Yet another cheap thermal imager incoming.. Seek Thermal

[efahrenholz]

@jaybeez,

Actually I didn't wait for a flat field. The reason the photo looks so noise free is because the palette is stretched past the max and min temperature. Basically its a low contrast photo. I wouldn't mind being able to manually set the high and low point for the palette, so I can see more of my surroundings that are close to the same temperature, rather than a gray image with faint changes. I realize the noise level on the sensor is pretty bad, but still, I'd rather have the options to have manual control over the camera parameters. I don't expect them to give us the option to change the averaging (it's a byproduct of limiting the camera to 9hz), but Seek needs to give us manual flat field control (shuttered and shutterless) and manual control of the palette stretch.

[efahrenholz]

I found this vid comparing Seek with Therm-app.  sorry if this is a not so smart question to ask as I don't have much thermal background (or anything else )  With future software revisions, does anybody think its posbile for seek to look similar to therm app? 

http://youtu.be/5FvVJE-qLhw

We could certainly get good images like that, albeit not quite as sharp. The problem is the process seek uses to digest the data off the sensor. They appear to be running a blur filter over the image. That ruins edges, reducing the apparent resolution. Rather than attacking the whole image, leave the data that's there and fill in the null pixels with the average of their 8 pixel neighbors. Since its already getting a five frame average, most problematic noise should be averaged out. Dead pixels are well, dead pixels. They look worse on low resolution imagers, so that's a compromise. Then finish the image with a good sharpen filter to improve edges further.

[Galaxyrise]

Here's a thermie of my cat. Really shows the detail the camera can achieve.

That doesn't look quite right unless it's an inverted palette... the eyes should be much hotter:

That is the "Black" pallet. Which is the inverse of "White".

In "black" hottest objects are darkest, so the cat looks as expected. I still think "Tyrian" is my favorite.

I agree with Amyk.  I do not expect the nose and the eyes to be the same value in a thermal image! 

[miguelvp]

I kind of agree look at this reference image from the web:


And the ones posted using the same palette.



Eyes too cold and nose too hot. Maybe you took it after the cat was rubbing on your and had the eyes closed. But they look open in your picture

[Fraser]

As a cat owner and having used my thermal cameras on them many times as a test subject, I can confirm that a cats eye area is always hot and the nose usually very cold by comparison. Other hot areas are their paw pads and their exhaust pipe (under their tail) 

With a 320x240 thermal camera I can always see fur detail in the image as well. This can be a good resolution and sharpness test but you have to remember that the SEEK is fixed focus so images will not be as sharp as those with a manual focus capability.

Aurora

[marshallh]

Yes the eyes are always one of the warmest areas.

[efahrenholz]

That's an interesting observation about Taz (my cat). I didnt consider that his nose was warmer than it was supposed to be. When I was watching him, I could see the cold air blowing out of his nose over his lips. Perhaps my taz is sick? I heard a sign of a sick cat is a warm dry nose. But I'm sure it's staying wet.

[Fraser]

I attach some pictures of Oliver that I took some time ago using one of my PM695's. They are nothing special as I have not tuned the span or anything. Oliver is sat on a hot water bottle in some of the pic's. My feet are also shown in one image as I often use them as a simple test source 

[Fraser]

Just a few E4 (320x240) pics for comparison purposes. Plaster dabs on walls are clearly visible but note that a reduced span is needed to increase the contrast.

[Fraser]

In case readers have not realised the significance of having control over a thermal cameras span and centre temperature. You can suffer very low contrast images when large spans are used. Small spans such as 10C, 5C or 2C require the user to fine tune the centre temperature for the target of interest but it permits greater detail to be extracted when working with scenes that have small temperature differential in the targets, yet also contain higher temperature objects that can fool a TIC into using a wider span and lose thermal contrast.

Some cameras actually use the terms "Brightness" for the Centre Temp and "Contrast" for the Span. This is the effect seen in the image so I can understand such terms being used.

For my work I am often operating with less than 5C span but you need a decent low noise camera for such spans as the noise really starts to show at such settings.

[callipso]

The cat does look a bit visible-spectrumy...

Also anyone owns both a TIC and a guinea pig? I'd like to see that...

[miguelvp]

The cat does look a bit visible-spectrumy...

Also anyone owns both a TIC and a guinea pig? I'd like to see that...

Guinea pig:
http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/guinea.html

Others:
http://coolcosmos.ipac.caltech.edu/image_galleries/ir_zoo/zoo.html

[Fraser]

Cool site 

Thanks for the url.

Aurora

[callipso]

OOOOEEEEEEEEE SO CUTE!

gotta loove guinea pigs

[eneuro]

The cat does look a bit visible-spectrumy...

Cat simply could sleep, than many people reported even without thermal cameras that his nose will be warmer than usual and it doesn't have to mean that it is sick 

Simply with this Seek Thermal toy without adjustable focus forget about thermal image quality 

To get decent sharp edges one needs manual focus like in this SKF TKTI 21 (160x120 pixels ONLY?)

Seek Thermal in USB dongle version is too small, but quality means more weight and volume, so do not expect too much from this toy, unless one will make some DIY version with own software.
Just looked at SKF TKTI 21 manual and of course one gets PC image analysis software on CD not via doggy app stores which try to limit downloads to part of internet 

Even in toys low power laser pointer should help to easy find what we are looking for, so Seek Thermal without laser... simply it looks like a toy for bigger boys 

[efahrenholz]

The cat does look a bit visible-spectrumy...

Also anyone owns both a TIC and a guinea pig? I'd like to see that...

I assure you it was a real shot through the camera. And it wasn't post processed outside the seek app.

[Fraser]

@eneuro

Not sure I can agree about the focus statement.

Cameras that do not have manual or auto focus use a fixed focus lens that provides adequate focus over a large depth of field (due to lens design). The E4 has such a lens and copes well in many scenarios. Close up lenses are used to provide detailed images of PCB's etc. I will agree that the manual and auto focus TIC's that I have do provide pin sharp images at all distances within their spec BUT they do need me to keep adjusting the focus, unlike on the E4.

Also at 320x240 or 160x120, the resolution limits the sharpness of the image anyway. Its not exactly HD 

IMHO it is way too early to call the SEEK a "toy".

[callipso]

The cat does look a bit visible-spectrumy...

Also anyone owns both a TIC and a guinea pig? I'd like to see that...

I assure you it was a real shot through the camera. And it wasn't post processed outside the seek app.

I don't think there's any reason to doubt you, that was a mere observation of mine..

[efahrenholz]

I prefer the look of a black hot palette, seems to bring out more details in warm objects. If I'm looking at cold stuff mostly, I'll switch to a white hot. The colored palettes have never really appealed to me.

[callipso]

I think the security/surveillance people use the blackhot palette. The whitehot feels just so much more natural to me...

[RAWebb]

Close up lenses are used to provide detailed images of PCB's etc.

I've put up a simple holder for the 20mm ZnSe lenses over at Thingiverse. It's just a friction fit which depends on the asymmetry of the camera face to hold it in place, but it seems to do the trick. Should do well enough to keep handy in the toolbag. http://www.thingiverse.com/thing:525605

[miguelvp]

Close up lenses are used to provide detailed images of PCB's etc.

I've put up a simple holder for the 20mm ZnSe lenses over at Thingiverse. It's just a friction fit which depends on the asymmetry of the camera face to hold it in place, but it seems to do the trick. Should do well enough to keep handy in the toolbag. http://www.thingiverse.com/thing:525605

Thanks! don't have a 3d printer but I know at least 3 at work that do

[efahrenholz]

I think the security/surveillance people use the blackhot palette. The whitehot feels just so much more natural to me...

Ok, I guess i'm starting to fall in love with the tyrian palette now. It looks pretty good.

God, i'd give anything to turn off that blasted automatic flatfield calibration and take a through lens one. They could have made a simple flip up cover on the outside of the body. Want to do a calibration? Flip it up and press a button on screen. Bam, calibrates the field against the lens and sensor. My images look much cleaner when i do the magnet trick. But its short lived.

Weird thing about flatfield calibration...if i do the magnet trick, obviously it takes whatever it sees and uses that to sub out each frame. But on the very next flat field where i let the shutter work, a ghost image of the last flat field (like hot objects) is still present, but less. l think Seeks software is averaging flat fields. A bug?

[jaybeez]

Close up lenses are used to provide detailed images of PCB's etc.

I've put up a simple holder for the 20mm ZnSe lenses over at Thingiverse. It's just a friction fit which depends on the asymmetry of the camera face to hold it in place, but it seems to do the trick. Should do well enough to keep handy in the toolbag. http://www.thingiverse.com/thing:525605

have any pictures you've taken with this setup?

[miguelvp]

There is one on the link with and without