QHYCCD

QHY8L pattern noise

Sniuk

QHY8L pattern noise
« on: March 28, 2021, 06:08:14 AM »

Trying to get the most of my QHY8-L , I'm wondering if there's a way, setting or proceedure to not have this pattern noise.
Seems to be ver consistent everywhere..
This three crops are from a master dark, a master flat and master Dark flat and also a 15min single light frame  crop

They all have that weird noise pattern around that when processing is sort of annoying..

Usig latest SDK, gain 0 offset 132 and Normal speed download.

Since it doesn't seem to disapear after post processing

Any way I can get that to go away? or perhaps make it better? I guess is inherent of the CCD itself...but can it be fixed to get cleaner images?

Thank you ;)

Carles.

Yuki

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Re: QHY8L pattern noise
« Reply #1 on: March 28, 2021, 10:26:40 PM »
There should be no way to improve at present.

Sniuk

Re: QHY8L pattern noise
« Reply #2 on: March 29, 2021, 03:57:09 AM »
There should be no way to improve at present.

Thank you for your answer.

Do you mean that "at present" no, but maybe future yes? is this perhaps an issue that can be fixed by firmware or something? Would be really great if it could : )   it is a great camera, but noise component still hard to fix...

or if you have any  suggestion on how to stack or calibrate to get that better. I've found so far that stacking with Siril on the default "OSC preprocessing scrip" I get better results than with usual DeepSkyStacker settings.. but still noise is there.

Let me know if you can look into it! ^^

Thank you!
Carles.

Yuki

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Re: QHY8L pattern noise
« Reply #3 on: March 29, 2021, 08:58:14 PM »
Sorry, the camera won't have new firmware.

We have no other suggestions, we can only suggest you to  take more dark frames to stack.

Best Regards



Sniuk

Re: QHY8L pattern noise
« Reply #4 on: March 30, 2021, 01:03:02 AM »
Sorry, the camera won't have new firmware.

We have no other suggestions, we can only suggest you to  take more dark frames to stack.

Best Regards
I see, Well I understand, I guess is a too old device..

OK, I will try stacking more Darks.
more dark flats/bias won't do anything? Currently using 51 dark flats. 

thanks

Kind Regards

Carles

Yuki

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Re: QHY8L pattern noise
« Reply #5 on: March 30, 2021, 09:29:04 PM »
51 dark flats are enough.

There should be no better way.

Best Regards

Yuki

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Re: QHY8L pattern noise
« Reply #6 on: March 30, 2021, 09:30:45 PM »
You can send me a FITS.

My colleague will check it.

BestRegards

Sniuk

Re: QHY8L pattern noise
« Reply #7 on: April 01, 2021, 05:12:38 PM »
You can send me a FITS.

My colleague will check it.

BestRegards

Thank you
https://mega.nz

In this link theres darks flats dark flats and a single 900sec sub (not debayered)

Have a look and let me know if you see anything weird or that can be better

Kind regards

Carles
« Last Edit: April 07, 2021, 01:34:58 AM by Sniuk »

Yuki

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Re: QHY8L pattern noise
« Reply #8 on: April 01, 2021, 09:50:54 PM »
Dark field doesn`t have problem.

Best Regards

Sniuk

Re: QHY8L pattern noise
« Reply #9 on: April 02, 2021, 04:30:38 AM »
Dark field doesn`t have problem.

Best Regards

Then what you think is that? Could it be interference in the cable or something ? Or is that noise normal for this sensor ?

Kind regards

Yuki

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Re: QHY8L pattern noise
« Reply #10 on: April 05, 2021, 09:16:06 PM »
Yes, it is normal for this sensor.

But there seems to be something wrong with your bright field processing. I can see some "borders".

Best Regards


Sniuk

Re: QHY8L pattern noise
« Reply #11 on: April 06, 2021, 11:41:03 AM »
Yes, it is normal for this sensor.

But there seems to be something wrong with your bright field processing. I can see some "borders".

Best Regards

Hi,

Do you mean the flat frame has border ? Where ? Can you show me ?  Maybe is because the driver ?or NiNa?

Regards

Yuki

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Re: QHY8L pattern noise
« Reply #12 on: April 06, 2021, 08:55:37 PM »
It looks like there's something wrong with the flat frame calibration.

Maybe you can capture some new flat frames.

Best Regards


Sniuk

Re: QHY8L pattern noise
« Reply #13 on: April 07, 2021, 01:34:05 AM »
It looks like there's something wrong with the flat frame calibration.

Maybe you can capture some new flat frames.

Best Regards

Hi,

I don't see anything wrong there.
That is am stack of around 200 frames, with dithering
And field of view a bit displaced. It needs to be cropped before processing.


Yuki

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Re: QHY8L pattern noise
« Reply #14 on: April 07, 2021, 08:35:40 PM »
Then there should be nothing to improve