QHY8L - Good Idea/Bad Idea?

[Guest]

First thing is that the raw .fit images seem to be gray and not color...

Hi Andrew

Have you pre-processed  and then debayered the .fits?

[russellhq]

The stacked image normally looks washed out, you need to enhance the colour. What bayer matrix settings did you use? The QHY8L bayer pattern is GBRG.

Also, a file size of 80Mb seems to indicate you have a colour file. I can have a look when I get home.

[neodude]

Hi,

I have done it with DSS after:

http://deepskystacker.wikispaces.com/How+to+stack+QHY8+images

I set as camera the QHY8 (there is no QHY8L)..

then, with the stacked image i use FITS Liberator and save each of the 3 planes as red,green,blue as tif, then process in Photoshop..

Now i think i see some colour in PS, but the white circle i guess it is from the lack of flat frames...

Also the center of M31 is very bright have to exercise with processing i guess...

Andrew

[Zakalwe]

Hi,

I have done it with DSS after:

http://deepskystacker.wikispaces.com/How+to+stack+QHY8+images

I set as camera the QHY8 (there is no QHY8L)..

then, with the stacked image i use FITS Liberator and save each of the 3 planes as red,green,blue as tif, then process in Photoshop..

Now i think i see some colour in PS, but the white circle i guess it is from the lack of flat frames...

Also the center of M31 is very bright have to exercise with processing i guess...

Andrew

:confused:  No need for all that faffing.

Set the De-bayer manually in the Option part of DSS. As Rusel has said the correct one to select is "Generic GBRG"

[Spikey]

I have to boost the blue channel and weaken the red/green with every process - there are a couple of ways I've found that work really well and mean it's not such an issue

As for the LP filters adding red - I ran without the neodymium filter at Kelling and had the same sort of processing task as with it - lots of red and the blue very weak.

Happy to discuss if you'd like to send a pm - don't want to kill this thread by going too far "off piste" LOL!

David

As the owner of an original QHY8 I would quite like to see your process  flow for doing this.

Any chance you could start a new thread in imaging processing section?

[Guest]

As the owner of an original QHY8 I would quite like to see your process  flow for doing this.

Any chance you could start a new thread in imaging processing section?

Sure - just working on a tutorial now - I'm going to post it on my website under the how to section

David

[russellhq]

Hello,

last night i managed to image the M31, unfortunately the image looks pretty bad after calibration and stacking in DSS.

there are 6x300sec light, 5 darks, 20 bias; no flats..

My gain was 6 with 114 offset, temperature set at -10 C.

First thing is that the raw .fit images seem to be gray and not color...

I am not sure what i am doing wrong.. please see the stacked image at the below link, but it's pretty big around 80 MB.

I would appreciate any advice..

https://drive.google.com/file/d/0B7abYsk7FXHRZlNQMHdSMkdEZUU/edit?usp=sharing

Thank you,

Andrew

Something doesn't look right at all with that image. I think something has gone wrong with the stacking.

Double check the bayer setting for FITS files. It needs to be GBRG.

Also, try stacking just the lights using "average" mode and "no background calibration". Save the file as a 16bit TIFF and upload that to Dropbox and we can have another look.

[Guest]

I've started a new thread on Battling the QHY8 Blues in the image processing section 

Remember - this is just something I found works for me - it may be wrong - if you find that it is let me know :-)

Here's the link on my website

https://sites.google.com/site/welfordobservatory/home/how-to/boosting-blue-in-qhy8-images

David

[nightcasper]

I've started a new thread on Battling the QHY8 Blues in the image processing section 

Remember - this is just something I found works for me - it may be wrong - if you find that it is let me know :-)

Here's the link on my website

https://sites.google.com/site/welfordobservatory/home/how-to/boosting-blue-in-qhy8-images

David

Thanks for that will have a look and give it a try.

Dave

[Zakalwe]

I've started a new thread on Battling the QHY8 Blues in the image processing section 

Remember - this is just something I found works for me - it may be wrong - if you find that it is let me know :-)

Here's the link on my website

https://sites.google.com/site/welfordobservatory/home/how-to/boosting-blue-in-qhy8-images

David

The 8 and 8L have different Sony sensors though. The QHY8 and the 8Pro have the ICX453 sensor. The QHY8L has the ICX413.

Neodude needs to start by setting the correct Bayer matrix setting if he is using DSS to stack. If he have set the settings as QHY8 then it will be de-Bayered incorrectly. If it is de-Bayered incorrectly, then all the post-processing in the world won't correct it.

[neodude]

Something doesn't look right at all with that image. I think something has gone wrong with the stacking.

Double check the bayer setting for FITS files. It needs to be GBRG.

FITS_Setting.png

Also, try stacking just the lights using "average" mode and "no background calibration". Save the file as a 16bit TIFF and upload that to Dropbox and we can have another look.

Hi,

I have restacked the lights only as you suggested, below is the link with the stacked image:

https://www.dropbox.com/s/k48pvapupv0bjvq/Autosave002.fit

I have played a lot with the images, i am getting some colour in PS, but am also getting a huge circle...i think it's some kind of reflection..i hope flats will solve the issue.

Please let me know your opinion..

thanks a lot to all,

Andrew

[msh1]

Hi,

I have restacked the lights only as you suggested, below is the link with the stacked image:

https://www.dropbox.com/s/k48pvapupv0bjvq/Autosave002.fit

I have played a lot with the images, i am getting some colour in PS, but am also getting a huge circle...i think it's some kind of reflection..i hope flats will solve the issue.

Please let me know your opinion..

thanks a lot to all,

Andrew

I'm just seeing a black picture no data in there at all 

[Guest]

The 8 and 8L have different Sony sensors though. The QHY8 and the 8Pro have the ICX453 sensor. The QHY8L has the ICX413.

Neodude needs to start by setting the correct Bayer matrix setting if he is using DSS to stack. If he have set the settings as QHY8 then it will be de-Bayered incorrectly. If it is de-Bayered incorrectly, then all the post-processing in the world won't correct it.

People seem to be struggling with blue channel balance in both the 8 and 8L

Also, my post wasn't in reply to Neodude's processing issues :-)

David

[Zakalwe]

Hi,

I have restacked the lights only as you suggested, below is the link with the stacked image:

https://www.dropbox.com/s/k48pvapupv0bjvq/Autosave002.fit

I have played a lot with the images, i am getting some colour in PS, but am also getting a huge circle...i think it's some kind of reflection..i hope flats will solve the issue.

Please let me know your opinion..

thanks a lot to all,

Andrew

There is data in there, but it's very very faint. Do you have bad light pollution at your site?

Flats will help, as there is vignetting across the image.

This is a simple screen grab from DSS. I'd wager that this was taken on a night with poor transparency?

[Zakalwe]

Try this DSS tutorial.

http://www.astronomyshed.co.uk/forum/viewtopic.php?f=19&t=1328&p=3168&hilit=deep+sky+stacker#p3168

It explains quite a lot about simple first steps in processing.

[russellhq]

Also looks like you're capturing the overscan area. I don't think there's any need to do that and it might confuse the stacking software.

[russellhq]

Here's a heavily stretched copy of your data.

You have got the bayer settings right but there's not a lot of signal there. Things to improve:

1) You definitely need more data, like 4 hours or more.

2) Flats will make a big improvement as well (not as much as more data though). I find they make the most significant impact to the visual quality of an image.

3) It looks like you have a lot of coma, notice how the stars around the edges all seem to be pointing inwards. Get a coma corrector for your scope e.g Baader MPCC

4) Find a nice dark site to image from (this one is a luxury but makes a huge difference)

[Zakalwe]

Also looks like you're capturing the overscan area. I don't think there's any need to do that and it might confuse the stacking software.

There's a tickbox in EZCAP which will cut this from the output.

[neodude]

Yes,

You both are right on all accounts )

the image is taken in the middle of Bucharest, so yes very much LP.

Also yes it was overscan area, i didn't know what to choose in EZcap.

I am planning on taking your advices and getting also a coma corrector.

I will be back with other images when the weather clears (currently it'\s snowing here )

Thank you all for your help !!

[Zakalwe]

The overscan isnt that important.....DSS will ignore it.

[Gina]

AAMOI has anyone tried removing the CFA (debayering) the QHY8(L)?

[russellhq]

AAMOI has anyone tried removing the CFA (debayering) the QHY8(L)?

I think they have and I think it was done with a solvent (no scratching)

Looking for another project Gina?

[Gina]

I think they have and I think it was done with a solvent (no scratching)

Looking for another project Gina?

Nah... I'm quite happy with my Atik 460EX   I think I would be too nervous about scrapping that much cost   A few tens of pounds on used or partly duff DSLRs from ebay is about as far as I want to go.

[nightcasper]

Recenty posted a 4 min sub to show what the QHY8L can produce here is the stacked version 5 x 240 secs sub. Taken on 24/11/2013 the skies where not the best due to mist and cloud originally had 8 subs but had to discard 3.  Stacked & Processed in PI. Taken with a QHY8L,SW ED80,GT-EQ6,Astronomik CLS Filter (not IR blocked) guided with 9 x 50 finder guider with a QHY5.
Any comments welcome.

Dave

[rob0971]

Looks good to me Dave!