various script discussion (was Re: rawopint.lua: Fast, accurate intervalometer with raw exposure met - Script Writing - CHDK Forum

various script discussion (was Re: rawopint.lua: Fast, accurate intervalometer with raw exposure met

  • 10 Replies
  • 3135 Views
*

Offline Caefix

  • *****
  • 947
  • Sorry, busy deleting test shots...
Advertisements
maybe I'm mistaken and it is normal for an aps-c sensor, but the log i posted a while back had tsens of over 50C, the log from a few days back still had 45C. although iso was only 200.
The interval was 30 sec, so i can't imagine that is quick enough to heat it up that much.
FWIW, I wouldn't be surprised to see >50c in warm ambient conditions with a script like rawopint. (lack of surprise should not be taken as any judgement on whether it's healthy or not ;))

A user reported problems around 80c https://chdk.setepontos.com/index.php?topic=13501.0 with cameras in an enclosure.
:-* How to do shutdown / awake cam with lens kept extended?
All lifetime is a loan from eternity.

*

Offline c_joerg

  • *****
  • 1251
How to do shutdown / awake cam with lens kept extended?
1) On EOS M an interval Script with power down https://chdk.setepontos.com/index.php?topic=13956.0
2) Changing to playback mode between shoots with cancel retract timer
https://chdk.setepontos.com/index.php?topic=13737.0
3) Long exposure times and short time between shoots keeps senor temperature low.


@reyalp
Thanks, so I will try it…

M100 100a, M3 121a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

*

Offline Caefix

  • *****
  • 947
  • Sorry, busy deleting test shots...
Quote from: c_joerg link=topic=12697.msg145328#msg145328
3) Long exposure times and short time between shoots keeps senor temperature low.

[/quote
Nice, in tourist´s handheld scripts it might be some microtuning to loop something like
Code: [Select]
set_iso(temp)
todo()
shoot()
set_iso(1)
sleep(...
All lifetime is a loan from eternity.

*

Offline Caefix

  • *****
  • 947
  • Sorry, busy deleting test shots...
 :xmas Only tested on Ixus 265, all fine there.
Code: [Select]
--[[--
@title dimmer.lua
@chdk_version 1.4
--]]--

function dimmer(tim,dim)
dim=dim or 1
tim=tim or 0
local iso=get_iso_mode()
   set_iso_mode(dim)
   press("shoot_half")
   wait_click(tim) -- or md_detect...
   release("shoot_half")
   set_iso_mode(iso)
end

dimmer()

« Last Edit: 17 / March / 2021, 16:23:07 by Caefix »
All lifetime is a loan from eternity.


*

Offline reyalp

  • ******
  • 14121
I split this from the rawopint thread since it doesn't appear to be connected to that script.

I don't understand what the iso_mode manipulation is intended to accomplish.
Don't forget what the H stands for.

*

Offline c_joerg

  • *****
  • 1251
I don't understand what the iso_mode manipulation is intended to accomplish.

Neither do I…
Maybe a darkening of the display?
However, this cannot prevent the main temperature development of the sensor.
The problem is that the sensor is constantly being read. In order to reduce the temperature increase, the reading of the sensor had to be prevented during the breaks.
M100 100a, M3 121a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

*

Offline Caefix

  • *****
  • 947
  • Sorry, busy deleting test shots...
I don't understand what the iso_mode manipulation is intended to accomplish.

Neither do I…
Maybe a darkening of the display?
However, this cannot prevent the main temperature development of the sensor.
The problem is that the sensor is constantly being read. In order to reduce the temperature increase, the reading of the sensor had to be prevented during the breaks.
:) I agree.
I found "amplifier glow" & thought, that iso heats that amplifier, cooking sensor...
in some cases near asteroids belt.

All lifetime is a loan from eternity.

*

Offline reyalp

  • ******
  • 14121
:) I agree.
I found "amplifier glow" & thought, that iso heats that amplifier, cooking sensor...
I don't have hard data but IMHO, seeing amp glow more at high ISO has more to do with amplifying the stuff close to the noise floor than the amp working harder.

In any case, the ISO setting doesn't control the actual amplifier setting between shots. The camera juggles shutter speed and gain to provide an appropriate preview. See https://chdk.setepontos.com/index.php?topic=13508.msg145106#msg145106

If you wanted to make the camera read out less often in live view, you'd want it to use as long exposure as possible to force the frame rate down. This would suggest setting a high ISO setting in the UI, so the camera will need to make the preview brighter, which will (all else being equal) require longer exposure. No idea whether this has perceptible impact. I'd expect half press to run hotter than idling in live view, because it draws more power and the camera normally uses a higher frame rate and likely clocks some things faster.
Don't forget what the H stands for.


*

Offline Caefix

  • *****
  • 947
  • Sorry, busy deleting test shots...
I'd expect half press to run hotter than idling in live view, because it draws more power...
  ;)  _/\/\_/\__ Confirmed. wait_click(0) is now stable at 96°F, after half press it went up to 100 102.

BUT...
the camera normally uses a higher frame rate and likely clocks some things faster.
::) maybe could fastest md_detect reaction time be shortened if in shoot_half?
« Last Edit: 18 / March / 2021, 15:13:33 by Caefix »
All lifetime is a loan from eternity.

*

Offline c_joerg

  • *****
  • 1251
Some temperature measurements from me on M3.
Live View vs Longtime Exposure
M100 100a, M3 121a, G9x II (1.00c), 2*G1x (101a,100e), S110 (103a), SX50 (100c), SX230 (101a), S45,
Flickr https://www.flickr.com/photos/136329431@N06/albums
YouTube https://www.youtube.com/channel/UCrTH0tHy9OYTVDzWIvXEMlw/videos?shelf_id=0&view=0&sort=dd

 

SimplePortal 2.3.6 © 2008-2014, SimplePortal