Lock-it Box Experiences?

[King Cheung]

I am using a Lockit ACL-203, but after a day shooting, it wasn't accurate. At the end of the first day, the camera ran 2 frames faster. At the end of the second day, the camera ran 2 seconds faster.
I think we don't set the Lockit correctly.
We are using SD702T. The Red camera setting is 4K/36 25fps.
Can anyone suggest us the appropriate Switch setting of Lockit, please
Thanks.

 

[Jonathan Smiles]

Have used the Ambient Lockit boxes many times (D9, Green Zone etc), without issue.

On Green Zone used for both TC and Tri-Level sync (just like 3D), no problems.

Tip - fresh batteries every day!

 

[King Cheung]

Have used the Ambient Lockit boxes many times (D9, Green Zone etc), without issue.

On Green Zone used for both TC and Tri-Level sync (just like 3D), no problems.

Tip - fresh batteries every day!

Thanks, Jonathan. Can you share with me about your setting? I have a feeling that I didn't set my switches correctly. Now, I switch to wordclock. Is it a problem.
Thanks in advance.

 

[J. Eric Camp]

Same thing, unfortunately. Why can a cheap EX3 keep TC after changing a battery? Besides, the RED needs to be shut down as often as possible, often enough in-between takes (!), because of overheating issues.
So, semantics aside, in practice, in the field, the TC implementation does not work. Thats why outside solutions like using a lockit box have to come into play - to fix it.

Karl, yes the RED tc could be better. That being said:

Aside from in extreme conditions (I'm talking when I was in the desert in egypt) I turn the camera on at call and don't turn it off till lunch.

If I turn a sb3 off and then right back on it has lost it's jam. This really isn't some big issue. Could it be improved, sure.

On point: I use sb-3's constantly. Small and does the job with out complaining. Never had an issue with them, and yes as Jonathan states, replace the batteries every morning and you will be wise.

 

[Mike Paul]

"At the end of the first day, the camera ran 2 frames faster"

It all depends on how you are implementing the use of Lockit's (or any other sync-box, for that matter).

If you have jammed the Lockit from your 702T in the morning, and then attached it to the Red, but you never re-jammed throughout the day - then sure, you're going to see some drift.

While the clocks in the 702T and the Ambient are both governed by highly accurate temperature compensated crystal oscillators to produce a .01ppm tolerance, you have to remember that once they are disconnected from each other, they are running on their own clocks and drift (however small) is inevitable. Dropping (or drifting, I should say) by a half-frame to a frame over the course of eight hours is the norm, so the fact that you are seeing a 2-frame offset at the end of the day seems "in the ballpark" to me.

If you re-jam everything, say, every four to five hours, the offset at the end of the day will be greatly minimized. If you had you Lockit set incorrectly, the drift would have been much, much larger (think several seconds vs. several frames).

For reference, Peter Gray's website has a wealth of information about Lockit settings for camera (scroll to #31 for 25P/RED).
http://www.petergray.org/lockits.html

Oh, and while fresh batteries in the morning should be a Law, it has no effect on the accuracy of the clock. The clock will not slow down as the batteries drain, but it will stop completely if they are dead

MP

 

[Harry Clark]

Listen to Eric Camp and Mike Paul.
They are both spot on.
Cheers,
Harry

 

[Jake Bastian]

Same thing, unfortunately. Why can a cheap EX3 keep TC after changing a battery? Besides, the RED needs to be shut down as often as possible, often enough in-between takes (!), because of overheating issues.
So, semantics aside, in practice, in the field, the TC implementation does not work. Thats why outside solutions like using a lockit box have to come into play - to fix it.

You shouldn't be shutting your camera down when it's running hot, that's why it has a fan. It will cool down much faster/more efficiently if you leave it running. Sounds like you're wasting a lot of time on set unnecessarily. I agree with you on the timecode implementation though - it's always seemed a bit wonky to me.