×
INDI Library v1.8.5 Released (19 Apr 2020)

April 2020 release of INDI Library v1.8.5 introduces new drivers while providing fixes and improvements to existing devices and core framework.

canon: can't set frame size

1 year 9 months ago 1 year 9 months ago by alacant.
alacant
Platinum Boarder
Platinum Boarder
Posts: 482
More
Topic Author
canon: can't set frame size #28819
Hi everyone
I set the Canon frame size to 5208x3476 but as soon as I open the capture module, it sets it to 5184x3456. Even if I edit the esq file with 5208x3476, I still get the lover values...
1. What is the correct setting and how do I make it stick?
2. Can I take CR2 frames in camera (e.g. flats) and then convert them to the fits I get fro kstars?
Thanks

ubuntu 18.04
700d, eq6, t7m
The topic has been locked.
1 year 9 months ago
wvreeven
Platinum Boarder
Platinum Boarder
Posts: 1475
Karma: 7
More
canon: can't set frame size #28821
The full chip size is indeed 5208x3476 but some of the pixels are not used for imaging. The true FOV is 5184x3456 pixels. Have a look at the Aspect Ratio and Specifications sections of the manual of your Canon DSLR camera (at least, that's where it is specified in case of my Canon EOS 700D == Canon Rebel T5i camera) . There the used frame sizes are specified.

By the way, I guess that the overhead pixels are used as a buffer during read out of the chip but I am not 100% sure.

ASI1600MM-Pro Cooled and filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R
The topic has been locked.
1 year 9 months ago
wvreeven
Platinum Boarder
Platinum Boarder
Posts: 1475
Karma: 7
More
canon: can't set frame size #28822
As for question 2) for image processing it is much better to make sure that all frames (i.e. Light, Dark, Flat and Bias) are in the same format. Ekos can record FITS and Native where Native will result in CR2 files in case of a Canon camera. It is possible to specify which you prefer in the CCD options panel. Don't forget to save the options after you make a change or else they will not stick.

ASI1600MM-Pro Cooled and filter wheel with a SkyWatcher Esprit 80 ED on a SkyWatcher HEQ5-Pro
ASI1600MM-Pro Cooled and filter wheel with an 8" TS Ritchey-Chrétien on a SkyWatcher EQ6-R
The topic has been locked.
1 year 9 months ago 1 year 9 months ago by Herrhausen.
Herrhausen
Platinum Boarder
Platinum Boarder
Posts: 634
Karma: 3
More
canon: can't set frame size #28825
Re 2) I had the very same wish a while back when I had taken CR2 flats and was unable to have them converted correctly.

http://indilib.org/forum/general/3323-question-re-fits-cr2-conversion.html

The hack that Copello suggested did work perfectly for me. Taking CR2 flats would be convenient to me since I could do it without having the cam connected to the computer/Ekos. Instead I resorted to not taking any flats at all.
The topic has been locked.
1 year 9 months ago
Copello
Senior Boarder
Senior Boarder
Posts: 63
Karma: 1
More
canon: can't set frame size #28826
Hi there,

by taking a quick look inside the code:
// cdesc contains counter-clock wise e.g. RGBG CFA pattern while we want it sequential as RGGB
    bayer_pattern[0] = RawProcessor.imgdata.idata.cdesc[0];
    bayer_pattern[1] = RawProcessor.imgdata.idata.cdesc[1];
    bayer_pattern[2] = RawProcessor.imgdata.idata.cdesc[3];
    bayer_pattern[3] = RawProcessor.imgdata.idata.cdesc[2];
    bayer_pattern[4] = '\0';

    int first_visible_pixel = RawProcessor.imgdata.rawdata.sizes.raw_width * RawProcessor.imgdata.sizes.top_margin + RawProcessor.imgdata.sizes.left_margin;

One can see that the actual image size is smaller (the first visible pixel does not start at 0), but many pixel later.
There is a nice explanation in the LibRaw forum why that happens: In summary

"Many cameras, including Canons, contains 'masked pixels' around visible area.
Yes, in Canon data these pixels used for black level calibration.
On other cameras (e.g. Nikons) these pixels may be used for banding noise elimination."


So some portion of pixels are masked out, thus the actual size is slightly smaller.
The topic has been locked.
1 year 5 months ago 1 year 5 months ago by Herrhausen.
Herrhausen
Platinum Boarder
Platinum Boarder
Posts: 634
Karma: 3
More
canon: can't set frame size #33166
obsolete
The topic has been locked.
1 year 5 months ago 1 year 5 months ago by Herrhausen.
Herrhausen
Platinum Boarder
Platinum Boarder
Posts: 634
Karma: 3
More
canon: can't set frame size #33167
obsolete
The topic has been locked.
1 year 5 months ago
Herrhausen
Platinum Boarder
Platinum Boarder
Posts: 634
Karma: 3
More
canon: can't set frame size #33168
Booh, sorry these two messages were meant to go to the "Conversion ti fits from CR2 changes geometry?" thread.
The topic has been locked.
1 year 5 months ago
knro
Administrator
Administrator
Posts: 8000
Karma: 51
canon: can't set frame size #33197
Closing this to avoid confusion.

Jasem Mutlaq
Support INDI & Ekos; Get StellarMate Astrophotography Gadget.
How to Submit Logs when you have problems?
Add your observatory info
The topic has been locked.
Time to create page: 0.542 seconds