Assingning calibration frames to lights doesn´t work

@rodljo Hi Johannes,

Could you please share 5 lights and 5 of each type of calibration data? The instructions for sharing data are to the top of each forum page:

Thanks, Wouter

@wvreeven Hi Wouter,

thanks for your replay. I created the directory as mentioned in your post and uploaded the files. I uploaded all of it in fits, if you need the Raw of the calibration frames, I´ll add them as well. 

Looking forward to your answer 🙂 

Best, Johannes

@rodljo Thanks for uploading the FITS files. I will need the RAW calibration files so please upload 5 of each as well. Thanks in advance!

@wvreeven  Uploading finished. I hope it suits your needs 🙂 Thx again for your help!

@rodljo Thanks for the quick follow up. I had a look at your data and, indeed, the flats are not applied. The reason is not the file format but the ISO value. The lights, darks and bias are all shot at ISO 2000 and the flats on ISO 100. This will not work. You either need to make sure that you have ISO 2000 flats or to make sure that you have dark flats of the same exposure time and ISO as the flats.

By the way, how do you create the flats? What light source do you use? They look like this:

The histogram doesn't look very well. The three color channels should have sharper peaks and no trailing tails to the left. Another possibility is very, very strong vignetting in the corners but i have never seen that before.

Also, the exposure time of 0.00625 seconds is much too short. You should aim for exposure times between 1 and, say, 5 seconds. Do you dim the light source with a white t-shirt or any other way when you shoot the flats?

Hi Wouter,

wvreeven   thanks for your help and time. I must admit, I´m quite confused now. I never ever before used the same ISO for the Flats as for the Darks/Lights etc. and it always worked fine...That´s new to me. What is also confusing is the fact that nothing was applied, darks were also not used for the integration...as well as flats. I also tried old Bias which had the same ISO as the current flats... Are you sure it can´t be about the file fomat?

Best 

Johannes

@rodljo To be honest, I still think there is something wrong with the flats but the different file formats may be an issue as well. @mabula will have a look as well.

Okay, looking forward to it, thanks!

@rodljo Mabula and I had a quick look. There are two (additional) issues with the data. Fitst of all, the image dimensions for the FITS files are different than for the ARW files:

As you can dee, the FITS files are 4256x2848 pixels and the ARW files 4288x2848 pixels. That way, APP doesn't know which pixels of the calibration files to use for calibration of the lights and therefore chooses not to apply them.

Secondly, the FITS headers for the lights show that they were shot with NINA while the EXIF data of the ARW files indicate the use of ICLE-7S. So it seems you have taken the calibration frames directly with the camera. This is a problem as well (apart from the different dimensions of the resulting files) since the camera software may treat the files differently than NINA does, resulting in unusable calibration data. As a rule you should always use the same software for taking lights and calibration data, so in this case NINA.

HTH, Wouter