#61  
Old 30-11-2009, 08:46 PM
Gama's Avatar
Gama
Registered User

Gama is offline
 
Join Date: Dec 2005
Location: Melbourne
Posts: 1,121
It does look like an offsett. Remember that Nebulosity and Maxim use different figures to represent the offsett and gain.
A gain of 1 and offsett of 65 is NOT the same in maxim. So you cant just enter the same numbers..
Can you post a single sub showing the Histogram ?.


Theo.
Reply With Quote
  #62  
Old 30-11-2009, 09:09 PM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,485
Image capture was in Nebulosity and I used the tutorial from Neb to determine the gain and offset for my camera. Ive attached a sreenshot of a single frame before and after de-bayering in Nebulosity.
Left - not debayered right - debayered
Attached Thumbnails
Click for full-size image (not debayered.jpg)
54.1 KB44 views
Click for full-size image (de-bayered.jpg)
56.8 KB44 views
Reply With Quote
  #63  
Old 30-11-2009, 10:57 PM
Gama's Avatar
Gama
Registered User

Gama is offline
 
Join Date: Dec 2005
Location: Melbourne
Posts: 1,121
Allan, can you send me a Crop of 1/4 the image in a FIT format to my email.
Want to check a few things.
Make sure its NOT converted to color.

Theo
Reply With Quote
  #64  
Old 30-11-2009, 11:50 PM
CometGuy's Avatar
CometGuy
Registered User

CometGuy is offline
 
Join Date: Feb 2005
Location: Brisbane
Posts: 942
Are sure this isn't condensation on the CCD coverglass?

Terry
Reply With Quote
  #65  
Old 01-12-2009, 11:54 AM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,485
Quote:
Originally Posted by CometGuy View Post
Are sure this isn't condensation on the CCD coverglass?

Terry
Absolutely sure as I run a heating element in the camera (new for QHY8 from Theo) and previously I always used a 2" dew heater strip around the front of the camera.
I only use Nebulosity to capture with the QHY8 - dont have Maxim
Reply With Quote
  #66  
Old 01-12-2009, 11:54 AM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,485
Quote:
Originally Posted by Gama View Post
Allan, can you send me a Crop of 1/4 the image in a FIT format to my email.
Want to check a few things.
Make sure its NOT converted to color.

Theo
Theo - file sent to your email. Not colour converted.
Allan
Reply With Quote
  #67  
Old 01-12-2009, 05:06 PM
Gama's Avatar
Gama
Registered User

Gama is offline
 
Join Date: Dec 2005
Location: Melbourne
Posts: 1,121
I checked your file Allan, and under Maxim, it shows a clipped image.
I thought at first, maybe its because you cropped the image, and thus has changed the Histogram position, but i also cropped one of my own images, and the Histogram barely moved..
Attached is the image i got using Maxim to display the image..
Very strange.

Theo
Attached Thumbnails
Click for full-size image (test.jpg)
128.2 KB48 views
Reply With Quote
  #68  
Old 01-12-2009, 06:38 PM
TheDecepticon
Registered User

TheDecepticon is offline
 
Join Date: Feb 2008
Posts: 1,223
One of the images is very noisy. I know there are some capture problems if the TEC is not working well. Is the camera getting warm at the heat sink and the fan blowing warm air? Have you checked that all components are getting their respective power. Why not check out the QHYCCD Yahoo group? You might get some info from there.
Reply With Quote
  #69  
Old 01-12-2009, 09:27 PM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,485
Found the problem. Originally I was using TVDEE drivers but changed to QHY drivers to get the 4x4 binning. Now I find with this installation Im getting a lot of read out noise and the offset settings have to be increased to ~120 to get a pixel reading of ~1000. Previously my offset was 50-65 to get the SAME value with TVDEE drivers. I have gone back to the TVDEE drivers as these give absolutely noise free images.
When I upgraded to the QHY drivers I assumed that the offset settings would be the same- not so at those settings for the TVDEE drivers 65 offset, the ADU reading was 0.
Find it interesting that now Im getting download noise with the qhy drivers and not TVDEE drivers????
Reply With Quote
  #70  
Old 02-12-2009, 12:12 AM
Gama's Avatar
Gama
Registered User

Gama is offline
 
Join Date: Dec 2005
Location: Melbourne
Posts: 1,121
The offsett numbers are not identical, or should i say, they are not absolute, but rather relative to its own formulars/calulations.
The same goes with the gain, its all relative to its own programming.
I use the original drivers from QHY, and i have no noise, and images are fine..
But im glad your back on the wagon..

Theo.
Reply With Quote
  #71  
Old 02-12-2009, 08:14 AM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,485
Theo and others, thanks for your valiant efforts. Ive tried all the available drivers and settled on QHY drivers which I can now use noise free and with 1% Gain and an Offset of 111. When binning from 1x1 to 2x2 and 4x4 the ADU goes from ~350 to ~750 to ~1200 and so this looks like the settings for my camera. With the TVDEE it was 1%Gain and offset of 50. Guess that its a lesson for all to check it if you change your parameters. Noise may have been due to partially seated s video cable not being all the way in.

Allan
Reply With Quote
  #72  
Old 02-12-2009, 08:30 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Sydney
Posts: 22,060
Wow. Pretty amazing how significantly drivers can change the behaviour of a camera. I reckon I'll stick with what I've got now. Seems to be working so far. Glad it's all sorted out for you now. Back to imaging
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 06:32 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement