Author Topic: Filming lightning  (Read 6566 times)

dorjeerand

  • Newbie
  • *
  • Posts: 5
    • View Profile
Filming lightning
« on: February 11, 2023, 01:27:44 AM »
Hi Everyone,

I've got a challenge here that could do with some help. I'm trying to film lightning at night. So far, every attempt has failed. Not because the lightning was too fast for the lightning sensor, but because my Chronos 2.1 couldn't accept the underexposed image.

I'm shooting 1920 at 1000fps. Black calibration all done. Because lightning brightens up the whole scene, I had to start with a heavily underexposed image. When the lightning came on, I could see the lightning streaks. However the image was filled with vertical and horizontal banding artefacts due to the initial underexposure. Is there any way to shoot a relatively clean image of lightning activities? Thanks for the help!

CavOkay

  • Newbie
  • *
  • Posts: 12
    • View Profile
Re: Filming lightning
« Reply #1 on: February 11, 2023, 04:01:10 AM »
Hello,

This is also one of my Main activity / passion with the Chronos, yes I found this is pretty challenging to have quality shootings with the amount of light that a strike can provide, same kind of challenge happen with DSLR :

 either you open too much the aperture / Hi ISO, and you get maybe some details of fainter ramifications and more distant lightnings, with rain curtains on the way, or the image and strike gets totally burned and overexposed.
Closing too much can decrease the image crispness, can help on very bright lightnings with multiple strikes, but conversely can underexpose the fainter details, tiny lightning branches.

With the Chronos it will be the same, and you need to use a wise trade-off, of not closing too much (will generate noise like you described) and not opening too much either.

actually there wont be any rule of thumb, it would depend on many factors, the actual lighning brightness, depending on the strike distance, depending as well on dimming sources like clouds, rain or hail curtains ....

IMHO, what could help to relieve from noise in these low light followed by sudden high light with the Chronos,  would be to choose a low analog an digital gain or keep it standard but not push it high.
the higher the gain, the higher the noise, alas, and i should say the Chronos is not yet fully optimized to cope with noise as efficiently as DSLR do

So you need to choose wisely your aperture depending on the average lightness amount you observe at a given moment,
and you must accept misses, and overburned or underexposed images are parts of the game :)

Hopefully, new coming firmwares will improve Chronos denoising, this is my hope,
and set apart the Chronos hardware / software actual limiting factors, getting trained is a key point to have successul captures.

good luck with your Lighnings chase !

Here in France we must wait couple months at least from now to have a chance to get some.

 

Solscud007

  • Jr. Member
  • **
  • Posts: 84
    • View Profile
Re: Filming lightning
« Reply #2 on: February 11, 2023, 07:49:05 PM »
How are you timing the filming with the lightning strike? Especially since lightning is not predictable in its location? Are you recording constantly and hoping the buffer caught the strike?

weatherproductions

  • Newbie
  • *
  • Posts: 16
    • View Profile
Re: Filming lightning
« Reply #3 on: February 13, 2023, 10:28:18 AM »
Use Black cal often, get as much light as possible, short parts will always be overexposured, but thats no problem in the final video.

https://youtu.be/wDW7_fdYxFU?t=99

https://youtu.be/-QfxMO2p8DM?t=2

https://youtu.be/VeWnJ9flLyo?t=34

The lines that occur on some images can also be removed in post.

regards,
Christoph



dorjeerand

  • Newbie
  • *
  • Posts: 5
    • View Profile
Re: Filming lightning
« Reply #4 on: February 16, 2023, 01:29:43 AM »
Thanks for your tips! Have fun and all the best!

Hello,

This is also one of my Main activity / passion with the Chronos, yes I found this is pretty challenging to have quality shootings with the amount of light that a strike can provide, same kind of challenge happen with DSLR :

 either you open too much the aperture / Hi ISO, and you get maybe some details of fainter ramifications and more distant lightnings, with rain curtains on the way, or the image and strike gets totally burned and overexposed.
Closing too much can decrease the image crispness, can help on very bright lightnings with multiple strikes, but conversely can underexpose the fainter details, tiny lightning branches.

With the Chronos it will be the same, and you need to use a wise trade-off, of not closing too much (will generate noise like you described) and not opening too much either.

actually there wont be any rule of thumb, it would depend on many factors, the actual lighning brightness, depending on the strike distance, depending as well on dimming sources like clouds, rain or hail curtains ....

IMHO, what could help to relieve from noise in these low light followed by sudden high light with the Chronos,  would be to choose a low analog an digital gain or keep it standard but not push it high.
the higher the gain, the higher the noise, alas, and i should say the Chronos is not yet fully optimized to cope with noise as efficiently as DSLR do

So you need to choose wisely your aperture depending on the average lightness amount you observe at a given moment,
and you must accept misses, and overburned or underexposed images are parts of the game :)

Hopefully, new coming firmwares will improve Chronos denoising, this is my hope,
and set apart the Chronos hardware / software actual limiting factors, getting trained is a key point to have successul captures.

good luck with your Lighnings chase !

Here in France we must wait couple months at least from now to have a chance to get some.

dorjeerand

  • Newbie
  • *
  • Posts: 5
    • View Profile
Re: Filming lightning
« Reply #5 on: February 16, 2023, 01:33:12 AM »
Hi, I use MIOPS lightning sensor to time the lightning (https://www.miops.com/). I set to record around 2sec before trigger and the remaining 9sec after trigger. Have to manage the sensitivity of the lightning sensor. It's easier at night as I can dial down the sensitivity. But more tricky during daytime.

How are you timing the filming with the lightning strike? Especially since lightning is not predictable in its location? Are you recording constantly and hoping the buffer caught the strike?

dorjeerand

  • Newbie
  • *
  • Posts: 5
    • View Profile
Re: Filming lightning
« Reply #6 on: February 16, 2023, 01:34:17 AM »
Thanks for sharing! Any advices/tips on post editing?

Use Black cal often, get as much light as possible, short parts will always be overexposured, but thats no problem in the final video.

https://youtu.be/wDW7_fdYxFU?t=99

https://youtu.be/-QfxMO2p8DM?t=2

https://youtu.be/VeWnJ9flLyo?t=34

The lines that occur on some images can also be removed in post.

regards,
Christoph

1022mm

  • Newbie
  • *
  • Posts: 48
    • View Profile
Re: Filming lightning
« Reply #7 on: April 06, 2023, 04:28:40 AM »
I do a lot of filming of lightning with the Chronos 1.4.   Keep in mind that what you are trying to capture with high speed cameras is the *leaders*, which are very dim relative to the very bright return stroke. The leader propagation is the interesting part of a lightning flash to capture in high speed, so you would expose for them rather than the bright return stroke.  This means the return stroke will almost always overexpose, but it's no big deal as it's not the part of the event that has much you can resolve at the Chronos' framerates.

Again, lightning leaders are faintly luminous and do not show up well on the Chronos unless they are relatively close (within 2 or 3 miles) or they are the brighter ones associated with a high peak current flash.   The fastest lens you can afford at its most wide-open aperture helps.   I am using an F2.8 wide angle lens, and I can capture most leaders within 3 miles distance.

weatherproductions

  • Newbie
  • *
  • Posts: 16
    • View Profile
Re: Filming lightning
« Reply #8 on: April 12, 2023, 09:11:27 AM »
I am using gamma 2.6, and for the lines you should play a bit with the noise reduction