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INDI Library v2.0.6 is Released (02 Feb 2024)

Bi-monthly release with minor bug fixes and improvements

Alignment/Plate solve problems

What is:

1. CCD Resolution as reported by INDI
2. CCD Resolution of the actual image
3. Pixel size in INDI
4. Reference pixel size for your camera? is it square pixel?
5. Focal length (1000?)
9 years 5 days ago #3716

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I have a Canon 1100D with APS-C 22.2 × 14.7 mm (4,272 × 2,848 pixels) This gives px=5,31 py= 5.11

I have used 5.18 for both px and py and pixel size in ekos/INDI

INDI report via dcraw image size 4290 x 2856:

2015-03-25T07:11:16: Driver indi_gphoto_ccd: dcraw -c -t 0 -4 -D /tmp/indi_lWdSPSStarting exposure
2015-03-25T07:11:16: Driver indi_gphoto_ccd: Mutex locked
2015-03-25T07:11:16: Driver indi_gphoto_ccd: Using exposure time: 1
2015-03-25T07:11:16: Driver indi_gphoto_ccd: Exposure started
2015-03-25T07:11:17: Driver indi_gphoto_ccd: Reading exposure
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Exposure complete
2015-03-25T07:11:20: Driver indi_gphoto_ccd: You need to specify a folder starting with /store_xxxxxxxxx/
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Retval: 0
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Downloading //capt0002.cr2
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Retval: 0
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Deleting.
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Retval: 0
2015-03-25T07:11:20: Driver indi_gphoto_ccd: dcraw -i -t 0 -v /tmp/indi_aqSzQR 2> /dev/null
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Filename: /tmp/indi_aqSzQR
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Timestamp: Wed Mar 25 09:17:09 2015
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Camera: Canon EOS 1100D
2015-03-25T07:11:20: Driver indi_gphoto_ccd: ISO speed: 800
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Shutter: 1.0 sec
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Aperture: f/inf
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Focal length: 50.0 mm
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Embedded ICC profile: no
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Number of raw images: 1
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Thumb size: 4272 x 2848
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Full size: 4352 x 2874
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Image size: 4290 x 2856
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Output size: 4290 x 2856
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Raw colors: 3
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Filter pattern: RGGBRGGBRGGBRGGB
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Daylight multipliers: 2.353782 0.931874 1.178846
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Camera multipliers: 957.000000 1024.000000 1097.000000 1024.000000
2015-03-25T07:11:20: Driver indi_gphoto_ccd: Reading exposure 4290 x 2856

I have a SW 200P with focal length 1000 mm, and using a SW comacorector with no reduction on focal length.

The CCD resolution is reported by solve-field to be "pixel scale 1.17086 arcsec/pix." I don't know where to find the CCD resolution reported by INDI?
9 years 4 days ago #3726

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If we're using 4,272 for Width, to get 83.63 minutes FOV with a 1000 focal length, your pixel size must be 5.695

The formula is:

FOV = 206264.8062470963552/60.0 * CCD_WIDTH * CCD_PIXEL_WIDTH / 1000.0 / FOCAL_LENGTH

Since you're getting 83 minutes in the solver, one of the variables above is not correct. The CCD Width (4290 vs 4272) doesn't make a difference, so it comes down to problems in focal length and/or pixel size.
The following user(s) said Thank You: Steen
9 years 4 days ago #3727

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I guess that my coma corector does have som reduction i focal length. I will test whenever the weather gets better. I'm pretty sure that my pix size is between 5.11 and 5.32 from whatever I can read from the web.

Anyway I have a solution now on how to get the right FOV for my equipment by running solve-field on the command line as shown in previus reply.

Thanks again for being very helpfull here at the forum and for all the effort you put into this nice software!
9 years 3 days ago #3728

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Last night I got into similar issue - astrometry solver reported that I have different focus length. I was imaging with C14 (3910 mm) and ATIK 383L+ (3362x2504@5.4x5.4um). Most of the time it reported that I have around 2087 mm, once it was around 4162 mm. Does binning has any influence on this?

P.S. One more question - will it harm if I install ALL the astrometry deb packages?
Last edit: 8 years 11 months ago by Alexandru Barbovschi.
8 years 11 months ago #3980

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Good catch, I just made it account for binning. And there is no harm in installing all the packages AFAIK.
8 years 11 months ago #3982

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Glad to be helpful ;) One more problem. If solver is taking too much I press stop. But I still receive messages that solver is working and if I try too solve again it fails, reporting some problem with parity (don't remember exact message). Have to wait till no more messages arrives... Annoying and lose of time. Can you make stop more brutal? :D (for info - I am talking about online solver, I didn't test offline yet)
8 years 11 months ago #3985

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