F800 Pro availability in US?

[jokiin]

60fps can deliver superior results although not always, lighting plays an important role regardless of which frame rate

 

[TKSX]

There are also other factors as well, such as the angle of how the camera is mounted, the angle of the other driver's license plate, the condition of the license plate, the cleanness of the windows (inside and outside), the cleanness of the lens, the condition of the lens, the reflection from the windows,...etc.

 

[Deleted member 37895]

the frame rate won't change the file size, more frames will give smoother viewing for well lit situations but can be a limiting factor in low light situations, in low light there are some different options with how you deal with that, drop to 30fps, frame double 30fps to keep frame rates consistent, or stick with 60fps and limit the low light performance, there are advantages and disadvantages to each approach

If the compression ratio is the same, then twice the frames in a given period of time will result in twice the file size, it's that simple.

Some cameras intentionally change the compression ratio to maintain bitrate. For example GoPro cameras will do the same 50mbps no matter what resolution and framerate you set.

Of course that means if you have 60 frames in a second using the same amount of storage as 30 frames, you have about half the image quality.

Lighting doesn't matter. Exposure time is independent of framerate. Framerate only sets a cap. At 60fps the longest exposure time is 1/60th second. At 30fps the camera can do 1/30th second. Both are much too long and will turn moving cars into a blurry mess.

 

[Yoon]

Following table is from Blackvue DR750S-1CH manual.

It looks like they will increase the compression ratio for 60fps videos to keep the file size the same. Sounds like huge decrease in image quality.. Am I missing something here?

BTW, I wish F800 offers 12 Mbps bitrate option for maybe a little better image quality.

 

[jokiin]

then twice the frames in a given period of time will result in twice the file size, it's that simple.
.

bitrate determines file size, not frame rate

higher frame rate will show smoother motion

 

[jokiin]

It looks like they will increase the compression ratio for 60fps videos to keep the file size the same. Sounds like huge decrease in image quality.. Am I missing something here?

nothing to do with compression

 

[Deleted member 37895]

nothing to do with compression

If the 60fps video is the same bitrate as 30fps then by definition each frame gets *half* the bits to be encoded... So yeah 60fps would be much much lower quality

 

[Yoon]

nothing to do with compression

Without increasing the compression, how can 1080p@60fps and 1080p@30fps with the same bitrate per second result in the same file size?

 

[jokiin]

If the 60fps video is the same bitrate as 30fps then by definition each frame gets *half* the bits to be encoded... So yeah 60fps would be much much lower quality

doesn't work like that, you'll see smoother video, difference is noticeable at night though but there are other ways of dealing with that as mentioned

 

[jokiin]

Without increasing the compression, how can 1080p@60fps and 1080p@30fps with the same bitrate per second result in the same file size?

you're only talking about how often the CMOS sensor is turned on and off to capture the information, slow it down to a lower frame rate, file size stays the same and you don't get more detail, you get more motion blur in between frame captures

 

[Yoon]

you're only talking about how often the CMOS sensor is turned on and off to capture the information, slow it down to a lower frame rate, file size stays the same and you don't get more detail, you get more motion blur in between frame captures

2x frame rate per second = 2x pictures per second = smoother video. Of course.
2x the pictures with the same image quality = 2x file size
now, how can we make a video file with 2x the pictures, yet keep the same file size? = decrease image quality of each picture.
assuming the same codec will be used, there is no other way.
Please correct and educate me if you know a way to maintain the same picture quality + 2x fps + same file size..

1 minute video of 1080p @ 30fps with 10Mbps takes about 80MB.
You are saying that 1080p @ 60fps with 10Mbps will be able to maintain the same picture quality at 80MB.. It will be smoother, but down in image quality

 

[jokiin]

2x frame rate per second = 2x pictures per second = smoother video. Of course.
2x the pictures with the same image quality = 2x file size
now, how can we make a video file with 2x the pictures, yet keep the same file size? = decrease image quality of each picture.
assuming the same codec will be used, there is no other way.
Please correct and educate me if you know a way to maintain the same picture quality + 2x fps + same file size..

1 minute video of 1080p @ 30fps with 10Mbps takes about 80MB.
You are saying that 1080p @ 60fps with 10Mbps will be able to maintain the same picture quality at 80MB.. It will be smoother, but down in image quality

in very simple terms the setting just determines how often the sensor scans from top to bottom, there's no encoding at that stage, just raw data, faster scan reduces blur due to less rolling shutter effect

you can set two cameras up side by side with one at 60fps and one at 30fps, you're not going to see differences due to being the same bitrate, only smoother video on the higher frame rate

if anyone that has two Mobius cameras wants to try this for themselves set them up side by side, they don't have a 1080p60 option but for the sake of the exercise set one at 1080p30 and one at 1080p15 and record some video while moving, the file sizes will be the same, there won't be any extra detail in the 15fps video, if anything the lower frame rate video has a greater chance of motion blur due to movement and has less detail, in low light situations a lower frame rate can capture more light with each scan of the sensor which can give better results, that's why in low light a lot of cameras that use 60fps will drop to 30fps (or frame double) to get more light in

 

[Deleted member 37895]

in very simple terms the setting just determines how often the sensor scans from top to bottom, there's no encoding at that stage, just raw data, faster scan reduces blur due to less rolling shutter effect

you can set two cameras up side by side with one at 60fps and one at 30fps, you're not going to see differences due to being the same bitrate, only smoother video on the higher frame rate

if anyone that has two Mobius cameras wants to try this for themselves set them up side by side, they don't have a 1080p60 option but for the sake of the exercise set one at 1080p30 and one at 1080p15 and record some video while moving, the file sizes will be the same, there won't be any extra detail in the 15fps video, if anything the lower frame rate video has a greater chance of motion blur due to movement and has less detail, in low light situations a lower frame rate can capture more light with each scan of the sensor which can give better results, that's why in low light a lot of cameras that use 60fps will drop to 30fps (or frame double) to get more light in

You are missing something important. First of all the scan speed of the sensor is unrelated. That is determined by the exposure time the camera decides to capture. 60fps is literally saving 60 frames every second. 30 fps is only saving 30 frames every second.

Imagine 1 second of video. Imagine 30 frames in that second stored in 1 megabyte. They have X quality. Now imagine 60 frames in that second stored in the same 1 megabyte. Do you think the 60 frames and the 30 frames are the same quality even though they take up the same 1 megabyte?

 

[jokiin]

You are missing something important.

likewise, do the test as suggested and see what you get

 

[Deleted member 37895]

likewise, do the test as suggested and see what you get

OK let me try again. Imagine a camera A that captures 1fps at 8mbps. Imagine a camera B that captures 30fps at 8mbps.

Camera A stores each single frame with 1 megabyte. Camera B stores each single frame with 34 kilobytes.

Which image is higher quality the 1 megabyte frame or the 34 kilobyte frame?

 

[jokiin]

doesn't work like that sorry, I totally get that you don't get this, I had the exact same expectation when I started working with higher frame rates

 

[Yoon]

doesn't work like that sorry, I totally get that you don't get this, I had the exact same expectation when I started working with higher frame rates

So, according to your theory, people at Blackvue were just too dumb to create an option for users to choose 60fps/30fps because the file size and video quality will be exactly the same, except that 60fps is only smoother.

You should also email Adobe to remove an option to reduce frame rate in Premiere Pro CC because the video quality won't be affected at all with higher frame rate, keeping the same bit rate..

 

[jokiin]

You should also email Adobe to remove an option to reduce frame rate in Premiere Pro CC because the video quality won't be affected at all with higher frame rate, keeping the same bit rate..

encoding video on your PC is not the same thing, probably why people get confused by this

no idea what options Blackvue do or don't have

 

[Yoon]

encoding video on your PC is not the same thing, probably why people get confused by this

no idea what options Blackvue do or don't have

On Blackvue, you can choose between 1080p@60fps or 1080p@30fps with the same max bit rate of 12 Mbps.
According to your theory, 1080p@30fps option has absolutely zero advantage over 1080p@60fps option because the file size will be the same, image quality will be the same, and 1080p@60fps will only be smoother.
I'm surprised Blackvue engineers have such little knowledge.

 

[jokiin]

On Blackvue, you can choose between 1080p@60fps or 1080p@30fps with the same max bit rate of 12 Mbps.
According to your theory, 1080p@30fps option has absolutely zero advantage over 1080p@60fps option because the file size will be the same, image quality will be the same, and 1080p@60fps will only be smoother.
.

depending on what they do with 1080p60 (lock to 60fps, frame double, or drop to 30fps) in low light then 1080p30 can do better in low light situations, that's not due to bitrate setting though, in normal daylight situations the 1080p60 will be smoother on playback, 12Mbps is pretty low for either but Blackvue have never had particularly high bitrate for various reasons, heat issues, hardware limitations etc

at the moment this is just going round in circles and getting tiring, best to get yourself two cameras of the same model that have different bitrate options and test for yourself