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05-02-2013, 12:16 PM   #1
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K-01 video dof test rokinon 85mm 1.4

would like to hear suggestions on settings to avoid wobble. These videos were handheld and I do have a Tripod i still think these could be better

Shot with rokinon 85mm 1.4 @ 1.4




05-04-2013, 07:57 AM   #2
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Tripod, and turn off SR.
And from what I'm seeing in the 5minutes after updating my one day old camera to v1.03 firmware, the update improves it substantially.

One tip most people aren't aware off, is that the shutter speed should always be set to a multiple of the frame rate, so if you shot 25fps, then 50, 100, 150, 200, and the higher you go, the less rolling shutter wobble, but the more sports or action-shot the vision appears.
Those shutter speeds represent the time, or number of degrees the shutter would be open, in a film based Cine camera.

Wider lenses help hide camera shake too - the ones in NASCAR / F1 'racecam' onboard cameras are super wide for this reason, ditto the stock glass on a GoPro.
05-04-2013, 09:57 AM   #3
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Thank you for your response!

I was shooting at 24fps since that is a movie industry standard, however the camera was set to aperture priority and it was adjusting the shutter and iso for me. I am going to take SR off for video.

I guess I need to place it in manual and adjust all perimeters and not use aperture priority.
05-05-2013, 12:14 AM   #4
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QuoteOriginally posted by glealisla Quote
Thank you for your response!

I was shooting at 24fps since that is a movie industry standard, however the camera was set to aperture priority and it was adjusting the shutter and iso for me. I am going to take SR off for video.

I guess I need to place it in manual and adjust all perimeters and not use aperture priority.
I'm doing test shots today, got the K-01 on the end of a 14 foot camera jib.

Finding that there's less jello wobble from the camera then there is from when I bounce the jib too fast,...

Side to side pans, or side to side movement only seem to show about the same amount of skew as I've seen on 7D or 5D2, so I'm happy.

The new firmware made it so I could use the SD card the camera didn't like with the 1.0 firmware, but I've noticed a few stutters in the recording during fast movement - same sort of error I've seen DSLRs and video camera, where a few frames get skipped because the data is waiting to be written to the card, so I think choosing better cards is a requirement.

I've been swapping between a SanDisk class 6 'Ultra' 30Mbits card and a Verbatim class 10, which should be faster then the class 6, but it's the Verbatim card that the camera didn't like before, and has dropped frames on.

05-05-2013, 12:16 AM   #5
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QuoteOriginally posted by PiDicus Rex Quote
I'm doing test shots today, got the K-01 on the end of a 14 foot camera jib.

Finding that there's less jello wobble from the camera then there is from when I bounce the jib too fast,...

Side to side pans, or side to side movement only seem to show about the same amount of skew as I've seen on 7D or 5D2, so I'm happy.

The new firmware made it so I could use the SD card the camera didn't like with the 1.0 firmware, but I've noticed a few stutters in the recording during fast movement - same sort of error I've seen DSLRs and video camera, where a few frames get skipped because the data is waiting to be written to the card, so I think choosing better cards is a requirement.

I've been swapping between a SanDisk class 6 'Ultra' 30Mbits card and a Verbatim class 10, which should be faster then the class 6, but it's the Verbatim card that the camera didn't like before, and has dropped frames on.
Besides that I'm looking for a way to lock down the ISO during recording - seems to adjust up and down for correct exposure when the iris gets moved on a manual lens, noticeable as changes in the amount of video noise, or the sky suddenly becoming correctly exposed when the camera tracks up from the ground.
05-31-2013, 02:17 AM   #6
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Here is what I suggest. Get latest firmware. Make sure the correct focal length was input. Don't use random shutter speed and fps - choose the right one for your lens. Save at highest quality, then run it through a video conversion software on the computer (make sure it has the right codecs, some don't work great) to reduce file size and keep quality.
But the "jellow effect" is something that all CMOS sensor DSLRs will exhibit to some degree. Its unavoidable, other than using wider aperture and slower shutter speed to mask it
05-31-2013, 06:12 AM   #7
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Higher Shutter Speed, not lower, will get rid of more Rolling Shutter.

I updated to v1.03 two days after purchase.

When shooting video, fps for me is always 25 - I live in a PAL country.
25fps means 50, 100, 200, 400, 500, 800 can be used for the shutter speed.
You should always use a shutter speed that is a multiple of the fps rate for Cmos cameras. Using any other shutter speed can introduce strobing and horizontal banding in to the vision.

These shutter speeds equate to the number of degrees for which the shutter would be open in a true film camera - double the fps is 180deg, four times the fps is 90degress - It's not a linear progression.
As a general rule of thumb, the more action is going on, the higher the shutter speed you want.
That limited opening of the shutter freezes the action during a smaller amount of time, so less action changes during the period the shutter is open.

Rolling Shutter Jello occurs because the sensor is read out one line at a time, whereas Global Shutter sensors read the whole frame at once.

On a side to side pan, at a lower shutter speed, more can change between reading the top line and the bottom line ( although it's often the other way around - read bottom to top ), then what happens in the smaller time opening of a higher shutter speed.


I don't need to convert anything - I use Canopus/Grass Valley 'Edius' as my NLE. It accepts every acquisition format, and mixes them directly on the time-line.
( A feature it's done for nearly a decade and that Premiere and FCP is only just catching up to now )

In Edius you tell it what project setting you want, and all vision dropped on the timeline is converted to that frame size and frame rate in real time during playback.
Latest version includes both an Anti-Jello filter, and Stereoscopic editing.
Export is to anything from broadcast file formats to Mpeg4. Heck, it'll even output files in the 'Brand-C' version of AVCHD as recorded in their cameras.

That Auto-ISO on K-M and K-A lenses in manual Iris settings is really beginning to annoy me too. If I've set the ISO manually, and the IRIS manually, that means I want them there, not for the firmware to ignore those settings and ramp up or down with AGC on the ISO. Grrrrrrr.

Last edited by PiDicus Rex; 05-31-2013 at 06:37 AM.
05-31-2013, 06:51 AM   #8
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Going back to Glealisla's original post, the correct shutter speeds for shooting at 24fps, would be 48, 96, 192, 384, 768,.... none of which are available.

At NTSC's 30fps, those shutter speeds would be 60, 120, 240, 480, 960, of which only 60 is available.

05-31-2013, 07:06 AM   #9
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QuoteOriginally posted by PiDicus Rex Quote
Going back to Glealisla's original post, the correct shutter speeds for shooting at 24fps, would be 48, 96, 192, 384, 768,.... none of which are available.

At NTSC's 30fps, those shutter speeds would be 60, 120, 240, 480, 960, of which only 60 is available.
Given that - would it be best to shoot with 25FPS as opposed to 30FPS?
How disadvantageous is it to shoot 1/125 or 1/250 for 30FPS vs 25FPS?
06-03-2013, 05:44 AM   #10
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That depends on where in the world you are Jin.

Here in Australia, broadcast (and all our TV's) work at 25p / 50i. So 25fps is best for me, unless I need footage to match a film that is going to 'print' for cinema release, in which case I can use 24fps.

In NTSC countries, such as the USA, the TV's and Broadcast networks run at 30p / 60i, so you'd shoot at 30fps there for playback there. And drop to 24 for Film work.


TV Standards Joke.....

NTSC,.
Real Meaning - National Television Standards Comittee.
Repair Guy Meaning - Never Twice the Same Colour.
PAL,.
Real - Phase Alternating Line
Repair Guy - Perfect At Last.
SECAM (French,....)
Repair Guy - System Essentially Contrary to the American Method.
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