M2 footage dash and action

Dashmellow said:
Try a good quality dash mat. :)
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Yeah, I will, sometime.... see previous message. In the meantime I have to stick with fiddling with the sunny flippies I made... :( it works to an acceptable extent, but too often I just forget to flip them up after sunset, then the curtains come down.... not cool.

Best would be to plug a filter on it that does it all, but I doubt if that even exists in ANY price range, it seems to be limited by means of physics...
 
dirkzelf said:
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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@dirkzelf gets it!
 
Just been looking at black felt over here, found something interesting at a car stereo store, but out of stock at the moment. ( bookmarked )

I think i have said this before, but i was thinking why not copy the CCTV cameras, and instead of a IR filter put in a CPL filter that can engage and disengage as needed.
I know this will make cameras a little larger, but i cant see that should become so large i would have to pass on it.

Perhaps this is something you can DIY, and then have a pir sensor engage or disengage CPL filter.
 
kamkar1 said:
Just been looking at black felt over here, found something interesting at a car stereo store, but out of stock at the moment. ( bookmarked )

I think i have said this before, but i was thinking why not copy the CCTV cameras, and instead of a IR filter put in a CPL filter that can engage and disengage as needed.
I know this will make cameras a little larger, but i cant see that should become so large i would have to pass on it.

Perhaps this is something you can DIY, and then have a pir sensor engage or disengage CPL filter.
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If you look around on the internet you can buy a solenoid operated IR Cut filter mechanism from a CCTV camera if you wanted to experiment with this idea.

cut_filter.jpg

As for black felt, I assume they must have dedicated fabric stores like they do here in the US where they sell bolts of cloth by the yard or meter. Even our local Walmart has a department like that. I've purchased black felt and black velvet by the yard that way for use as photographic backdrops.You can even find faux black suede like my dash mat is made from. A store like that will have what you need and it is likely to be much cheaper than a car stereo store.
 
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Yeah but the other places it was smaller pieces or not so wide, the place i have bookmarked they have it at 1.5 M wide and as many meters as i want it, so i plan to buy 2 M, that will give me 2 usable size felt to play around with.

Havent looked for some velvet, ill give that a try too.

Yeah i do have 2 of those mechanisms lying around, but they are for CS lenses, but that's still good enough for experimenting.
But i would never get that far myself, i have far too much to do, and slim to none chance of pulling myself together to actually do it.
 
kamkar1 said:
Yeah but the other places it was smaller pieces or not so wide, the place i have bookmarked they have it at 1.5 M wide and as many meters as i want it, so i plan to buy 2 M, that will give me 2 usable size felt to play around with.

Havent looked for some velvet, ill give that a try too.

Yeah i do have 2 of those mechanisms lying around, but they are for CS lenses, but that's still good enough for experimenting.
But i would never get that far myself, i have far too much to do, and slim to none chance of pulling myself together to actually do it.
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Yeah, I believe we are talking about the same thing. Here in the US fabric stores sell bolts of fabric that are a yard (or meter) and a half wide and sold by the linear meter or yard.
Most available velvet might not be the best thing for a dash mat as they can have a sheen to the nap of the fabric that might reflect in the windscreen. I have found some velvets though that don't, and they are great for pitch black photographic backgrounds. They can be hard to find however and are usually more costly.

bolts-of-fabric-pink.jpg
 
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In the US, fabric is sold at a standard width of 54" and except for the very expensive types, there is usually a one yard (36") minimum length charge but they will cut whatever length you need. The benefit of a local shop is they they will know at least a few local people who will make a well-finished product for you ;)

I've recovered a few simple chairs and motorcycle seats in my time. When I figured in my time it wasn't worth it- end of that business venture :p Lots of tutorials and vids about "how-to" on the web.

Phil
 
SawMaster said:
In the US, fabric is sold at a standard width of 54" and except for the very expensive types, there is usually a one yard (36") minimum length charge but they will cut whatever length you need. The benefit of a local shop is they they will know at least a few local people who will make a well-finished product for you ;)

I've recovered a few simple chairs and motorcycle seats in my time. When I figured in my time it wasn't worth it- end of that business venture :p Lots of tutorials and vids about "how-to" on the web.

Phil
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Yeah, 54 inches is a yard and one half, I used the term meter since I'm talking to kamkar in Denmark, but I figured it was close enough to convey what I was saying. My local shops will sell as little as a half a yard and most shops have a handy remnant collection to peruse.

I don't think it would be too hard to create a cardboard template of a dashboard to make a pattern for a DIY dash mat.
 
I already have secured some pretty stiff paper to make templates of, and i have done a visual inspection of my dashbord or rather the edges around the dashbord.
I even think my stainless fiskars scissors will be able to make the cut, so mony i dont have saved there.
 
Dashmellow said:
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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Sorry. I didn't intend the post to come across as patronising. We all have differing levels of knowledge about subjects, and it's impossible to know from 1 or 2 posts on a forum often whether someone is a total beginner, accomplished amateur or total pro, and even then we are all learning from each other.

Personally, I'd suggest the performance of the filter will depend in part, on it's quality, and then the issue is very few people making a DIY polariser are going to pull apart a £50 Hoya lens to do it! Even if you can find a "proper" dashcam polariser, given the cheap prices of these items, often a couple of pounds, you'd have to question the quality. A cheap polarising filter, may be far less effective than a £50 Hoya HD lens.

That said, I do agree that you're not going to stop all reflection. However a CPL should help cut reflection and glare. Certainly, you lose a stop or two of light and so at night I personally wouldn't use one simply because the camera will probably up the gain and thus noise to compensate, so it then becomes a question of glare versus artefacing caused by gain.

If a dash mat helps, with dash reflection, then certainly I see no reason not to use one. I would just personally tend towards using both, at least in daylight conditions.
 
Dashmellow said:
Most available velvet might not be the best thing for a dash mat as they can have a sheen to the nap of the fabric that might reflect in the windscreen. I have found some velvets though that don't, and they are great for pitch black photographic backgrounds. They can be hard to find however and are usually more costly.
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Sounds like you need some of this although I hate to think of the cost though! Probably more than the car is worth: http://www.independent.co.uk/news/s...ial-so-dark-that-you-cant-see-it-9602504.html

If you're looking for matt materials, I think I'd stay away from man made fibres like nylon, rayon, polyester, acetate, viscose, lycra etc as they tend to all have a sheen. Natural fibres such as cotton are more likely to be matt. That probably explains why some velvets are matt and others shiny. Velvet is made from anything from linen fabric (read cotton) to silk to man-made fibres. It's going to be a case of finding a simple black matt cotton / linen fabric. I also personally think that textured matt surfaces such as ridged surfaces tend to reflect less than flat matt surfaces, probably because some light gets lost in the grooves.

On the subject, something that might also help a little, if cleanign your car, instead of using silicone based products on the dashboard, there are some matt finish dash dressing sprays out there.
 
Alsone said:
Sounds like you need some of this although I hate to think of the cost though! Probably more than the car is worth: http://www.independent.co.uk/news/s...ial-so-dark-that-you-cant-see-it-9602504.html

If you're looking for matt materials, I think I'd stay away from man made fibres like nylon, rayon, polyester, acetate, viscose, lycra etc as they tend to all have a sheen. Natural fibres such as cotton are more likely to be matt. That probably explains why some velvets are matt and others shiny. Velvet is made from anything from linen fabric (read cotton) to silk to man-made fibres. It's going to be a case of finding a simple black matt cotton / linen fabric. I also personally think that textured matt surfaces such as ridged surfaces tend to reflect less than flat matt surfaces, probably because some light gets lost in the grooves.

On the subject, something that might also help a little, if cleanign your car, instead of using silicone based products on the dashboard, there are some matt finish dash dressing sprays out there.
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As if on cue some clever soul seems to always mention Vantablack whenever the subject of dash mats comes up. While it is a fascinating invention it is really more of an esoteric scientific curiosity at the moment with limited real world applications thus far outside of high end laboratories and astronomy. What is interesting is that you can actually purchase a range of products that have very similar, albeit not quite such dramatic properties from a company called Acktar - "The World Leader in Black Coatings" They even have an online store. Among other things they make a series of light absorbing foils such as Spectral Black, Metal Velvet and a Super Black Coated Polymer that have specular absorbance as high as 99.99%. These things are not cheap by any means but are not insanely expensive. This stuff is not meant for automotive environments though.

You may be surprised to learn that there are a number of synthetic fabrics including ones you've mentioned that have extremely matte, sheenless properties which are achieved by the processes applied to the fibers during manufacture. You probably won't easily find such velvets or other fabrics in your average bulk fabric shop however.

In the studio, I've used a range of specialty products made for absorbing light depending on the project such as Commando Cloth, Midnight Black Velveteen, and Black Flocked vinyl, which comes in large rolls. Velvets and velours are usually reserved for projects that require draping. I actually used a piece of black flocked vinyl in my vehicle to cure a reflection on my dashboard that the dash mat didn't cover and it is much blacker and more effective than the dash mat which I even customized to enhance its light absorption. Since black flocked vinyl is designed for use under hot lighting it is very durable on a dashboard. It would actually be a great material to make a whole dash mat with.

On the subject of what to use to clean a dashboard with, my Toyota has a dark charcoal grey textured matte surface that was usually so effective I never had too much of a problem with reflections until I acquired the SG9665GC which basically put an end to the "lens close to the windshield glass reduces dashboard reflections" myth, hence my sudden interest in dash mats. In any event, the best way to clean a dashboard is with a soft damp cloth rather than any treatment that makes it shine. In fact, some people believe that repeated use of products like Armour-All will eventually damage vinyl or plastic in motor vehicles by making it brittle, unless of course you keep applying it, like forever. If that is really true then Armour-all is like an addictive drug you need to keep taking.....and buying!
 
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Okay i have grapped a few pictures in the same places off my "old" V1 - SG9665GC and the M2 running 1080/30 and wdr on ( H.265 - 8.5 mbit )

SG1.jpg

M21.jpg

SG2.jpg

M22.jpg

SG3.jpg

M23.jpg

SG4.jpg

M24.jpg


As my GC camera is a V1 it is off course on a pretty raw firmware, the newest public one for V1 cameras i believe, looking forward to see the V2 FW get public and filter back to us with V1 cameras.
The GC frames are grapped using Registrator viewer, to do the same with the H.265 files off the M2 i had to resort to VLC player, and it took me a while to figure out how to jump 1 frame at the time, so some of the pics are not dead on in same place.

But you catch my drift i assume, otherwise ask.
 
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Th M2 wins by a landslide. I'll now be comfortable ordering one when I can afford it and it's next on the list :D

Phil
 
Here's the first screen grabs from my new M2 which arrived today, installed alongside my M1 with the narrower lens A. I took full screen grabs of Quicktime player, both cams on h264. M2 at 1080p60, M1 and 1080p30, both on highest bitrate available. I made the error of rotating the M2 footage 180deg as I do on the M1, but forgot that I don't need to as it's mounted differently, so the M2 time stamps are all upside down :oops: Also didn't sync the date before setting off :oops:

Setting off at 11:10
2016-09-13 11-10-23 M1.JPG

2016-09-13 11-10-23 M2.JPG
Driving 11:14
2016-09-13 11-14-37 M1.JPG

2016-09-13 11-14-37 M2.JPG

Parked at 11:18
2016-09-13 11-18-36 M1.jpg

M2 p1.JPG

Then I left the M2 running for an hour on a USB battery pack whilst I did a few things in town. Ambient temp was about 25 deg C. The car didn't feel unusually hot when I returned to it. However the M2 seems to have suffered some focus shift even in these moderate conditions, particularly around the edges.

Leaving at 12:22
2016-09-13 12-22-55 M1.JPG

2016-09-13 12-22-55 M2.JPG

Before/after comparisons
2016-09-13 11-18 to 12-22 M2.jpg
2016-09-13 11-18 to 12-22 M2 a.jpg
I've not noticed such focus shift before on my M1. Is this something to worry about? I'm feeling inclined to return the M2 and perhaps replace with a C2 lens M1 (so my original M1 can go in the rear window).
 
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