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UPDATE FROM MABULA

I have had a very rough 2 months unfortunately health wise. I was struck 3x in a row with bacterial infections. The second infection occurred  after a routine hospital checkup and I became very sick. I had to rest and take a lot of antibiotics. Once I was recovering and restarting work 1 month ago, I again became sick. The infection was not yet gone, so even more antibiotics and rest was needed. Needless to say, it took a lot of my energy and I needed a lot of rest.

 

Finally, the infection is really gone and my energy is coming back step-by-step now and I have started work again. I am terribly sorry to have kept you waiting for support. I will address all outstanding questions and e-mails step-by step and will be on the forum daily from today.

 

APP 2.0.0-beta47 will come soon as well, a lot of work was already completed before I became very ill, so the release is also nearly ready for you. Beta47 will be much faster actually. Many workflows will be more than 2x faster, mosaics can even be 10x faster than before because registration really received a major boost... all compared to beta46.  Before I release it, I will make sure that everything is working properly and then I will release it.

Question about calibration frame orientation

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(@tbar23)
Main Sequence Star
Joined: 5 years ago
Posts: 20
Topic starter  

I have a few questions about calibration frames and camera orientation. I am learning how to use a new-to-me HEQ5 Pro mount with SynScan. Tonight I did a meridian flip partway through my imaging session. I did not change camera orientation - as I suspect is common (I’m using an OSC).

Does this orientation change have any impact on my calibration frames?

My typical work flow is to finish my lights, put lens cap on telescope, shoot a number of darks while I start breaking down my setup. Obviously, this also changes camera orientation. Does this matter?

Once I’m all broken down, I’ll stop taking darks and usually bring my camera+telescope inside. Sometimes I will take flats and dark flats soon thereafter, but if the outside-inside temps are very different, I’ll wait a while (or next day).

Again, I’m assuming orientation doesn’t matter as long as optical train and focus stays the same.

Final calibration question: I understand that flats require the optical train / focus to remain the same, but I can re-use darks if I change telescopes as long as the OSC, ISO, temp and exposure are all the same, yes?

Furthermore, I can re-use flats and dark flats from a different day as long as the optical train / focus is the same, correct?

Just making sure I understand calibration frame basics.

Thank you!

 

-Trevor



   
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(@wvreeven)
Quasar
Joined: 8 years ago
Posts: 2134
 
Posted by: @tbar23

Does this orientation change have any impact on my calibration frames?

The orientation of the camera doesn't change w.r.t. the telescope, so no, this will not affect the flats.

Posted by: @tbar23

My typical work flow is to finish my lights, put lens cap on telescope, shoot a number of darks while I start breaking down my setup. Obviously, this also changes camera orientation. Does this matter?

There is no light involved with taking darks, so this doesn't change the orientation.

Posted by: @tbar23

Again, I’m assuming orientation doesn’t matter as long as optical train and focus stays the same.

That assumption is correct.

Posted by: @tbar23

I understand that flats require the optical train / focus to remain the same, but I can re-use darks if I change telescopes as long as the OSC, ISO, temp and exposure are all the same, yes?

Yes, the darks only depend on the camera and nothing else.

Posted by: @tbar23

I can re-use flats and dark flats from a different day as long as the optical train / focus is the same, correct?

Darks yes. Flats depend on the orientation of the camera w.r.t. the telescope and also on dust motes. If no dust is visible and the orientation of the camera doesn't change w.r.t. the telescope then you can reuse the flats. In general, however, it is recommended to take new flats everytime the camera and telescope are disconnected.

About the image orientation in general: what camera are you using? It seems to be a non-cooled camera. If it is a DSLR then please make sure that auto-rotation of the images is switched off in the camera. Otherwise the camera itself will modify the meta-data of the image which APP should deal properly with but better safe than sorry.



   
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(@tbar23)
Main Sequence Star
Joined: 5 years ago
Posts: 20
Topic starter  
Posted by: @wvreeven

About the image orientation in general: what camera are you using? It seems to be a non-cooled camera. If it is a DSLR then please make sure that auto-rotation of the images is switched off in the camera. Otherwise the camera itself will modify the meta-data of the image which APP should deal properly with but better safe than sorry.

Ah - definitely worth checking, thank you. I’m using a Canon EOS RP mirrorless.

Your response also has me re-thinking my use of the word “orientation”. I was thinking about how the camera+telescope is oriented with respect to the ground (e.g. what direction is it pointing, landscape vs portrait, etc.) I now understand that orientation means the orientation of the camera with respect to the telescope. That helps. Thank you.



   
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