Cold Temp Blackshade Calibration

[Andrew Spirk]

I was recently on a very cold outdoor shoot and our Helium Weapon simply would not black shade calibrate.

Here was the process:

Outdoor temps were around 22F, and we were in the middle of a cold lake with windchill probably around 15F. Either way, it was freezing.

After letting the Helium heat up, the max temp the sensor showed was 19C, and after running on record for a bit, it managed to get up to 23C.

I did a manual calibration for 24fps @ 180 degrees. It captured etc, but once it hit analyze it only got to 1/3 through before it stopped for a good few seconds, then the screen shut off and camera was unresponsive. The sidekick monitor was still on, as was the camera. After waiting a solid 20 minutes I shut off the camera manually by holding down the side button and booted back up. I was greeted with an improper shutdown prompt, and no new calibration profile.

I then tried another manual calibration, same result. Then finally tried an auto, same result.

The T and E were both in the red, and unfortunately I could not get in touch with Red in time (early morning EST shoot) to diagnose further and we ended up having to shoot with both T/E in the red. The footage thankfully turned out fine, but you can tell there is some loss of range in the shadow capture.

I was a bit shocked the camera had so many issues calibrating considering how many times I've used DSMC bodies in the cold without any issue whatsoever. This is my first DSMC2 body along with a new Helium sensor (acquired about 2 months ago).

Any experience with this kind of issue?

 

[Jose Espinosa]

Hello!

I get that all the time over here with the Helium sensor, it never goes near the right temp in the cold. It's also a bit surprising since my Epic Dragon was easily able to, and while in my experience shooting with a cold camera doesn't produce alarming or unusable results, it is indeed subpar in the shadows, specially when compared directly to optimal shooting conditions. My workaround has been:

-I calibrate the camera to 40c indoors before the shoot.
-I have two custom pieces of warm but breatheable fabric that *could* cover completely both the air intake and outake. I gaffer tape them to *partially* cover both vents.
-Then, I set it to manual fan settings and to the lowest (20). I do this because for some reason "Adaptative mode" hasn't been smart enough and it always spins the fans faster than manual mode even when the camera is super cold.
-I partially obstruct the air flow depending on how easy or hard it is for the camera to be around 40. Normally I start from covering both vents to half. It's usually not difficult to find the right amount, and once found it doesn't require too much attention. I guess the camera could be in adaptive mode too and it should manage the temperature, but then you should also keep an eye that the fans are not overworking, ie. if you have restricted the airflow too much.

*I calibrate to 40c because that's the average temp that has been the easiest for my camera to keep while using the method above and without having to be too active in the managing and also while being quite easy to find the sweet spot.
*If it's not as cold, just partially covering the air *outtake* will do.

I hope this is useful for you and of course I would be happier if I wouldn't have to do any of this, but at least there is something you can do. Greetings from Finland!

 

[Thai Christen]

I shoot Helium in cold and super cold weather a lot and have no issue or whatsoever.
Best is to have different calibration settings for different temperature condition. I usually have three at fan temp 43, 37, 30.

Example, for supercold (minus Celsius), I set fan to adaptive 30. Then I put my camera into a freezer (which is usually set to minus 20 Degree Celsius), leave it there for about 10 minutes. Then manual calibrate and leave camera in the freezer until it is done. Thats it. So when you have to shoot in cold or supercold, you just switch to the appropriate calibration settings. No magic.

 

[steve green]

I've had a couple of cold weather shoots this month. I just black shade indoors at room temp, when on the shoot in the cold (5-25F), I tape off the exhaust vents and put the fan in "quiet mode". That keeps the "T" in the green all day. Works great!

 

[Audy Erel]

:gun: "DO NOT OBSTRUCT!"

 

[Joshua VP]

@audy Erel, are you referring to not obstructing the Fan? In Jakarta, you shouldn't have any issues in that moist subtropic jungle. Up here in the cold, we have to obstruct to keep the camera going..

 

[Stuart Graham]

I've had a couple of cold weather shoots this month. I just black shade indoors at room temp, when on the shoot in the cold (5-25F), I tape off the exhaust vents and put the fan in "quiet mode". That keeps the "T" in the green all day. Works great!

I do the same, tape exhaust & also tape the intake up too, not 100% but more than 50% & then monitor the temp & fan speeds.

I also AUTO CAL the sensor the night or day before the shoot, 55 mins is a v long time when on set IMO.

I had a -18c shoot in China & we kept two HELIUM's at 44degree's for 3 days without a hitch...wish I could've said the same for the batteries we used the chemical hand warmers wrapped around them but they were old cells & lasted about 30 mins each despite being 'warm'.

If you do 'tape up' exhaust & fan just make sure you monitor the fan & temperature settings during long takes & or in transit between locations. Use Fluorescent tape & not black so there's a nice visual reminder that you've blocked up the camera from breathing / cooling .

Hope this helps, Stu.

 

[Joshua VP]

Also Note: in extreme colds, I put my camera in a Rain bag, and tape 2 hand warmers to the monitor(i've had my monitor go down in the cold and never come back to life) and the side of the camera inside the bag. As well as taping up the vents about 50% and turning the fans to "Adaptive Mode." I also, try not to power the camera down during the shoot in the cold - which ends up forcing me to utilize 6 batteries for a 8 hr shoot in the cold - on my Dragon, I've had issues powering up in the extreme cold, so I usually power on inside or in a warmer area, then leave it on.

I also, had a super hard time calibrating with a battery and ended up giving up on trying which was a total bummer. I think on shoots in extreme colds, you need to bring DC power and then leave the camera outside the night before the shoot to get a correct calibration. Because my Red Bricks wouldn't power all the way through the calibration in the cold..