using NTC in the timelapse screen

qDslrDashbord error reports
wolfgangh
Posts: 7
Joined: 11 Feb 2019, 17:48

using NTC in the timelapse screen

Post by wolfgangh »

I am using NTC in the lrtimelapse screen. As I learned in a tutorial of Gunther a NTC of two will bring down the reference value during dusk to the half of the initial value ( I had a value of 132 using only a Region of the whole picture. I switched the NTC to 3.0 and started the Holy grail (sunset) with NTC. The new night reference value was then 88. After my calculation it should be a third of 132, that means 44 but NTC only subtracted 44. Am I wrong with my calculation? What can I do to bring the reference value much further down?
hubaiz
Site Admin
Posts: 2001
Joined: 27 Jan 2015, 18:58

Re: using NTC in the timelapse screen

Post by hubaiz »

What was the NTC text saying?
wolfgangh
Posts: 7
Joined: 11 Feb 2019, 17:48

Re: using NTC in the timelapse screen

Post by wolfgangh »

What do you mean? on the 'button' is shown NTC 3.0
hubaiz
Site Admin
Posts: 2001
Joined: 27 Jan 2015, 18:58

Re: using NTC in the timelapse screen

Post by hubaiz »

In the information LRTimelapse display (upper left corner of the image) there is a 'NTC:' line.
wolfgangh
Posts: 7
Joined: 11 Feb 2019, 17:48

Re: using NTC in the timelapse screen

Post by wolfgangh »

At first (I started the program an hour befor sunset) it showed the correct sunset time for my location, then it showed dusk an the end of dusk and finally it showed Night and -> 6.27 what means our actual time where the sun will be about 12 degrees under horizon tomorrow morning,the begin of the nautical twilight
hubaiz
Site Admin
Posts: 2001
Joined: 27 Jan 2015, 18:58

Re: using NTC in the timelapse screen

Post by hubaiz »

at night it will be your ref value - ref value / ntc value (3.0 in your case) + delta value if any.
you can use a smaller number, like 1.5
wolfgangh
Posts: 7
Joined: 11 Feb 2019, 17:48

Re: using NTC in the timelapse screen

Post by wolfgangh »

That is what I thought, but it has not been the reference value /NTC Value, it has only been the reference value /1.5 even though I set the NTC to 3.0
wolfgangh
Posts: 7
Joined: 11 Feb 2019, 17:48

Re: using NTC in the timelapse screen

Post by wolfgangh »

I did just another test today with NTC 5.0 . I send some screenshots to visualize
Attachments
Bild3.jpg
Bild3.jpg (195.7 KiB) Viewed 6437 times
Bild2.jpg
Bild2.jpg (193.92 KiB) Viewed 6437 times
Bild1.jpg
Bild1.jpg (186.58 KiB) Viewed 6437 times
hubaiz
Site Admin
Posts: 2001
Joined: 27 Jan 2015, 18:58

Re: using NTC in the timelapse screen

Post by hubaiz »

In case of a higher NTC value (3,0 or 5,0 you used) the NTC reference will be closer to the original reference.
To have a smaller NTC reference you need to use a smaller NTC value like 1,5
wolfgangh
Posts: 7
Joined: 11 Feb 2019, 17:48

Re: using NTC in the timelapse screen

Post by wolfgangh »

Thanks, will try it this evening.
May you tell me how the mathematical relation between the reference value and the NTC to calculate the night reference value is?
kind regards wolfgang
Post Reply