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Messages - gonzzalo_b

#1
Quote from: Levas on September 16, 2020, 10:22:23 AM
With that card I would expect higher speeds possible. I have a 128GB Sandisk 170mb card and it does around ~80Mb/s with the 240Mhz option setting.

But at what resolution setting are you recording, you might be in a video mode that is not data heavy. Normal 1824x1026 video mode doesn't need more speed then ~60Mb/s. So could be that your card can handle more, but your resolution setting doesn't require more speed.

Hello, I'm new in this forum and I like to share my test using the last build magiclantern-Nightly.2020Jul16.6D116 with the SanDisk SDXC Extreme Pro 64 GB 95Mb/s recommended. I hope this can be helpful.
I named the settings for practical purposes

Settings A (240Mhz)
SD: Sandisk Extreme pro 64gb 95mb/s
RES: 1824x1024
AR: 16:9
Frame rate:24 fps ALL-I
Data format: 14 bit (uncompressed)
SD OVERCLOCK: 240 Mhz
CONTINUOUS RECORDING
With this overclock when is selected RAW VIDEO shows me this before playback
74.8Mb/s 73x3.1MB, 23.970/982p Expect 2417-10000 frames at 78.8Mb/s

Using this configuration I can continuously record with no problem at any light situation but after I playback the videos something weird happen. If I try to record again suddenly stops recording after a few seconds, then I go back and see the settings and show me this:
74.8Mb/s 73x3.1MB, 23.970/982p Expect 322-505 frames at 62.9Mb/s
until I restart the camera it solves the problem. But when I use the SD OVERLOCK at 192 Mhz this happen...

Settings B (192Mhz)
SD: Sandisk Extreme pro 64gb 95mb/s
RES: 1824x1024
AR: 16:9
Frame rate:24 fps ALL-I
Data format: 14 bit (uncompressed)
SD OVERCLOCK: 192 Mhz

I can playback and record without any problem but it is no longer continuously record. It's about 1 min 10 sec of recording.

Other test results with different bit rate and Overclock
SD: Sandisk Extreme pro 64gb 95mb/s
RES: 1824x1024
AR: 16:9
Frame rate:24 fps ALL-I
Data format: 12 bit | 10 bit (uncompressed)
SD overclock: 192 Mhz | 240 Mhz

Even if I restar the camera after changing every setting, I can't playback the videos with 12 bit uncompressed and 10 bit uncompressed, only black frames are played, but when I transfer to the computer I can see it and edit. I will not use it because for me it is important to preview the video and be sure it is ok. With the 14 bit, 14 bit lossess, 12 bit lossess and 11-8 bit lossess there is no problem with the playback.

In conclusion

SETTINGS A (240Mhz)
-I can record continuously at any Bit rate, but when I playback the videos I can't no longer record and I have to restart the camera to solved it.
-This configuration gives me more image quality.
-12 bit and 10 bit (UNCOMPRESSED CAN'T PLAYBACK)

SETTINGS B (192Mhz)
-Playback and record with no problems but less recording time depending of the bit rate used.
-This configuration gives me less image quality, a little of aliasing.
-12 bit and 10 bit (UNCOMPRESSED CAN'T PLAYBACK)

Notes:
-In the SETTING A (240Mhz) after playback, when I record and automatically stops recording the flushing buffer remains a longer time. (Maybe the problem is after the playback can't reset the memory and for that reason can only record a few frames.)
-In playback mode, when I select the videos with compression (14 ,12, 11-8) appear the same info. It shows "14 bpp LJ92" in each video with different bit rate.
-When I change the SD OVERCLOCK and restart the camera, do not update the frames that it can capture until start the first recording, after that it showns the real frames can be recorded. (Maybe this module have problems updating)
-I also use another SD card Lexar Professional SD 633x 128GB SDXC UHS-I 95Mb/s but the performance is inferior compare to the sandisk.

I will use the SETTINGS A (240Mhz) for a while and let you know for the results. And hope could be a fix whit recording after the playback in the future.

Thank you Levas for helping us with your hard work.