Hti HT-301 384 x 288

[RBsonic]

Also, what is their framerate? Is it <9fps or is it more like 30fps or 60fps?

It's 25fps. But it depends on your phone. I have old phone and sometimes I get 23-24fps
https://www.eevblog.com/forum/thermal-imaging/hti-ht-301-384-x-288/msg2814034/#msg2814034

[Ben321]

Is the HT301's VOx microbolometer actually 384x288? Or is it half that resolution, and then upscaled in the device's firmware image processing code?

[svgurus]

Is the HT301's VOx microbolometer actually 384x288? Or is it half that resolution, and then upscaled in the device's firmware image processing code?

Funny question) Its is an imager with detachable lens, you can see sensor size(or silicon/germanium cover, if you are tedious to that degree). With 17m pitch and 128*192 resolution, size of that nice looking mirror would be twice smaller. I also have 2 other imagers with that 384 resolution and 17m pitch, as far as i can remember the size is about equal.

[jiang_thermal imaging]

HT-301 uses infiray sensor 384*288, There is also Infiray T3S with same resolution, quality is better, but price is good.

[alexwhittemore]

UVC thermal video capture works great with the HTI-301, but when connecting the T3s to the system or any other PC, it is recognized as a UVC device, but I only get a green crumbled video, objects are barely visible. So, if anyone in here can give me a hint how to get the T3s to the same behavior and functionality as the HTI, I would be really happy!\

Sounds familiar. A buddy and I are working on some PC-side software to pull thermal video from the camera live (an HT-301, I mean).

The HT-301 connects via UVC, and has two modes. In the default mode, it outputs YUV data in greyscale, with two rows of pixels across the bottom encoding the hottest temp+coordinates, the coldest temp+coordinates, and a few other things. In other words, you get a grayscale image with no thermographic data, and absolute calculated temp extremes with coordinates.

In the second mode, which you enable by sending a UVC zoom command (or something like that, I forget), you get pixel data where the lower two bytes are 16-bit temperature data for each pixel, that requires some calculation involving ambient temp, humidity, and range, to massage into degrees C - in other words, absolute thermographic data, some assembly required. In this mode, the video when interpreted as YUV looks like a green blobby mess, where you can of course make out the details of the image and scene, but the green shades make no obvious sense.

It sounds like maybe the T3s has the same readout mode, and defaults to that.

Now before you get your hopes up - the software I'm working on is quite nonfunctional at the moment, and our calculation to go from pixel data to temp is verifiably wrong, so there's a long way to go

[thikone]

Got myself HT-301 after considering Seek Thermal CompactPro for very long time. After all, 25 Hz and more detailed image swayed my decision to spend more money.

At first, my Google Pixel 4a was crashing and rebooting when connecting the cam, right after granting permissions for official app. Apparently, it is known issue with late builds of Android 11 for Pixels, connecting any USB web cam would cause that (https://issuetracker.google.com/issues/183716542). Early builds of Android 11 and Android 12 seems to have it working. Downgraded to Android 11 RQ1A.210205.004, Feb 2021 which works now (don't Android 12 look).

Also thanks to this blog bough II-VI ZnSe 50.8 20mm lens and 3d-printed a holder for it for macro mode. One reason less to stick to Seek Thermal for which people sell such lens.

And I can connect it to PC with Win10 and use system Camera app to see white-hot picture from it (with some color rows at the bottom that are used to convey some additional data). It can also record videos or photos.

I like the official HTi app for Android better than ThermalViewer that I tried too.

However, there is one thing that is nagging me - static noise. When the whole surface is about the same temperature (no huge contrast) then I see that upper third of the image is 1-2 degree colder.
Like on this video:
https://youtu.be/Lu01O4SYT_g

Didn't see such artefacts on other people's videos. Should I return it and order a replacement?

[MegaVolt]

Didn't see such artefacts on other people's videos. Should I return it and order a replacement?

Sounds like a calibration issue. Do you hear the sound from the curtain? Manual start of the calibration has an effect?

[thikone]

Didn't see such artefacts on other people's videos. Should I return it and order a replacement?

Sounds like a calibration issue. Do you hear the sound from the curtain? Manual start of the calibration has an effect?

Interstingly enough, it only appears after like 3 minutes of working. Calibration does help a bit, but no near like it was right after cold start.

[Bill W]

In that case it is internal parts heating up that are beyond the shutter, or possibly the shutter itself.

Having a cold low contrast scene is making it look worse too.  You need to think more in terms of thermal energy than simple °C

Bill

[thikone]

In that case it is internal parts heating up that are beyond the shutter, or possibly the shutter itself.

Having a cold low contrast scene is making it look worse too.  You need to think more in terms of thermal energy than simple °C

Bill

But is it also like this for others, who has HT-301?

[MegaVolt]

But is it also like this for others, who has HT-301?

I don't have that effect. The picture has the same temperature.

[thikone]

Ordered a second one. Was hoping it will be perfect. But no... Second one has opposite problem. Upper quarter is always about one degree Celsius hotter.

Visually, it is somehow more appealing than the first one, that had upper quarter always cooler. But I don't want to be put up with lesser than average performance for this price.

When there is something very hot and very cold in the frame then it is less obvious, unless you check the temperature measurements. Here is an example of that:

https://youtu.be/hY4X6TohmA8

On white hot color schema it looks like this:

https://youtu.be/4UmvindkMcg

Manual calibration doesn't help much. I can see that it tries to compensate for it but only slightly and it is still visible.

Nobody else has notice something like this with theirs HT-301?

[superoni]

On Android 13 (Pixel 7), the HTI Image app is only partially working. Images work, but video recording will crash the app. Unfortunately, there doesn't appear to be any compatible alternative app for Android 13. ThermViewer is not supported on Android 13. Please let me know if there are any workarounds.

[Angel1024]

On Android 13 (Pixel 7), the HTI Image app is only partially working. Images work, but video recording will crash the app. Unfortunately, there doesn't appear to be any compatible alternative app for Android 13. ThermViewer is not supported on Android 13. Please let me know if there are any workarounds.

you can try inficam, i attach it. It for t3s but same hardware. Developer discord link is here https://discord.com/invite/GwsnAbwp7n

[NinetySix]

I'm not saying that you're not having trouble with thermviewer on your P7, but I can use thermviewer just fine on my P6A on Android 13