Videos not sharp enough?

SotY

SotY

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Could somebody take a look at attached sample recording and tell me if I'm right thinking that recordings should be sharper? You can't read any plate on the cars that I was passing. I was driving at around 25 mph and cars on the left stopped. Weather was also good for camera I think. I'm running latest public beta and have CPL installed.

http://vmc-pl.net/temp/test.mov
 
will download and have a look, is going to take a few hours from where I'm at right now, @Street Guardian USA might get to it before I get a chance to check it

have you tried without the CPL as well?
 
That looks normal; about what you might expect in those conditions driving on a slightly bumpy road surface with moving vehicles out in front of you. If you test the camera against a stationary object, say while you are parked facing a storefront things will probably look much sharper.

Some members have experienced focus issues with the SG9665GC but your camera seems fine. An out of focus lens will be more obvious.
 
still waiting for the download to finish, lighting, motion, time of day etc all play a part in the end result of what you can or can't capture, a CPL filter can also take the edge off things, a static location like a store front as @Dashmellow mentioned is the ideal situation to look at the actual focus
 
Yes, as jokiin just mentioned, one factor here is that your footage was shot on an overcast day with the CPL filter on the camera. Under the identical driving situation on a bright sunny day your video will be sharper and more detailed.
 
What you're seeing is motion blur. An issue I have brought up on some occasions.
I would think you'd have to ba able to make out licenceplates of cars that you're passing at this moderate speeds.
I would not mind a bit more noise if the exposuretimes was shortened a bit, but others might, so it would have to be a user controlled setting.
 
Dashmellow said:
Under the identical driving situation on a bright sunny day your video will be sharper and more detailed.
Click to expand...

Yup, this is todays 'ISO100' weather. I'm doing about 50km/h and so are the cars coming the other way. Exposuretime nice and short, crisp as a packet of crisps
 
Feitelijk said:
What you're seeing is motion blur. An issue I have brought up on some occasions.
I would think you'd have to ba able to make out licenceplates of cars that you're passing at this moderate speeds.
I would not mind a bit more noise if the exposuretimes was shortened a bit, but others might, so it would have to be a user controlled setting.
Click to expand...

Shorter exposure times might create other issues, depending on the conditions one is driving in. From my experience, newer technologies such as higher frame rates and different, perhaps slightly larger sensors will ultimately be required to better capture moving objects.

BTW, @Feitelijk, speaking of motion blur, a few days ago someone drove past me in the opposite direction in a car identical to yours, even the same exact color. I had to do a double take. :p

Feitelijk.jpg
 
This is worse lighting:
 
Nice car, looks like a Caterham!
Dashmellow said:
From my experience, newer technologies such as higher frame rates and different, perhaps slightly larger sensors will ultimately be required to better capture moving objects.
Click to expand...
Framerate? No that's not going to fix anything, light i what you need. So a faster lens (F1.6 of F1.4) and indeed bigger sensors.
When's the first ASP-C cam coming?
 
There are some discussion threads here about frame rate and reduced motion blur with documentation and examples but that is probably a discussion for those threads not this one. I'll try to remember where those threads are.
 
Frame rate is just the frequency at wicht the images are taken.
Motionblur is how much the object moves in the exposure time.

Exposuretime is obviously limited to the inverse of the framerate but you can make it shorter than that.
If you were to take images at let's say 90hz and smartly (with proper displacement of parts of the image ) average three of them you could get a sharper image but there's no way processors can do that at the moment.
 
Feitelijk said:
I agree that this is not the place but I do not agree with your arguments made in those posts. If you have the time: http://nofilmschool.com/2015/09/how-shutter-speeds-frame-rates-change-look-feel-of-film
Click to expand...

So apparently, although you agree this isn't the place to have this discussion, you do it anyway. OK, that video has been rolled out here on DCT too, long ago. If you actually pay attention to what they are saying it is not relevant to this discussion. The narrator is talking about artistic intent in filming making. He goes on to talk about making shutter speed and frame rate decisions in film making designed to "Really impact our audience" and what he describes as, "It just feels right". He further speaks of setting your frame rates and shutter speeds "In a way that is FITTING to the story you are telling" This has nothing to do with what we seek in dash cam footage, how dash cams function and it ignores issues such as refresh rates in playback as well. We are seeking absolute documentation, not emotional, artistic story telling.

Personally, I will go with the facts as spelled out in the post I referred to and the documentation links rather than filmmakers giving biased tutorial about how to "adjust" the frame rate/shutter speed ratios in order to achieve a particular artistic effect in the service of storytelling. Those arguments and opinions were not mine btw but those of the director Peter Jackson, the special effects master Douglass Trumball and the manufacturer of the RED Digital Cinema cameras.
Actually, the various filmmakers are basically saying the same thing but they differ on the value and uses of employing higher frame rates in cinema.
 
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I linked the video because of the tennisball example. You see the ball sharp at a short exposure, not at a higher framerate.
You started about the difference between photographic and film, the video explains this as well. It makes it choppy if you use short exposure.

It you want to record licenceplates and no motion blur, you need short exposure and who cares about the choppy frantic videoplay?
 
If I do a print screen on that, I see more motionblur on the 25 FPS than the 60 FPS. Explain.

From there:
"Motion blur is a natural effect when you film the world in discrete time intervals. When a film is recorded at 25 frames per second, each frame has an exposure time of up to 40 milliseconds (1/25 seconds). All the changes in the scene over that entire 40 milliseconds will blend into the final frame. "

Show me the same 60 fps and 25 FPS where BOTH exposure times are equal.
 
Feitelijk said:
If I do a print screen on that, I see more motionblur on the 25 FPS than the 60 FPS. Explain.

From there:
"Motion blur is a natural effect when you film the world in discrete time intervals. When a film is recorded at 25 frames per second, each frame has an exposure time of up to 40 milliseconds (1/25 seconds). All the changes in the scene over that entire 40 milliseconds will blend into the final frame. "

Show me the same 60 fps and 25 FPS where BOTH exposure times are equal.
Click to expand...

That is a computerized simulation used for illustration and demonstration. A screen print is meaningless.
 
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