Hi Ladies and Gentlemen, this is my first post and my english is not very good so please be indulgent with me...
I want to share my thoughts with you because Magic Lantern shared so much with us :)
It's about shooting an indifilm in 2,5k (or above) with the Canon 5D Mk III
- There is a good case to believe that CF Cards beyond 1200x (e.g. Komputerbay 256GB) will be released in the near future.
- This will most likely introduce continuous 2,5k RAW recording with the 5D Mk III at 3x crop
- Recording in Crop Mode without line skipping results in a moire/aliasing free and clean image.
- Neverthelss, the 3x crop factor is very impractical for shooting indoors with wide angle and in general (except for telefotographie ;) ).
I know recording 2,5k RAW in Full Frame with line Skipping is not possible.
My workaround is untestet but here it is:
1. Take the Full Frame 5D MK III
2. Equip it with a non Canon Crop lens (Crop factor 1,6 - e.g. Tokina 11-18 DX)
3. Equip that Crop Lens with the Metabone Speedbooster (cropping the image again to 0.71 - ca. 1,4 crop)What you get is an
2,3 crop image with maximum
aperture increased by 1 stop (thanks to Speedboosters light compression).
The whole image is now physically downscaled with a vignette in the center of 5D's Full Frame Sensor.
If you now use the 3x Crop 2,5k RAW mode you will
get close to the original full frame field of view.
I don't know if there are lenses with crop rates above 1,6 that are compatible with 5D MK III and Speedbooster.
I edited a small illustration from metabones.com for this topic:
(http://linkszeit.alfahosting.org/Sonstiges/Speedbooster.jpg)
Cheers!
"There is a good case to believe that CF Cards beyond 1200x (e.g. Komputerbay 256GB) will be released in the near future.
This will most likely introduce continuous 2,5k RAW recording with the 5D Mk III at 3x crop"
Not going to happen! 1200x cards are already introduced, and 5DIII CAN NOT squeeze more than 96-100mb/s of writing speed for RAW recording. That's the camera limitation, and it's been discussed multiple times across the forum. With MLV format, and it's spanning feature there might be a chance, but I haven't tested it myself, so I can't talk about it. Maybe someone who used it can shine, and tell us whether 2.5k in 3X crop at 24fps is possible or not!?!
AFAIK there is no Speedbooster for EF mount ???
On 5D3 I can record continuously at 2240x1260 at 3X with 23.976 fps using Raw format 2.0 (MLV spanned files) using a CF Lexar Pro 1000X and a 45 MB/sec SD SanDisk.
I have a few questions for the original poster:
First of all, why do you want to shoot at 2.5k? Is there a specific reason as to why you picked a resolution that is neither HD nor the new standard of 4K?
Secondly, why do you want to use a camera which imposes very heavy compromises particularly when shooting in crop mode (poor monitoring, heavy magnification of the image, possible inability for the CF card to keep up, no audio)?
There is a camera out there which has been already proven on the field, and can shoot at 2.5k on media which can handle the incoming data quite nicely. It has built-in audio, great interfacing for external monitoring, compatibility with a number of lenses and get this, is actually less expensive than the 5D3.
I am talking of course about the GoPro Black!
No, actually I'm not...hehe...I'm talking about the Blackmagic Cinema Camera which in this particular case seems like a more sensible choice given your specific needs.
However, if you already own a 5D3, and you're dead set on using it for this film, why not shoot at 1920X1080 and make your life a tad bit easier and the shoot a bit more reliable? You can use current CF cards, you don't have to worry about card spanning which IMHO is an unnecessary complication in this case. You'll have useable monitoring, and maybe even built-in audio in a couple of months (which you can use in post to facilitate auto-sync).
Another option would be to shoot at 1920X1288 with an anamorphic attachment. You can then de-squeeze the image in post to a roughly 2500X1288 size which will look very good (based on my own tests). Of course shooting with anamorphic attachments yields other headaches, but that's for a different thread.
The bottom line is that making films is really difficult and complex as it is, why would you want to make your life even more difficult?
Quote from: Midphase on September 21, 2013, 09:44:38 PM
Secondly, why do you want to use a camera which imposes very heavy compromises particularly when shooting in crop mode (poor monitoring, heavy magnification of the image, possible inability for the CF card to keep up, no audio)?
Why? Image quality is superior in cropped mode.
Quote from: Andy600 on September 21, 2013, 09:03:50 PM
AFAIK there is no Speedbooster for EF mount ???
You're right, there is no EF Mount for Speedbooster at the moment. I read somewhere that a simple adapter would do it but there is no reliable source.
Quote from: Midphase on September 21, 2013, 09:44:38 PM
why would you want to make your life even more difficult?
It is a scenario. It is impractical at the moment.
I guess ML will solve many problems in the next 12 month.
I prefer the 5D Mk III because of the better low light capabilities and the image quality in general.
The 3x crop mode has no moire and aliasing problems.
The "heavy magnification of the image" problem is the cause I opened the topic.
In addition to it I want to use the speedbooster to get 1 stop extra and using the side effect of image reduction for the 3x crop mode.
So the negative side effect becomes a positive side effect ;)
You said I could blow up 1080p to 2,5k in post with good results, ok.
So I could blow up 3x crop 2,5k to 4k, that should work, too :)
But of course your right, it makes things even more difficult ...
Quote from: FranzApproxi on September 21, 2013, 10:13:23 PM
But of course your right, it makes things even more difficult ...
No pain, no gain!
Why go through all the trouble? 1080p is more than enough. Besides, there's the BMCC. No one is going to like your film better just because it's in 2.5k.
Quote from: johansugarev on September 22, 2013, 12:41:28 AM
Why go through all the trouble? 1080p is more than enough. Besides, there's the BMCC. No one is going to like your film better just because it's in 2.5k.
I stated my reasons for the trouble.
Of course the story of a film is the most important element but this is a technical ML RAW topic for the
proper use of MK III's 3x crop 2,5k RAW (or above) which is indeed superiour to BMCC in terms of image quality.
By the way, some info's from Metabones FAQ:
Quote
Will there be Speed Boosters™ for DSLR camera bodies?
No. The mirror gets in the way but there is no room for the optics.
So my double crop idea is rubbish, or does anyone has a solution for the speedbooster problem ? ... unplugging the mirror for example?
I mean, it would be great to have such a thing on DSLR's for pushing cheap lenses to other price areas and using the 3x crop in near FF.
Quote from: johansugarev on September 22, 2013, 12:41:28 AM
Besides, there's the BMCC.
Here is a very informative thread about BMCC..
Canon 5D3 RAW vs Blackmagic cinema camera (the 2.5K version)
http://www.magiclantern.fm/forum/index.php?topic=7468.0
Quote from: RenatoPhoto on September 21, 2013, 10:01:12 PM
Why? Image quality is superior in cropped mode.
Monitoring is problematic at best, not sure if things like focus peaking and zebras function as well (but are definitely more impaired by the b/w monitoring). Also, while I have no problem sustaining 1920X1288 on my CF cards, crop mode gave me more than a fair share of messed up frames (even with FPS override and the other various tricks).
I could be mistaken, but I would also say that rolling shutter is bound to be even more amplified at least perceptually in crop mode.
Quote from: Midphase on September 22, 2013, 01:51:04 AM
Also, while I have no problem sustaining 1920X1288 on my CF cards, crop mode gave me more than a fair share of messed up frames (even with FPS override and the other various tricks).
The latest builds are more stable. No pink frames in cropped mode with 5D3.
Quote from: FranzApproxi on September 21, 2013, 08:07:08 PM
2. Equip it with a non Canon Crop lens (Crop factor 1,6 - e.g. Tokina 11-18 DX)
Which doesn't do anything except increase the chance of vignetting. The lens is suitable only on a crop body (due to the optics), it does not provide any crop factor.
It would be impossible to use the speedbooster because of flange distance. Speedboosters can only work with mirrorless systems. Unless you are happy shooting macro only.
Quote from: Audionut on September 22, 2013, 07:26:40 AM
Which doesn't do anything except increase the chance of vignetting. The lens is suitable only on a crop body (due to the optics), it does not provide any crop factor.
I think he means while shooting crop so that effectively you'd only be using the center part of the sensor and lens. I don't think you would have to worry about vignetting when shooting crop.
Quote from: Midphase on September 22, 2013, 08:57:04 PM
I think he means while shooting crop so that effectively you'd only be using the center part of the sensor and lens. I don't think you would have to worry about vignetting when shooting crop.
You're right Sir, that's the point!
I have done tests some time ago with the file spanning (CF+SD) and it was possible to record 2,5k continously in 24fps but in 2,39:1 aspect ratio.
2,5K is not 3x crop, it is called that way but actually it is 2,4x (~2500 out of ~5900 pixels horizontally) so it is like BMCC. 1920x1080 is really 3x.
Quote from: kgv5 on September 22, 2013, 09:37:50 PM
I have done tests some time ago with the file spanning (CF+SD) and it was possible to record 2,5k continously in 24fps but in 2,39:1 aspect ratio.
2,5K is not 3x crop, it is called that way but actually it is 2,4x (~2500 out of ~5900 pixels horizontally) so it is like BMCC. 1920x1080 is really 3x.
Nice! There are a lot of crop lenses suitable for FF (sometimes with adapter) but there we only got a maximum crop of 1,6 as far as I know.
Are there any known "
Focal Reducer" lenses/adapter e.g. for croping EF, DX etc. lenses to much smaller sensor sizes?
I know it would be a big adapter game, but what we would get is a
crystal clear 2,5k FF image on MK III.
Worth the work IMHO... especially if you already own a MK III.
Not necessarily an answer, and it completely depends on your film, but you could just use 1080p non-cropped when 3x crop is too telephoto for the shot/scene. It's not ideal, but you'd have those extra sharp images throughout the film at the very least. I honestly would see a problem with matching the footage... but people have done crazier things, aka matching the crummy 8bit h.264 with 4k raw footage. When that's done right I hardly see a difference, so as long as you pick which mode you use correctly you shouldn't have a problem either.
Just my two cents at least... I could be completely wrong.
Quote from: FranzApproxi on September 22, 2013, 11:31:00 PM
Worth the work IMHO... especially if you already own a MK III.
I'm telling you...you're looking for trouble. Do what you feel you have to do, but be prepared for lots of headaches as well as being hated by your DP.
Yeah, i'm looking for trouble in this hypothetic scenario.
And I should hate myself for being the DP 8)