Search found 53 matches

by Dunmunro
12 Jun 2019, 22:04
Forum: General
Topic: AStroart 7 photometry & Astrometry question
Replies: 8
Views: 99

Re: AStroart 7 photometry & Astrometry question

Thanks to all who have responded - much appreciated. Einari, evidently had a bad GSCdata base. Cleaned computer reloaded Astroart 5.0 which I own and problem of no stars goes away. Fabedev. have not gotten that kind of error. Still trying to figure how to load some of the other data bases you have ...
by Dunmunro
24 May 2019, 00:17
Forum: General
Topic: New user - issues
Replies: 2
Views: 72

Re: New user - issues

1) There are sliders along the right hand side of the Main window to adjust the brightness and contrast. You can also place the mouse cursor over the image and right click the mouse and then select: Viewrange->auto->auto. 2) it is asking for arc seconds per pixel. There are various calculators onlin...
by Dunmunro
15 May 2019, 00:58
Forum: Image processing and analysis
Topic: FITS file doubles in size after preprocessing
Replies: 11
Views: 184

Re: FITS file doubles in size after preprocessing

Hi Dunmunro, I am using "Sigma+Sum". It seems that AA7 converts 16 bit fits files to 32 bit whenever it makes changes to the image, such as demosaicing and/or stacking. I haven't really considered this but it is probably necessary to preserve the data in the resulting files. It happens with my 16bi...
by Dunmunro
14 May 2019, 06:49
Forum: Image processing and analysis
Topic: FITS file doubles in size after preprocessing
Replies: 11
Views: 184

Re: FITS file doubles in size after preprocessing

I just got a ZWO ASI 1600 MM Cool this weekend, and I tested it last night. As expected, the 4656x3520 pixel images takes up approximately 32 MB disk space, the camera is 12 bpp => 2 bytes. However, after stacking, the resulting fits file is 64 MB ! The fits header for a single light, says "BITPIX ...
by Dunmunro
07 May 2019, 20:11
Forum: General
Topic: Astroart 7 Service Pack 1
Replies: 4
Views: 298

Re: Astroart 7 Service Pack 1

Thanks.
by Dunmunro
08 Apr 2019, 21:27
Forum: Image processing and analysis
Topic: How to make a part of the image look negative within the same image
Replies: 6
Views: 110

Re: How to make a part of the image look negative within the same image

Hi all !! I am a new user of Astroart 7 and I have a doubt because I want to select a part of an image to enlarge it and put it in negative in the initial image (to highlight that part) but I can not see it in negative. I copy a selection of the initial image, I paste it as a new image and then I e...
by Dunmunro
08 Apr 2019, 21:01
Forum: Image processing and analysis
Topic: Plate-solve-goto-center just perfect !
Replies: 9
Views: 293

Re: Plate-solve-goto-center just perfect !

I was using C8 @ 1390mm, SXV-694 Pixel size: 4.54uM x 4.54uM Field size 30.9 x 24.7 arcmin 0.674 arcsec/pixel. Don't know what guiding camera has to do with this but it's a ASI120mm and 50mm finder. Strange thing is like I wrote first Find coordinates worked then tried Plate solve center, it moved ...
by Dunmunro
08 Apr 2019, 19:03
Forum: Image processing and analysis
Topic: Plate-solve-goto-center just perfect !
Replies: 9
Views: 293

Re: Plate-solve-goto-center just perfect !

Back to this topic now that I have used AA's plate solving more. Mixed feelings about it. It doesn't always center object using plate solve (even if it has found coordinates). And in my last session I first used Find coordinates, then plate solve center, not center, then again Find coordinates and ...
by Dunmunro
02 Apr 2019, 08:56
Forum: Image processing and analysis
Topic: Image statistics, Min/Max values
Replies: 4
Views: 128

Re: Image statistics, Min/Max values

what exposure time are you using?

Does the ADU reach 4096 during terrestrial photography?

This article may be of some use:

http://www.stark-labs.com/craig/article ... earity.pdf
by Dunmunro
01 Apr 2019, 16:35
Forum: Image processing and analysis
Topic: Image statistics, Min/Max values
Replies: 4
Views: 128

Re: Image statistics, Min/Max values

Is the Image statistics Min/Max values ADU values? How does AstroArt calculate the values? For my Canon 1000D (12-bit) Max values never reaches the expected 2^12-1=4095 but is always arround 3500 to 3600. What is the min and background values? IIRC, Canon adds an offset which then reduces the ADU r...