WARNING to all PAL users: SD timecode error at DVinfo.net

John Mitchell · October 14th, 2005, 03:54 AM

I decided to post this under a new thread from my original as I have now managed to clarify with JVC Australia exactly what is going on with the timecode in PAL SD mode and I wanted to warn PAL users.

FAULT: 25fps timecode is recognised as drop frame by Avid when GY-HD100/101 is in 50i mode over RS422 and also exhibits digitise problems over firewire. eg enter a timecode of 01:00:00:00 and the timecode actually is recognised as 01;00;00;00 on RS 422 (the Avid will not digitise at all when this is the case); over firewire it drops in an unasked drop frame outpoint (this difference I put down to the different way Avid reads the 422 and firewire protocols) - it will digitise but will also drop out randomly.

BACKGROUND:
In firmware version 1.12 there was a setting in the advanced menu of all the 100/101's in the VTR section called "Drop frame mask". This setting was set to ON in the factory. Don't bother looking for it - it's buried in the service menu. When asked why they would have a drop frame mask for PAL no one at JVC had a logical explanation. Our best guess is this may even be a universal setting for the camera in interlaced mode.

This morning JVC's chief engineer called by my work after I made them aware of the original fault, to change that setting on my camera (now firmware 1.17) to see if was the culprit. Unfortunately JVC have removed that option from the menu in Firmware revision 1.14 and 1.17. He returned later in the day with a version 1.12 firmware camera. We did two records - one with the setting on and one off. End result - that setting is definitely the culprit. To the best of my knowledge this setting only affects SD PAL but it could apply to other frame rates - I can't test because at this stage Avid only supports 30/60 in HD and 50i in SD. The other thing to bear in mind is that some decks/programs might not check the timecode stream as carefully as the DSR1500AP/Avid combination.

It seems every PAL camera has been sent out this way - my recommendation: only use PAL SD mode if you are prepared to digitise without code: once the recorded code is bad there is no way of fixing it. Now that JVC Japan has been made aware of the problem it should be a fairly simple matter of revised firmware that will allow a fix.

John Mitchell · October 19th, 2005, 08:49 AM

It wasn't missing from the firmware, but the camera had to be in 50i mode for the option to be available.

My camera hasnow been fixed.

Strangely the option drop frame mask had to be set to ON.

I think it's some JVC firmware designers idea of a joke...

Guy Barwood · October 20th, 2005, 02:22 AM

so a new firmware is not needed? just enabling this firmware option?

John Mitchell · October 20th, 2005, 06:59 AM

Quote:

Originally Posted by Guy Barwood

so a new firmware is not needed? just enabling this firmware option?

That's correct Guy and I'd suggest every PAL user get it done. It's a five minute job for service.

October 14th, 2005, 03:54 AM	#1
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	WARNING to all PAL users: SD timecode error I decided to post this under a new thread from my original as I have now managed to clarify with JVC Australia exactly what is going on with the timecode in PAL SD mode and I wanted to warn PAL users. FAULT: 25fps timecode is recognised as drop frame by Avid when GY-HD100/101 is in 50i mode over RS422 and also exhibits digitise problems over firewire. eg enter a timecode of 01:00:00:00 and the timecode actually is recognised as 01;00;00;00 on RS 422 (the Avid will not digitise at all when this is the case); over firewire it drops in an unasked drop frame outpoint (this difference I put down to the different way Avid reads the 422 and firewire protocols) - it will digitise but will also drop out randomly. BACKGROUND: In firmware version 1.12 there was a setting in the advanced menu of all the 100/101's in the VTR section called "Drop frame mask". This setting was set to ON in the factory. Don't bother looking for it - it's buried in the service menu. When asked why they would have a drop frame mask for PAL no one at JVC had a logical explanation. Our best guess is this may even be a universal setting for the camera in interlaced mode. This morning JVC's chief engineer called by my work after I made them aware of the original fault, to change that setting on my camera (now firmware 1.17) to see if was the culprit. Unfortunately JVC have removed that option from the menu in Firmware revision 1.14 and 1.17. He returned later in the day with a version 1.12 firmware camera. We did two records - one with the setting on and one off. End result - that setting is definitely the culprit. To the best of my knowledge this setting only affects SD PAL but it could apply to other frame rates - I can't test because at this stage Avid only supports 30/60 in HD and 50i in SD. The other thing to bear in mind is that some decks/programs might not check the timecode stream as carefully as the DSR1500AP/Avid combination. It seems every PAL camera has been sent out this way - my recommendation: only use PAL SD mode if you are prepared to digitise without code: once the recorded code is bad there is no way of fixing it. Now that JVC Japan has been made aware of the problem it should be a fairly simple matter of revised firmware that will allow a fix.

October 19th, 2005, 08:49 AM	#2
John Mitchell Contributor Join Date: Jul 2005 Location: Sydney Australia Posts: 873	Update It wasn't missing from the firmware, but the camera had to be in 50i mode for the option to be available. My camera hasnow been fixed. Strangely the option drop frame mask had to be set to ON. I think it's some JVC firmware designers idea of a joke...

October 20th, 2005, 02:22 AM	#3
Guy Barwood Major Player Join Date: Mar 2005 Posts: 423	so a new firmware is not needed? just enabling this firmware option?