TeriTerryTarry

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Dash Cam
Several action cams
I'm considering a camera with the following specs per the manufacturer:

Image Sensor: 16.0MP full HD CMOS, manufacturer not specified
Chipset: Ambarella A7LS75
Video resolution: Full HD 1080P at 60fps/30fps, 720P at 120fps/60fps/30fps, 848 x 480 at 240fps/120fps/60fps/30fps
Image Resolution: 14M (4608x2592), 14M (4608×3072), 16M (4608 x 3456)


Per the specs these appear to be pretty good numbers for an inexpensive action cam. According to the Ambarella A7LS Product Brief http://www.ambarella.com/uploads/docs/A7LS-Brief-121713.pdf the chipset should be capable of handling the image sensor with no problems. However, does any of this actually tell me the native resolution, image size or frame rate? Although the chipset seems able to handle the image sensor, wouldn't it also depend on how the manufacturer has programmed the chipset? And does any of this tell me the frames-per-second capability without frame doubling?

Even if the camera is capable of 1080p resolution, 16MP images and 60fps without frame doubling, doesn't the output of the sensor affect quality? Isn't the sensor the thing that converts light waves into ones and zeros so its ability to do this accurately affects image quality?

I sometimes see that bitrates have a bearing on video quality, generally the higher the better. Is the bitrate a function of the sensor or chipset or are there other internal components that would affect this?


Another question would be the lens. While I presume it generally affects the image quality does it also limit any other parameters? For example, even though an image sensor is capable of 16MP, does the lens configuration actually cast an image size that takes advantage of the full surface area of the sensor?

Does image stabilization limit resolution or frame rates? Beyond its stabilization function, does it affect video or still image quality in other ways?

There's also the question of the transfer of files to devices outside the camera itself. The camera could have all the right specs internally but we shoot videos and pics to view on smart devices, TV's and computer monitors. Output must comply with industry standards in order to be compatible with other devices but what about the quality of the output? Do internal components besides the chipset affect the quality of the output? For example, what about the Wi-Fi transmitter? Any others?

If you pass this quiz you get an A+ grade!!!
 
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They dont say what exact CMOS sendor brand / model / type is used.
Do you have a link to the website with the product ?
 
One further question I meant to ask is about batteries. A feature of AC electricity is power quality consisting of a number of parameters. I don't know if there is some similar measurement for the DC power of the battery that might thus affect the operation of the camera.
 
They dont say what exact CMOS sendor brand / model / type is used.
Do you have a link to the website with the product ?
The specifications actually come from the seller's website. I don't see this model on the manufacturer's website. http://www.boscam.cn/
 
No, I actually had to contact them for this piece of info :)
 
Ah, thank you. Now when you say "them", do you mean Boscam or GearBest?
 
Okay, that's great Pavle. Thanks very much. :)
 
Pavle is pretty much on top of things like that :cool:
My own intrests in dashcams and action cameras dont reach that far, i just cover the bases and then lean on the nerds for full enlightenment.
 
You're quite right that Pavle is very much on top of these things. I'm still a wet-behind-the-ears newbie so I pretty much lean on everybody for everything but I'm trying to take my first baby steps! My questions arise from my experience buying an SJCam SJ4000 Wi-Fi. They claimed an image size of 12 MP but that was only achieved by interpolation. They also claimed 720p at 60fps but didn't explain that was double frame rate. I'm just an average consumer with no expertise in optics, electronics or cameras and no particular knowledge of photography beyond enjoying it. But now my curiosity has been piqued, hence the questions here and many more in the SJ4000 thread.

Cheers :)
 
They also claimed 720p at 60fps but didn't explain that was double frame rate.
If you had watched Techmoan's videos you would know that and many other things about the SJ4000 and a whole lot of other action/dash cameras as well. ;)
Every beginner should watch all his videos before deciding what to buy.
 
If you had watched Techmoan's videos you would know that and many other things about the SJ4000 and a whole lot of other action/dash cameras as well. ;)
Every beginner should watch all his videos before deciding what to buy.

SJCAM would release 6 new models by the time you finished watching all his videos then you'd have to go back and do it all again ;)
 
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SJCAM would release 6 new models by the time you finished watching all his videos than you'd have to go back and do it all again ;)
And ROGA World will release 7 so they can be ahead of the "most new cameras released" game.
No danger of that happening. Techmoan doesn't review every single model that comes out. That's why his videos are so useful. ;)
 
If you had watched Techmoan's videos you would know that and many other things about the SJ4000 and a whole lot of other action/dash cameras as well. ;)
Every beginner should watch all his videos before deciding what to buy.

You're right but not every average consumer is going to take the time to look at every Techmoan action cam video or even know that they exist. Furthermore there is no excuse for manufacturers' failure to fully disclose information like interpolation and frame doubling when the rest of the specs are listed. It's deceptive because one reasonably assumes that a full listing of specifications is in fact a full listing without errors, omissions or exceptions.
 
You're right but not every average consumer is going to take the time to look at every Techmoan action cam video or even know that they exist. Furthermore there is no excuse for manufacturers' failure to fully disclose information like interpolation and frame doubling when the rest of the specs are listed. It's deceptive because one reasonably assumes that a full listing of specifications is in fact a full listing without errors, omissions or exceptions.

This is common marketing tactics many vendors / manufacturers use in order just "to get rid of their supa-dupa product" and take your money.
 
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