M2 footage dash and action

Okay so i ran into a couple of problems.

1. i still cant upload H.265 to the outdated youtybe servers.
2. there seem to be a issue with the M2, no matter what you select the camera use VBR ( Variable BitRate )
3. Mega.nz was not working for me right now, so i put the file on my G-drive
4. The daytime footage suffered from dashbord reflections as today was really nice and sunny for the most of the day, so i desided against using daytime footage.

So instead i have a file from when i drove home at dusk ( 20:00 ) so its halfway night footage or at least low light footage.

recording settings: 1080/60 - H.265 - standart bitrate (VBR ) so AVG bitrate is about 21 mbit.

https://drive.google.com/file/d/0B36pu7lzytG1Ml9iWWtIWlFlVTA/view?usp=sharing

This is just a single 3 minute file, 353 MB in size.

Location driving west on route 26 out of Aarhus, starting at the O2 ring road.
 
I take it there's still no circular polariser option then?

If so it's a real pity as I've watched most of your videos and the overhwelming thing spoiling the clarity of the daytime versions is not the camera or lens but the reflections.
 
No for any mobius camera a CPL filter is something you have to make yourself, these cameras are after all action cameras, the dashcam functionality is just a perk.

I am playing with the idea of trying to fit a CPL filter from my joovuu X camera, but i have to do some DIY to make the 2 fit together.
I could also fit the camera to the outside of my car with a suction cup just like i did with the x camera a while back, then you will see reflection free footage, but than its also not real world footage.

I do think CPL filters will be a standard feature on future dashcams, if you cant have a dashmat ( like me cuz i cant fine one for my brand/model of car ) then a CPL is the only solution.

Problem with mobius is you have no way of previewing, and so also no way to see if your CPL filter are adjusted just right.

Only way is to use the supplied FPV harness and then connect a LCD monitor.
 
Okay to go totally overboard here is a link to a 855MB download, that's what you get when you record a 1080/60 - H265 File at the highest bitrate setting ( just under 40 mbit )
https://mega.nz/#!yxgwDDzR!vaSfCgDKrWgI2vcoMgi0xCsroR0wclXqyaViI7Hs7N8

Its cloudy today so my drive to do a little shopping is fairly minimal in regard to dashbord reflections.

855 MB :eek: thats totally insane for 3 minutes of dashcam footage, not something i would use with a SD card based camera.
But on a HD/SSD based camera with a possibility to transfer files from main unit to a memory stick i would use that setting or similar in a heartbeat.
 
Yesterday you said the M2 used VBR whatever the bitrate setting. Is that variable within the highest/higher/high/standard/low/lower/lowest options?
 
Yes there seem to be a bug in this regard, cuz if possible i always try to use CBR ( Constand BitRate ) but that setting don't seem to take to the camera, so i see recordings in low light is much lower than recordings in bright light where the camera can see a lot of details to record.

Its not really like VBR is bad in any way, to be honest i think its pretty smart not generating say 500 MB files at night when you can only see a little illuminated by your headlights.
Its just me that's a old conservative git in the case of CBR/VBR :D dont think there is any gains using a high CBR in low light, cuz then the major problem is motion blur generated by camera using slow exposure timings to make a bright picture, and i don't think a high bitrate would make any changes in that regard.

I have not tested if VBR the case with all the bitrate settings you can choose, but i think if its the case with 1 setting its properly the same with all settings you can select.
But the selection of CBR or VBR is a general setting and then apply to all resolutions - bitrates and the 2 modes selected by the user.

I think this should be a easy fix, just one of those little things than can slip by in the rush to get a product out the door.
 
kamkar1 said:
No for any mobius camera a CPL filter is something you have to make yourself, these cameras are after all action cameras, the dashcam functionality is just a perk.

I am playing with the idea of trying to fit a CPL filter from my joovuu X camera, but i have to do some DIY to make the 2 fit together.
Click to expand...
The lack of CPL support may be one reason I go for something like SG9665GC rather than the M2, when upgrading from my Mobius1. I'm happy to try a DIY CPL if it can be left on 24/7.
 
TonyM said:
The lack of CPL support may be one reason I go for something like SG9665GC rather than the M2, when upgrading from my Mobius1. I'm happy to try a DIY CPL if it can be left on 24/7.
Click to expand...

The black brushed suede dash mat I installed in my vehicle is so effective it essentially negates the need for a CPL. That is something to consider against spending more than twice the money on an SG9665GC (plus the cost of the CPL). Of course, with the GC you'll have a screen, GPS and other features.
 
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Yeah i keep forgetting to buy a black towel or something i can trow on top of my dashbord, i really got to remember that soon.

A black "rag" can off course only be a temporary solution for me as i have that compartment on top of the dashbord and dead center, and i cant block it as i often use it for my tablet that i have allso begun to use with a app telling me where the police have their ATK cars placed.

But other than that i don't mind having something draping my dashbord, my car is not signaling anything except maybe don't drive like a dumb ass near me, and my owner is not the kind of guy trowing crap out of the window, he just trow it in the car and then clean it once in a while.

I would kill for a proper dashmat that's for sure :D

And bar the issued on the windscreen, any mobius would be a good rear or side camera, that's for damn sure :)
 
In addition to reflections off the dash, I also get them off the road during my spring and autumn driving to and from work, so I think a CPL is probably better for me. I'll still look into the dash mat though.
 
TonyM said:
In addition to reflections off the dash, I also get them off the road during my spring and autumn driving to and from work, so I think a CPL is probably better for me. I'll still look into the dash mat though.
Click to expand...

I've never found a CPL to be very effective against road glare. That's a different problem in terms of polarized light and it is wishful thinking to expect a CPL to fix that because a CPL cannot ameliorate light coming at you from very different and multiple angles at the same time. Either you use a CPL to polarize the light reflected off your dashboard against your windscreen or perhaps try to use it to fix the constantly shifting light reflecting off the road surface but it won't do both at the same time.
 
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kamkar1 said:
Yeah i keep forgetting to buy a black towel or something i can trow on top of my dashbord, i really got to remember that soon.

A black "rag" can off course only be a temporary solution for me as i have that compartment on top of the dashbord and dead center, and i cant block it as i often use it for my tablet that i have allso begun to use with a app telling me where the police have their ATK cars placed.

But other than that i don't mind having something draping my dashbord, my car is not signaling anything except maybe don't drive like a dumb ass near me, and my owner is not the kind of guy trowing crap out of the window, he just trow it in the car and then clean it once in a while.

I would kill for a proper dashmat that's for sure :D

And bar the issued on the windscreen, any mobius would be a good rear or side camera, that's for damn sure :)
Click to expand...

Some inexpensive black felt from a fabric store can make an excellent DIY dash mat.
 
Dashmellow said:
I've never found a CPL to be very effective against road glare. That's a different problem in terms of polarized light and it is wishful thinking to expect a CPL to fix that because a CPL cannot ameliorate light coming at you from very different and multiple angles at the same time. Either you use a CPL to polarize the light reflected off your dashboard against your windscreen or perhaps try to use it to fix the constantly shifting light reflecting off the road surface but it won't do both at the same time.
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That's a bit disappointing. Perhaps I am expecting too much from a camera CPL. I often wear polarised glasses when driving which appear to cut down both dashboard and road reflections.
 
TonyM said:
That's a bit disappointing. Perhaps I am expecting too much from a camera CPL. I often wear polarised glasses when driving which appear to cut down both dashboard and road reflections.
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A CPL (circular polarizer ) is different than the linear polarizers that are used in sunglasses and also your eyes work differently than a wide angle camera lens. Also, with sunglasses you are constantly adjusting and moving your eyes and tilting your head in ways your camera is not. A CPL will help with road glare but is better for windshield/dashboard reflection.
 
TonyM said:
That's a bit disappointing. Perhaps I am expecting too much from a camera CPL. I often wear polarised glasses when driving which appear to cut down both dashboard and road reflections.
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A CPL will work exactly the same as the sunglasses, the only difference is that your glasses will be a little further back from the glass so will see the reflections at a slightly different reflection angle which may make them slightly more, or slightly less effective depending on the angle of the glass since the proportion of reflected light that gets horizontally polarised depends on the reflection angle.

A CPL contains a linear polariser, exactly the same as sunglasses. The C (circular) part is not actually used by a dashcam and makes no difference, it is not needed. Reflected light from both windscreens and the road becomes exactly horizontally polarised, a vertically aligned CPL and sunglasses which are always vertically aligned unless you hold your head at an angle will work equally effectively for both.
 
Dashmellow said:
I've never found a CPL to be very effective against road glare. That's a different problem in terms of polarized light and it is wishful thinking to expect a CPL to fix that because a CPL cannot ameliorate light coming at you from very different and multiple angles at the same time. Either you use a CPL to polarize the light reflected off your dashboard against your windscreen or perhaps try to use it to fix the constantly shifting light reflecting off the road surface but it won't do both at the same time.
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The I'd suggest that either it wasn't a very good quality polariser, or it wasn't adjusted correctly.

A matt dash matt, whilst it will help for internal reflections, certainly won't stop external reflections whereas a polariser should make the glass clearer and more see through as a result of reducing almost all reflection. That's why there so popular with photographers. If you're talking about road glare, then I presume we're talking a wet road here. A CPL should help with that as CPL's reduce light reflections from water, which is pretty much why CPL's are de rigor with all photographers especially as they have the bonus property of increasing contrast / colour saturation.

BTW, a circular polariser needs to be adjusted by rotation to find the best angle for it work. If you use it unadjusted the result can be anything from weak to non existent.

The beginning of this video shows how a properly circular polariser correctly adjusted should improve the picture:

 
Alsone said:
The I'd suggest that either it wasn't a very good quality polariser, or it wasn't adjusted correctly.

A matt dash matt, whilst it will help for internal reflections, certainly won't stop external reflections whereas a polariser should make the glass clearer and more see through as a result of reducing almost all reflection. That's why there so popular with photographers. If you're talking about road glare, then I presume we're talking a wet road here. A CPL should help with that as CPL's reduce light reflections from water, which is pretty much why CPL's are de rigor with all photographers especially as they have the bonus property of increasing contrast / colour saturation.

BTW, a circular polariser needs to be adjusted by rotation to find the best angle for it work. If you use it unadjusted the result can be anything from weak to non existent.

The beginning of this video shows how a properly circular polariser correctly adjusted should improve the picture:

Click to expand...

Well, thanks so much for explaining photography and CPLs to me. ;)

Your video doesn't exactly address what I am talking about, especially because it is a night time demonstration but it does address what CPLs do for windshield reflections.

Linear polarizers and circular polarizers don't quite work the same way as @Nigel points out but if you adjust the CPL for reflections coming at the lens from a specific angle of reflection it will be out of phase with reflections coming from a different angle within a range of about 15 to 30 degrees. This is why depending on the placement of your camera you may have to adjust the CPL for an optimal compromise to accommodate the curvature of your windscreen. It will not universally null all reflections coming at you from all directions in an automotive environment as many here seem to believe.

Personally, after much experimentation I've concluded that I don't care for CPLs on dash cams even though I have used them from time to time. Despite claims that certain CPLs do not compromise night time performance, they are defacto ND filters. The ND effect can also slightly increase motion blur during the day. CPLs behave in fact even more like ND filters than a linear polarizer due to the extra layer of polarizing material in its construction. I've also noticed that in some circumstances that putting another layer of glass over your existing lens in the form of a CPL on a dash cam can have it's own set of issues depending on the particular lens and CPL combination.

Because the SG9665GC is so prone to dashboard reflections I decided to try a dash mat thinking it might help. I was blown away by how effective it was to the point where I basically gave up on the problematic CPL made for the GC (earlier version from a year ago, since revised). Actually, truth be told, the combination of the CPL and a dash mat is quite remarkable but I found it to be essentially unnecessary. Any reflections I do see are usually way up on the corners of the image while the severe dashboard reflections that plagued me are nowhere to be seen. See the images in this post for an example of a proper dash mat's effectiveness. You'll notice a few extraneous and subtle reflections here and there but of no real consequence but you will not see the dashboard reflected in the windscreen at all. That has been my universal experience with the dash mat whereas without it these images would be rather poor.

People should ultimately do what makes them happy and what works for them. Kindly remember that this discussion arose from a member questioning the purchase of camera that doesn't come with or have available a suitable CPL, so I suggested that all he needs is a good dash mat and I stand by that recommendation. The primary concern with dash cams is reflections of the dashboard in the windshield. Constantly shifting road surface reflections are essentially a non issue.
 
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Dashmellow said:
I've never found a CPL to be very effective against road glare. That's a different problem in terms of polarized light and it is wishful thinking to expect a CPL to fix that because a CPL cannot ameliorate light coming at you from very different and multiple angles at the same time. Either you use a CPL to polarize the light reflected off your dashboard against your windscreen or perhaps try to use it to fix the constantly shifting light reflecting off the road surface but it won't do both at the same time.
Click to expand...

Correct, I've tried (and weird enough keep trying....) to find a good all covering diy cpl filter.

No success so far ....
 
TonyM said:
That's a bit disappointing. Perhaps I am expecting too much from a camera CPL. I often wear polarised glasses when driving which appear to cut down both dashboard and road reflections.
Click to expand...

That's true, but light comes in different temperatures, and from different angles, it can reduce a lot, but when turning the car the glare may return in another spot, or angle. It's a bit difficult to explain, but the angle of the windscreen has something to do with it as well.

I drive big trucks and they all have dead vertical windscreens ("aerodynamics are for guys who can't build engines" - Enzo Ferrari). I practically have NO glare at all in those trucks , but in my 2014 Fiat Punto all hell brakes loose in the glare department.....

Going to look into that dash mat thingie for that, cause it creeps my corn by now. :D
 
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