EEVblog Electronics Community Forum
Products => Thermal Imaging => Topic started by: Fraser on January 28, 2018, 02:54:09 pm
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I promised myself not to buy more thermal cameras unless something very special came along. So far so good, no new cameras in the collection :) I have, however, purchased another auxilliary lens for use with my cameras.
As readers of my posts will know, I previously purchased a very nice brand new Fluke Tele2 X2 telephoto auxilliary lens that improves distance viewing on a thermal camera fitted with an approx 24 Degree FOV objective. With the Tele2 fitted you get 12 Degrees FOV. Very useful. The lens elements are 'proper' high quality Germanium units so image quality is excellent. No cheap molded Chalcogenide IR glass here ;D The lens exit diameter perfectly matches into my FLIR Exx series camera and only a mounting adapter is needed to join the two together.
I have been watching a brand new Fluke Wide2 lens for some time. It provides x0.5 magnification on a camera fitted with an approx 24 Degree FOV lens. The result is a 48 Degree FOV :) Good for building observation and work in tight spaces. The seller originally asked around £500 for the lens but it did not sell. It is equipped with Germanium lens elements, just like its stable mate, the Tele2. I was interested, but not at £500! The lens has failed to sell for many weeks. Likely because Fluke are giving away such a lens with new Fluke camera purchases and also many people would not realise that these lenses will work in front of most modern thermal cameras that have an approx 24 Degree FOV lens fitted. The mounting is the only real barrier to using them. The seller recently dropped the price of his lens down to £250 which is actually a very good price. Normal retail is over £1200. I made him an offer yesterday as eBay provided a '£15 off spends over £75' voucher for me to use until midnight last night. I am pleased to say the seller accepted and I got the lens for a smidge over £200. A very good price for what it is. Not exactly cheap, but then not much connected with thermal imaging is ! I could always resell these lenses further down the line as I know how to correctly pitch them to thermal camera owners ;) If well cared for, high quality lenses will always have a good resale market.
So now I have the X2 and X0.5 auxilliary lenses to mount on my E40(E60) and at a fraction of the price FLIR charge for their versions. I know I will need to check the transmission losses etc of the Fluke lenses but I have the required Black Body references and the Exx series permit a calibration offset entry for using custom lenses like those that I will be using :)
Now the challenging bit for me. I may know a little about thermal imaging cameras, but I am still very much a beginner when it comes to CAD and 3D printing. The Fluke auxilliary lenses appear to use a bayonet mount very similar to that found on Micro 4/3 cameras. The diameter is correct at just under 38mm. The FLIR Exx camera (not the Ex5 series) use a larger diameter bayonet mount. I will need to design an adapter that accepts a 38mm bayonet Micro 4/3 mount and presents an upsized bayonet mount to the Exx camera. This may not be a very complex task for seasoned CAD engineers, but it will be a first for me.
Any hints or tips on producing the required 'wings' of the male and female bayonet mounts is welcomed. I may try to adapt other bayonet mount designs that are on Thingiverse if I get really stuck, but it would be good to know how to make such mounts in case of future need. Thankfully the lenses are quite light so an ABS lens mount adapter should cope OK, and if they break I can just print another :)
Pictures of the Fluke lenses attached, followed by the genuine FLIR Exx mount lenses. Note that FLIR use aluminium brackets to adapt some of their more exotic lenses to fit on cameras with a different mount. Lens shown in bottom right of FLIR Exx lens group photo. In this case, the bracket attaches to the Exx tripod hard point under the camera lens.
Fraser
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About the lenses produced for use by Fluke on their cameras.....
http://www.fluke.com/fluke/uken/products/ir-lenses (http://www.fluke.com/fluke/uken/products/ir-lenses)
If I recall correctly, they use Jenoptik Germanium lenses, a much respected producer of high quality thermal imaging optics.
Fraser
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A couple of Bayonet mount designs found on Thingiverse. They look very nice and may be adaptable to my needs. The first is a close-up lens apater for a FLIR camera. The second is a stackable Micro 4/3 extension tube for macro work.
Fraser
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Hey Fraser, glad you found other ways to spent money...
I still check this forum daily, but I can't participate in all threads - but for this one I might be able to help.
I have recently ventured into filmmaking and got myself a cinema camera. The tinkerer that I am, I looked up what can possible be printed for my camera and surprised to find a few things on thingiverse. But there are mostly .STLs and those are hard to modify... Maybe in TinkerCAD, but highly limited. You can always contact the artists and ask for CAD files to use in fusion360.
Then I googled around and learned that there are websites where you can get cad models, and lucky enough. Grabcad had a male and female model of the micro four thirds mount. I used those to model a d mount(60's bolex) to mft.... I hadn't had success yet due to bad print theory(overhangs and supports). Printing at 0.07 layer height, full infill and 40mm/s in PLA yielded working results. But the mft adapter probably works with .2 res as well. I needed to 0.07 for the thread.
So my tip for you: look through other websites and find cad models of the cameras, lenses or mounts - or email flir and fluke for those. Adapt those cad models into your CAD software.
I can help you with links, but I am backstage at a theatre play right now so I might only get to that tommorow. I offered help with models before and didn't go to it in the end, so I might lose motivation.
Attachments: thermal image of my camera shooting a timelapse of my cactus. I watered it and saw it generating heat... But after 3 hours no visual difference.
images of the Adapters I recently modeled and printed.
https://i.imgur.com/IUDccKgr.png
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I printed the two lens adapters that I previously detailed in order to assess their suitability for adaption to my needs. I printed them in rough draft form but they have provided what I needed to know.
The FLIR Close-up lens adapter fits my Exx even though it was designed for another model of FLIR camera the lens mount is obviously the same :) I can therefore use the bayonet mount design as the basis for my Fluke lens adapter.
https://www.thingiverse.com/thing:1078735 (https://www.thingiverse.com/thing:1078735)
It is stated as fitting the following cameras but the Exx series may be added to that list.
A-Series: A300, A310, A315, A320, A325, A325sc
B-Series: B200, B250, B300, B360 & B400
SC-Series: SC305
T-Series: T200, T250, T300, T360, T400, T420, T420bx, T440 & T440bx
The micro 4/3 adapter was not quite so good. The bayonet openings are slightly too narrow in two locations, and the bayonet protrusions on the Fluke lens are slightly greater diameter than that of the micro 4/3 specification. I enlarged the bayonet openings with a scalpel as a quick mod, but the whole adapter needs reviewing in terms of various diameters to be compatible with the Fluke lens mount. This will need more work and it may be better to design my own version of that part of the mount.
https://www.thingiverse.com/thing:2012640 (https://www.thingiverse.com/thing:2012640)
Once I have two suitable bayonet mount designs, I will merge them into a single part.
Pictures attached. It is a pretty good start to my project :) It is great to be able to create draft versions so quickly on my own printer. It is so helpful to test, inspect and assess a physical draft of a design :-+
Fraser
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Well there has been an interesting development in this project. The "Wide2" lens arrived today.
It turns out it is not a Wide2, but rather a Tele2 :palm: The seller misidentified it.
Am I annoyed ? No, not really. A X2 telephoto auxilliary lens is far more useful to me. Sadly it is a duplicate of my other Tele2 though. It was a very good price, so no harm done.
Fraser
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I just checked and the Fluke Tele2 works perfectly with my PS32 scope as that has a 24 Degree FOV lens on its TAU Core. I will need to make a mount adapter for the PS32 and my HS324 'Command' scope as that is a good match as well. These adapters will have to wait until I complete the Exx adapter. I will be able to create a 'universal' Fluke bayonet mount receptacle that may be incorporated into designs to mate with differing camera requirements.
I have a X0.5 wide angle auxilliary lens for my PM series that I can mount on the Exx if required. Another mount adapter to be designed then ;D Then there are the X0.5 Inframetrics wide angle lens and Close-Up lenses to look at. You never know I might get quite good at designing mount adapters after all this practice !
Fraser