Mobius Maxi F1.5 2.7k

[country_hick]

@Dashmellow Could you start a new thread that explains what we should look for in aftermarket lenses? Although what you said above must make sense I can not take that information to figure out what kinds of lenses might work well or not. I have no idea why f stops and such matter or how to match any lens to a maxi. Although I took most of the yearbook pictures when I was in high school that was years ago and I only used the schools manual 35mm camera with just one lens.

I would assume the starlight lenses should provide a better night image. Why they should be better than stock I have no idea. A basic here is what we look for and why tutorial could help those of us who can only blindly follow another members success to perhaps make some good (or not quite so good as nothing is ever guaranteed) lens choices of our own. I would like better night vision but do not know how to decipher which lenses might provide that potential improvement. Of course, we are all flying blind as mobius does not provide its exact lens source or technical specifications.

@c4rc4mM12 lenses, originally designated “S Mount” have been around since long before dash cams and action cams came into existence. There are many different types of S mount lenses made for a wide range of tasks but these lenses have to be carefully matched in optical performance and lens dimensions to suit the particular camera they will be installed in.

Those of us here on DCT who have devoted a lot of time and effort engaging in actual HANDS ON experience with aftermarket M12 lenses have learned to evaluate the appropriate specifications when we purchase lenses. We look at BFL (back focal length) MBF (mechanical back focus), sometimes FFL (flange focal length.......as with the M12 varifocals) and other significant specifications such as resolving power (Megapixels), Of course, a key consideration in choosing a lens are the actual dimensions of the lens, such as width and barrel length before we make a purchase.

If you go on AliExpress and look at some of the lens offerings you'll see that most vendors not only provide all the necessary information required to make a purchasing decision for your specific needs but that a very helpful technical drawing with all the precise dimensions of the lens is usually on display.
View attachment 41494
Trial and error often plays a huge role when experimenting with M12 lenses. This is how all of us on DCT who have been experimenting with alternative dash cam lenses for several years now have learned what to look for when we evaluate M12 lenses for purchase.

 

[kamkar]

Too me one of the big things to look out for are Back focal length, if this dont mach up fairly good it is when you run into problems not being able to screw the lens deep enough in your socket, or not being able to screw in the kens at all cuz your socket are too low.
The related problem is you dont really know what the back focal length is for the original parts you have, so you will have to leave the lens in place unscrew the socket measure the depth and how the sensor on the PCB relate to that cuz it is most often off the PCB by 2 - 3 mm.
The 8 mm lens i use have actually not seated in much on both the joovuu x cam or the mobius maxi where it is now, the thread are just engaged with a couple of mm or so, not ideal at all but it work.

And of course what sensor size the lens are for, it is no good getting a lens meant for really small sensors and then put it on a substantial larger sensor.

 

[c4rc4m]

Dashmallow slightly personal comments aside, thank you for your feedback.

Some points though:

1. I wasn't "recommending" this lens or "lecturing" that people should use it. No where did I use such terminology. It was a suggestion that someone might like to try it.

2. I came to this lens from a link for megapixel lenses on another site. As there's no lens resolving specs on there I presumed having come from a link for megapixel lenses it was megapixel. Apologies for the suggestion if it turns out to be low resolution and unsuitable for testing

3. I agree there may be physical restraints in fitting a lens to a camera it's not designed for. I believe Harsh has cut down the body of one his Mobii to fit. As I said it was a possible suggestion. I leave it to those who are actively testing to determine fit (beyond selecting M12 of course).

4. My "Obsession" with low distortion high resolution lenses is simple, you can see the difference. Pro photographers don't use consumer lenses for a reason. There is a point of cost vs returns, but as no-one has tested high MP lenses on any of the dashcameras so far, that's still to be determined. It's also a matter of personal opinion where the cost vs performance boundaries lie, dependant on personal resources amongst other reasons.

5. The sharpness of a high resolving power is evident - in a recent thread on the Mobius several people expressed that they were pleasantly surprised by the increase in quality brought about by shifting from a 3mp to a 5mp lens following my suggestions elsewhere on the forum that there was a lot to be gained from a higher resolution lens. It's my experience with lenses generally, you can never be too sharp as the sensor records the detail it is supplied with. However, by virtue of the latter, you can be too soft because of too low a resolution. It's true to say, the limitation is the sensor, but there are gains by down scaling an image over a native resolution image in my experience. As for distortion, distortion is the mother of all evil. Apart from annoying curves at the edges of the picture, those nevertheless being something we can all live with, it often it results in a drop off in sharpness towards the edges, something that is more critical for dashcams as you're often trying to resolve number plates not from cars directly in front but to the side. A rectilinear lens makes a lot of sense in this context.

6. As for my finances, that's a personal subject. Lets just say I earn almost the same as my bills each month (probably a lot lot closer than you can imagine). So buying and experimenting with lenses, that may or may not deliver results, isn't a financial priority for me. I can't afford to have money sat around in discarded lenses.

 

[TonyM]

After some 4 months in play now, is there a general conclusion considering the Maxi (B/f1.5) as a dashcam?

In terms of its ability to capture details of fast-moving objects in both daytime and low light, the Lens B Maxi is my best-performing dashcam, and I prefer it to my Mobius 1 or 2 cameras.
Reliability has been good for me, but I know some owners have experienced random lock-ups. My experience from testing suggests that running the camera at the extreme bitrate option may contribute to such problems with certain cards. I do use the highest bitrate available with 2704x1524@30fps, but I record 1min files and regularly reformat the card. I'm using a Samsung Evo+ U3 64GB card in my Maxi cameras.

My A129 has useful features like GPS and a screen, and with its IXM291 sensor delivers a brighter image in low light, but critically for me the combination of lower bitrate and higher motion blur often result in greater loss of detail than I would like, for the type of driving that I do.

Other dashcam users will have different priorities, so this camera will not suit everyone. The Mobius 1 is still a very good camera with excellent reliability and extensive customisation options.

 

[kamkar]

My Maxi have performed like one would expect, so flawless so far.
Having a mobius maxi in the car are way better than no camera, and also better than some / many cameras out there i would assume.
And it support "turbo" / high bitrates, something i find a little lacking in most other dashcams.

It do miss some features like GPS, but that are not really a must have as speed can be deducted form the footage if it ever get to that, and personally i would take a good dashcam with no GPS over another less good dashcam with GPS any day.

 

[Dashmellow]

@Dashmellow Could you start a new thread that explains what we should look for in aftermarket lenses? Although what you said above must make sense I can not take that information to figure out what kinds of lenses might work well or not. I have no idea why f stops and such matter or how to match any lens to a maxi. Although I took most of the yearbook pictures when I was in high school that was years ago and I only used the schools manual 35mm camera with just one lens.

I would assume the starlight lenses should provide a better night image. Why they should be better than stock I have no idea. A basic here is what we look for and why tutorial could help those of us who can only blindly follow another members success to perhaps make some good (or not quite so good as nothing is ever guaranteed) lens choices of our own. I would like better night vision but do not know how to decipher which lenses might provide that potential improvement. Of course, we are all flying blind as mobius does not provide its exact lens source or technical specifications.

I've given a lot of thought to your request for a lens tutorial thread and while I think it is an interesting idea it's a big topic to tackle that I'm not quite willing or able to take on at the moment. When it comes to explaining subjects like ƒ stops which has a close and inseparable relationship with other factors such as shutter speed and sensor type, for example, you are talking about some of the basic fundamentals of photography beyond just choosing an aftermarket lens to buy and so such a thread request would be almost like teaching an introductory photo course.

I would suggest doing some basic research online so you can learn the fundamentals of lenses, aperture, focal length, FOV, etc. This will provide a foundation to make purchasing decisions for alternative M12 type lenses you may want to explore with your new Mobius Maxi. I would start with a visit to this page on Cambridge in Color, one of my favorite online photography learning resources that I often steer people to when questions like this come up. Also, do some online searching and you'll find a wealth of other learning resources to explore.

Also, please ask any specific questions you may have so that more knowledgeable members can offer answers. In fact, I do agree that this would be better done in a new separate thread rather than here in the Maxi thread and so I have created one that is intended as a general thread where anyone who has something worthwhile to offer about lenses and how they work can do so and anyone who has any questions to ask can do the same.

Aftermarket alternative M12 lenses for your dash or action camera

 

[c4rc4m]

Thanks for the recommendations Harsh / Tony / Kamkar. I recently did overtime at work so I've spent it on one of these as a replacement for the A119. Ordered the B lens given the excellent night results Harsh has been having. I'm a Mobius owner again!

 

[Dashmellow]

@c4rc4m

1. Claiming that you were “suggesting” rather than “recommending” is nothing more than meaningless semantics. “Suggest” is literally in the thesaurus as a synonym for “recommend” Look it up.

2. Reaching a conclusion about the specifications of this 640 x 480 lens based on the internet search terms you used rather than taking the time to actually read the information on the page you landed on is a rather strange logic which is nothing more than a failure to use intelligent evaluation skills or critical thinking. Basically, it's called sloppy research. Even if you thought this to be a “megapixel” lens, why didn't you even bother to find out how many “megapixels” it was rated at or any of the other key characteristics of the lens considering your instance on high megapixel numbers? I'm quite sure most members here who recommend that other members go out and purchase an expensive, allegedly “high end” aftermarket lens for a 2.7K camera only to have it pointed out that it only accommodates a sensor resolution of 640 x 480 pixels would likely say, “Oops, sorry, my bad” and that would be the end of it. With you we get rationalizations and prolixity which has become a strange repeated pattern here as time goes on.

3. I was not talking about modifying a camera to force a lens to fit. I was talking about evaluating the specifications of a lens so you can make an intelligent purchase decision. How amusing that you apparently now intend to “leave it to those who are actively testing to determine fit”. That's a good one coming as it does from an armchair pundit who resides in a castle in the air!

4. Your “obsession' with high end lenses for dash cam seems increasingly pretentious and misguided, especially because it is entirely nothing more than a vicarious fantasy. If you never have any personal experience with aftermarket M12 lenses (or the appropriate cameras) in the real world you will never truly “see the difference” as you claim to have already done.

5. Just because several people reported better results from a 5MP lens vs a 3MP lens tells you practically nothing. There are numerous reasons other than numbers of “megapixels” for different results between two disparate lenses. You could easily have two lenses with the same number of megapixels that will perform differently based on their optical designs, number and configuration of elements, coatings and glass types. It's apple to oranges.

There are so many remarks in this fifth paragraph that are wrong it's hard to know where to begin. You are displaying numerous amateurish misconceptions about how this all works. Your statement that, “you can never be too sharp as the sensor records the detail it is supplied with” (while claiming experience you don't actually have according to what you've previously told us) is patently incorrect. Firstly, the term “Megapixel Lens” is merely a meaningless marketing term introduced by lens manufacturers about 20 years ago after Sony introduced a 2/3” megapixel sensor which started the trend towards low cost megapixel CCD sensors, so now we are all unfortunately stuck with the term. There is no agreed upon quantitative measurement for what a “megapixel lens” is regardless of how many “megapixels” the lens is rated at. The primary quantitative measurement of the resolving power of a lens is based on how small a spot it can resolve based on Line Pairs per millimeter (lp/mm), not “Megapixels”. So if you want to resolve an object or detail of a particular size, the determining factor is the size of the pixel, which in fact is what ultimately determines the resolving power and quality of the lens that is required for digital imaging!

So, a lens needs to be carefully matched with the sensor it is fitted to according to the size and shape (sagittal & meridional) of its pixels in relationship and the overall size of the sensor. Each lp/mm of resolving power needs to match the pixel size with each line pair corresponding to two adjacent pixels. A sensor with smaller pixels requires a higher quality of optics to resolve a single pixel! A specific ‘megapixel’ lens of a given number will NOT perform the same on two cameras with the same resolution if the pixel sizes are different! If you are using a lens that has too many “Megapixels” for the given sensor you will not gain anything and in fact performance can actually be degraded. It is possible that the resolution of a lens is too good. Then something known as Color moiré occurs. Problems occur when the lens “sees more” so to speak than the sensor is capable of. Only clueless amateurs subscribe to the false belief that “More lens megapixels is always better”.

Additionally, the related concept of MTF (modulation transfer function) also plays is a key factor in determining lens quality and resolving power but that is a complex subject for discussion at another time.

So, “Distortion is the mother of all evil!” OMG!!, OMG!! Who knew??. Somebody call a priest!!

“Annoying curves at the edges of the picture” (“it often it results in a drop off in sharpness towards the edges”) Oy Vey! Call the optical cops!! As I mentioned in my last reply, this “annoying curves” business is nothing more than an aesthetic conceit which is ultimately irrelevant to dash cam use. Unlike you, for whom the whole concept of dash cam video is theoretical and seen from the perspective of your castle in the air, I have been in the position of having to actually submit numerous dash cam videos to law enforcement which were used in litigating a criminal matter. Not one LEO, or prosecutor or attorney or courtroom official ever concerned themselves with some modest curvature in the images from the wide angle lenses in any of my cameras.

One of the few places “Distortion is the mother of all evil!” is in specialized macro work where only a few lenses on the market provide true flatness of field. I happen to own one (a vintage Nikon). I used it not long ago to photograph some very rare post WWII era postage stamps from Poland for use in an upcoming book. You don't want high quality images of rare stamps to look distorted or out of square in reproduction. Now THAT would be annoying. This is where flatness of field in a lens comes into its own. For dash cam video, not so much.

You know, c4rc4m, once again here you show your “half-knowledge” about optics. Let me re-quoted you from above. - “Annoying curves at the edges of the picture” (“it often it results in a drop off in sharpness towards the edges”)You are conflating barrel distortion with curvature of field. While related, edge sharpness has nothing to do with barrel distortion. One is a matter of distortion while the other is a matter of “plane of focus”. With barrel distortion all parts of the image are sharply focused, but show distortion because image magnification decreases with distance from the optical axis. With “plane of focus” issues you can even have “wavy edge to edge sharpness” due to the compounded effect of the different lens element duplets where you end up with the center appearing very sharp while the mid-frame is softer in comparison and the corners being better than the mid-frame. All this is all affected by the aperture you use ( but is fixed in our case) and which has no effect on the barrel distortion. In other words you could have a lens that yields almost zero barrel distortion that still has soft edge focus as they are caused by two different optical phenomenon. You could also have the inverse, a lens with perfect edge to edge sharpness but with significant barrel distortion. Some extreme fish-eye short focal length lenses on the market from Canon and Nikon provide some of the best edge to edge sharpness you can find. In fact, lenses with barrel distortion tend to be sharper along the edges which is why correcting for it can be difficult and costly.

And what is this business you suggest about downsampling? This is dash cam video not Photoshop. Downsampling an image will degrade it which defeats your whole “high end lens” purpose in the first place. Downsampling can even cause optical distortions due to the effect of aliasing if not done properly. I used to see this all the time when I worked doing pre-press for a printing company and people who didn't know what they were doing would submit problematic files. BTW, speaking of down sampling much of the video I had to submit for the criminal matter was RAW, direct from the camera native resolution because it was a legal matter, so no “downsampling” allowed.

6. I never said ANYTHING about discarding lenses. I was encouraging you to put money away so you can buy a suitable camera and one of these super low distortion high end lenses you seem so enamored with so you can finally expereince the results for yourself and report back to us about it, especially because you grouse above that, "no-one has tested high MP lenses on any of the dashcameras so far". One way or another sincw this is your "thing" I'm sure you'll really enjoy yourself and it would be very interesting to see what you come up with. But I'd hate to see you spend your money one a fancy lens and then discard it. Don't do that.

Having said this, I'm delighted to hear that within 24 hours of my encouraging you to buy a new Mobius that you ordered a Maxi. Hopefully, you'll get some more overtime at work and will eventually buy one of these lenses you keep touting. Just try not to drop it on the pavement this time.

 

[c4rc4m]

For someone who wasn't going to enagage in rants and arguments that's a very long post of the same. I see you've taken a dislike to another member and recently engaged in a personal rant against them recently in another thread.....

As for your points, I'm not going to engage in you long arguments suffice to say - "suggesting someone might like to try testing a lens" is the same as a "recommendation" and it's just semantics. Utter bull. Saying I recommend this lens go out and buy it is very different to saying I've found this lens, anyone want to try it.

"You'll never the see the difference with these high end lenses" - I have experience of high end lenses and I have seen the difference, albeit not on a dashcam. Is the difference worth it for price vs performance? That's a whole other argument but you're whole Treeye lens thread of 3mp vs 5mp disproves your own point on this one because you and others have seen the benefits.

As for down scaling, yes I'm talking in digital terms rather than in picture terms, but lets put it like this Dashmallow, the sensor isn't recording the scene. It's recording the scene as fed to it by the lens. The lens is projecting an image of the scene onto the sensor which then records it. Simple fact here, a higher resolution lens produces a sharper image with sharper edges. Ergo, the image recorded by the sensor at whatever pixel value the sensor records at will be sharper.

Hence why professional photographers use professional lenses and hence why as a consumer you cannot match the sharpness of a professional image with a consumer lens. The lens is the limiting factor.

 

[dirkzelf]

Really guys?

 

[TonyM]

Please can we get back on-topic and talk about the Maxi?
----------------------------------------------------------------
Are there any specific features you would like to see improved / added to the Maxi, for dashcam or any other use? Please keep your suggestions reasonable - I don't think Mobius will make a $200 lens option available!

 

[Paul Blart]

Please can we get back on-topic and talk about the Maxi?
----------------------------------------------------------------
Are there any specific features you would like to see improved / added to the Maxi, for dashcam or any other use? Please keep your suggestions reasonable - I don't think Mobius will make a $200 lens option available!

Would be good to have a live view via wifi as would make setting the camera up much easier.

 

[dirkzelf]

Would be good to have a live view via wifi as would make setting the camera up much easier.

N

Nah, doesn't really matter... Have that with the JooVuu X and foxeer Legend 2 as well, never used it to point the camera... Could be useful if you have a telelens mounted, but for dashcam use, just point straight forward, an of you go!

 

[Dashmellow]

For someone who wasn't going to enagage in rants and arguments that's a very long post of the same. I see you've taken a dislike to another member and recently engaged in a personal rant against them recently in another thread.....

As for your points, I'm not going to engage in you long arguments suffice to say - "suggesting someone might like to try testing a lens" is the same as a "recommendation" and it's just semantics. Utter bull. Saying I recommend this lens go out and buy it is very different to saying I've found this lens, anyone want to try it.

"You'll never the see the difference with these high end lenses" - I have experience of high end lenses and I have seen the difference, albeit not on a dashcam. Is the difference worth it for price vs performance? That's a whole other argument but you're whole Treeye lens thread of 3mp vs 5mp disproves your own point on this one because you and others have seen the benefits.

As for down scaling, yes I'm talking in digital terms rather than in picture terms, but lets put it like this Dashmallow, the sensor isn't recording the scene. It's recording the scene as fed to it by the lens. The lens is projecting an image of the scene onto the sensor which then records it. Simple fact here, a higher resolution lens produces a sharper image with sharper edges. Ergo, the image recorded by the sensor at whatever pixel value the sensor records at will be sharper.

Hence why professional photographers use professional lenses and hence why as a consumer you cannot match the sharpness of a professional image with a consumer lens. The lens is the limiting factor.

Hey man, keep livin' the dream.

 

[c4rc4m]

Would be good to have a live view via wifi as would make setting the camera up much easier.

I think it could be quite useful to avoid getting too much sky in the picture. Also for lens modders, having a live view would help a lot with focusing a new lens.

 

[dirkzelf]

I think it could be quite useful to avoid getting too much sky in the picture. Also for lens modders, having a live view would help a lot with focusing a new lens.

Very helpful for focusing the lens for sure!

 

[tempviewer12]

Please can we get back on-topic and talk about the Maxi?
----------------------------------------------------------------
Are there any specific features you would like to see improved / added to the Maxi, for dashcam or any other use? Please keep your suggestions reasonable - I don't think Mobius will make a $200 lens option available!

Having functional WiFi would be a great start. Being able to download video's and photo's without having to remove the SD card or plug in a USB lead would be a godsend. For starters, I don't have a laptop, and I don't have an Android phone either - so I am forced to remove the SD card every time I want to download something. This would be ok if it wasnt for the fact I've built my Maxi into my car to the point I need to remove trim panels to access the card.

 

[jokiin]

Using wi-fi can be convenient to grab a single file off the camera, if you want to get multiple files it very quickly becomes a chore, pulling the card out is more practical due to file sizes

 

[c4rc4m]

Run into an interesting issue with the Mobius Maxi tonight - Vegas Pro Video Editor won't open Mobius MP4 files. It says they are an unknown format or corrupt. They do play in WIn Media which suggests it's a peculiarity with the Mp4 settings rather than corruption.

Video settings were: 2.7K, Extreme Fine, 30fps, Mp4.

 

[TonyM]

There are compatibility issues with the mjpg 2.7k video files and some video applications. I typically use avidemux to clip my video files before uploading them, but it doesn't like to clip the Maxi files unless I re-encode them.