TheSkySearchers

I apologize if this is a stupid question but I've been wondering if any amateur astronomers play around with thermal of maybe infrared imaging through their telescope. I'm not talking about something as sophisticated as what the James Webb Telescope is using. Do they make a small thermal or infrared cameras that can attach to a telescope?

I haven't done any AP nor do I know much about it and I'm probably a few years from wandering into that area but I was just wondering about the possibilities of using our little Telescopes for some kind of thermal imaging.

IR equipment would not be useful, but night vision works like a charm.

https://www.televue.com/mobile/TV5_page.asp?id=36

That is VERY cool. Also VERY expensive.

Flyhigh7 wrote: ↑Mon Mar 04, 2024 4:29 pm That is VERY cool. Also VERY expensive.

I know right!? I hope the price will go down a bit with time.

Yea! that video of the Orion Nebula was even picking up the black dust of the cloud. Impressive.

Ive done allot or IR photography with film. Today some astro cams are great for IR sensitivity and a IR filter (720) not much so you can get into it for around $500.
Never done Thermal.

If you have an IR sensitive camera wich most cmos cameras are nowdays and an 850nm Ir pass filter and attach them to a f2 or faster lens say like a 11mm objective and a 25mm fl...

You can see the Sun shine right through the blackest of blackout curtains and the view makes them look thin as a wedding veil with the fabrics complex interweavings and stitchings even becoming viewable.

If a person walks close by the window outside on a sunny day, you can see thier shadow easily. Black out curtains are almost see through beyond the visible spectrum I found out.

At night it works ok and for extended views an IR iluminator or Ir flashlight can extend the range of what becomes visible but its way more fun with strong Ir sources and or in daylight.

I have often imaged the Sun through my solar wedge using the 850 or 685nm Ir pass filters and the Ir pass filters do an excellent job there too...

You need to differentiate between infrared imaging and thermal imaging. I say this because the near infrared (NIR) imaging we do through glass can only be done with wavelengths shorter than 1000nm. This we could call the top end of the near IR spectrum (780 to 2000nm). Once you get longer than around 1500nm or 1.5 microns glass becomes more and more opaque to thermal images. This is why thermal sensors are made from metal. If you were to buy a FlIR ONE thermal camera attachemnt for your iPhone you would be imaging wavelengths between 8000 to 14000 nm or 8 - 14 microns. At these wavelengths you could hide behind a large pane of glass and be competely invisible to the thermal camera.

So a traditional telescope is not well suited at all for thermal imaging!

The water vapour in the Earth's atmosphere very effectively filters and blocks IR. So deep sky IR is a waste of time regardless of the sensitivity of your camera.

High altitude observatories eg Mauna Kea (4000m) Atacama (6000m) can do some IR but at normal altitudes you won't get much, except perhaps the sun.

In the 1970's, my astronomy mentor used to use his 12" cassegrain to measure visual wavelengths of B[e] type flare stars. He collaborated and simultaneously coordinated the observing runs with the Parkes 64m radio telescope and the Mt Stromlo 74in reflector doing IR. Mt Stromlo is about 900m altitude and a 74 in telescope doing IR from that altitude only had sensitivity to IR comparable to a 12" optical wavelength telescope.

Scaled down, a 12" scope doing IR might only have IR sensitivity comparable to a 2" scope. Maybe go to Pike's Peak and observe from there?

Joe