Jomise F2S 4K Dual Lens

TechTronic9000

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The Jomise F2S is a dual camera car DVR with that is able to record up to 4K and an extra 1080p stream. The camera comes full featured with large IPS screen, shock sensor, motion detection, GPS speed logger, Sony image sensor and large lens aperture.

I had a few things that I was following in getting a new dash camera.
- A better support as I take the camera off so this one has very ingenious magnetic system, no more bent pins, rattle & failed clips.
- 4K recording which this camera provides along with very crisp image quality that makes.
- Decent rear camera which again this system provides.
- Last but not least GPS was also necessarily for logging the trip and speed.

PROS:
- Very good image quality in all light situations such as night time, clouds, rain and daylight.
- Lots of options to adjust including several available resolutions.
- Magnetic mount so no more rattle and broken connectors.
- Good rear camera that works OK even though my rear window is tinted black.
- Good working WiFi app with lots of functions.
- Fast locking GPS logger.

CONS:
- Only one set of adhesive 3M pads, so if you remove it you need to buy new pads.
- Frame rate is lower in 4K+1080p but still creates very sharp image in which you can observe important details such as number plates.


 

Mtz

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Is it a real 4K dash camera or it is only 2K and the 4K is interpolated?

enjoy,
Mtz
 
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TechTronic9000

TechTronic9000

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It does genuine 4K HVEC H.265.
 

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Mtz

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What chipset and what CMOS does it have? That properties are not a proof that camera is recording true 4K.
 
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kamkar

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Listing on amazon in the uk say it have a IMX335, so if thats true it are not true 4K

"The 2.45-inch IPS screen drive recorder uses Sony335 lens to achieve 4k ultra-high image quality."
 

Mtz

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I was almost sure, but I didn't saw any word about CMOS. Somebody should tell them the Sony 335 is a CMOS, not a lens.

enjoy,
Mtz
 
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TechTronic9000

TechTronic9000

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Listing on amazon in the uk say it have a IMX335, so if thats true it are not true 4K

"The 2.45-inch IPS screen drive recorder uses Sony335 lens to achieve 4k ultra-high image quality."

I've bought mine from amazon.com, they don't specify the sensor there.

As for fake 4k it's discussable, you can see a really big difference between the 2K and 4K in the image details / quality / sharpness, especially if you do a frame grab and zoom-crop.
 

Mtz

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When chipset or CMOS are not native 4K then it is fake 4K and the 4K resolution is done by software upscaling. They are taking images with few pixels and adding double fake pixels to obtain the 4K resolution. So for this dashcamera half of the pixels are interpolated!
I hope you remember some previous action cameras (even SJCam) which had poor quality at 4K, some of them offered just 15FPS because the chipset cannot handle 30FPS. From that moment the SJCam was out from my recommendations and as we can see after just 2 years SJCam is not doing so well as before, they don't needed at all to create fake 4K dashcams, the buyers doesn't like cheaters.

There is no problem to sell such cameras, but it is correct they to be informed about real specifications. Like on action cameras, when I see a 4K dash camera under $100 I start asking myself if it is 4K real or not.

A manufacturer can be correct if it is advertising the camera as a 2K dashcam which is the real resolution, but is offering as a bonus the 4K resolution and write there that it is an interpolated 4K. I saw such descriptions.
But if a manufacturer is spending less money to a cheaper 2K CMOS instead of paying more money to a more expensive 4K CMOS and then it is putting into the title of the camera that is a 4K dashcamera, then it is not correct for the buyers to be cheated.
This can happen on Aliexpress or on ebay, but is not correct to happen on dashcamtalk because here people come to be correct informed about a product and this is giving value to this forum.

In this year will be more and more 4K dashcameras, real or fake 4K. Their biggest problem will be heat.

I've bought mine from amazon.com, they don't specify the sensor there.
Of course they don't want to write real specifications because some people know the difference between 2K and 4K just by looking at the CMOS type.

enjoy,
Mtz

PS: sorry, but I just hate manufacturers which are lying just to take the money from people. It is like stealing.
 
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SawMaster

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When chipset or CMOS are not native 4K then it is fake 4K and the 4K resolution is done by software upscaling.

Agreed, but cam manufacturers know that the average buyer does not understand this, so many of them will claim 4K for advertising purposes. The issue has long existed even back to when 1080 came along, but at least then you would sometimes see "1080i" or "1080p" so you could tell the difference if you knew what the letter after 1080 meant. That didn't always happen though, and most cams were just listed as "1080" so you had to know something about cams to know what you were getting.

In communication with some cam manufacturers, they have told me that they considered interpolated resolutions to be at the higher standard of the naming convention, and I have had to explain why this was wrong. Some listened, some did not.

On the use of the word "lens" being 4K, when we know it's the sensor, that seems to be from variations in the English language. I've seen "lens" used to describe the glass lens, the sensor and lens assembly, and even a whole rear cam had been spoken of as being a "lens". They understand what is meant and we do too, but the average buyer may be confused by this so it's best to use words properly so that everyone understands. "American English" is my native language, but I have a good understanding of the English as spoken in the UK and Australia. There is some more variation with what is spoken in Hong Kong, and that seems to be the English variation cam manufacturers in China know and use.

One cam manufacturer sometimes asks me to "proofread" their English language ads and recommend changes in spelling and wording. I am happy to provide this service for free to any cam manufacturer. I hope others here will do similar for the ads in other languages which I do not know. This helps ensure accuracy in advertising and makes for a clearer understanding by everyone. My suggestions are not always taken but at least I do try which is all I can do.

Phil
 

Mtz

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I know you have big experience regarding dashcams.
Also Techtronic is making many reviews but for many products, I am a Subscriber of his Youtube channel and I like how is he understating the things, how they are working. I watched many videos made by him but just very few are about dashcams.
With this camera he doesn't received all info, the Jomise is not a correct manufacturer like we are expecting to be on this reputable forum. I am sure if you received this dashcam you could tell to the people that is a 2K dashcam not a 4K dashcam because you have a lot of experience.

enjoy,
Mtz
 
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SawMaster

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I don't have the level of experience many others here do, but I do know a bit and I like to learn :)

Phil
 
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TechTronic9000

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OK, good and bad news :)

Good news was that the seller responded to my technical inquire and gave me the exact specs:
Chipset is NTK96670
Image sensor is Sony Starvis IMX335

So the bad news is that we can conclude this is "fake 4k', so true genuine/native resolution is Quad HD / 2K, while the 4K is an upscale.

Still something interesting is happening with this model as the "4K" has noticeable better details than lesser resolutions. Will try to do some frame grabs of the same image with 1080p/2K/4K and crop zoom them here.
 

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Still something interesting is happening with this model as the "4K" has noticeable better details than lesser resolutions.
It is always easy to damage the quality of the 2K recording so that the 4K looks fantastic and thus must be real!

Maybe the bitrate is higher on the 4K so that it is actually storing more detail? Note that the bits per frame is important, and with a lower framerate in 4K, even if the 4K is the same bitrate as the 2K, it has more bits per frame so can store more detail per frame.

Maybe the sharpening is destroying more detail on the 2K than 4K?

4K should have twice the detail of 2K, but it can be hard to tell because just comparing horizontal resolution (1D instead of 2D) the difference is only 1.4x, it is not an obvious 2 pixels to 1. However if you put a real 4K camera next to a 2K sensor 4K camera and try to read a stationary number plate at distance, the 2x detail becomes pretty obvious, the real 4K can clearly read plates at a greater distance.

The IMX335 is a good sensor for a dashcam, one of the best, just because it is fake 4K does not mean that it is a bad dashcam. It can not have real 4K detail though, only half real 4K detail.
 

SawMaster

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Far more to it than any one aspect. It's the results of everything together than matters most.

In one cam I've tested the vid detail at 2K is better than two other recent cans, one of which in 2K interpolated or upscaled while the other is true 4k o_O

Specs are good to know and can tell you something, but what you see in the actual video tells you everything :cool:

Phil
 
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Mtz

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If the 2K camera have better developed firmware and better lens than the 4K one then it is normal the 2K to have better image.
Most of the people will never understand that not only the specs are important but the lens and firmware development. For example there are 50 2K cameras on the market. Why only 5 of them have great image if all have same specs.?
So the bad news is that we can conclude this is "fake 4k', so true genuine/native resolution is Quad HD / 2K, while the 4K is an upscale.
This is the reason why I stopped myself to accept to make reviews for poor products or for cheating manufacturers.
My time is more precious compared to a greedy manufacturer which is creating poor products with cheating names. I don't want to say that your reviewed camera is garbage but you wasted few hours from your life to review a fake product.
For example you can ask manufacturer how is possible to transmit Full HD digital signal from rear camera to front camera only by using 4 wires. 2 Wires are for powering the rear camera and 2 wires are for video signal. Usually the video signal with 2 wires is analog.
Also you can ask them how will be used the rear camera to record inside car during night if it has no IR LEDs? During night will record nothing inside car. So they added the short cable for nothing.

Of course could be 0 problem for anybody if the name of the camera was Jomise F2S 2K. Your work were for a correct product. The title of this thread on DashCamTalk should be: Jomise F2S 2K Dual Lens. On ebay, aliexpress, facebook can be any title.

I am sure you will not feel OK if you will order a 4K TV and receive a Full HD or 2K TV. I am sure you will return it because you will feel cheated. The same story is with any camera which is advertised as 4K but in reality is 2K. And it is not about 2K or 4K numbers, but a 4K lens is much different to a 2K lens, much more complicate to produce it and much more expensive. So the cheaters are avoiding paying the price for the correct component.

enjoy,
Mtz
 
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