IISAC11 timelapse part B day to night transition

[Bassnut]

Hi Guys

A different technic (http://fredsastro.smugmug.com/Timelapse/Timelapse-video/16566156_JZtdwb#1558887775_2qqqvDD) . From the Imaging feild in day time to dark night sky, captured in Jpeg with full auto exposure.

The 1st effort was CR2 small. I think capturing in raw and converting to jpeg is better than capture in jpeg.

5 D mk2, 24mm 1.4L, 12 sec period, but auto else. 30fps . My Timelapse machine control.

[bmitchell82]

I remember you calling fellas that would do wide fields wusses. :D now you have really pushed the wide field wus boundarys :D Still very nice both parts A and B :D

[Omaroo]

Again, excellent Fred. Interesting to note that there was a jump in luminosity just a little after dark. If you look at mine, it occurred at the same rough time. I guess that it had a lot to do with leaving the two 5D-IIs in full auto.

I'm still gobsmacked over that lens. The wider field worked better too, and I should have left mine also at 24mm.

[Bassnut]

Thanks Brendan but sigh, theres WFW and theres proper uber WF timelapse OK, thems are not the same and different at the same time.

[Bassnut]

Yes, I noticed that jump too, thought I had switched to manual exposure, but not obviously if you had it too.

Its a puzzle, but I suspect the internal metering gets tricky at low light and a bit of guessing sets in. Phil and I (mostly Phil) have developed an external ultra wide range ambient light meter for full day/night measuring to allow full auto control, it wont be causeing that kind of nasty Canon jumpiness ;).

[naskies]

Perhaps it's a quirk with the 5D2's meter? That "jump" looks a lot like the ones I get on my 5D2 if I stop my intervalometer (Canon TC-80N3) mid-shoot when the light levels drop at sunset. For example, the metered EV will be gradually dropping as the sun goes down, I press the start/stop button on the intervalometer, and the next frame is suddenly metered at (random guess) 1 stop brighter than the previous frame... and then continue to drop normally from that value.



Sounds interesting! I've been thinking of hooking up my 5D2 to the laptop and writing scripts to handle more complex exposure settings... e.g. starting with ISO 100, f/8, EC 0 in Av mode during the sunny afternoon, and then gradually raise the ISO to keep shutter speeds manageable, while very slowly dropping the exposure compensation to mimic the "getting dark" feeling.

[jjjnettie]

yeah yeah yeah, you keep telling yerself that. :lol:

beaut time lapse anyway you see it.

[Octane]

Your poor, poor shutter! :)

Nicely done.

H

[Bassnut]

We analysed that for full day/night transitions, we needed to vary all of apature, ISO and exposure time. You would need to vary apature too.

[Bassnut]

Thanks H. Yes, for 30fps luxury, the frames for the weekend were in the 1000s. Still, thats what the Canon is for, it will willingly suffer for art :D.

[bmitchell82]

Im with JJJ Fred, Ignorance is bliss Denial is nirvana! WFW it up big boy :D

[DavidTrap]

If the 150000 actuations of the 5D isn't enought, the 1D-X should sort them out (400000 actuations).

DT

[Bassnut]

Actually, I wonder what it costs for a new 5d shutter?

Mm, 1hr of 30fps video is 100000 actuations, it's worth considering.

[DavidTrap]

I don't think the mechanical shutter is used for video - isn't it an electronic shutter???

DT

[Bassnut]

yes, for RAW images its mechanical. "video" is the pokey HD video mode.

Geez, time lapse is not video, its proper images (in this case long exposure) as a sequence strung together into a video in post, whole different ball game.