"The problem is that you can't really perfectly match dark and light frames." Ahh but you can Jerry, have you forgotten the "long exposure noise reduction"...
8483
Jerry Lodriguss
lodrigj
May 1, 2010 3:55 pm
In-Camera long-exposure nose reduction is a very poor solution. It's not only losing clear darky-sky time for gathering photons to improve the s/n ratio... ...
8484
arbSaro
rpomillo
May 1, 2010 7:45 pm
Jerry, you guess right! CCD engineering data sheet report linearity figures, while CMOS data sheets simply are silent on this topic. As a consequence (for...
8485
Blair MacDonald
schmidtnewt
May 1, 2010 7:57 pm
Actually CMOS sensors are as linear as any other approach and inherently anti-blooming to boot. This comes Deon the random access scheme used to access each...
8486
Blair MacDonald
schmidtnewt
May 1, 2010 8:07 pm
I see my blackberry butchered my typing, Deon should be from! Blair MacDonald (from my Blackberry) ... From: "Blair MacDonald" <b.macdonald@...> ...
8487
juan_conejero
May 1, 2010 8:40 pm
FWIW, we have implemented an automatic dark frame scaling feature in our ImageCalibration tool, which we have released recently with PixInsight 1.6 under GPL...
8488
Jerry Lodriguss
lodrigj
May 2, 2010 2:46 am
Hi Rosario, I think it should be a fairly simple matter to measure some test shots to see if the CMOS is linear. Christian Buil said this about the Canon 40D: ...
8489
deus_ex_mamiya
May 2, 2010 10:33 am
Not only that, Blair, but I was intrigued to learn that CCDs operate via a "shirt register". I did a bit of research and discovered the following: - Lumberjack...
8490
arbSaro
rpomillo
May 2, 2010 11:28 am
Hi Jerry, very interesting :)) I can agree only if linearity requirement may be matter of compromise. In my opinion the signal at CMOS chip output is widely...
8491
Blair MacDonald
schmidtnewt
May 2, 2010 12:10 pm
Ah! Missed that one. You have to love those predictive typing systems on smart (?) phones. I always thought the Hawaiian shirt systems to be too loud and thus...
8492
Jerry Lodriguss
lodrigj
May 2, 2010 5:59 pm
Hi Rosario, You will get no argument from me that if serious science is your goal, then a scientific CCD is the equipment you should be using and not a DSLR. ...
8493
arbSaro
rpomillo
May 2, 2010 9:12 pm
Jerry, I have to delude you: I took the responsibility to infer my arguments, simply collecting a lot of minimal signs from various sources. Dalsa site is one...
8494
Blair MacDonald
schmidtnewt
May 2, 2010 10:10 pm
Rosario: You may have inferred a bit too much. Both CCD’s and CMOS systems have linearity specs around the one percent level. We tested several before ...
8495
Jerry Lodriguss
lodrigj
May 3, 2010 3:42 am
Hi Rosario, Thank you for the links. I will check them out. Jerry ... A Beginner's Guide to DSLR Astrophotography: http://www.astropix.com/BGDA/BGDA.HTM An...
8496
Jerry Lodriguss
lodrigj
May 3, 2010 3:45 am
Hi Blair, Thank you for those links, and for your comments on this subject. Jerry ... A Beginner's Guide to DSLR Astrophotography: ...
8497
Gg Mm
gmst83
May 3, 2010 9:04 am
Hi Luc, the problem is mainly when the image reduction ends and I'd like to use stretching and luminance corrections. Furthermore, using the notebook display,...
8498
marcello.amari@...
stellairama
May 3, 2010 9:45 am
[Non-text portions of this message have been removed]...
8499
Neil Heacock
luko_x
May 8, 2010 9:19 am
Hello Luc (et al), I know this has been discussed before, but I was wondering if we'll see some mild form of calibration in a future version of DSS Live? It...
8500
deepskystacker
May 8, 2010 2:09 pm
Hi Neil, It is in the todo list. It's not a problem with the engine (it is the same DSS is using) but more a way of finding the right user interface. Anyway, I...
8501
Neil Heacock
luko_x
May 8, 2010 6:20 pm
Yippee!! I was thinking simply a spot in the settings to choose a master dark, master flat (previously made of course). Luc, seriously, DSS Live is really...
8502
deepskystacker
May 8, 2010 6:35 pm
Hi Neil, Just so you know, you can zoom in and out using the mouse wheel... Clear skies, Luc...
8503
Neil Heacock
luko_x
May 8, 2010 8:40 pm
Doh! I had no idea. You continue to totally ROCK! -Neil On May 8, 2010, at 11:35 AM, "deepskystacker" <deepskystacker@...>...
8504
antonymorrish@...
antonymorris...
May 10, 2010 6:02 pm
Hi All newby here :-) can any one tell me the ideal settings for stacking raw files from a canon 450d, i've looked at the setting but the 450d isn't listed so...
8505
bernard boulant
bbboulant
May 10, 2010 6:45 pm
Hi Tony, It is not necessary if you use the RAW format of Canon (crw/cr2). This list is useful for FITS format only Regards -- Bernard Boulant ...
8506
shurik0001
May 13, 2010 7:48 pm
I uploaded 2 images into the photos section , Album name: "Dust halos", to illustrate the dust halo problem that I am stuck with: 1. m51 stretched image was...
8507
bernard boulant
bbboulant
May 13, 2010 11:00 pm
Hi, the focus has changed between light and flat. Regards 2010/5/13 shurik0001 <shurik0001@...> ... -- Bernard Boulant http://www.astrosurf.com/bboulant ...
8508
shurik0001
May 14, 2010 3:01 am
I am leaning towards the same conclusion based on other forums discussing my data. I am not sure how that happened..do you think if I refocus on the same...
8509
Sander Pool
sander_pool
May 14, 2010 4:09 am
Alex, if you can upload a single bias, light, dark and flat file it may be easier to debug. Focus change may cause this but it seems like a rather drastic...
8510
deus_ex_mamiya
May 14, 2010 11:32 am
Hi Alex, Notice how in the flattened M51, the dust shadow residuals are too dark on their lower left edges and too bright on their opposite, upper right edges?...
8511
Kevin
krutenb
May 16, 2010 1:44 pm
I've been battling this whole winter with a/guiding my EQ6 mount with little success. My setup is a C8 and SW ED80 Pro on ADM dual bar. My guider is a Meade...
