Using my Microsoft Life HD webcam for planet images

[jondjon]

Hi all. I'm trying to start taking images of the planets through my 10" Dobson using my modified Life HD webcam. I did the modification myself, stripping down most of the external components of the webacm and then placing the webcam unit into an old barlow lense tube (lenses removed) so the webcam would easily fit into the eyepiece of the dobson. This is where it goes wrong. When I view the webcam image using SharpCap I just get a view of the dobson tube! From what I understand from reading other posts on using a webcam, the webcam replaces the need for a lens (although a barlow can be used to magnifiy more if needed) so I was expecting to see an image like that on my SharpCap view. If I attach the webcam to a 25mm lense and then place that into the eyepiece I don't get the view of the tube but what I you would normally see through the 25mm lense. What am I doing wrong?!! (hope it all makes sense). Thanks for any help. Jon

[basher0010]

hi there

do you still have the camera lens attached to the webcam if so you will be seeing an afocal image on the screen if you have removed the camera lens then the view will be prime focus and wont require the eyepiece..

[gary1968]

hi there

do you still have the camera lens attached to the webcam if so you will be seeing an afocal image on the screen if you have removed the camera lens then the view will be prime focus and wont require the eyepiece..

+1, what he said..... make sure the lens cell has been removed from the camera exposing the chip.

Gary

[JamesF]

Exactly that. And once you've removed the camera lens the camera sensor is exposed to the elements, so it's a good idea to screw a clear or IR filter into the end of the new housing to keep dust out.

James

[Gina]

Yes, an IR/UV blocking filter is a good idea and essential for others with a refractor (like me) to avoid IR and UV wavelengths which focus at a different point from visual wavelengths and would produce blurred images.

[JamesF]

I reckon a filter is required regardless of whether you have a refractor or reflector, Gina. Even if the (reflector) telescope itself brings (say) IR to the same focus point as visible light, the atmosphere has already got in on the act, so the different wavelengths will still be shifted. It clearly happens for visual light even when imaging with a reflector, so it must happen with IR too, no?

James

[Gina]

I think you're probably right.

[WakeyTiger]

Guys, I've a query about the LIfecam conversion - in the process of removing my AF lens, I slightly creased the thin plastic film which is covering the chip. Can this safely be removed, or is it required - as I now have a small 'blur' in the corner of all my images...

[Monki]

I have minute black spots on my lifecam sensor...just dust or LED fragments from when I crushed it I guess..but if there is some film I can peel off to clear this I might do that. I used to clean CPU cores with turps/spirits.....i wonder if you can use this to clean cmos sensors...

How was it you came to catch the sensor and lift some film? Just catching it with the lens?

Think im going to check this out tomorrow!

Edit: in regards to filters...I can say adding a baader Neo ir/uv cut improved my image quality by reducing the red/purple tint. Sharpness may have been improved, but tbh the webcams 4mm sensor is really testing my 60mm anyway hehe.

Sent from my GT-I9100 using Tapatalk 2

[graham72]

Hi, i am new to this site and trying to attach my Logitech Web Cam to my Skywatcher Explorer. i have followed instructions found on You Tube, but all i am seeing is the inside of my Telescope also, i need help....... and fast:(

[JamesF]

Sounds like you haven't removed the lens from the camera.

James

[jondjon]

Thanks to all for your replies. Took the lens off the webcam and down to the chip. Works fine now. Thanks again.

[nytecam]

It clearly happens for visual light even when imaging with a reflector, so it must happen with IR too, no?James

I was under the impression that IR is deviated less, due to its longer wavelengths than visible, enroute through the atmosphere. Unless blocked IR can spoil colour balance for purists:cool:

[JamesF]

Less than what?

Angles of refraction may not always be frequency-dependent, I think, but in the case of our atmosphere I believe they are. If we take "green" as our reference point for the sake of argument then there will be a continuum of angles of refraction depending on wavelength. Compared to green, blue will be refracted one way and red the other (which is "more" than green and which is "less" may be for the observer to work out, but in the case of planets and stars I guess we'd all find it fairly easy to agree. However, IR must surely be refracted "further" from green than red? It may be that the angles of refraction aren't proportional to the wavelengths measured from reference point so the increase in wavelength doesn't give you a proportionally large increase in refraction angle. I'm struggling to remember my O level Physics now

James

[nytecam]

I was referring to less disturbed seeing conditions in IR compared to visible wavelengths !