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A First Test with my GSENSE2020BSI Camera

Filters UV Camera UV Lens
47 replies to this topic

#41 Stefano

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Posted 20 November 2020 - 04:32

I will check later on the original images, in the midtime I looked at a bunch of other images from this camera I saved on my phone, and they are all 5 mm. That should be the focal length at the minimum zoom. I looked at a fully zoomed-in image and there the focal length is 20 mm. So my camera does between 5 and 20 mm, and the images above should be 5 mm.

Of course you have to take into account the small size of my sensor. 5 mm on a typical sensor would be super wide angle.

I found the images on my phone. Yes, 5 mm (both).

Edited by Stefano, 20 November 2020 - 05:06.


#42 WiSi-Testpilot

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Posted 20 November 2020 - 08:30

View PostStefano, on 19 November 2020 - 23:29, said:

Is this without filters (full-spectrum)? For one second of exposure, that's not bad at all. Here is what my camera can do with 60 seconds of exposure:
https://www.ultravio...attach_id=17275

https://www.ultravio...attach_id=17276

Your sensor looks grainy, in a good way. It reminds me of paper (I never shot film, but I know that film, especially high ISO film is grainy, but it isn't like the noise in a digital camera, it is good noise).

You may try subtracting a dark frame to attenuate this, assuming it is noise and not light pollution or haze in the sky.

Stefano,
thank you for the information and the links.
It's a full spectrum image. First I tried my 313 nm filter, but it didn't work.
I took the picture in our garden. There was of course light pollution and also haze in the sky. The Milky Way was not visible with the naked eye. So I'll do it again when the sky is clear.
Furthermore, the camera is very unwieldy. I'm trying to build a more mobile unit right now.
Best regards,
Wilhelm
Attached Image: Kamera&Notebook.jpg

Edited by WiSi-Testpilot, 20 November 2020 - 08:59.


#43 dabateman

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Posted 20 November 2020 - 12:01

You have a ghost cable in that image.

I like the star image. It has a nice feel to it. Too many of our stuff these days is too clean.

#44 WiSi-Testpilot

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Posted 20 November 2020 - 14:59

Thank you.
I bought a small Win10 PC (Orbsmart AW-08S)
and a shorter ghost cable for the new setup.

Attached Image: Mini-PC-Win10.jpg

#45 WiSi-Testpilot

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Posted 23 November 2020 - 09:46

I would like to take UV-B images in daylight at 300 nm. Therefore I bought a 300/10 nm bandpass filter.

Attached Image: 300nm_bp-filter.jpg


The question is: is UV light available at 300 nm now in November?
As a test object, I use our terrace roof. A part has UV protection, a part has not.

Terrace coverage recorded with the Full Spectrum Alpha 6000 and the Baader U-Filter.
Attached Image: 13-11-2020-DSC08405.JPG


Terrace coverage recorded with the 2020BSI camera, 300 nm and 313 nm filter. At 300 nm, the UV protection is hardly to see.
Attached Image: 300nm&313nm.jpg


I also tested the influence of glass at 300 nm. It is a double-glazed window.
Attached Image: Glas-300nm.jpg

All images where made at the same day.
It seems, that there is a small amount of 300 nm UV light superimposed with the leakage of the filter.
Best regards,
Wilhelm

Edited by WiSi-Testpilot, 23 November 2020 - 09:47.


#46 Stefano

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Posted 23 November 2020 - 12:43

If you have some Hoya U-340/UG11/ZWB1 glass, try to stack it on the filter. Depending on where the leak is, this could help.

#47 WiSi-Testpilot

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Posted 23 November 2020 - 23:04

Stefano, I don't really want to use glass filters. When the sun is shining strongly again, I will repeat the test.

#48 WiSi-Testpilot

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Posted 24 November 2020 - 10:54

Back to the stars:
this is a winter assignment.

Edit: I've added the positions of two nebulae.

Attached Image: Vorlage-Milchstraße.jpg

Edited by WiSi-Testpilot, 24 November 2020 - 17:52.