QHYCCD

Blooming problem with QHY12

Blooming problem with QHY12
« on: October 22, 2012, 10:20:19 AM »
I got my second QHY12 and have a problem with the new camera, which did not
occur with the other model (actually the old camera did only work from time to time, so I got a new one - thank you for that to QHY!)
.
I have heavy blooming all over the picture with bright stars.
I use a C14 with the HyperStar (f/1.9)
Clamping is checked off
Gain/offset is 0 / 121
Download is low
Sensor temperature – 20deg C
Used EZCAP and Maxim DL
I changed everything:
Clamping checked, other gain and offset, took additional IR filter, download
speed high actually no improvement.
Pleiades show after view seconds blooming all over the picture.
I f I could change the gain to a value lower than zero, there might be a chance…
There are 2 pictures showing the blooming
one 10s picture
one 5 min picture
both single shots without any correction

I'm using the actual driver (via Ascom) for the QHY12.

Any ideas?

BR
Peter

sorry,
I forgot to say, that I have this blooming even on pictures with not that bright stars.

The pleiades show the problem very plainly.
The blooming is on all pictures I made till now.
« Last Edit: October 22, 2012, 02:52:28 PM by cpt.peter »

Re: Blooming problem with QHY12
« Reply #1 on: October 22, 2012, 10:24:31 AM »
Ah, I see the infamous hyperstar 'Abyss Alien' artifacts. I gave up trying to image the Pleiades with my hyperstar. Any bright target really. Sorry, I don't know how to solve the issue you're reporting.
All the best,

  Sander

Takahashi EM-400 - Edge HD 1100 - HyperStar 3 - WO M110 - FR-III/TRF 2008
QHY-8, DSI, QHY 5L-IIc, IMG0H mono, PC164 video
PixInsight, Nebulosity, DeepSkyStacker, PaintShopPro X2, PHD, FireCapture, Autostakkert

Re: Blooming problem with QHY12
« Reply #2 on: October 22, 2012, 10:27:47 AM »
Hi Sander,

yes you are right.
Pleiades are very difficult or actually not possible with the hyperstar.

But they show very good the problem I have.

BR
Peter



b71

Re: Blooming problem with QHY12
« Reply #3 on: October 22, 2012, 02:17:35 PM »
Hello Peter,
I have this effect as well imaging with my c9.25 at f/4 and using binning on nebulae with bright stars.
Eg rocking horse image I posted here. I mount CCD north up and change Dec a few times and remove these effects with sigma median stacking. I remember also having some success with this procedure: You could also remove the nebulae by cutting below certain value adu and removing stars using mosaic. This leaves the bleeding. apply this to the raw images like it's a flat master.
All this is assuming the bleeding is within the specs of the ccd. You mention you previous CCD did not have  this bleeding. I don't know if the CCD manufacturing changed or the previous CCD had anti blooming (like my exview) and this one lacks this. This is for qhy12 experts. If however it's all within specs, this might help.
Best wishes,
Bart

b71

Re: Blooming problem with QHY12
« Reply #4 on: October 22, 2012, 02:48:27 PM »
I meant using opacity, not mosaic.

Re: Blooming problem with QHY12
« Reply #5 on: October 22, 2012, 02:51:37 PM »
Hi Bart,

you wrote:
"I don't know if the CCD manufacturing changed or the previous CCD had anti blooming"

this is what I suppose.
For me it looks, as if there is no anti blooming in this camera.
A friend has an camera without the anti blooming gates and it looks nearly like this.

But this is not what I was looking for.

The picture is made in 1x1 binning

Peter

Re: Blooming problem with QHY12
« Reply #6 on: October 22, 2012, 03:45:27 PM »
Hi,

there should be no need to tricks to get rid of the blooming as this is an ABG sensor. Hopefully Dr Qiu will respond soon and suggest a driver tweak or something else to prevent this from happening.
All the best,

  Sander

Takahashi EM-400 - Edge HD 1100 - HyperStar 3 - WO M110 - FR-III/TRF 2008
QHY-8, DSI, QHY 5L-IIc, IMG0H mono, PC164 video
PixInsight, Nebulosity, DeepSkyStacker, PaintShopPro X2, PHD, FireCapture, Autostakkert

b71

Re: Blooming problem with QHY12
« Reply #7 on: October 22, 2012, 04:03:47 PM »
Hi Peter,

I see now, you also have severe bleeding at 10 seconds. This would not seem normal, so indeed I suspect something wrong.

Disregard my imaging routine, this should be for imaging with subs of a few minutes on nebulae with very bright stars (e.g. mag 6)

Bart

Hi Bart,

you wrote:
"I don't know if the CCD manufacturing changed or the previous CCD had anti blooming"

this is what I suppose.
For me it looks, as if there is no anti blooming in this camera.
A friend has an camera without the anti blooming gates and it looks nearly like this.

But this is not what I was looking for.

The picture is made in 1x1 binning

Peter


QiuHY

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Re: Blooming problem with QHY12
« Reply #8 on: October 22, 2012, 10:44:13 PM »
Hello,

      There is a POT for blooming control. You can try to adjust it . The POT is in the retangle board. You can messure the default voltage of the POT(the voltage on POT screwer to GND)
And then try to increase/decrease it. You can connect the camera to a telescope and use the ground light to try this.


Best regards,
Qiu Hongyun

Re: Blooming problem with QHY12
« Reply #9 on: October 23, 2012, 01:16:54 AM »
Hi Dr. QuiHY,

sorry, I do not trust myself to do this.

The camera is brandnew and bought in Germany.
So do you think astrolumina is able to take care of this?

BR

Peter


Re: Blooming problem with QHY12
« Reply #10 on: October 23, 2012, 04:53:25 AM »
Hello Peter,

We can give it a try but we need some more technical advise from Qiu.
Sent you the details about handling in a separate mail.

Regards,

Michael
Michael Breite
astrolumina
your QHY distributor in Germany, Austria, Poland, Switzerland, BeNeLux and Namibia

Re: Blooming problem with QHY12
« Reply #11 on: October 23, 2012, 08:54:11 AM »
Hello Dr. QiuHY,

is that shown in my pictures
blooming
 or
any readout artifacts?

BR
Peter

QiuHY

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Re: Blooming problem with QHY12
« Reply #12 on: October 23, 2012, 09:39:24 AM »
Hello,
     It is just the blooming. Should adjust the blooming control POT to remove it.

Best regards,
Qiu Hongyun

Re: Blooming problem with QHY12
« Reply #13 on: October 23, 2012, 05:17:31 PM »
A little disturbing that a new camera wasn't adjusted properly in the factory, right?
All the best,

  Sander

Takahashi EM-400 - Edge HD 1100 - HyperStar 3 - WO M110 - FR-III/TRF 2008
QHY-8, DSI, QHY 5L-IIc, IMG0H mono, PC164 video
PixInsight, Nebulosity, DeepSkyStacker, PaintShopPro X2, PHD, FireCapture, Autostakkert

Re: Blooming problem with QHY12
« Reply #14 on: October 24, 2012, 01:20:33 AM »
Hello Qiu,

We need a detailed instruction how to fix the blooming.

Thank you,

Michael
Michael Breite
astrolumina
your QHY distributor in Germany, Austria, Poland, Switzerland, BeNeLux and Namibia