Forum der Vereinigung der Sternfreunde

Hello everyone!

I got an adjustable slit with a lens on it.The lens seems to be 140mm.
I am thinking of using the whole set(slit+lens) for a simple prism spectrograph.I guess that the lens could play the role of the collimator.
Has anyone used such a slit before?

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Everything is Mathematics !

Hi Alexandros! I don't think so. The collimator would then have an effective aperture of the slit width. Maybe the lens is a focal reducer.

Thomas

Hi,

Sorry I can not See anything on the pics.

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Daniel P. Sablowski

https://www.kunstmann.de/buch/axel_hack ... 42000/t-2/
https://dpsablowski.wordpress.com
https://github.com/DPSablowski
https://www.aip.de/mitglieder/dsablowski/

A lens on the same place the light is focused is suspicious!.. It sounds like a field lens!
In other words, it is likely to be of use for non stellar targets, or where an image on a large slit is much off center.. The lens should help keep the incoming light from "the sides" going into the same place ans "the center" light (into the colimator and later well parallel into the grating).. Something like that.. It is likely a considerably large slit!..
It is a converging lens, is it not?

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Fil.

Hello Alexandros,

I cannot see a use of this slit in the focus of a (private) telescope. It is not reflective and only constructed for broad slit widths. I think it's a secondary slit of a monochromator or such a similar apparatus.

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Herzliche Grüße / best regards

Lothar

https://lotharschanne.wordpress.com/

Hello everyone

thank you all for the input.

Daniel i think that the lens is best seen on the third picture.

Filipe this is a converging lens.


Mr Lothar I have seen spectrographs with such a slit.

http://www.astrosurf.com/buil/us/loris/loris.htm

It is not the most convenient way but I'd like to give it a try.
I already have a low resolution spectrograph with a reflective slit,so now I am just experimenting.

You all got me into (good) thinking with your input.
This slit was for laser experiments, so probably it was the output slit.
I also have another adjustable slit with no lens attached to it,so I will have to use this one.


Thank you all for your feedback

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Everything is Mathematics !