réalisation spectroscope

[Robin Leadbeater]

Hello Sebastien,

Have you seen my junk box spectrograph?

http://www.threehillsobservatory.co.uk/ ... opy_19.htm

This uses an eyepiece as a collimator and camera lens ans standard adapters. It uses a low dispersion 200l/mm grating so the angle is small enough for everything to be in a straight line. With your 600l/mm grating you would need a wedge prism to keep the beam straight (like the ALPY). You could also add a slit but the problem then is putting the star on the slit, focusing it and guiding is difficult. You really need to add a guider module once you add a slit

Cheers
Robin

[Sebastien Berriot]

]Hello,

Thank you Peter.
What is the name of the adapter and where to buy it ?

[Robin Leadbeater]

]
What is the name of the adapter and where to buy it ?

It is a 55mm to 42mm (T2) step ring. I bought it here
https://www.ebay.co.uk/itm/Male-55mm-to ... 0720920082

Cheers
Robin

[Sebastien Berriot]

Hello Robin,

Thank you for the site.

In this configuration with APN,

what is the name of the adapter(s) after the T2 ring ?

what is the référence of the oculaire ?

where to buy the adapters and the oculaire in the site not expansive ?

[Robin Leadbeater]

The parts were from my "junk box" collection. I think this is the eyepiece
https://www.teleskop-express.de/shop/pr ... meras.html
I cannot find the exact T2/1.25 adapter but perhaps this could be used
https://astronomy-imaging-camera.com/pr ... er-adapter

Cheers
Robin

[Sebastien Berriot]

To finish,

how do you install the star analyser 200 ?

[Robin Leadbeater]

To finish,

how do you install the star analyser 200 ?

It screws into the centre of the T2 male/male adapter

https://astronomy-imaging-camera.com/pr ... er-adapter

[Sebastien Berriot]

Hello robin,

if I summarize for this spectro it is necessary in order from the photo lens

1 ) adapteur 55m / 42 mm

2 ) adapter T2 male / male

3) in the adapter T2 male/ male there are ring T2- 1,25'' with the star analyser 200 mm

4 ) adapter T2 female/ female

5 ) eyepièce 40 mm

It is exactly ?
Sébastien

[Robin Leadbeater]

The T2/1.25 inch adapter is not the same as mine. I just used what I had in my junk box. If you are buying all the adapters I can suggest a simpler set

Camera lens with 55mm female

55 male - T2 female

T2 male - T2 female extension tube
https://www.teleskop-express.de/shop/pr ... ength.html

T2 male with 1.25 inch hole for SA200 mounted inside the extension tube
https://www.teleskop-express.de/shop/pr ... lters.html

40mm eyepiece with T2 male

Cheers
Robin

[Sebastien Berriot]

Robin,

Do you have a exemple of spectre with this configuration (APN) ?

thank you
Sébastien