cal :T/E... what to do if it turns yellow...

[Denis Buhot]

Hi all. I know that the Epic is pretty touchy about actual recording parameters, as compared to calibration parameters. So, in the event of a minor change, i.e. cal: T/E changing to yellow in the course of a shooting, what should I do ? Adjust the fan speed ? Perform calibration again, then loosing recorded datas ? Do I have to pay attention to the "-" or the "+" ? Or is any change likely to affect the result (noise, for instance ?). Help much appreciated.

 

[Stephen Williams]

If you do your black shading at normal running temperate with a 1/100 exposure time, it will be very rare not to always be green once the camera is warmed up.
Adjust fan settings so it returns to green.

 

[Marcello Altieri]

Black shading at temperature and shutter speed

 

[Elsie N]

Hi all. I know that the Epic is pretty touchy about actual recording parameters, as compared to calibration parameters. So, in the event of a minor change, i.e. cal: T/E changing to yellow in the course of a shooting, what should I do ? Adjust the fan speed ? Perform calibration again, then loosing recorded datas ? Do I have to pay attention to the "-" or the "+" ? Or is any change likely to affect the result (noise, for instance ?). Help much appreciated.

Hah! Denis, I'm guessing you are the same as me when it comes to reading operating manuals.

Operating manuals are boring... no story.

But I've found if I allow the camera to warm up to it's required temp the yellow goes away. If you are on the latest beta version... 5.1.23, as per Mark L. Pederson from Offhollywood's remarks it seems Adaptive Preview Quiet Record mode allows you to set the temp you want your camera to run at and this allows the camera to rather quickly reach that setting by keeping fans off.

I've set mine at 60 degrees and after a few hours of letting it idle it is holding to that temp with very little fan noise. I believe Trent from RED said the camera performs at it's optimal when operating at around 60 to 65 degrees. Sorta like a diesel engine I guess... hotter is sometimes better.

 

[Elsie N]

Hah! Denis, I'm guessing you are the same as me when it comes to reading operating manuals.

Operating manuals are boring... no story.

But I've found if I allow the camera to warm up to it's required temp the yellow goes away. If you are on the latest beta version... 5.1.23, as per Mark L. Pederson from Offhollywood's remarks it seems Adaptive Preview Quiet Record mode allows you to set the temp you want your camera to run at and this allows the camera to rather quickly reach that setting by keeping fans off.

I've set mine at 60 degrees and after a few hours of letting it idle it is holding to that temp with very little fan noise. I believe Trent from RED said the camera performs at it's optimal when operating at around 60 to 65 degrees. Sorta like a diesel engine I guess... hotter is sometimes better.

UPDATE: After allowing the camera to sit for roughly 8 hours and monitoring the temp during that time, the Adaptive mode worked perfectly. Then tried shooting 5% of a 128 GB SSD and noticed the yellow cal +T that Denis referred to. I then did a calibration at the 60 degree temperature and again shot a 5% of 128 SSD. All green and the Adaptive Preview Quiet Record mode seemed to work well. During the shooting period, the temp did rise to 67 degrees, but after stopping record, the fan came on a short time later and gradually brought the temp down to 60 degrees again. This happened about the same when shooting before and after calibration. During calibration, the temp stayed at 60 degrees.

ADDITIONAL: Just finished shooting a 25% duration and noticed the yellow Cal+T showed up somewhere around the 5% mark, which was also somewhere around 67 degrees. I watched as the temp climbed to 72 degrees before seemingly leveling off and only a faint sound from the fan. When I turned record off, the camera was silent for a few seconds and then raised the fan speed to something above 50 percent, I estimate, before gradually tapering down to a level required as maintenance for the 60 degree target.

I was shooting as a test with the camera's body cap on so was only shooting black. I'm guessing the sensor will labor more to record actual images and will possibly run hotter.

This raises questions... should one set the target higher for calibration and then reset to a preferred lower target temp for shooting, knowing the camera temp is going to rise during shooting? And the next question is, how high will the temperature rise before shutting the camera down.

 

[Denis Buhot]

Thanks to all ! Elsie...

Thanks to all ! Elsie...

... special thanks for your detailed answer. Yes, I couldn't find out in the operating manual Your final questions deserve an answer as well, from Red. I guess!

 

[Elsie N]

... special thanks for your detailed answer. Yes, I couldn't find out in the operating manual Your final questions deserve an answer as well, from Red. I guess!

Your welcome Denis... hope that helped.

 

[Nikhil Kamkolkar]

This raises questions... should one set the target higher for calibration and then reset to a preferred lower target temp for shooting, knowing the camera temp is going to rise during shooting? And the next question is, how high will the temperature rise before shutting the camera down.

Hi all - any thoughts on Elsie's questions?

 

[Sam Goldwater]

I was shooting as a test with the camera's body cap on so was only shooting black. I'm guessing the sensor will labor more to record actual images and will possibly run hotter.

I'd be very surprised if the sensor/processor discriminates its input in that way - surely whether recording the back of a lens cap or a dense forest canopy the computational load is the same, no?

 

[Terry VerHaar]

Elsie may have a point in that the compression algorithms will be working harder with complex images than with just black. Harder load on the ASICs.

 

[Mike P.]

The sensor likely wouldn't get hotter, but the processor/compression might. I think that's one of those variables that would have such a small affect (if at all) that it isn't worth worrying about.

As for the 'calibrate at 5c higher to compensate for record temps'; I think you'd be better off just using "Adaptive" rather than "Adaptive Preview, Quiet Record"... That way it will always maintain the desired core temp.

OH, that reminds me -- the ideal SENSOR temp might be 60-65c, but that would mean the core would have to be at like 80c (since I've noticed the sensor usually runs 10-15c cooler than the core), which isn't possible since the fans kick-in full-auto at 75c.

 

[Kevin Marshall]

It's not just the workload possibly being larger during record. It's in the name of the fan algorithm you're using - "Adaptive Preview Quiet Record."

If you set to simply "Adaptive," the camera works to maintain a constant temperature. With Quiet Record, the camera will lower the fan speed during record, and not go over the user-specified maximum. The fans will work less during record, and so the camera will heat up more, especially for longer takes. For shorter takes, it can be useful to get that last extra bit of fan noise gone, but longer takes can throw the temp more out of spec. This is kind of why I'm waffling between these two modes - each have their pluses and minuses.

 

[Mark L. Pederson]

It's not just the workload possibly being larger during record. It's in the name of the fan algorithm you're using - "Adaptive Preview Quiet Record."

If you set to simply "Adaptive," the camera works to maintain a constant temperature. With Quiet Record, the camera will lower the fan speed during record, and not go over the user-specified maximum. The fans will work less during record, and so the camera will heat up more, especially for longer takes. For shorter takes, it can be useful to get that last extra bit of fan noise gone, but longer takes can throw the temp more out of spec. This is kind of why I'm waffling between these two modes - each have their pluses and minuses.

Actually - both "Adaptive and Adaptive Quiet Record" work to get keep your camera to your target core temp.

"Adaptive" allows the camera to go to 75% fan speed while recording and 75% fan speed while in standby.

"Adaptive Quiet Record" just allows you to lower the fan speed while recording down to 25% if you desire. (If you set this to 75% - you are functioning the same as "Adaptive")

ADAPTIVE is, IMO, the best "go to" FAN SETTING - and go to ADAPTIVE QUEIT RECORD if you are in a situation shooting on "Adaptive" when you need even lower fan settings during record. 75%-80% of most real-world situations you are more than fine with Adaptive.

The secret is adjusting your target temp

 

[Nick Morrison]

The secret is adjusting your target temp

What temp is your secret sauce again? I forget.

 

[Mark L. Pederson]

What temp is your secret sauce again? I forget.

all depends on how much you are rolling and ambient temp.

The "secret" is just knowing that when you sensor starts to heat up enough to turn your CAL T/E yellow - you can, most of time, just adjust your target temp to 5 degrees cooler for example - and get it back to green without a new black shade. Same thing works the other way - if your sensor is running a too cool - just increase your target temp.

I like 68/70 on Dragon if it's rolling a ton on warm soundstage.