EEVblog Electronics Community Forum
Products => Thermal Imaging => Topic started by: Noy on October 21, 2019, 06:56:40 am
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Hi guys and girls,
i have a Seek Thermal XR and want to build a macro lens.
After many threads and youtube videos i found a supplier for "cheap but "good" quality" USA ZnSe, meniscus, II-VI, CVD lenses with different diameters (i will use 20mm) and different focal length.
Each lens will cost 19€ so it will be a bit pricey to order 1.5" , 2", 4" lenses.
So can somebody post pictures with the different focal length on an XR? Maybe somebody tried the different ones.
Or which focal length is the right one, which one do you suggest?
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Here are a few quick examples for you. The subject is a USB "sound card" with HS100B chip. The components are mostly 0603, but there are 3 0402 resistors on the pads above the wire at the left. The IC pins are .5mm pitch.
First image is with with the XR at farthest focus & 1" ZnSe lens
Second image is with the XR at closest focus and 4" ZnSe lens
Third image is the XR at closest focus & 1" ZnSe lens
These are NOT meniscus lenses.
For some reason it refuses to put the images in the order I added them so I had to rearrange my text.
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Thank you for these images. Now i know 1" is to close for my purpose.
So 2" or 4"..
Do you or somebody else has a 2" lens maybe?
Or i will go for a 3" middle between 2 and 4..
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Can you detail the supplier of the lenses as Meniscus are very nice compared to Plano Convex or bi-convex types. 19 Euros is an excellent price and I would like to buy some for my close-up lens needs.
Fraser
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Of course:
https://de.aliexpress.com/item/32234326702.html?spm=a2g0s.9042311.0.0.69834c4d1wgvop
I picked the 2,5" 20mm II-VI Version.
I think it fits (hopefully)..
I put the lens into my shopping cart with the mobile app and after 24h in my shopping cart it was reduced to 16€ :-)
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Thanks :)
Fraser
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Thank you for these images. Now i know 1" is to close for my purpose.
So 2" or 4"..
Do you or somebody else has a 2" lens maybe?
Or i will go for a 3" middle between 2 and 4..
You're welcome. Sorry I was not awake to answer your question before it was too late. I do have a 2" or 2.5" lens but it is 25mm diameter and would have taken more effort to strap it onto the XR. The 1" & 4" lenses used above are both 20mm dia. and are perfect size for the purpose. All I had to do to strap them on is wrap a strip of thin cardboard around the Seek knob, glue it together, cut another strip a few mm wide & glue a few layers around the inside of one end of the first strip to make a retaining ring, drop the lens in & slip it back onto the Seek. :)
In my rush to get to bed I forgot I was going to say that if you are brave & a bit "crafty" you could also remove the stock lens & make a mount for the 1" ZnSe lens to use it directly. Then you could get the camera much farther away from the circuitry & still get a magnified & focused view. The 2.5" lens might put you impractically far from the circuit though. The 1" lens is also the longest focal length for which you could achieve the F/1.4 aperture the stock lens has, thus having a chance of keeping correct temperature readings.
The meniscus lens might also (and hopefully) make for a clearer image than what I get with the plano-convex lens:
[attach=1]
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Hi, no problem. Hope you slept well.
I still can stop the order, but i think i will try it.
I don't want to crack the case because the seek is only a few months old and still has "German" warranty.
Im owning a 3D printer and will print this 20mm adapter ring for the seek.
"Exact" temperature is not so important i use the seek to find failures on electric devices and normaly a faulty part is a lot hotter than the good ones.
1" like you showed in your picture (1 post) if it IS mounted in front of the original lens is to close (magnified and distance to the PCB) for my purpose. And the 4" looks like nearly the same (magnification and PCB distance) like the original lens or? So i thought 2,5" should be good.!?
Maybe i will order a 1" (they have only 1.5") ?additionally if the warranty is void in future.
Your last picture shows a 1" lens but it replaced the original or? So you have to crack the case for this zoom?
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I totally understand and agree regarding the warranty & cracking open the camera. Yes it needs to be opened in order to get the stock lens out; at least I haven't found a way to get the knob off otherwise. The non-XR is different since the knob is more flexible it can be pried off, but the bayonet is smaller on the no-XR so not so easy to substitute a lens. You can see what these look like in the Seek Thermal lens repair thread.https://www.eevblog.com/forum/thermal-imaging/seek-thermal-lens-repair/ (https://www.eevblog.com/forum/thermal-imaging/seek-thermal-lens-repair/)
The other option once you have cracked it open is to remove the pin that limits the focus range & then you can focus down to about 2".
Yes that last photo is with the 1" lens replacing the stock lens.
I have a photo of that audio device with the stock lens from 8" away which is about what they say is closest focus for the XR:
[attach=1]
This is the back of a Seek pcb taken with an XR focused at 2":
[attach=2]
Like this. :)
[attach=3]
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Thanks, currently the chinese shipped the lens (very fast this time...). So i will try and post some photos here (in a few weeks.. :-\)
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Thanks, currently the chinese shipped the lens (very fast this time...). So i will try and post some photos here (in a few weeks.. :-\)
I know I'm late, but were you able to get the lens and if so can you post some sample shots.
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Sorry, took some time I'm busy currently..
Did 2 pictures with the seek handy app and an "semiproffesional" mount (velcrostrap + camera mount (for bigger cameras so a bit shaky)).
First picture zoomed max; 40mm above inductor (IHLP5050 vishay).
Second one 65mm above inductor min zoomed the small parts near are 0402.