Rear Dashcam Question

[Hamish2015]

For those of you who have one fitted is the lens / image affected at all by the heated windscreen wiring? Just about to fit mine and wondering if the lens might try and focus on the screen rather than the road. My UX has a wire in the middle that runs vertically down the screen so I may need to offset a little probably to the O\S. I'm also hoping that the wiring won't be damaged by the sticky pad used to attach the camera if it needs to be removed.  

[LenT]

20 hours ago, Hamish2015 said:

For those of you who have one fitted is the lens / image affected at all by the heated windscreen wiring? Just about to fit mine and wondering if the lens might try and focus on the screen rather than the road. My UX has a wire in the middle that runs vertically down the screen so I may need to offset a little probably to the O\S. I'm also hoping that the wiring won't be damaged by the sticky pad used to attach the camera if it needs to be removed.  

I’ve never been aware of the heating/aerial elements in the rear screen being visible in my dashcam recordings.  I would think the focal length of the lens is far too long for that!  But if you want reassurance just fit the camera temporarily with scotch tape while stationary as a test.

Similarly, all my cameras have been fitted by using 3M pads.  In extreme heat situations what has (rarely) happened is that the camera has fallen off with the pad - which simply pressed back on.  It’s usually recommended that the screen is carefully cleaned with, say, an isopropyl alcohol wipe, before fixing to the glass.  I think that it’s generally advised to avoid the dotted areas on front screens because the dots reduce the contact area.  Also it’s usually sensible to wipe screens parallel to any visible wires, rather than across them.

I’ve never had cause to remove a pad, but if I had to do so I would first use dental floss to saw between the pad and the mount.  This is unlikely to affect any screen-mounted wires.  I would then use the usual solvents to soften and remove the remaining adhesive and pad.  For example; lighter fuel, isopropyl alcohol, acetone, nail varnish remover - even turps will soften it so that any residue can normally be rolled off the glass.

Finally, if yours is a new camera kit, it’s possible that all these points may be covered in the fitting instructions.  Of course it may be that you’re fitting a system previously in another car, and such instructions are now long gone!

[Herbie]

Exactly what Len says above.

Here's where mine is located:

[Hamish2015]

Thanks for the replies Herbie / Len, I fitted it today and the pad and lens handily fit between the HRC elements. The view is unobstructed and the image very clear so I had no need to worry. 

[LenT]

30 minutes ago, Hamish2015 said:

Thanks for the replies Herbie / Len, I fitted it today and the pad and lens handily fit between the HRC elements. The view is unobstructed and the image very clear so I had no need to worry. 

Excellent news, James.  In my book, every extra dashcam makes us all a little safer.

Now I don’t know if you’ve had one before, so forgive me if this is stating the obvious.  But it’s important to regularly reformat the microSD Card, rather than let it fill up and overwrite the old files.  The constant overwriting can introduce errors and, for example, make the files unreadable or affect functionality.

Also, although you don’t name the camera, you may well find that ensuring it’s powered so that it’ll work in Parking Mode could prove to be a very important benefit.

[Herbie]

1 hour ago, LenT said:

Now I don’t know if you’ve had one before, so forgive me if this is stating the obvious.  But it’s important to regularly reformat the microSD Card, rather than let it fill up and overwrite the old files.  The constant overwriting can introduce errors and, for example, make the files unreadable or affect functionality.

I'm not sure I agree with that Len.

When any drive or card is formatted the existing files are not deleted or erased in any way. All that happens is that the device (camera, computer, tablet or whatever) loses its map of where the files are located.

Think of it like ripping out the 'Table of Contents' from a book; the pages are still there but you don't know where to find any given chapter. Formatting just removes the table of contents from the drive. All the existing files are still there and still intact* but the device doesn't know where they are and can't see them, so it thinks the drive is empty and the space is available to write new files into.

So, format the card or leave it alone, it makes no difference; the end result is still constant overwriting; any errors or change in functionality are probably caused by other factors.

*This is how and why data can be recovered from faulty, corrupt or damaged drives/cards.

[Hamish2015]

Thanks guy’s, I have a Nextbase 622GW, the manual says the files will be automatically deleted but also suggests that to maintain stable performance the card should be regularly formatted. It’s my first dashcam so I’m still learning all of the features and settings, I’ve added the text below directly from the manual. 

“Format SD Card
Format the inserted SD card. This will delete all content. If the format is unsuccessful, a message will appear on the display;
“Format failed, please try another SD Card (U3, 128 GB Max).”
Note: For stable performance, it is recommended that you format the SD card every 2-3 weeks. You should only do this AFTER you've downloaded any files from the card that you may
want to keep.”

[Vlady]

My card came with the adaptor that fits into my laptop, so all I do is take the card out of the dash cam and insert it into the adapter to view or to delete files and usually I format the card after that anyway. This way it has less stress on the 3M pad if I was removing the whole camera every time.

I do it every 3-4 weeks by they way. 

I got Nextbase 622GW installed about 3 weeks ago, just a frontal camera. 

[Herbie]

55 minutes ago, Hamish2015 said:

Note: For stable performance, it is recommended that you format the SD card every 2-3 weeks.

 

9 minutes ago, Vlady said:

I do it every 3-4 weeks by they way. 

Nextbase always say "For best results we recommend the Nextbase memory card."

Viofo always say "For best results we recommend the Viofo memory card."

And so on.

The sad thing is that we already know these manufacturers don't actually make their own memory cards anyway, they just buy them in and stick their own label on them.

I'm not saying that my way is good, their way is bad, or even that there's a right or wrong way. Just saying that manufacturers sometimes do things for their own reasons which are not always obvious. The description I gave above really is the way that formatting works, so I can't see any difference in achieving the end goal. Either way overwrites old files with new ones and either way seems to work fine. I haven't formatted my card since installing the camera back in March when we bought the car and it's never missed a beat.

[LenT]

On 1/21/2022 at 12:08 AM, Herbie said:

I'm not sure I agree with that Len.

When any drive or card is formatted the existing files are not deleted or erased in any way. All that happens is that the device (camera, computer, tablet or whatever) loses its map of where the files are located.

Think of it like ripping out the 'Table of Contents' from a book; the pages are still there but you don't know where to find any given chapter. Formatting just removes the table of contents from the drive. All the existing files are still there and still intact* but the device doesn't know where they are and can't see them, so it thinks the drive is empty and the space is available to write new files into.

So, format the card or leave it alone, it makes no difference; the end result is still constant overwriting; any errors or change in functionality are probably caused by other factors.

*This is how and why data can be recovered from faulty, corrupt or damaged drives/cards.

Thanks Herbs for this comment. Let me establish that I am still astonished that a solid state device the size of a finger nail can store even one full length movie – and for years apparently. So I’m sure you know how it works better than I do. In fact, probably almost everyone does!

So, as far as regular formatting goes, my explanation may sound a bit lame….namely, that’s what Blackvue recommends! Actually, they state every month, although as has already been noted, every 2-3 weeks is also mentioned elsewhere.

My slight query regarding that is why is it calculated in calendar time rather than, say, running time? Or is flash memory affected by age as much as usage?

Mostly, reformatting seems to be analogous to ‘wiping the slate clean’ so that fresh files can be written to the memory. I appreciate that you say that the original files are not deleted, but I have two formatting apps and when I use them I have to negotiate stern warnings to back up important files because everything will be deleted.

Frankly, I’ve never felt that hoping I can use some recovery operation is worth the risk, so I take it seriously.

For example, here’s a comment by a professional photographer explaining why he downloads and reformats his SD Card after every shoot:

‘When an SD card is formatted, all the data is wiped clean and replaced with a new folder system for your camera or device to write on. You could think of it as an easy way to start fresh with the card. No files, no space taken up, just a blank space for you to fill with data. At some point along the way, you’ll likely run into some issues with the SD card, and formatting it is usually the best problem solver.

Before I get into the specifics, remember that formatting your SD card will erase all its data. Before you pull the trigger on formatting your card, make sure all the files have been safely backed up.’  (Original emphasis retained).

Even if the memory itself isn’t literally blank, then I presume that what happens is that the new files overwrite the old files. As the Card reaches its capacity, so the frequency of overwriting increases.

As I understand it (the extent to which has already been established) it is this very process of overwriting - and reading - in effect the constant transfer of data, which provides the opportunity for writing errors to be introduced. Over time these accumulate and create ‘bad blocks’. Undoubtedly a bad thing!

On the one occasion when I had to rely on my SD Card to provide evidence when my Accord was written off, I was grateful that I could access and supply those videos without having to even consider the possibility that they might be inaccessible for any reason.

 

[Herbie]

A lot of good points there Len - I'll do my best 

I'm not being nasty or derogatory to anyone in any way, but instructions have to be written for the lowest common denominator and they are aimed at the 'ordinary Joe Bloggs'.

With that in mind, when you use your formatting software and it gives you dire warnings to back up important files, and also the warnings from the professional photographer that "formatting your SD card will erase all its data", they are talking in 'Joe Bloggs' terms. To all intents and purposes, as far as 'Joe Bloggs' is concerned, yes, all that data will be erased - but only because 'Joe Bloggs' doesn't have the knowledge or the software to make them visible again.

They are still there and they can easily be recovered after a format if you have the software and the knowledge to use it, but to Joe Bloggs those files have gone forever.

It's only because of my (initially) hobby interest in computers and later on doing 10-12 years as a self-employed computer technician doing repairs and bespoke builds that I know this.

Quite often I would have to condemn a client's computer as being beyond economic repair and after transferring their data to a new one, I would have to use specialist software (such as Active KillDisk or DBAN for example) to carry out secure deletion to make sure that no one could ever recover any of that client's data. There are a couple of different industry standards for secure deletion but one of them is the American DoD (Department of Defence) 7-pass method, where the software writes zeros to the entire disk on Pass 1 then writes ones to the entire disk on Pass 2 and so on.

If a simple format really did erase all the data without possibility of recovery then there would be no need for secure deletion programs like the above.

Good question about the frequency of the recommended format Len; I have no idea why it's calendar time and not run time - I'll see if I can find out.

3 hours ago, LenT said:

Even if the memory itself isn’t literally blank, then I presume that what happens is that the new files overwrite the old files. As the Card reaches its capacity, so the frequency of overwriting increases.

As I understand it (the extent to which has already been established) it is this very process of overwriting - and reading - in effect the constant transfer of data, which provides the opportunity for writing errors to be introduced. Over time these accumulate and create ‘bad blocks’. Undoubtedly a bad thing!

Basically, yes, that's correct.

The camera records on the card until it's full and then it goes back to the beginning and starts to record over the existing files, ad infinitum, with the oldest files being overwritten first. I suppose, just like everything else, age begins to take its toll on the card eventually.

[LenT]

49 minutes ago, Herbie said:

I'm not being nasty or derogatory to anyone in any way, but instructions have to be written for the lowest common denominator and they are aimed at the 'ordinary Joe Bloggs'.

To slightly paraphrase H L Mencken; No-one ever lost money underestimating the intelligence of the Public.