Magic Lantern Forum

Experimental builds (WIP) => Tragic Lantern => Topic started by: ted ramasola on February 06, 2014, 09:48:20 AM

Title: 7D 2048 x 930 resolution chart. How good it really is.
Post by: ted ramasola on February 06, 2014, 09:48:20 AM
The Canon 7D with Magic Lantern raw video+sound is now maturing as a reliable raw camera, this is how good its 2048 x 930 crop mode video looks like. At 23.976fps with no VAF filter.
At this resolution, the 7D can record continuously at 23.976 to fill up a 1000x CF card. Sound is in sync with no drift.

(https://www.magiclantern.fm/forum/proxy.php?request=https%3A%2F%2Fscontent-a-dfw.xx.fbcdn.net%2Fhphotos-prn1%2Ft31%2F1082138_640773202646415_695351585_o.jpg&hash=0dfcb638f24b632757934242baa8ec52)
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: PressureFM on February 06, 2014, 10:14:38 AM
So, what printer did you use and what resolution is that chart?

I'm just asking because a real resolution chart like that starts at $225 and upwards to $950 to get in the correct resolution print.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: ted ramasola on February 06, 2014, 10:18:59 AM
The dimensions of that chart, printed in photo mode, is 29 inches across, so I can still define the lines till the narrowest 1800 nearest the center targets if I would examine it with a loupe. For this shot though I say it still resolved at or between 875-900ish horizontal.

I also have a very large version for my wide lenses at 50 inch across to test for edge to edge sharpness. But for this test using a canon 24-105 lens I just used the smaller one which is 29 in across.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: chmee on February 06, 2014, 12:28:44 PM
i think, its not about the "technical charts"-measurements, but about the real resolution in-picture - and it looks great so far. so, what debayer-algorithm was used (or what app)? near the resolution-perimeter i see typical demosaicing-effects. ("meander"-structure) - and lastly typical debayer-colorshifts - nothing about to worry, i think.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: chroma on February 21, 2014, 09:23:04 PM
Ted,

This is a very interesting and important Thread/Test!  Thanks for getting this going!

Have you tried this test with a medium focal length prime lens (like a 50mm or 100mm)?  I'm one of those cinematographers that believe primes are inherently sharper and produce less distortion than zoom lenses (not always true nowadays!).

In the test shot, what's the focal length?

What f-stop did you shoot at?

I'm going to set up my new Canon AF prime lenses and my old Nikon MF primes and run the same test criteria you've done here.

BTW, 2048x930 is 2.20:1 aspect ratio.  It takes me back to my days of working in 5-perf 65mm film (Super Panavision 70).  Gotta try it myself and get nostalgic!
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: feureau on February 22, 2014, 08:21:45 PM
The 5x zoom mode is amazing. My only problem is getting a proper framing while recording. The hacked mode is too slow strobe-y to get anything right. :(
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: deC9r on February 25, 2014, 11:06:00 AM
well i could test with a tokina 11-16mm 2.8 and a samyang 8mm 3.5 if anybody is interested, however i dont have a high quality chart.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: aace on February 26, 2014, 01:44:22 AM
This is great news. Can anyone help me understand why in 5x crop mode the fps change from 23.976 to 29.951? I've changed it to 24.028 using fps override but it shouldn't automatically change fps, right?
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: ted ramasola on February 26, 2014, 01:58:38 AM
1. If you use fps override, use exact framerate not lowlight so you can get exact 23.976.

2. If your using fps override then that is the framerate of your crop mode video. It does not change.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: aace on February 26, 2014, 03:48:07 AM
1. If you use fps override, use exact framerate not lowlight so you can get exact 23.976.

2. If your using fps override then that is the framerate of your crop mode video. It does not change.


1. Your awesome and thank you for the heads up. Changing low light to exact worked!

2. I didn't make myself clear at the last post. The issue is that when I switch to 5x crop the fps jumps from 23.976 to 29.951. I have to activate fps override whenever I use 5x crop to go back to 23.976. Is this common?
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: ted ramasola on February 26, 2014, 04:03:34 AM
yes. You must use fps override in crop mode and set 23.976fps.

Internally, canon switches to 30fps from 24fps when crop mode is activated. ML FPS override, overrides canon instructions and switches its 30fps back to 24 or 23.976.

If you just use raw most of the time, you can leave your fps override on all the time, before it was not advisable as audio can't be recorded with fps override, now, with MLV raw, audio is recorded even with fps override engaged. Even if you set it to 1fps, audio will always be 24fps.

Just be careful for when you want to record in h264, fps override must be off.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: aace on February 26, 2014, 04:09:30 AM
yes. You must use fps override in crop mode and set 23.976fps.

Internally, canon switches to 30fps from 24fps when crop mode is activated. ML FPS override, overrides canon instructions and switches its 30fps back to 24 or 23.976.

If you just use raw most of the time, you can leave your fps override on all the time, before it was not advisable as audio can't be recorded with fps override, now, with MLV raw, audio is recorded even with fps override engaged. Even if you set it to 1fps, audio will always be 24fps.

Just be careful for when you want to record in h264, fps override must be off.

Thanks a bunch!
Title: 2K video from the 7D
Post by: ted ramasola on March 02, 2014, 12:57:12 AM
Using a KomputerBay 128gig 1050X I shot this piece entirely in 2048 x 930 edited and uploaded to youtube in 2K.

This was all crop mode 23.976 fps using a Canon 24-105mm and a Tokina 11-16mm.

I used Feb 27 TL for this for the FPS over ride function.

Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: arrinkiiii on March 02, 2014, 01:31:48 AM

Very nice, what a superb quality of image!
Title: Re: 2K video from the 7D
Post by: DenJS on March 02, 2014, 06:22:02 PM
Using a KomputerBay 128gig 1050X I shot this piece entirely in 2048 x 930 edited and uploaded to youtube in 2K.
Could you please point to manual which describe how to shoot in MLV RAW with more than 1728×736 ?
Thank you!
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: Walter Schulz on March 02, 2014, 06:28:54 PM
You have to enable crop mode.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: ted ramasola on March 07, 2014, 07:55:08 AM
Relying on the LV while in crop mode to get focus is difficult. The LV is low resolution/pixelized and not in realtime. I made an earlier video in crop mode during a snow in Dallas and the clips were soft and out of focus.
I learned later that cycling through the info button while in crop mode brings up a clean 5X magnify which I can now use to quickly check for focus.
Unlike the 5D2 that you can use the 10x magnify to confirm focus, in the 7D, pressing 10x magnify freezes the lv so I disabled 10x in zoom tweaks ML menu.
When another snow storm hit us in Dallas last week, I quickly went out and retook similar looking scenes and uploaded the clip, this time in 2K in YoutTube. I took down the previous snow video I posted.


Now, if only the devs could find a way to make LV during crop mode give a faster refresh, this will really allow these dslrs to be used seriously due to cleaner image and higher horizontal resolution. I can sacrifice having color in lieu of faster refresh and correct framing.
Title: Re: 7D 2048 x 930 resolution chart. How good it really is.
Post by: arrinkiiii on March 07, 2014, 09:04:41 AM

Yes, indeed....  Good images. Tokina 11-16 rock big time, good for the crop mode =))