First starlight for my new echelle

[Joan Guarro Flo]

Hello all,

With Toni Jové's help I've built one replica of the Tim's echelle, I'm showing now here the first results of the sky.

It's the NOU_T echelle, I've surprised to the long dynamic range of this instrument from 3980 Angs. to 8760 Angs. Although these results will be improve..

My intention is to use this device to R=9000 or R=7000 for arrive to little shining stars and also it's possible for telescopes from 20 cm. forward.

By the way, the telescope trip from Antares /Del Sco to Vega/P Cyg, ( 80 degrees and posture change ), it's represented one differential flexion in the ccd spectra image ecual to X=1 pixel, 9.08 microns and Y=3 pixels, 27,24 microns. I like this result.., at the moment.

From here I ask help to all, specially to Christian, author of ISIS, I have some doubts and little problems with stars data reduction. Certainly I use an old ISIS version. I don't know what I'm doing badly.., I don't know how to make the new ISIS versions are working well. You may see some these problems in the pictures. Others ones I would explain them later.

Friendly, Joan.

[Joan Guarro Flo]

Hello James, hello all,

With Tim Lester's indications and these scketchs and with Toni's help I done NOU_T echelle. In Catalan language NOU is equals to NEW or NINE or NUT, it depends..is ambiguous. The "T" is for Tim and also a bit for Toni Jové who make the mechanical parts.

Tim's project is simple and compact and really stable, the philosophy is take a echelle more accesible to observers, so it's mirrors sistem are very better than my MUSSOL or LINX.

Actually NOU_T has R9000 with a Nikon 85mm. f/1.8 but some people have told me if is may make a R5000, really it's possible R6000 with one Voigtländer 50mm. f/1.5 aspherical lens, times ago I sent R6000 graphics to some analistics with de same good results than R10000 or R14000, the advantage is the acces to more weak stars. One problem for it, is that ISIS don't recognizes some very important Orders with a very good Voigtländer 50mm. F/1.2 aspherical lens, I don't know if C.Buil would want say something about it.

I don't know NOU_T + ISIS behavior with a Voigtländer 58mm. F/1.4, I don't have any it.

I think Toni Jové will be enjoy to help to everyboby making the hole in the mirror, building the mechanical parts or whole echelle, with a very very reasonable price, he speaks English, his address is, tonijove@outlook.com.

I hope you like all it.

Cheers, Joan.

[Christian Buil]

Joan, many thanks for the detailed description of your new échelle spectrograph.
This achievement is really beautiful!

An important element is the ability to drill a aluminized mirror... The use of a concave mirror for collimator
function is also essential for reduce the chromaticism of the whole.

I have some questions Joan :

- I'm surprised you can go so far in the infrared using a photographic lens (a good new!).
Do you trace of chromaticism in this part of the spectrum by using your setup?

- It is not easy to find calibration lines in the infrared, apart argon lines. You have
not encountered any difficulties for precisely calibrate infrared ? Also, argon IR lines are very intense,
you have not encountered saturations problem ?

- The optimal adjustment of order recovery is always a long and difficult task.
I think the noise increase in the overlay areas comes from a bad definition of merging wavelength. Did you use
the tool "Wavelength order limits evaluation" to generate the def_lambda file (I recommend a 15% overlap) ?

- I am curious to see images (2D spectra) of tungsten lamp, of RELCO lamp and
of a typical star. Can you display these ?

Christian

[Joan Guarro Flo]

Bonjour Christian,

Yes, we had several test with different drills before make the definitive hole on the flat mirror, fortunately Toni Jové has a milling machine, now he can do a hole and with different diameter in almost to all inclinations. The commercial metallic coating it's usually very hard, I did a lot of work to remove the aluminized and quartz coating from Meade newtonian mirrors to improve their parabola.

Really I'm the first surprised, the old version Nikon 85 mm. f/1.8 it has an aspherical lens and it correcte very well the chromatic aberration and coma, althought you need to a compomise focus situation if you want the most possible Orders because remains a bit residual aberration. However with a tungstene 3500K I think few sometimes it's possible one range from 3835 to 9390 Angs., ( Orders 57 to 24 ), in an ideal situation..The other hand, I unknow why Tim doesn't get this results, he has the same Nikon than me, is possible he has a bit collimation error or CCD inclination, really I don't know about it.

R. Walker, P.Berardi and M.Dubs helped me in infrared lines, in these Order hvae some emission lines the work it's a good identification of them, those are actually results. It's a job to do.

Blaze function correction...
Order #24 : RMS = .4100 - Nb. lines = 6 Order : 24 (Lambda1, Lambda2) = (8980, 9393)
Order #25 : RMS = .4694 - Nb. lines = 7 Order : 25 (Lambda1, Lambda2) = (8628, 9009)
Order #26 : RMS = .0938 - Nb. lines = 9 Order : 26 (Lambda1, Lambda2) = (8304, 8656)
Order #27 : RMS = .0100 - Nb. lines = 7 Order : 27 (Lambda1, Lambda2) = (8002, 8329)

Thanks, I will use this 15%

I have some questions too, Christian,

I use ISIS versions 5.9.0 and 5.9.2 but ISIS newer versions broken when I try to reduce my data. What am I doing wrong ?

I don't know why, ISIS don't save Orders 25 and 24 but they both are in files _*_ **_full.fit.

Of course, I always getting graphics of stars but always far of the balze zone, and the flat**_dat files are very asymetrical, if I try centered to blaze zone ISIS has breaking. I don't undestand why.

I left here for you and for all, https://drive.google.com/file/d/1xROqUT ... sp=sharing , two VEGA observations and a CALIB folder it's day 20190809 is better than day 20190816.

Cordialement, Joan.

[Joan Guarro Flo]

Hello,

Everytime NOU_T and myself are knowing more well each other. He is very sensitive in his optical collimation, but his mechanical structure is hard, strong, stable and reliable.

 I show here the last CHECK2, ( 3974/9393 Angstroms ), just missing to get to ORDER 56, ( 3904/9383 Angstroms ), if that were possible, we would see the CaII H&K emission and the Calcium Triplet  in the same graphic . Someone idea for it ?

This November has unaccustomed bad weather here and there's held back in douane a Samyang 50mm. 1.4 to try to give NOU_T more light ratio.
Patience, Joan.

[Joan Guarro Flo]

Hello,

I received this picture from Toni, you can see in it five boxes of guide and calibration lights for the 5 new NOU_T, one of them is for Sta. Maria M. telescope.

I hope it like you. 

Joan.

[Hamish Barker]

wow, is Toni going into series production? if so, that would be awesome!

[Joan Guarro Flo]

Hello Hamish,

At the moment, Toni makes five NOU_T,  I already said that one it's for Sta. Maria M.,  and I think, that the others four will be for anyone who wants to of it.

The mechanical parts are in the middle of the manufacturing process now.

Joan.

[Joan Guarro Flo]

Hi,

After some personal considerations of C.Buil to me, about some errors in  Be star graphics made with the NOU_T, I've decided  change there both mirrors with dielectric treatment for others two with the aluminized treatment, the one of a lifetime.

I have too change the tungstene lamp for a OSRAM 64261 30W 12V. 3300K. And reduced these observations with the ISIS.5.9.3, with "Funtion de blaze lissée", "Cosmic rays filter" and "Order merging adjustment"  active.

The current equilateral prism has a Antireflective Coated I unknow if that has some negative effect in infrared or ultraviolet wavelengths....,  someone may tell me something about it ?

At the moment, I tink that the results have improved, I leave here some graphics.

Cheers, J. Guarro.

[Joan Guarro Flo]

Hi,
With one little modification in the NOU_T echelle I've been able to arrive to one wavelength range from 3771.5 to 9387.9 Angstroms.

I know that in the two extremes, the graphics are imprecise but I've been able to consolidate the Ca H&K lines in the violet and the Calcium triplet in the infrared.

Cheers, Joan.