Possibility of 4k/50p? at DVinfo.net

Philip Lewis · November 27th, 2016, 12:01 PM

Just wondered if there was any likelihood of a firmware update to allow 50 fps capture with JVC 4K camcorders? Despite rigorous self discipline in pans etc at 25p I still do not like the 4K footage "jitters" seen on camera movements.

Philip Lewis · December 5th, 2016, 06:45 AM

Starting to feel like the invisible man on this forum, however I think I've discovered that reducing the shutter speed from 1/50 to 1/40 second at 25p 4K has significantly improved the smoothness of footage no doubt due to frame motion blur increasing.
I'm going to do some more tests at even lower shutter speeds. Whilst I'm here, regarding gain settings, if I preset the Gain L switch to "AGC" (rather than "off") does AGC only kick in when the max aperture of the lens has been reached? I'm assuming so - and IF so is there any disadvantages to leaving gain on auto? Thanks.

Duncan Craig · December 5th, 2016, 06:59 AM

Hi Philip! 180 degree shutter is the norm for me.

I'm used to shooting with progressive scan, so I guess I tend to pan at speeds that look right while I'm doing them.

Regarding your gain question, it's up to you to try it and tell us!! Again personally I don't use auto gain. But sometimes I'll use auto white or maybe focus if the situation demands it.

Philip Lewis · December 5th, 2016, 07:30 AM

Hi Duncan, thanks for coming back. I was hoping video AGC only kicked in at maximum aperture but that doesn't seem to be the case. I did a test at F4 with indoor daylight where I didn't really need to increase gain normally. There were with lots of dark and shadowy areas as well as some parts lit directly by daylight. The image was much brighter in the darker parts with AGC on (which may not necessarily be better). So much for manual exposure with AGC active as it seems to be kicking in at any aperture if it "thinks" the scene is underexposed, however it must be quite subtle as gross underexposure remains, well, underexposed. I'm not entirely sure, therefore, what is going on.
Regarding the shutter speed question with progressive footage, when following the 180 rule ie 4K/25p/1/50 second some recent footage showed even slow pans taking several seconds were a bit jittery and some white water close-ups I filmed looked most unrealistic and that with a stationary camera.
I may be over sensitive to all this as my missus sees nothing wrong with the footage. I took some shots of cars travelling at 30 mph across the frame hand-held today at 1/40 and it all looked a lot more realistic.

Noa Put · December 5th, 2016, 09:43 AM

Quote:

Originally Posted by Philip Lewis

Just wondered if there was any likelihood of a firmware update to allow 50 fps capture with JVC 4K camcorders?

Jvc is going to release a firmware update soon with 4K50p but not internally on the sd card but externally to a recorder, see also this thread: http://www.dvinfo.net/forum/jvc-4k-p...016-ls300.html

Quote:

does AGC only kick in when the max aperture of the lens has been reached? I'm assuming so - and IF so is there any disadvantages to leaving gain on auto?

ACG means the camera takes a average reading of what it sees in a frame and adjusts the gain to that, you can have some control on changing the camera's judgment over gain by changing the ae level. The only other control over AGC is that you can set a max gain level that the camera may be not pass.

My personal opinion is that this is not a camera to use AGC, you basically let the camera decide what the gain should be risking over or underexposure, gain or just your exposure in general is something you should always set manually for best results.

Philip Lewis · December 5th, 2016, 11:15 AM

Thank you for the responses....now could someone explain to me what audio "SW Set" is? as opposed to "Full Auto" (posted in another thread but no response so far)

Noa Put · December 5th, 2016, 01:08 PM

I don't know what the words "sw" stand for but it basically means that when you have the switch on the side of the camera to either preset of full you can decide in the camera menu for each setting separately if you want the camera to handle the audio gain automatically (full auto) and then a little "a" appears on the left side of you audiometers or that you want to have manual control (swset)

Duncan Craig · December 6th, 2016, 02:27 AM

I guess SW is 'Switch'. So if the audio gain switches are set to manual, then it will keep them that way...
I think Philip is using something other than the LS300, but I suppose the information is still correct?

Philip Lewis · December 7th, 2016, 02:03 AM

Thanks for the replies, I'm using the GY-HM170.

November 27th, 2016, 12:01 PM	#1
Philip Lewis Regular Crew Join Date: Jan 2016 Location: Barrow in Furness UK Posts: 30	Possibility of 4k/50p? Just wondered if there was any likelihood of a firmware update to allow 50 fps capture with JVC 4K camcorders? Despite rigorous self discipline in pans etc at 25p I still do not like the 4K footage "jitters" seen on camera movements.

December 5th, 2016, 06:45 AM	#2
Philip Lewis Regular Crew Join Date: Jan 2016 Location: Barrow in Furness UK Posts: 30	Re: Possibility of 4k/50p? Starting to feel like the invisible man on this forum, however I think I've discovered that reducing the shutter speed from 1/50 to 1/40 second at 25p 4K has significantly improved the smoothness of footage no doubt due to frame motion blur increasing. I'm going to do some more tests at even lower shutter speeds. Whilst I'm here, regarding gain settings, if I preset the Gain L switch to "AGC" (rather than "off") does AGC only kick in when the max aperture of the lens has been reached? I'm assuming so - and IF so is there any disadvantages to leaving gain on auto? Thanks.

December 5th, 2016, 06:59 AM	#3
Duncan Craig Major Player Join Date: Jul 2003 Location: Leeds, UK Posts: 660 Images: 10	Re: Possibility of 4k/50p? Hi Philip! 180 degree shutter is the norm for me. I'm used to shooting with progressive scan, so I guess I tend to pan at speeds that look right while I'm doing them. Regarding your gain question, it's up to you to try it and tell us!! Again personally I don't use auto gain. But sometimes I'll use auto white or maybe focus if the situation demands it. __________________ FCPX/LS300/EX1/FS100/GoPro/Vinten/HotHead/Jib/Track/Dedos/Lightstorm/Coollights

December 5th, 2016, 07:30 AM	#4
Philip Lewis Regular Crew Join Date: Jan 2016 Location: Barrow in Furness UK Posts: 30	Re: Possibility of 4k/50p? Hi Duncan, thanks for coming back. I was hoping video AGC only kicked in at maximum aperture but that doesn't seem to be the case. I did a test at F4 with indoor daylight where I didn't really need to increase gain normally. There were with lots of dark and shadowy areas as well as some parts lit directly by daylight. The image was much brighter in the darker parts with AGC on (which may not necessarily be better). So much for manual exposure with AGC active as it seems to be kicking in at any aperture if it "thinks" the scene is underexposed, however it must be quite subtle as gross underexposure remains, well, underexposed. I'm not entirely sure, therefore, what is going on. Regarding the shutter speed question with progressive footage, when following the 180 rule ie 4K/25p/1/50 second some recent footage showed even slow pans taking several seconds were a bit jittery and some white water close-ups I filmed looked most unrealistic and that with a stationary camera. I may be over sensitive to all this as my missus sees nothing wrong with the footage. I took some shots of cars travelling at 30 mph across the frame hand-held today at 1/40 and it all looked a lot more realistic.

December 5th, 2016, 11:15 AM	#6
Philip Lewis Regular Crew Join Date: Jan 2016 Location: Barrow in Furness UK Posts: 30	Re: Possibility of 4k/50p? Thank you for the responses....now could someone explain to me what audio "SW Set" is? as opposed to "Full Auto" (posted in another thread but no response so far)

December 5th, 2016, 01:08 PM	#7
Noa Put Inner Circle Join Date: Jun 2007 Location: Belgium Posts: 9,509	Re: Possibility of 4k/50p? I don't know what the words "sw" stand for but it basically means that when you have the switch on the side of the camera to either preset of full you can decide in the camera menu for each setting separately if you want the camera to handle the audio gain automatically (full auto) and then a little "a" appears on the left side of you audiometers or that you want to have manual control (swset)

December 6th, 2016, 02:27 AM	#8
Duncan Craig Major Player Join Date: Jul 2003 Location: Leeds, UK Posts: 660 Images: 10	Re: Possibility of 4k/50p? I guess SW is 'Switch'. So if the audio gain switches are set to manual, then it will keep them that way... I think Philip is using something other than the LS300, but I suppose the information is still correct? __________________ FCPX/LS300/EX1/FS100/GoPro/Vinten/HotHead/Jib/Track/Dedos/Lightstorm/Coollights

December 7th, 2016, 02:03 AM	#9
Philip Lewis Regular Crew Join Date: Jan 2016 Location: Barrow in Furness UK Posts: 30	Re: Possibility of 4k/50p? Thanks for the replies, I'm using the GY-HM170.