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Messages - desertman520

#1
Quote from: bobolee on May 24, 2023, 10:53:19 AM
I don't like any lens other than Canon EF-M 22mm f/2 STM because of the lens distortion issue of the ML system.If you shoot with the original cannon video function and with a cannon lens,the camera "knows" the lens distortion and will fix it automatically.The MLV APP has no lens distortion correcting function as far as I know,so if you want to get distortion free video,you have to use a lens with minimal distortion,that 22mm 2.0 lens has almost no distortion.

On the Eos M original, only peripheral illumination and chromatic aberration are corrected in camera, not geometric distortion.  However, as other have pointed out, using 1x1 and being cropped in on the sensor makes the best use of the less distorted center of the image circle.

QuoteCCTV lens?The idea itself is a laughable :-*
I humbly submit a posting of a video I made earlier this year using a danne build. 

https://www.magiclantern.fm/forum/index.php?topic=26758.0

It's 2520x1080, shot variously either stopped down or, once it gets dark, wide open.  You may judge the level of distortion, but for a $70 USD lens it would be far more laughable to try and put a hulking piece of glass like a sigma 16mm f1.4 m mount on, or even a viltrox or something for several times the price.  I tell you, it's a gimballer's dream lens.  Some CCTV lenses do have bad distortion, but you can usually check a data sheet ahead of time.
#2
Quote from: bobolee on May 06, 2023, 12:23:26 PM
Only 1080P 3x3 mode will get a wide enough field of view on the Canon ef-m lenses. In door shooting is a big part of practical shooting,due to the big crop factor,most of the "crop modes" is not usable in a limited shooting sapce.

This is why, especially if you already have a gimbal and focus pull system attached, cheap-o C mount lenses are the way to go.  8mm f1.6 and 16mm f1.4 sold by various vendors, such as Arducam, allow for the following equivalent fields of view:
~35mm ff equiv for the 8mm shot at 1920x1080 (its 2/3" imaging circle can't support the higher resolutions)
~55mm ff equiv for the 16mm shot at 2520x1080 (it has a wider imaging circle, so it can be used at higher res)

I haven't done so, but you can get old 16mm cine lenses, new machine vision lenses, etc. in C mount and pay hundreds of dollars for crazy specs just like with normal camera lenses.  Even the performance of the cheapos is pretty solid as long as you don't get a bad copy.  They're $50 and $70 for the 8mm and 16mm respectively...
#3
Share Your Videos / Eos M Dia de los Muertos
January 13, 2023, 09:23:37 PM
The All Souls Procession in Tucson, AZ - afternoon to streetlights/ low light scenario

Eos M, 2520x1080 14bit raw
Danne's crop_rec_4k_mlv_snd_raw_only_2022Oct06
C-Mount 16mm f1.4 lens ($65 "10MP" machine vision lens, 1" imaging circle)
ND8 filter for the lighter parts
Gimbal and monopod for the higher up shots

MLV App -> CDNG's -> DaVinci Resolve

Best at 1080 HD option: