can't understand things

[fillman86]

Okay, once I understand what this all means, then I'll decide if I want this.

I was looking at the chart http://www.magiclantern.fm/forum/index.php?topic=6215.0 and I want to know what they mean by crop and no crop? is it similar to apsc being 1.6? (though that wouldn't make sense.... wouldn't it still be the same amount of pixels?)

The other thing I don't understand is the numbers for buffer size.... I'm more lost than..... something that is really lost.....

Is there a chart for approximate recording times before it starts to frame skip? Are the columns with "continuous rec" the only modes that continuously record with out frame skipping because the buffer is full?

What are the advantages of ExFat over the other types?

I have a 600d but might upgrade too. Can you also save space in recording by not having an audio track? (I have a zoom etc for audio)

(please excuse bad grammar and english, I've been looking at this for a while and it's now almost 1:30am....)

[maxotics]

This may help, applies to all APS-C cameras.  For RAW video:

http://www.magiclantern.fm/forum/index.php?topic=8825.msg82948#msg82948

Crop essentially means taking a rectangular shape of pixels from the sensor that, when "blown up" effectively increases the focal length. 

Don't worry about the buffer size, etc., just read the posts and see what frame-rates/resolutions people are able to get with their camera/card/setup cofigurations.

ExFat just allows over 2gig file sizes.  Doesn't work on some cameras.  If it does, you want it.

Are you talking about RAW or H.264.  RAW doesn't record audio. 

[SpcCb]

(...)
ExFat just allows over 2gig file sizes.
(...)

Actually Fat32 is up to 4GB for a single file.
But it's not really a problem because you can record without stop in multiple files of 4GB.

[Midphase]

.... I'm more lost than..... something that is really lost.....

Sorry to be blunt, but you might want to move along. Seriously, not trying to be rude, but ML is not for everybody, and if some of these basic concepts are confusing you, you might not be the best type of user for this particular hack. In addition, on a 600D, you won't see particularly spectacular improvements so you might go through a whole lot of stuff for nothing.

You might consider checking out the Blackmagic Pocket Cinema Camera as an inexpensive raw solution for your video needs, and just use the 600D as a stills and casual shooting camera.

[ItsMeLenny]

Is there a chart for approximate recording times before it starts to frame skip? Are the columns with "continuous rec" the only modes that continuously record with out frame skipping because the buffer is full?

Also, when you're setting your desired frame size / resolution, it will tell you how many MB/s it will use, and if it will max out, down the bottom of the screen.

[fillman86]

I know buffer size isn't important to understand (thanks for the link though), I just like to know what I'm dealing with when I look at things. But if you don't know, it's fine.

I understand the idea of crop, but it's still dealing with the same amount of pixels, why would "max resolution in crop mode" be higher than "max resolution 1:1 liveview no crop"? Is there something I'm missing, or does the crop mode not use live view, thus freeing more processor?

[ItsMeLenny]

I know buffer size isn't important to understand (thanks for the link though), I just like to know what I'm dealing with when I look at things. But if you don't know, it's fine.

I understand the idea of crop, but it's still dealing with the same amount of pixels, why would "max resolution in crop mode" be higher than "max resolution 1:1 liveview no crop"? Is there something I'm missing, or does the crop mode not use live view, thus freeing more processor?

I don't know about others, but I can really not tell what you are asking.
You will have to reword it.

[Walter Schulz]

I understand (I suppose).
When RAW video was introduced there was much noise about the pixel limitation. The technical description given explains that ML grabs the data used by Liveview and therefore it won't be possible to use Full-HD in this mode (except 5DIII).
Crop mode seems to bypass this limitation. And it's not quite clear to me either where the data grabbing occurs in this mode and why the Liveview limitation doesn't apply.

There is a very good white paper about Dual ISO written by A1ex. Wouldn't be bothered to see more like this one on some topics. ;-)

Ciao
Walter

PS: When it comes to documention I'm not a role model. I'm just listening to my glass house breaking apart ...

[dmilligan]

I know buffer size isn't important to understand (thanks for the link though), I just like to know what I'm dealing with when I look at things. But if you don't know, it's fine.

Buffer size is simply how much RAM the camera has free (take the two numbers and multiply them, if there are more than one set of numbers, add all the totals. That is the size in MB of that cameras buffer). I agree it would be less confusing to simply put the size in MB on there. Nobody really cares about knowing chunk sizes.

[fillman86]

it seems my reply went missing for the second time O_o

walter, that's very interesting

lenny, in the simplest way, how does being in crop mode increase the amount of pixels your camera can handle?

dmilligan, I thought that may have been the case, but now I want to know what these "chunks" are? Does it have any effect, or is it all about the biggest number?

[Walter Schulz]

http://www.magiclantern.fm/forum/index.php?topic=5441.msg35624#msg35624
covers most of your questions.
Basics in
http://blog.planet5d.com/2013/06/magic-lantern-3x-zoom-triple-every-lens-in-your-bag-new-demo-shows-how/

[dmilligan]

I'm guessing they are contiguous sections of memory. It's probably easier to write into contiguous chunks with the edmac, than to try and split, IDK if it's even possible to split with the edmac (or at least ML might not know how to). So there might be a little RAM in each chunk that we can't use in certain situations b/c we've filled the chunk and there's not enough left over for another entire frame.

This is totally my speculation so someone correct me if I'm wrong.

As for LV resolution, that is just b/c it's what Canon chose to use as the buffer for LV. Nobody knows why its like this except Canon. It does make sense though that they wouldn't buffer the entire sensor when it' not needed, since it's intended only to be used for display. It's probably doing a line skip of every 3 lines, which would put the max resolution at around what it is (~ 5184 / 3 = 1728 width, and the corresponding 16:9 height).

In crop mode you don't line skip, so you can get higher resolutions than 5184 / 3.

Edit: got my width and height backwards

[fillman86]

Okay so the answer I think I was looking for is; In all modes the raw image is coming from live view, and for some reason in crop mode it sends way too much horizontal information?
I suppose even though this is good, the buffer would fill up way too quickly.

Dmilligan, good explanation on buffer chunks ,thank you.

[1%]

Nobody knows why its like this except Canon.

Its based on how sensor resolution divides up into the current mode.. ie crop mode is usually full sensor size/3 (lines read 1 at a time)... just some math goes into this.

The chunks are allocated via software.. canon functions can reconfigure it but I've not found ones that produce more free memory, only less. Canon divides the ram into work units and they go to different processes, some are contiguous some are not.