I've just stopped using my mounting plate with 3 Mobius cameras together on a single helmet mount, as I was getting too much vibration in the video.Focus looks to be where it was set. 8 and 12 are a little jumpy due to the overall weight. Need to add a fresh layer of EVA foam to the mounting plate.
I found just the same with my 6mm f1.2. It can look very good one day, but out of focus the next. I think the act of tightening the set screw affects the focus too. These fast lenses are potentially very useful, but they're a pain to work with.The ƒ/1.2 lenses don't give you too much room for error with the shallow depth of field they provide. Sometimes, I find that what looks good when I'm focusing doesn't look quite so good when I go to shoot actual video and so then I'll have to go back and make an adjustment.
I've just stopped using my mounting plate with 3 Mobius cameras together on a single helmet mount, as I was getting too much vibration in the video.
You make a lot of good points there. It's evident that you have made mistakes previously with your G1WH that some of us are making now with our mobius cameras.I have to disagree with your approach here. Having to modify the case on a Mobius is only a "common problem" if you are in the habit of purchasing lenses that are not compatible with the camera in the first place. While I would certainly be willing to modify the case (or other components such as the threaded lens module barrel) on a Mobius camera if I needed to (and I have), the goal should be to install compatible lenses in the first place. I think it's fine to modify a camera if you need to for a specific lens but I believe doing so should be the exception, not the rule.
A week ago in this thread I tried to make the case that it is best to order lenses from a knowledgeable vendor who is able to provide all the technical information you need to make an intelligent lens buying decision.
The consequences of buying from a vendor who tells you absolutely nothing about what they are selling you result in the kind of experience @jackalopephoto reported yesterday where he says, "But the 12mm lens and the 8mm lens can't focus on the Mobius. The housing blocks them before they can screw in far enough. You would have to modify the case". This is exactly the kind of outcome I was cautioning about.
If you want to install an aftermarket lens in your camera, the first thing you need to do is measure the thread depth of the lens module on your camera. In the case of the Mobius it is 12.5mm. Then add the distance from the lip of the module to the front of the camera's case. Now you how long the threaded barrel on the new lens needs to be in order for it to screw into the barrel as far as required. As long as the lens is narrow enough but with a long enough threaded barrel, you don't need to worry about the size of the hole in the case.
View attachment 36034
I first encountered and learned about this issue several years ago when installed a different lens into my old G1WH. The first three lenses I tried wouldn't work because of the thread depth on both the lens and the module barrel. While I did have to make an alteration the camera's housing, even without the front of the case even on the camera three different lenses would not work at all because I couldn't screw them far enough into the barrel to achieve focus because the threaded part of the lens barrels were not long enough. They couldn't screw in far enough for those particular lenses BFL requirements. I discovered that on many M12 lenses the threads do not go all the way up the full length of the barrel and of course some lenses don't have very long barrels, so now when I consider an alternative lens for a camera that's one of the first things I look for.
The basic (installation) specs to look for when shopping for a lens are BFL, (back focal length) MBF (minimum back focus), and lens thread depth. These specs work in concert with the module's threaded lens barrel. Obviously the specific size sensor and all the other specs are important to know but the BFL, MBF and thread depth are the specs you need to know regarding whether the lens can even be installed and focused. This is critical. If these numbers are not right, look elsewhere for an appropriate lens to fit your camera; there are literally hundreds of lenses to chose from. The way I see it, if the specialized lens you purchased requires you to permanently alter the housing of the camera, then you've probably chosen the wrong lens. Obviously, if this happens to be the only lens that will achieve the desired results, that's another story.
Treeye and Peau Productions are two examples of professional lens vendors who go out of their way to provide buyers with everything they need to know before purchase so that you end up with a compatible lens that will meet your requirements.
Peau Productions, as an action camera specialist even goes to the trouble of categorizing many of their lens offings according to their compatibility to specific cameras and like Treeye they publish all available lens specifications.
Here for example, is the information Treeye provides for the 6mm ƒ/1.2 Starlight telephoto lens. Not only do they provide all the necessary specifications to know if the lens meets your requirements they also provide a technical drawing of the lens so you know the exact physical measurements of the lens. This way you you know the thread depth on the lens along with everything else about how it will fit your camera before purchasing.
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I've labeled the required fitting specs in blue.
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You make a lot of good points there. It's evident that you have made mistakes previously with your G1WH that some of us are making now with our mobius cameras.
Even the 3no telephoto lenses that eletoponline365 sent to me to evaluate don't work in a regular mobius case!
Did you get your Treeye 6mm F1.2 to fit in a standard mobius case?
Following my issues with fitting various lenses into cases, I decided to buy some digital calipers so I could take appropriate measurements before ordering any more lenses.The diameter of the 6mm ƒ/1.2 lens barrel is a perfect snug fit for the lens opening in the M1 housing so it is very secure and stable.
That's where the technical lens drawing with all the detailed measurements provided by Treeye comes in handy when ordering.
I found just the same with my 6mm f1.2. It can look very good one day, but out of focus the next. I think the act of tightening the set screw affects the focus too. These fast lenses are potentially very useful, but they're a pain to work with.
As far as I can tell, that stuff is made for sealing luminaires, outdoor lighting fixtures, car headlights and stuff like that. When they talk about "optical lens sealant", I think "lens" in this instance means what goes onto the light fixture and not camera "lenses".
While we're on the subject of adhesives - for cameras without a set screw in the lens holder, what would you recommend for fixing a lens in place once you have achieved the correct focus?
Came up as a suggestion while browsing through butyl rubber sealant listings.
"No solvents, corrosion, and pollution", I think they mean there isn't any corrosive fuming. If applied judiciously, should work.
While we're on the subject of adhesives - for cameras without a set screw in the lens holder, what would you recommend for fixing a lens in place once you have achieved the correct focus?
Here's a place (and it's a great fun web site) that sells taps for tinny screws:
metric: https://www.micromark.com/Metric-Tap
standard: https://www.micromark.com/Tap-Drill_3
The Mobius set screw appears to be M2. Finding a set screw to fit may be a challenge though. Amazon has a bunch of "eye glasses screw" repair kits but that appears to be M1 to M1.6.
Argh... I am unable to access these sites(corporate firewall). Oh well... I guess perhaps it's for the best; productivity would have really taken a dive
.
I know what you mean about having to buy a tool just for that one project. And usually it's the odd ball tool specific just for that job and that cost an exorbitant sum too ( I am looking at you Audi).
What about this here "reusable thread locker":
https://www.mcmaster.com/#threadlockers/=1bdurrj
View attachment 36143
We have this in the lab and other than being a bit messy, does what it supposed to. You can also apply a dab on the outside, overlapping the screw and the support. It would work similarly to the red or green lacquer that is sometimes used for temper evidence but remains somewhat soft.
Amazon also sells this stuff:
https://www.amazon.com/gp/B0088YEGXM
Argh... I am unable to access these sites(corporate firewall). Oh well... I guess perhaps it's for the best; productivity would have really taken a dive
.
I know what you mean about having to buy a tool just for that one project. And usually it's the odd ball tool specific just for that job and that cost an exorbitant sum too ( I am looking at you Audi).
What about this here "reusable thread locker":
https://www.mcmaster.com/#threadlockers/=1bdurrj
View attachment 36143
We have this in the lab and other than being a bit messy, does what it supposed to. You can also apply a dab on the outside, overlapping the screw and the support. It would work similarly to the red or green lacquer that is sometimes used for temper evidence but remains somewhat soft.
Amazon also sells this stuff:
https://www.amazon.com/gp/B0088YEGXM