700D Doesn't seem to be writing correctly?

[Quelian]

I have successfully installed ML on my 700D however after trying to capture raw footage (at 16:9, 720p) as well as (2.35:1, 1504x640) which should be able to record continuous with no problem my camera shuts off with skipped frames after about 15 seconds or so. My SD card is a Lexar Professional 1000x 64GB SDXC UHS-II Card which from the SD card specification should be able to handle 60mb/s minimum write so i am really confused what is going on! any help is appreciated!!!

[masc]

720p = ~50fps? Then you're at ~50MB/s ( = 1504*640*50 ). Is there a SD_UHS overclocking module for the 700D? If I am right, the card slot is limited to 40MB/s without overclocking (theoretically, practically less).

[theBilalFakhouri]

Standard 700D write speed is 40MB/S , in High FPS mods it drops to 36MB/S , Using sd_uhs it's about ~53MB/S but also in High FPS it drops to 40MB/S depending on frame rate.

In all cameras also 5D3 III and in High FPS the speed drops from ~85MB/s to 67MB/S  something like that, there is a bottleneck in High FPS mods it's normal , for more performance disable global draw use 10-bit lossless and lower the resolution a bit for longer recording times.

[Quelian]

Just 24fps actually, that's why i am so confused as to why it cant handle it

[Walter Schulz]

Benchmark in cam:
Modules tab -> Bench.mo ON -> Restart -> Debug tab -> Benchmarks -> Card Benchmarks -> Quick R/W benchmark (1 min)
and/or use a cardreader *without* UHS-II interface.

If benchmark is ok it is most likely you misconfigured your cam trying to use MLV_lite and MLV_rec at the same time ...

[Quelian]

I ran the benchmark as requested, this is the result:

ML Nightly.2018Jul103.700D115, 7a3b5fa3f4c6 (unified) tip
Mode: MV-1000 LCD, Global Draw: OFF

Write speed (buffer=16384k): 37.4mb/s
Read speed (buffer=16384k): 37.1mb/s
Write speed (buffer=16384k): 33.6mb/s
Read speed (buffer=16384k): 37.1mb/s

Definitely not using MLV_Lite and MLV_Rec at the same time, only modules manually enabled right now are MLV_Rec and MLV_Play

[Walter Schulz]

May I ask for converting Bench0.PPM (found in card's root) to JPEG or PNG, uploading it somewhere with public access and link it here? At least one error ...
Sure about second write rate number? 33,6?

[Quelian]

Read it wrong on the camera second one is actually 33.8 not 33.6

[Walter Schulz]

Looks like this card is loosing around 10 percent of its write rate if heated up. That's unfortunate! Some other cards benefit from heat or drop by a far lesser amount.
Adjust write rate to lower margin for continuous recording or get another type.

[Quelian]

From my understanding the sd card should be specified to 60mb/s minimum according to the sd card specifications, i get that the 700d is bottlenecking that down to around 40mb/s but then shouldn't that mean it would be able to easily handle that 40mb/s? I'm just confused as to why it is dipping down so low seeming as everyone else recommends this aspect ratio + resolution combo as continuous on the 700d and i cant seem to get 15 seconds out of it?

[Walter Schulz]

but then shouldn't that mean it would be able to easily handle that 40mb/s?

No, it depends on the card and its interaction with cams SD-card interface.

[Quelian]

Dang that sucks, bought this SD card because i thought i would be able to have a bit of overhead, do you know which SD cards mesh well with the 700d to allow continuous speeds at 720p 24fps?

[Walter Schulz]

No guarantee for 700D (don't own one and can't verify) but currently Sandisk Extreme Pro 95 MByte/s (not 150 or more) is undisputed to be the best performer you can get for ML cams with SD-card interface.

[Quelian]

Thank you for the recommendation! I'l be returning this lexar card and getting a sandisk, shame ill have to downgrade from 64 to 32gb but if its got the speed needed then it'l have to be done.

[Walter Schulz]

You can use experimental build with 14 bit lossless compression (about 55 percent compression, depending on scene) or 12 bit recording, instead.

Just recorded 500 seconds with lenscap mounted in 720p24 and 14 bit (uncompressed). File size 19380718080 Bytes -> 36.97 MiByte/s to Sandisk Extreme Pro 95 MB/s (128 GB capacity) and EOS 100D/SL1.