SG9665GC High Contrast/Dynamic Range Flaw and other Discouragements

[kamkar]

Wrap that hood in a old white bedsheet and go for a test drive.
Thats actually the way for ordinary ppl here to do ambulance driving them self, will proberly be more and more needed as those services get downsized here too.

I will try my best to amp up my results in the days to come, ill be dammed if i am allowing some yank get even more messed up footage then me

 

[Dashmellow]

it's not to the extent you were getting though which was quite severe, was yours worse though because of the extra dark section in the lower part of the screen, at this stage I'm not sure but always looking to establish any patterns

Some of @kamkar1's screen shots, especially the fifth one down are definitely examples of the same phenomenon though, and without the dark vehicle hood as a factor. Establishing that this is occurring in a range of units and particular lighting scenarios beyond what I've been reporting seems like half the battle.

I hope to have some time over the next several days, along with the right weather / lighting conditions to do some testing in reference to the amount of dark hood in the image. Some brief testing today suggests that the amount of dark vehicle hood in the FOV may indeed be a factor here but so far it seems to be more of a symptom than a cause, In other words, I'm starting to think the problem is something inherent in the camera that is exaggerated by a dark object in the FOV under certain lighting conditions rather than the dark object being the sole cause. @kamkar1's screen shots seem to support that theory.

Just checked and it looks like the next several days will be rainy, snowy and overcast, so testing may be awhile yet.

 

[jokiin]

I'm starting to think the problem is something inherent in the camera that is exaggerated by a dark object in the FOV under certain lighting conditions rather than the dark object being the sole cause. @kamkar1's screen shots seem to support that theory.

I'm leaning towards it being a metering issue and we'll need to look at the values in the AE table to better weight it toward what we need to capture

 

[kamkar]

Forcast here is allso less than optimal, but then again the least trustworthy ppl here is weathermen and ther forcasts, so i take weather day by day.

 

[Dashmellow]

Forcast here is allso less than optimal, but then again the least trustworthy ppl here is weathermen and ther forcasts, so i take weather day by day.

I know what you mean! It seems like even with all the computers and satellites these days they sure do miss the forecasts sometimes. Where I live though, there's an old saying....."If you don't like the weather just wait a few minutes."

 

[DT MI]

...Where I live though, there's an old saying....."If you don't like the weather just wait a few minutes."

Hmmm, from your signature I would never guess you're from Michigan (same thing applies here).

 

[Dashmellow]

Hmmm, from your signature I would never guess you're from Michigan (same thing applies here).

It is allegedly an old New England saying but it wouldn't surprise me to hear it in use in any Northern US state. It sure is true where I live, I can tell you that!
As I mentioned elsewhere, just recently it went from 15 degrees below zero to the mid 60's in maybe a twelve hour period. This morning it was snowing but now it's a nice sunny springlike day.

 

[DT MI]

...
As I mentioned elsewhere, just recently it went from 15 degrees below zero to the mid 60's in maybe a twelve hour period....

Yep, saw that post. The most extreme I've personally seen was a near 50 degree (F) drop in less time than it took to play a round of golf (I know, I was there). Went from mid to high 80's to under 40 in a matter of 5 hours.

 

[Dashmellow]

Yep, saw that post. The most extreme I've personally seen was a near 50 degree (F) drop in less time than it took to play a round of golf (I know, I was there). Went from mid to high 80's to under 40 in a matter of 5 hours.

This winter we've had the craziest weather I think I've ever seen. Things are getting downright spooky and there are still those with vested interests who claim that climate change isn't really occurring. (regardless of the cause)

 

[kamkar]

Got footage today, but lost x camera with footage to compare, will go look for x cam tomorrow with metaldetector

 

[kamkar]

pice of advise, dont strap camera to new dog collar, tho the belt clip of the x cam is strong it dident want to stay put on collar, thank god i have a pretty good idea where it might be.

Othewise i would be screwed as i was on a 1 hour / several Km walk with the great dane dog, but i cheked camera ever so often so i know its within a fjew 100 M of forrest trail.

Worst par is my brand new PNY U3 card is in the camera too, that just elevate the potencial loss to frightning levels

 

[arcticfire]

pice of advise, dont strap camera to new dog collar, tho the belt clip of the x cam is strong it dident want to stay put on collar, thank god i have a pretty good idea where it might be.

Othewise i would be screwed as i was on a 1 hour / several Km walk with the great dane dog, but i cheked camera ever so often so i know its within a fjew 100 M of forrest trail.

Worst par is my brand new PNY U3 card is in the camera too, that just elevate the potencial loss to frightning levels

Whenever I'm in PC World I keep checking out the action cams but couldn't really justify one at the moment, but I never thought about strapping it to a dog! We've got a Beagle who loves to go romping in the woods off the lead, I've already got a GPS tracker which connects live to an app on my phone but it would be great to see what he gets up to also! Great idea! Time to shop

 

[flip9]

I don't view my dashcam footage often but just to add to this, im getting the same as Dashmellow.

The sky and many scenes is blown out. I thought i just needed a CPL but apparently not. I compared it with some old mini 0806 footage.

I don't know if its my black hood throwing off the metering. Perhaps add a more center weighted option?

I also noticed that even when my hood is reflecting light, the AE isnt dropping to a suitable -EV.

 

[Dashmellow]

So, yesterday I went to the trouble of remounting my SG9665GC so I could test it out with the hood of my vehicle completely eliminated from the camera's FOV. While there were some situations where removing the dark truck hood from the image did seem to improve the results, the bottom line is that the issue I've described as the "High Contrast/Dynamic Range Flaw" persists.

 

[jokiin]

thanks for taking the time to try this out, even it's much better there's still need for improvement and I think it highlights the need to look at the AE table, these pics along with your older ones are very useful to demonstrate the difference between dark hood/dash and no dark hood/dash in the bottom the frame and how the camera is behaving in these high contrast situations, will need to look at how we can customise the AE table to suit with and without that dark section in the bottom of frame, then we can look at getting the contrast balance right

 

[Dashmellow]

@jokiin, I confess that I don't know too much about how AE tables work in the firmware but as we've discussed via PM, I maintain that the problem is more one of tonal range/dynamic range control rather than merely exposure metering. The overall exposure in the screen shots above is not poor. Instead, the upper third of the contrast curve is completely missing. Certain conditions seem to push the camera over some sort of tonal control threshold.

Here is an older screen shot from last October. The overall image is properly exposed by any standard but the camera drops the ball when confronted with an object of luminous intensity.

 

[jokiin]

I agree with what you're saying but I believe we need to adjust the AE metering table to prevent it behaving the wrong way in the first place, both need adjustment but I think we'll need to do the AE table first, that's all

 

[kamkar]

Poking this a little more with a stick.
This is captured yesterday with the 07 beta FW, i allso tilted the camera a bit up to give it a overwhelming sky to work with.

Into the fire ( as the lyrics for a old Deep Purple track goes )

Having the sun over the shoulder is no issue, like the blue sky, need more of that stuff in the months to come.

Into the fire again, this time with even less skies to white out things.

Same spot i have just turned right, the SG9665GC like this.

And for the last pic i saved this night picture, thats the moon at the "end" of the road.
I do like the color of that night sky, the other white blob to the left of it is a oncomming car.

Here is the 3 minute file where the 2 middle pictures come from ( where i turn right )
For the nosy ones thats the O2 ring road in Aarhus and i turn right onto route 26 that goes to the town of Viborg about 65 km avay.

https://mega.nz/#!6sg2WKaQ!unmlFB4o-3ebeZwEZvFf42GVO0pQxBtm8fqR38Y_Njk

 

[jokiin]

most of the issue you have there relate to reflection, think we need to send you a CPL so you can do some comparison testing of these situations with/without

 

[kamkar]

Yeah the reflections are murder thats for sure.
As i undestand it the SG CPL filters are now factory calibrated so that would make on/off testing a whole lot easier for sure.

Taking the camera off the mount after i relocated it a little lower on my windscreen is a pleasure now, i know it was a bit high on my windscreen before, but i still dont get why it was so damm hard to get off before.
Also the mount rattle been killed by the foam pad, though i rarely use microfone it is now much less aggravating to listen to the recordings.
Still have a weak high pitch whine from my 5 port charger, but soon that charger will be relegated to only charge/power non dashcam related stuff.

Looking for dashmats too but still invane, i totally forgot this car of mine is a shared platform, so i completely forgot about the simmilar Opel Agila and others
But so far i have no luck when housesitting for my little sister this summer i might enlist my nice to help me make a DIY dashmat.