SG9665GC High Contrast/Dynamic Range Flaw and other Discouragements

[Dashmellow]

Last week in another thread (Feitelijk's SG9665SC) I promised to post some comparison examples when I had the time regarding an issue I've experienced that @Feitelijk was reporting and attempting to demonstrate. I decided instead to create my own separate thread since that is @Feitelijk's thread about his SG experiences and I want to keep this posting focused primarily on this one particular issue and Dashmellow's SG experience, however anyone reading this thread would benefit from clicking on the above link and reading a few posts down in order to put this thread into context.

So, I've owned the SG9665GC for just about a year now and am sorry to report that I've been very unhappy with an important aspect of the camera's performance that is bad enough that it has had me contemplating taking it out of service completely. I say that as someone who has experienced this problem with three different SG units, different firmwares, calibrations, a dash mat, and two different CPLs. The issue is that the camera appears to have a serious inherent flaw in its ability to handle bright, high contrast, high dynamic range situations where large sections of the image become blown out in bright glare to the point where entire cars and other important aspects of the scene in the road in front become completely obscured.

I want to be clear that the reason I've considered taking the camera out of service is that the problem is so severe and happens so often in my travels that I consider it unacceptable. It's become more than a mere annoyance as I would never want to find myself in a situation out on the road and find out only later that the camera failed to capture it. This is especially so as I have proven to myself that no other camera I own has this problem. (as you will see below)

This often occurs during the transition from shaded, lower contrast areas to brighter ones but can happen at other times as well when the sensor appears to become overwhelmed by bright light and large areas of the image become blown out in glare. Since I live in a rural area where I am constantly driving in and out of a canopy of trees and shadows of steep mountains or hillsides it presents a problem that can often manifest every few minutes or even seconds of driving.

Most dash cameras experience some challenges in bright conditions to one degree or another, especially when traveling from one dynamic range environment to another such as passing under a bridge or going through a tunnel but the issue here is that the problem is far more severe than I have ever seen and no other camera I've owned regardless of cost experiences this flaw under identical circumstances. While most cameras that have an issue recovering from the glare of passing through a tunnel will recover very quickly the SG not only manifests the problem more severely but takes much longer to recover. Also, as I've said, you don't even have to be going through a tunnel for this bright white out glare issue to manifest on the SG9665GC.

Originally, I intended to post a thread about my experience much like the one I'm posting here but instead, the way things have worked out I've spent months working behind the scenes with @Pier28 and @jokiin attempting to analyze and resolve the problem. It will come as no surprise for anyone here to hear that both Rick and Jon have been extraordinarily courteous, friendly, helpful and generous in their efforts to resolve the issue. On my end, I've sent them most of the images I'm posting here and more along with other supporting data, including contrast curves and tone charts with the understanding from them that the problem is real and acknowledged (sort of) and that at some point it will hopefully be resolved with appropriate attention in the firmware. In the meantime, I've been waiting all winter to report back to them with video results of what would happen on camera in extremely bright conditions on a sunny day after a typical New England heavy snowfall but for the first time in memory this year, we hardly got any snow at all. Now it is mid March and spring is on the way and major snowfall doesn't appear likely, so I guess it is finally time to go public with all of this, prompted by @Feitelijk's post and periodic similar complaints and comments by others.

The SG9665GC is in most ways a terrific, well built, capable and highly reliable camera with a lot going for it. In most ways, it deserves its reputation and popularity with the exception of what I perceive as this major flaw (and a few other less consequential quibbles I plan to discuss later in this thread).

The thing that has mystified me though is how could I possibly be the only one to experience this to this degree on three different SG9665GC units and be the only one reporting it? While I have some theories about why that is, I want to make clear that my purpose in posting this thread is not to complain but to publicly discuss and analyze. One of my main goals is to hear from other SG9665GC owners regarding their camera's ability to handle bright high contrast/high dynamic range situations. It is similar to what I'm presenting here? Is it worse, or better, or not so bad, or not a problem at all?

Little by little, there have been hints, posts, videos and some screen shots from other members that suggest this problem but for some reason it has not gotten the attention I might have expected. As I said earlier, it was @Feitelijk's post (and several others I may bring into the discussion) that finally compelled me to stop procrastinating and put this presentation together.

Beginning all the way back last August I began making simultaneous tests between the SG9665GC and other cameras in an attempt to analyze the issue and as a way to demonstrate to @jokiin and @Pier28 what I was experiencing. All cameras were set to their default exposure settings. No CPL filters were used in these tests. In all cases, as previously stated, the differences were dramatic.

Here is a simultaneous comparison between the GT680W and the SG9665GC transitioning from under a tree canopy to bright sunlight.



Here I simultaneously compare the SG9665GC and the Mobius.




Here, I compare the SG9665GC with the mini-0806.




Here is another example comparison between the mini-0806 and the SG9665GC. Note the motion blur difference on the blue car between the SG and the 0806. Both cams were shooting at 30fps. The blue car appears elongated on the SG compared with the 0806 suggesting a slower shutter speed on the SG which might account for or be a contributing factor in the results. You'll note also that the mountain in the far distance out on the road seen on the 0806 image has completely disappeared into the glare in the SG image.




Another simultaneous GT680W and SG9665GC comparison.




Here is a more recent video example from December, 2015. This is a different unit than the one used for the above screen captures last Summer and Fall. The firmware is different than the other camera, I believe its is the November release as I recall. My vehicle is now sporting a snazzy new very dark black dash mat which performs a killer job cutting down on windshield reflections (as does the SG CPL) but has no effect on the glare and dynamic range capture failure.

Note how the footage starts out fairly dark and almost underexposed and then falls apart later in the video. It is important to watch this video carefully and wait until exactly the 2:00 minute mark to see what happens.

Here is another sample.

So there you have it for now. I will reserve a post to add more material below as I've used up my upload allotment of ten images in this post but this should explain the problem with the SG9665GC. As I said earlier in this post, there are some other unrelated "grievances" I have with the SG but they are far less serious and more from a functionality standpoint than a performance flaw but perhaps I will post about those unrelated issues bellow at a later date. Indeed, in the meantime, I am very curious to hear other SG owner's experiences with exposure, glare and dynamic range.

 

[Dashmellow]

Two more GT680W/SG9665GC comparison images.

 

[jokiin]

if anyone else has any sample footage of these types of situations please share the videos, these scenes are very hard to duplicate, real world footage is best for this so any videos anyone may have that can be uploaded to a file host (need raw files to work with please) will be very helpful, the more sample data we have for the engineer to work with the better

any side by side footage is particularly useful if anyone has a second camera that they can share same data from is very helpful, screenshots can help pinpoint what we need to look at but really need the videos for analysis by the engineers

 

[reverend]

I don't recall seeing anything like that - is this just on V2 or also V1?

It's not the AE mask getting confused by the large black bonnet and overexposing is it? It's easy to visualise it on Ambarella but I've never seen them on Novatek cameras.

I've seen the IMX322 on many cameras clip to white when you're driving into sunlight but not like the clips here! I usually ignore the 70/30 or 60/40 rule with the IMX322 and just go 50/50 or even higher as that helped me work around a specific issue I had with the X2 in the past where it would overexpose stuff and use a slow exposure time.

 

[Dashmellow]

I don't recall seeing anything like that - is this just on V2 or also V1?

It's not the AE mask getting confused by the large black bonnet and overexposing is it?

I've seen the IMX322 on many cameras clip to white when you're driving into sunlight but not like the clips here! I usually ignore the 70/30 or 60/40 rule with the IMX322 and just go 50/50 or even higher as that helped me work around a specific issue I had with the X2 in the past where it would overexpose stuff and use a slow exposure time.

One of the reasons for posting the comparisons is to demonstrate that the dark navy blue bonnet doesn't cause the problem for other cameras as seen on the SG. The screen shots are of three different SG hardware units of different vintages with different firmwares. (Waiting for the forthcoming release to test and see what happens.)

 

[jokiin]

next release won't have any AE adjustments, there's some other bugfixes happening first, AE is next month (IQ adjustments are done by a different engineer), any footage I can collect before then is very helpful for this

 

[wozzzzza]

cant say I have had any issues like this that I recall. but will take notice.

 

[DT MI]

I've had instances that have come close to what you're experiencing but only when exiting a tunnel or long overpass into a sunlit area. I do experience the sky being washed out to near pure white but that doesn't bother me (and to me is a bit expected) given the low light capabilities of the SG.

What is interesting to me based on my photography experience is the motion blur demonstrated in the 806 comparison. This tells me the exposure period (shutter speed in SLR terms) is much longer than needed. This would account for both the motion blur and over-exposure of the image.

A quick look at some of my readily available videos came up with this as a typical 'bad' exposure not related to exiting a tunnel, etc. and is normal when driving east in the morning. This was a 'grey sky' morning, 'blue sky' days tend to be less washed out.



Rummaging around some of my files and found this - V1 camera with CPL.

 

[Dashmellow]

I've had instances that have come close to what you're experiencing but only when exiting a tunnel or long overpass into a sunlit area. I do experience the sky being washed out to near pure white but that doesn't bother me (and to me is a bit expected) given the low light capabilities of the SG.

What is interesting to me based on my photography experience is the motion blur demonstrated in the 806 comparison. This tells me the exposure period (shutter speed in SLR terms) is much longer than needed. This would account for both the motion blur and over-exposure of the image.

A quick look at some of my readily available videos came up with this as a typical 'bad' exposure not related to exiting a tunnel, etc. and is normal when driving east in the morning. This was a 'grey sky' morning, 'blue sky' days tend to be less washed out.

View attachment 21461

Rummaging around some of my files and found this - V1 camera with CPL.

Those don't look bad at all.

I should explain that my camera often performs quite well. It is only under certain brightness or contrast situations where it is as if its ability to control the upper third of the tonal range seems to get pushed over the edge.

Here the camera is performing well in challenging lighting at dusk.


Under flatter lighting everything looks fine.


Other times, in very bright or high contrast conditions everything seems to fall off the edge, like in this example I posted last week in another thread. The entire drive up the road looks about like this...no tunnels or much of a tree canopy most of the way.


The above examples are from the unit shipped to me in December, (my third.)

Here is an early example from the first camera that I received at the beginning of last April, of course with older firmware. (and hardware)

 

[Dashmellow]

There are other times when the camera fails to perform in odd ways, always when it comes to retaining detail in highlights and the upper 25 or 30 percent of the tonal range. In this example, under somewhat overcast skies and flat lighting everything looks perfectly normal except that the silver car out in front of me has lost all detail in blown out highlights. The SG9665GC is the only camera I've had experience with that does this. This one is a good example of how the problem can manifest without bright sun or emerging from shadows like coming out of a tunnel or from under a canopy of trees.

(This was from camera number two of the three samples I've had to work with.)

 

[kamkar]

Sun gods have forsaken me yesterday and today, will do my best to get some simmilar footage up ASAP.

The silver gray car in the pic above can allso be seen on my licenceplate capture video from the highway.
It is a little further avay, but still its hard to see any shape to it beside the 2 tail lights, and even those seem to be blurred out too
https://dashcamtalk.com/forum/threa...ate-capture-high-speed-two-way-traffic.17543/

There is even a silver car in front of me in the other video in same thread, but that time around in more modest lighting conditions it is more clear to see what it is, you can see the bend in the rear hatch and allso the shape / curves of the bumper.

 

[Dashmellow]

Sun gods have forsaken me yesterday and today, will do my best to get some simmilar footage up ASAP.

The silver gray car in the pic above can allso be seen on my licenceplate capture video from the highway.
It is a little further avay, but still its hard to see any shape to it beside the 2 tail lights, and even those seem to be blurred out too
https://dashcamtalk.com/forum/threa...ate-capture-high-speed-two-way-traffic.17543/

There is even a silver car in front of me in the other video in same thread, but that time around in more modest lighting conditions it is more clear to see what it is, you can see the bend in the rear hatch and allso the shape / curves of the bumper.

That video and every other image in that thread for that matter seems far superior than anything I've personally experienced with the SG9665GC.

 

[arcticfire]

Why not try adjusting the camera so it's pointing up to the sky and eliminate the bonnet?

 

[Feitelijk]

That video and every other image in that thread for that matter seems far superior than anything I've personally experienced with the SG9665GC.

Agreed!

 

[Dashmellow]

Why not try adjusting the camera so it's pointing up to the sky and eliminate the bonnet?

Trust that someone with six years of dash cam experience has explored various exposure options after a year of dealing with this. The problem is not exposure, per se, it is a contrast/dynamic range/tonal range issue.

It sounds from your suggestion that perhaps you haven't watched the videos I've provided, such as the one where the footage starts out literally too dark and underexposed and ends up completely blown out by the end. Tilting the camera would not fix that nor would it be wise for all the other footage I capture where the image exposure is perfectly fine. Tilting the camera up would also not do anything to fix the silver car out on the highway with excessively blown out detail but otherwise overall good image exposure either.

Again, as I've been trying to point out here, no other camera manifests this problem under identical circumstances (or aiming).

Here are screen shots from the beginning and end of the aforementioned video.


Another reason for not eliminating the hood (bonnet) from the image is that I would lose important coverage on either side of my vehicle.

 

[Dashmellow]

The camera is capable of really excellent results when aimed in what has come to be understood as the proper ratio (65/35) of sky/hood when presented with the right lighting conditions. What seems to happen is that certain conditions push the camera's abilities over a threshold where it suddenly can't handle the tonal range/dynamic range/brightness it is presented with.

 

[kamkar]

Funny thing, i allways been feeling my SG9665GC is a bit,,,,Mmmmm "mellow" compared to footage other have made with the same camera.
At first i blamed it on me meeing used to look at the footage off my old Lukas camera, that compared to the SG camera have a artificial sharpness like feeling to the footage.
Anyway in respect to the x camera we allso see the same, some ppl cant seem to get the same out of them as other ppl, even though they had the camera replaced one or more times.
Quite strange if you ask me.

I am not driving near enuff to really go into if there is some lighting circumstances where the 9665GC perform better than other pretty much simmilar conditions, damm thing beeing poor, i can only afford to drive a mentionable drive every 3 days or so, and thats just 2 X 30 km or so i drive.
Thost ppl i am working with in regard to my helth better get ther gear in order and find me a part time job i am able to handle.

I can do better in reviewing my footage off the 9665 and other cameras, and i will start to do that, cuz as it is now i cant blame me not dooing that on not having the time for it, i have a lot of free time here, i just spend it in very unproductive ways.

Tho if i get into some money i can splash around i better spend the first lot of them at the dentist, been 4 years since i visited that guy and i am starting to feel that.

 

[kamkar]

My hand have just been forced ( again ) my little sister had a accident at work, so i have to go to her house tomorrow to help with the dogs.

Nothing that bad she just fell on a gangway over the machines and twisted her foot.
So i get a chance to capture some footage tomorrow, but the chance for sun is moderate at best but lets see what i get.

 

[Nigel]

Trust that someone with six years of dash cam experience has explored various exposure options after a year of dealing with this. The problem is not exposure, per se, it is a contrast/dynamic range/tonal range issue.

I understand your point, but clearly the large amount of black filling most of the area normally used for calculating the exposure is having an effect and is having more effect at the times when the contrast is highest, and is made more complicated by the fact that it is reflective and so sometimes contains the bright sky instead of black. I think it would be at least interesting to try it on spot metering for a while if that option exists on this camera, it may help with diagnosing the problem even if it doesn't actually help, the area normally used for spot metering doesn't contain any of the black.

 

[arcticfire]

Trust that someone with six years of dash cam experience has explored various exposure options after a year of dealing with this. The problem is not exposure, per se, it is a contrast/dynamic range/tonal range issue.

It sounds from your suggestion that perhaps you haven't watched the videos I've provided, such as the one where the footage starts out literally too dark and underexposed and ends up completely blown out by the end. Tilting the camera would not fix that nor would it be wise for all the other footage I capture where the image exposure is perfectly fine. Tilting the camera up would also not do anything to fix the silver car out on the highway with excessively blown out detail but otherwise overall good image exposure either.

Again, as I've been trying to point out here, no other camera manifests this problem under identical circumstances (or aiming).

Here are screen shots from the beginning and end of the aforementioned video.
View attachment 21471 View attachment 21474

Another reason for not eliminating the hood (bonnet) from the image is that I would lose important coverage on either side of my vehicle.

It was only a suggestion for testing purposes.