found here.
[www.astoft.dk/r_cropped_st.ser] (http://www.astoft.dk/r_cropped_st.ser)
(307 MB)
Yours
Søren

6

Got it, but now explain me what do you want?
You don’t need to platesolve each frame to do photometry. Generally we only platesolve the stacking result.

Then, you can perform photometry without doing platesolving.

7

Thank you. Your information is very helpful.

You ask, what I want to do?
I want to observe the variable star R Crb in all four layers of my EOS200D,
and compare the instrumental magnitude with the comparison star and the check-star:

R Crb 15 48 34 +28 09 29
HD141352 15 47 41 +28 28 44 V=7.430 (B-V)= 0.471 (Comparison star)
HD140913 14 45 07 +28 28 13 V=8.060 (B-V)= 0.612 (Check star)

I hope to do this with a precision of 0.005 mag, if possible. Stetson observed with an precision of 0.002 mag, but on much fainter stars.
When one looks at the photometry of AAVSO, the errors in B and V are huge compared to Stetson. Even in the transformation standard cluster M67.

I don’t expect Siril to do the transformation from Canons RGB to Johnsons BVR, but I would like to get the instrumental magnitudes with 3 decimal places. In the file STARS.csv I can see, that the format is only 2 decimal places. [After doing Analyse → Dynamic PSF]

Has anyone made a “road-map” for an observer like me?
You have most likely made fine documentation on this. Where?
My french is rather rudimentary, but google.translate is a fine help, if you know what to translate.

Thank you for making this wonderful astronomical software.
Yours
Søren Toft

8

Here an example of photometry for exoplanets, which is quite the same:

9

I cannot hear the sound.
am I the only one with that problem?
Søren

10

No, there’s no sound.

11

Is the answer to the original question in the headline this simpel:

Platesolving is not for sequences but for the stacked image. (after registration)

Is it allowed to answer the question one self?
Søren

12

If the video has no explaining words, then if feel it difficult to understand what goes on.
Just for your information.
But thanks for a brilliant software. :slightly_smiling_face:
Søren