[HN Gopher] Show HN: I shot high-res stitched panoramas in Icela...
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Show HN: I shot high-res stitched panoramas in Iceland using a
thermal camera
Author : dheera
Score : 403 points
Date : 2021-01-02 17:00 UTC (5 hours ago)
(HTM) web link (petapixel.com)
(TXT) w3m dump (petapixel.com)
| mmaunder wrote:
| I'm curious what kind of thermal camera he's using.
|
| I bought a Therm-App Pro 640x480 a while back and it's quite good
| - and reasonably priced compared to Flir - along with a github
| repo for different false color palettes. But what's really weird
| is it seems to not be available anymore. I'm guessing export
| restrictions or massive demand for thermal cameras during Covid
| along with supply chain issues. IIRC it is also 25 frames a
| second, which is unusually high for thermal cameras due to export
| restrictions.
|
| Edit: Here's a post on creating panoramic images with therm-app.
| https://www.flickr.com/groups/therm-app-users/discuss/721576...
| [deleted]
| [deleted]
| giantg2 wrote:
| Looks really nice. I see one for sale in the US. $4k though.
| dheera wrote:
| OP here. Seek RevealPro. I added a top-level comment with some
| more details and links :)
| mmaunder wrote:
| Thanks OP. Really great work on those Iceland pics. It's an
| original concept I haven't seen before - adding thermal data
| to panoramas of landscapes with geothermal heat. So cool. I'm
| a bit jealous I didn't think of it first.
|
| Sounds like you have a science background and field, but I'd
| encourage you to think of these as art and chat to a few
| galleries about an exhibition. At the very least it would be
| fun, and pretty amazing to see big blowups of your own
| imagery. They may be able to do a virtual exhibition during
| Covid.
| dheera wrote:
| > chat to a few galleries about an exhibition
|
| I would love to! I'm a physics/EE major by training and
| career-wise I'm focused on ML and robotics, but I love art
| and _especially_ using art to visualize science in ways
| that are understandable to the general public. (I 'm also
| doing an astrophotography project to show the visual sizes
| of various nebulae. Your usual NASA photos don't really
| provide any sense of scale, and many people have the
| misconception that you need insane magnification to see
| them, but there are actually a whole lot of objects that
| are visually much bigger than the moon, just too dim to
| see.)
|
| Being an engineer by background my network is mostly
| engineers -- I don't really have any strong connections
| with galleries and media, but I'll be on the lookout for
| them! I welcome intros if anyone would be so kind. :) TIA!
| bobbob1921 wrote:
| I was wondering this too, the author added this info via a
| reply in the comments (of his site/article , not HN)-
|
| > Author here. The camera was a Seek RevealPro which has
| 320x240 resolution. The thermal data in the panoramas are
| stitched together from raw data exported by the camera and
| represented as color (hue+saturation, as per scale in upper
| right, represents temperature data).
|
| The brightness channel is piecewise-linearly combined with a
| corresponding visual image taken with a regular SLR to provide
| a visual reference of what you're looking at.
| mmaunder wrote:
| I think the ThermApp cameras had the ability to combine a
| visual photo, but I haven't used mine for quite some time so
| I may be wrong.
| ChrisMarshallNY wrote:
| Awesome stuff! Thanks for sharing it!
|
| I'm used to thermal cameras being so lo-res you can barely tell
| what they are.
| ahmadhamza19 wrote:
| Really amazing photos.
| pachico wrote:
| From what I know, it's hard not do do awesome pictures in
| Iceland. What a marvelous place...
| NDimCube wrote:
| Nice results, thermal cameras aren't easy to work with,
| especially in terms of artistic result. I've seen problems with
| stitching resulting with artifacts in panoramas. As I understood
| (I'm not thermal cameras expert) it's due too the fact that
| sensor warms up -> thermal camera calibration doesn't correct the
| result enough -> stitching needs corrections.
|
| To put it one dimension higher, in Pix4D we work on 3d models
| based on the thermal images:
| https://www.youtube.com/watch?v=x-jp9a1bpVU Example:
| https://sketchfab.com/3d-models/thermal-model-of-pix4d-headq...
| supernova87a wrote:
| If only the cost of thermal imagers could come down and be more
| affordable, more people might be interested!
| SoSoRoCoCo wrote:
| It's $570:
|
| https://www.amazon.com/Seek-RQ-AAA-Thermal-Revealpro/dp/B07B...
| jcims wrote:
| That and the associated optics.
|
| There's some reason for encouragement however. I bought a Seek
| Pro, with 320x240 resolution, on sale for $350 earlier this
| year. The app is pretty terrible unfortunately and the camera
| physical construction is flimsy, but the imager seems to be of
| reasonable quality for the price point.
|
| Couple of examples: https://imgur.com/a/ZGsOwUm
| ampdepolymerase wrote:
| Thermal imaging resolution is restricted by arm control laws
| unfortunately. There are forces at work beyond market forces.
| jcims wrote:
| ITAR compliance assurance isn't free and certainly impacts
| operational costs, but the sensor I have isn't export
| controlled and still normally costs >$1K when you buy it
| from FLIR.
| jansan wrote:
| I once rented an IR camera for roughly 100EUR. This is
| probably the best option for people who only need IR cameras
| on very few occasions.
|
| Will we ever see chap(ish) IR cameras? Is there an
| alternative to germanium lenses on the horizon?
| CamperBob2 wrote:
| Zinc selenide lenses for laser cutters work very well in
| the spectral range covered by consumer IR cameras. They are
| dirt cheap on eBay, Ali Express, and other places.
| jcims wrote:
| I believe there are some metamaterial-based approaches for
| the actual microbolometers that should help drive costs
| down. Ostensibly metamaterials could also be used for
| lenses but I'm not aware of anything there, we're probably
| stuck with germanium for the time being.
| giantg2 wrote:
| That carboy is pretty hot.
| jcims wrote:
| It was a pretty hot yeast: https://i.imgur.com/YGhx1kr.jpg
| gandalfian wrote:
| Yes I do covet them. Getting cheaper but still fairly low
| resolution. Keep hoping for a tipping point like digital
| cameras where cheap decent sensors will suddenly be everywhere.
| Not yet though.
| soared wrote:
| I'd imagine demand for thermal imaging has skyrocketed due to
| covid, so its possible the tech will get better and cheaper.
| jstanley wrote:
| I bought one on eBay a few years ago for about PS300, but it
| sucked so I got rid of it. It used a traditional camera to draw
| most of the image (itself already quite low-res), and just
| highlighted even-more-low-res temperature data in blue and red.
| SoSoRoCoCo wrote:
| I was just considering buying one. Would you share your
| thoughts?
| jstanley wrote:
| The resolution was too low.
|
| I didn't really have a use in mind for it, I just thought
| it was interesting and thought I'd find uses for it after I
| owned it, but the resolution was too low to be able to do
| anything useful.
|
| Here's the only picture I have of it working:
| https://img.jes.xxx/1047
|
| As you can see, you can't see anything.
| SoSoRoCoCo wrote:
| > As you can see, you can't see anything.
|
| Thank you.
|
| I wanted to get one to (a) find creatures outside at
| night while camping, and (b) fix my house energy leaks.
| But that rez seems awfully low. So amazed at the OP for
| doing such an amazing job stitching images!
| dheera wrote:
| I've had decent luck finding and seeing creatures with
| the Seek RevealPro I used, although there may be better
| ones out by now.
|
| I even used it to try to find a friend's lost cat once. I
| didn't succeed in finding the cat with it, but I did end
| up finding a few other stray cats and racoons. (For
| anyone wondering, the pet cat was found later and was
| taken to a shelter by some good samaritan.)
| dheera wrote:
| Hi everyone, OP here.
|
| I used a Seek RevealPro which outputs TIFF files that contain
| 32-bit floating point values. I created a script that takes in a
| Seek TIFF and outputs an 8-bit greyscale integer TIFF:
|
| https://github.com/dheera/iceland-thermal/blob/master/script...
|
| I then panoramically stitched those 8-bit TIFFs together (some
| with the help of hugin, and some manually with GIMP) and
| distortion-corrected them as best as I could to a black-and-white
| visible light image. I also created an artistically-chosen color
| map for each image. For the final output image, hue and
| saturation are fully based on thermal data, and lightness is a
| combination of thermal and visible data. Scripts to generate the
| final output images, along with the panoramically pre-stitched
| data, and the color maps I used:
|
| https://github.com/dheera/iceland-thermal
|
| Also, my Instagram, which is mostly astrophotography of late, but
| I did post thermal images there before and I may do so in the
| future again if I can find another good set of interesting
| thermal subjects to do this in!
|
| https://instagram.com/dheeranet/
| skybrian wrote:
| Have you tried any other thermal cameras and how did they
| compare?
| dheera wrote:
| Not too many, for personal projects I'm mostly budget-
| constrained. I tried the Flir C2 but the thermal data was
| extremely low resolution, and returned it. I also tried a
| Flir Lepton 2 module since I could use an RPi and some
| gadgetry to do the panorama scanning and stitching
| automatically, but it too was low resolution (80x60).
|
| The Lepton 3 seems to be decent at 160x120 though, which is
| probably good enough for a project like this, so if I were
| doing this again I'd probably use a Lepton 3 and a 2-axis
| servo scanner with a RPi, and maybe even combine it with an
| RPi HQ camera to automate the entire process into a single
| push button.
|
| The Seek RevealPro is slightly annoying in that it doesn't
| have programmatic access so I had to press a button to take
| every piece of the panorama. It's a great general-use device
| though. I use it when camping or doing astrophotography in
| remote locations for some peace of mind since I can spot any
| potential wildlife and people threats from a distance, and I
| can easily identify whether a parked or seemingly abandoned
| car has been recently occupied. (My fears may be unfounded,
| but either way I'm much more at ease when I can see in the
| dark.)
| giantg2 wrote:
| I was recently looking at the Lepton. I would really like a
| to make an affordable monocular. It seemed like the image
| quality was quite low even for the 160. I'm not sure if
| adding some lenses for magnification would improve them or
| not. The refresh rate is pretty slow too. I'd love to
| experiment with it, but $200 is a lot for a project that
| might not be usable.
|
| The Boson seems like it has great clarity and refresh rate,
| but at that price I might as well just buy a purpose made
| device (outside my price range).
| tpmx wrote:
| That photo with the icelandic horses - how did you pull that
| off with a QVGA-resolution thermal camera + stitching? Animals
| tend to move...
| dheera wrote:
| Yeah so I tried to get that shot about a dozen times on
| various farms before I finally found some horses that seemed
| tired, lethargic, and didn't move too fast.
|
| I also had to stand there for a good 15 minutes in the biting
| cold before they stopped being interested in me and kind of
| just stood there.
|
| They still occasionally turned their heads though so I
| quickly snapped my visible light image with a DSLR in one
| hand on a tripod and scanned over the horse part with the
| thermal camera in the other, before patiently scanning the
| rest of the scene. The horses in the distance though still
| did move, as you can see in the separate thermal/visible
| images in the repo.
|
| I had to do a similar thing for the erupting geyser. 2 quick
| thermal shots in rapid succession for the eruption in one
| hand, DSLR in the other, then scanned the rest of the scene.
| Took about maybe 20 tries at least.
| [deleted]
| gandalfian wrote:
| Cunning. He took panoramas with thermal camera and simultaneous
| black and white photos and coloured the b&w photos with the data
| from the thermal camera. Interesting examples of insulation. I
| wonder how the result compares to the standard Flir auto blended
| images. Msx?
| brk wrote:
| This would be better than FLIR's MSX, which generally suffers
| from a lack of precise alignment of the thermal and optical
| images, particularly for shots with a lot of depth of field.
| systemvoltage wrote:
| Why are Thermal cameras lagging in resolution? Visible wavelength
| cameras can be had upwards of 50MP for $5k.
| rahimiali wrote:
| Visible wavelength cameras rely on relatively cheap CMOS
| sensors. CMOS processes have been squeezed for efficiency for
| decades to make, for example cheap DRAM.
|
| The technologies behind thermal cameras are very different
| because they need to be sensitive to wavelengths 10x longer
| than visible light (the silicon in CMOS is basically completely
| insensitive to light above 2 um, whereas thermal cameras need
| to image at ~10 um). The pixels are effectively microbolometers
| and rely on more exotic materials like Germanium.
| jzwinck wrote:
| Thermal cameras measure much larger waves (7-14 microns as
| described in the article), and their sensitivity to amplitude
| is high.
|
| A major limiting factor in camera sensor resolution is signal
| to noise ratio. It is well known that if you bump up the "ISO"
| (light sensitivity) to make photographs at night, you see more
| noise. The higher the sensor resolution, the smaller each
| photosite and therefore the less signal (fewer photons)
| captured in the short time of one exposure.
|
| Larger sensors can solve this problem but these are CMOS
| devices whose cost increases superlinearly with area (like
| microprocessors, see die yield). Most customers won't accept
| dead pixels.
|
| Economics is also a major enabler of kilobuck 50 MP visible
| light cameras, miracles though they are. Industrial users
| aren't going to re-buy all their cameras every few years like
| DSLR users do.
| jedimastert wrote:
| I wonder if lower-iso long-exposure thermals would be useful,
| or if it would get too "motion blurred"
| tpmx wrote:
| This is just slighly informed, please prove me wrong.
|
| The major market so far seems to have been tactical/military,
| so they have focused on framerates rather than resolution. And
| then the US blocked high framerates for civilian use...
| supernova87a wrote:
| As I recall, IR sensors are also much more expensive to
| produce, as in, 1Kx1K is already a very large array and costs
| thousands of $. So any ordinary consumer is not likely to be
| using something with very high resolution.
| giantg2 wrote:
| I agree. The median income in the US is $35k, and many of
| these things are 5-10% of that.
|
| I'd really like a monocular, but anything decent is very
| expensive.
| 0xFluegel wrote:
| The sensor needs a lot more energy. This produces two types of
| IR cams: actively and passively cooled. The passive cooling is
| easy to take around with you but only possible with a smaller
| sensor.
|
| As for the price per pixel: I don't know from memory.
| semi-extrinsic wrote:
| I think it's a combination of physics (wavelength is 20x larger
| than visual light, making optics and sensors trickier) and
| export control, as you could (literally) weaponize a high-res
| thermal camera to make an autonomous drone/missile targetting
| hot exhaust etc.
| deadw3ight wrote:
| That's sick! Brilliant and creative idea. Those shots look
| beautiful.
| brianjunyinchan wrote:
| Love the beautifully haunting perspective.
| cs702 wrote:
| Beautiful. Eerie. Great work. Thank you for sharing.
|
| Your images look almost like they came out of James Cameron's
| vivid imagination. If you had told me these were computer-
| generated images of Pandora at night[a] from the upcoming Avatar
| sequel, I would have believed it.
|
| [a] E.g., see
| https://www.google.com/search?tbm=isch&q=avatar%20pandora%20...
| osamagirl69 wrote:
| I have done a lot of work with high resolution thermal imagers
| and never seen any images that look like these so I was curious
| what was going on.
|
| >I also simultaneously shot a black-and-white photo with a
| regular camera and a wide-angle lens for comparison. I then wrote
| my own program to color the black-and-white photograph with the
| actual thermal data, using a false-color scale which you see in
| the upper-right corner of every image.
|
| Amazing drawings, but these are not actually thermal images.
| [deleted]
| dheera wrote:
| OP here -- I added a top-level comment with some more links. In
| particular you can find the separate thermal and visible images
| on the repo: https://github.com/dheera/iceland-thermal
| osamagirl69 wrote:
| Thanks for the clarification! This makes sense, the reason
| your images look 'off' is that the normal thermal pallets
| (such as the one in your colorbar) are typically a roughly
| constant (or at least smoothly varying) luminance with the
| thermal information stored in the chroma. Your images have
| that multiplied by the visible light image intensity which
| gives a very surreal effect. Fun stuff
| mmaunder wrote:
| Pure thermal would have been quite smudged. IMHO the B&W adds
| really nice context - and it sounds like it's not just a
| straight overlay, but he's recoloring the B&W pixels, which I
| think provides a crisper result.
|
| I'm curious what resolutions you've worked with, if you don't
| mind sharing. High frame rate thermal cameras (above 9hz) are
| ITAR restricted. Hi-res above 640x480 is not common on the
| consumer market and is restricted to embargoed countries.
| Cooled thermal cameras are restricted too IIRC.
| osamagirl69 wrote:
| The device we had was 1.3MP--rough the same resolution as the
| composite image discussed in this article. The camera core
| was expensive, but the lens actually cost more than the
| sensor. Yes it was ITAR regulated.
|
| As an example of what I would have expected, this product
| brief (not the device we were using, but similar) has a
| picture of the white house
| https://www.lockheedmartin.com/content/dam/lockheed-
| martin/m...
| schoen wrote:
| (That building is the U.S. Capitol rather than the White
| House.)
| semi-extrinsic wrote:
| That's the Capitol building though, not the White House?
| osamagirl69 wrote:
| probably - I have never actually been to DC
| mmaunder wrote:
| Thanks. Interesting link. I must admit I can't help but
| admire Lockheed's marketing with that whitehouse image.
| There's a not-so-subtle message in there.
|
| Sounds like super interesting work!!
| fpoling wrote:
| I presume that was with 16 bits per pixel, which is not
| available in consumer cameras.
| fpoling wrote:
| At my previous work I was involved with processing of data
| from 1024x800 cameras with 16 bit per pixel and nice optics.
| After proper calibration and trivial image processing they
| were not particularly blurry since they were able to resolve
| even tiny temperature differences.
| andreareina wrote:
| Don't commercial thermal imaging cameras also do a
| thermal/visible composite? Would those also not count as
| thermal images?
| smoldesu wrote:
| New Wallpaper Get!
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