Forum der Vereinigung der Sternfreunde

Hi,

OK, I had 2 imaging sessions of WR 134 with my modest equipment being an AstroTech 8" RC f/8 (f/5 using a reducer) on 15th and 16th of December 2011.

Spectrograph is LISA with 300lines per mm grating, 35µ slit and a QSI20i CCD cooled camera.

Resulting dispersion is 2.949Angström per pixel.

On 15th I made a serie of 6 subexposures of 600s and on 16th I made a serie of 2 subexposures of 1800 seconds. So I really do not know if the profiles are comparable.

Run of 15th '2011-12-16T02:45:04' /UT of midpoint of exposure


Run of 16th '2011-12-17T01:36:36' /UT of midpoint of exposure


Below my 2 profiles as *.dat file
http://astroforo.net/astro/rspec/wolfra ... 111215.dat
http://astroforo.net/astro/rspec/wolfra ... 111216.dat

Comparing the profiles at 5411A and 6562A I see some differences but they could be very well noise differences between the 2 different subexposure stackings

Comparison of the 5411A area Red=20111216 Blue=20111215


Comparison of the 6562A area Red=20111216 Blue=20111215


I know my setup is by far not big enough for this WR134, WR 135 and WR137 campaign but just reading the messages abou this campaign has been very interesting for me and has made me think about changing my imaging and venturing into very long exposure times and I see it pays out to having gone this route.

For me as a beginner a very interesting exercise.

Maybe in the next days I can make some consecutive profiles. Yesterday I had clouds all night and WR134 when I can start imaging is only 1.5 ~ 2 hours visible until it sets behind my Observatory horizon.

Thanks for reading and looking

_________________
Grüsse Rainer www.rsfotografia.com

Don't be too modest, Rainer! Your spectra are very nice and we all can learn from them. One can nicely see that both lines are covered by only some pixel. So, it would be very difficult to see sub-features of very low contrast moving through the line peak. That is the reason why we need higher resolution and contrast.

But again, with those observations we can see what is necessary for the campaign itself and we learn from them. Marco Leonardi already made this point and I fully agree with him (thank you Marco!). Even if some individual data do not show sufficient quality, we all can convince other amateurs that they can deliver interesting stuff.

Go ahead, Thomas

Hi Thomas,

Thanks at least my tests are good for something.



Hopefully I get a row of clear nights and so I can do some more with longer exposure times.

Would it make sense to do a single 1 hour exposure or is it better to satck perhaps 3x 1200s or 2x 1800s or ¿ what would you recommend ?

Thanks in advance for any comments.

_________________
Grüsse Rainer www.rsfotografia.com

Hallo ,

Heute Abend habe ich ein Spektrum von WR 134 fertig bekommen , mit 35 mue Spalt und einem Gitter mit 1800L/ mm. Immerhin ist das der schwaechste j e von mir spektroskpoierte Stern! Ich habe den halpha Bereich aufgenommen . Morgen werde ich das Spektrum zeigen........allerdings -wie nicht anders zu erwarten- ist auch nach 500sec Belichtungszeit das S/N sehr kümmerlich. Es ist nicht aussichtslos mit deutlich längerer Belichtungszeit vielleicht doch was Brauchbares zu erstellen, 8 min , wie heute Abend mal versucht, sind bei Weitem zu kurz mit dem C11....

Cheers Berthold

Hallo,

leider stand mir für diesen Versuch nur meine alte ST7 zur Verfügung....

....in der Anlage also das Spektrum vom 27.8.2012. Wie gesagt - recht kümmerlich! Mit sowas kann man nahezu nichts anfangen, schon klar. Es waren auch hohe Wolken da. Was ich aber eigentlich wissen wollte war, ob das überhaupt gehen könnte, einmal so einen schwachen Stern zu spektroskopieren , vor Allem aber auch, den aufzufinden und zu identifizieren.....vielleicht kommt was dabei raus , wenn man die Belichtungszeit verzehnfacht.......


berthold

Lieber Berthold:

Du hast wahrscheinlich recht: mit einer Belichtungszeit von etwa einer Uhr (in Stuecken, d.h. etwa 3-5 Einzelbeobachtungen nachher kombiniert) kommt etwas vernuenftiges heraus. Denn, ich weiss, dass mit einem grossen Teleskop von. c. 2,5m Durchmesser kann man ein Spektrum mit 1A Aufloesung und S/N ~ 200 eines Sterns mit V = 8 mag in c. einer Minute aufnehmen. Extrapoliert auf ein Teleskop von 11? (28 cm) bekommt man dasselbe (etwa) mit (150/28)^2 = c. 30 Minuten. Ob das 30 oder 60 Minuten muss man sehen. Von Deinem Spektrum kann ich das schlecht beurteilen. Ich brauche mehr Information, z.B. Ausser Gesamtbelichtungszeit, S/N (oder einfach No. van Elektronen), Aufloesung (oder einfach A par Pixel).
Kannst Du mir diese geben?

Danke und herzliche Gruesse!

Tony

From: Berthold Stober (fg-spek-convento@vds-astro.de)
Sent: Tuesday, August 28, 2012 6:34 AM
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Subject: [fg-spek] Re: A humble try of WR 134




Hallo,

leider stand mir für diesen Versuch nur meine alte ST7 zur Verfügung....

....in der Anlage also das Spektrum vom 27.8.2012. Wie gesagt - recht kümmerlich! Mit sowas kann man nahezu nichts anfangen, schon klar. Es waren auch hohe Wolken da. Was ich aber eigentlich wissen wollte war, ob das überhaupt gehen könnte, einmal so einen schwachen Stern zu spektroskopieren , vor Allem aber auch, den aufzufinden und zu identifizieren.....vielleicht kommt was dabei raus , wenn man die Belichtungszeit verzehnfacht.......


berthold

_________________
Tony Moffat

Hallo Berthold,

das ist wirklich eine Harte Nuss!
Ich hab 60 min belichtet und komme gerade mal auf ein S/N von 83 bei 5860-5868
Weit, weit weg von den geforderten 200!

Viele Grüße
Siegfried

naja, das ist aber doch BEDEUTEND besser, als was ich da abgeliefert habe, immerhin erkennt man ja wenigstens die NAtriumlinien, womit eine ungefähre Kallibrierung schon mal möglich ist.......bei mir sieht ma ja schlicht weg so gut wie nichts, als dass das höchst wahrscheinlich der richtige Stern ist.....)

berthold

ach, ich habe noch was vergessen zu sagen:

Du hast 3x3 gebinnt? Stimmt das? Dann kriegts Du natürlich zunächst mal hellere Spektren, aber verlierst an R. Wie hoch ist das hier? Ich denke mal das asymmertisches Binning was bringen könnte, weiß das aber nicht ganz sicher......in welchem Wellenlängenbreich sollte denn der Stern in erster Linie untersucht werden, wenn überhaupt? Und........was ist eigentlich genau die Fragestellung, noch nicht mal das konnte ich Otmar erklären.....

cheers berthold

Hallo Berthold,

mit 3x3bin erreiche ich noch ein R von 8000, das sollte reichen.
Um sicherzustellen, ob der richtige Stern am Spalt ist, habe ich den SA100 vor die Guidingkamera montiert. Da sieht man sofort ob das Objekt passt! Ob HeII 5411 oder HeI 5876 untersucht wird weiß ich auch nicht.

Viele Grüße
Siegfried

Schade dass ich wegen meiner Umzugsaktivitäten nichts beitragen kann.
--
Diese Nachricht wurde von meinem Android Mobiltelefon mit GMX Mail gesendet.



Hold Siegfried <fg-spek-convento@vds-astro.de> schrieb:

_________________
Herzliche Grüße / best regards

Lothar

https://lotharschanne.wordpress.com/

Hallo Siegfried,

Was ist ein SA100?

Berthold

Hallo Siegfried,

Was ist ein SA100?

Berthold

Hallo Berthold!

Der SA 100

http://www.teleskop-express.de/shop/pro ... kopie.html

ist ein durchaus brauchbares Klein-Spektroskop mit niedriger Auflösung.
Die Ergebnisse, die gerade an schwachen Objekten damit erzielt werden können, sind absolut bemerkenswert. Am 3C273 wäre er möglicherweise einer LISA sogar etwas überlegen.

Herzliche Grüße

Gerhard

Danke Gerhard für den Hinweis, raffiniert und sehr schlau........aber......

vorstellen kann ich mir das aber dennoch nicht richtig......mit der Guiding kamera muß ich doch auf einen Stern punktgenau nachführen.....sonst muss ich ja die guiding camera von derm guidingrohr abnehmen, den STA draufschrauben, gucken, dann den STA abschrauben, die Guiding camera wieder an das Fernrohr dran machen ohne das Gitter......dann muss ich die Montierung wieder neu kallibrieren.........scheint mir äußerst umständlich......wahrscheinlich wird von Euch das ganz anders gemacht...aber wie ?

Vielleicht möchte jemand von Euch dazu mal ein paar Bilder zeigen?


cheers Berthold

Hallo,
ich finde, den Staranalyzer vor die Guidingkamera zu setzen, eine hervorragende Idee. Da man sowohl das Spektrum 0-ter als auch 1-ter Ordnung sieht (bei hellen Sternen auch 2-ter Ordnung), kann man den SA dauerhaft dranlassen. Das Spektrum 0-ter Ordnung, d.h. das normale Bild des Sterns, kann man ohne weiteres zum Guiden nehmen. Das Spektrum 1-ter Ordnung liegt etwas abseits, so daß es keine störende Auswirkung hat. Man muß allerdings naturgemäß mit einem Lichtverlust rechnen, da natürlich Licht für die Spektren höherer als 0-ter Ordnung abgezweigt wird. Mich würde interessieren, um wieviel mag man dadurch eingeschränkt wird.
Viele Grüße
Christian

Gruesst Euch!

Ich haette gern die Pixel-Breite in A gewuesst, auf die die Rechnung vom Signal-Rausch Verhaeltnisse gebildet wurden.

Danke!

Tony

_________________
Tony Moffat

Hi together! First, I really appreciate your lasting effort and preparation for the campaign in 2013. Thanks a lot for that! In the background I am still active and try to obtain telescope time at Teide. However, that is still difficult and success is not granted, yet. It depends on various issues. Tony and me are working on it. IAC80 has an SBIG spectrograph now with R about 2000. This is not the stuff we need and I told that to the IAC people. I try to convince them to buy a Shelyak Echelle for the telescope. They do it only if at least one local research group is interested to work with is. Such open questions are answered in the campaign webpage. Check it out at “The project“, Bertold.

Go ahead!

Cheers, Thomas

Hello all,

A clever idea The light in the zero order of the Star Analyser is ~20% so the zero order is ~2 magnitudes fainter

Cheers
Robin

Hello,

WR 134 has 8 m, 2 fainter is 10 m..... so I think it is not suitible as guiding star with a ALCCD5....

Perhabs I could provide my Shelyak echelle for the studies in teneriffa......
So it could be easier to get telescope time in teneriffa....(?)...but we need a seeing diameter of the starlight from ca 50 mue and a focal ratio of the telescope from 1:6 or so . I don't know the parameters of the telescope IAC 80.....What do you think about this , Thomas?

Berthold

Hi Berthold! Is that an offer for the whole campaign of four months? That would be VERY generous, indeed. I would forward it to IAC. The f/11.3 IAC80 has a focal length of 9m, hence, a 1 arcsec seeing disk of about 40 micron (28 micron for a typical 0.7 arcsec seeing disk).

If we use a focal reducer as for Mons, we could get, say, f/7 and a 1 arcsec disk of about 27 micron (19 micron for a typical 0.7 arcsec seeing disk). That would work, as I already told the IAC guys. The stellar image would completely fall into the fiber. I am not familiar with the EShel guiding procedure, though.

I would tell them that we install a prototype configuration as at Mons so that they can make up their mind if they want to get rid of their SBIG stuff and later buy an own EShel. I would ask Shelyak anyway if they are interested to lend an EShel for PR reasons. But that is not granted, of course.

Can I forward your offer to IAC?

Thomas

Hello Thomas,

Of course, that must be for the hole compaign.....and I mean it for the hole compaign.....

I think we must be sure that the beam cone from the telescope is about 1:7 or so and we must have a seeing disk of about 50 mue because the pinhole in the fiberinjection is 50 mue so wie need effectivly (?) a seeing disk of 60 mue perhaps because we need some light for the guiding camera. Further wie need that tHe IAC 80 mount is compatible with the ST4 standard from SBIG....or we need a guiding camera from IAC. In this case we need a connection from the guiding camera of IAC to my fiberinjection .

This is important to be checked before we speak about more details.....further points for me are:

I have not yet the calibration unit from Shelyak .......could I take mo with me, if I would be necessary in teneriffa........?

you can forward it so far in IAC

Cheers
Berthold

Hi Guys,

due to the nearly Gaussian intensity distribution of the seeing disk you will only get 50 % through a pin hole with the same diameter.

_________________
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/

Hi Daniel! No, it's more. The light flux is always represented by the integral function but not by FWHM. The question is, if we can guide a 20 micron FWHM stellar image on a 50 micron fiber. Berthold told me that he uses the reflected light on the fiber. But presumably we can use other techniques if we get telescope time at all.

Cheers, Thomas

Hi together! A short remark on the language. This ConVento discussion section is dedicated to international ProAm campaigns. Please understand that english messages are essential so that they are not considered as spam.

Cheers, Thomas

Hi Thomas,

it is approx. 50 %. I used the numerical integration of a 2-dim Gaussian. See the SpecEff Excel sheet for reference.

I could lend two fiberinjections:
One with a 50 um core fiber which is polished under a small angle. Fiber length is about 5 m. (Spektrum 42)


And one that can be used with any standard SMA fiber:
http://spektroskopieforum.vdsastro.de/v ... php?t=3851

_________________
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/

Hello all.

The standard guiding would probably work ok. (If the star is lost the guiding will stop until it reappears at the edge of the hole when it will pick it up again) but this is not good though as the star will move around in the hole and if it spends more time on one side the wavelength calibration will shift. This is a magnitude 8 star in a 0.8m scope though so it will be very bright. We should not need much of the light to guide on.

If there is a problem, I can see two solutions.

1. Defocus slightly until the star image overlaps the hole slightly (almost all the starlight still goes down the fibre)
or
2. Run at f11. It needs to be checked but I suspect it will not be a problem for the eShel provided enough of the grating is illuminated to give the required resolution.

Cheers
Robin


----- Original Message -----
From: Thomas Eversberg (fg-spek-convento@vds-astro.de)
To: fg-spek-convento@vds-astro.de (fg-spek-convento@vds-astro.de)
Sent: Monday, September 03, 2012 1:39 PM
Subject: [fg-spek] Re: A humble try of WR 134



Hi Daniel!
Zitat: due to the nearly Gaussian intensity distribution of the seeing disk you will only get 50 % through a pin hole with the same diameter.

No, it's more. The light flux is always represented by the integral function but not by FWHM. The question is, if we can guide a 20 micron FWHM stellar image on a 50 micron fiber. Berthold told me that he uses the reflected light on the fiber. But presumably we can use other techniques if we get telescope time at all.

Cheers, Thomas

Hallo Daniel,
die Energieverteilung für eine feste Wellenlänge wird nicht durch eine Gaussverteilung beschrieben, sondern durch

I(theta)=I(0)(2*J1(k*a*sin theta)/(k*a*sin theta))^2

mit theta Winkel zur optischen Achse, k= 2*pi / lamda und J1 = Besselfunktion 1. Ordnung.
Unter Berücksichtigung der rekursiven Eigenschaften kann das entsprechende Integral ohne großen Aufwand exakt gelöst werden. Details s. Born, Wolf, Principles of Optics, Kap. 8.5.2 The circular aperture.

Man erhält letztendlich mit w als Radius des kreises, für dessen Inneres die Energie berechnet wird,

L(w)=1-J0(k*a*w)^2-J1(k*a*w)^2

Wenn man nun noch über lambda integrieren will, so geht das vermutlich nur numerisch. Ich habe in einer sehr umfangreichen Integraltafel nachgeschaut und dort nichts gefunden. Wahrscheinlich reicht auch die Verwendung einer mittleren Wellenlänge.
Die Approximation durch eine Gaussfunktion ist unzulässig, da die Gaussfunktion im Gegensatz zu den Besselfunktion keine Nullstelle hat, d.h. der Lichtanteil, der in die Faser geht wird unterschätzt. Falls Interesse besteht kann ich aber auch gerne die Zahlen liefern.
Viele Grüße
Christian

Hello all.

The standard guiding will probably work ok. (If the star is lost the guiding will stop until the star reappears at the edge of the hole in the mirror when it will pick it up again). This is not good if it is a slit as the star will move around in the slit and if it spends more time on one side the wavelength calibration will shift but I do not think it is a problem with a fibre. Any way. this is a magnitude 8 star in a 0.8m scope so it will be very bright. We should not need much of the light to guide on so there might still be enough spillage. There are plenty of sEhel users with 280mm scopes for example who guide ok

Even if there is a problem, I can see two simple solutions.

1. Defocus slightly until the star image overlaps the hole slightly (almost all the starlight still goes down the fibre)
or
2. Run at f11 which will give a star imsge big enough to fill the hole. It needs to be checked but I suspect it will not be a problem for the eShel provided enough of the grating is illuminated to give the required resolution.

Cheers
Robin

Hi!

Again! This ConVento discussion section is dedicated to international ProAm campaigns. Please understand that english messages are essential so that they are not considered as spam.

Und in deutsch: Diese ConVento Diskussion widmet sich internationelen ProAm-Kampagnen. Bitte versteht, dass englsiche Nachrichten essentiell sind so dass sie nicht als Spam-Mail bei den Mailinglisten angesehen werden. Schreibt bitte in englisch, ansonsten sind die professionellen Listennutzer sauer. Ich habe entsprechende Mails erhalten.

Cheers, Thomas

No, Daniel, either Gauss or a similar function, imagine a very strongly peaked and sharp function due to perfect seeing. Then you can imagine that the wings outside FWHM will deliver much less light than the core. The situation becomes worse with bad seeing.

I agree with you, Robin. I am not sure why Bertold needs f/7. Is that a general requiremend for the EShel due to potential FRD or only for his telescope to reduce the seeing disk diameter?

But for now Berthold's offer is most important and I already transferred it to IAC. Waiting for their answer.

Thomas

This looks a lot like the diffraction due to a round hole. But I think we were actually talking about seeing profiles, which are close to gaussian, although a Moffat (http://adsabs.harvard.edu/abs/1969A%26A.....3..455M ) profile fits better, with stronger wings than a gaussian. In fact, by varying one of the Moffat profiles (beta), you can get profiles between a gaussian (beta--> infinity) and a (forgotten the naqme now, but it goes as 1/(1+(r/R)^2) ) (beta = 2), with many pofiles in between and even worse than the latter. In this old paper I also integrate the diffraction over a hole ...

Tony

_________________
Tony Moffat

Hi Thomas

I measured the seeing disk of a star with my 10" SC and it is realy nearly a gaussian, but I also know the guiding problem and what you mean, Thomas. I always was able to guide a start with FWHM = seeing disk/2. This has to be checked at the telescope you want to use the fiber.

_________________
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/

OK, Daniel! But FWHM = seeing disk/2 is not correct. The seeing disk is FWHM by definition and Teide delivers a seeing disk of about 30 microns. If we use a 50 micron fiber, the star might completely fall into its aperture. In Chile I once guided by eye for about 5 weeks under the same circumstances (and I was alone). Hard work but ok. However, I am confident that we will manage this (minor) problem as soon as we get telescope time (see Robin's remarks).

Cherio, Thomas

Yes Thomas, I meant seeing disk * 2 = fibre core and then you get about 90 % on the surface of the fibre.

Hi Christian,

this is the diffraction pattern of a point source. Only optical systems which work at diffraction limit will image this pattern. Telescopes with technologies like adaptive optics and space telescops (or small telescops).

_________________
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/

Hi Daniel,
the diffraction theory is valid for any optical system with an aperture even for extended light sources. Stars can be taken for point sources. Therefore we can apply the Kirchhoff formula. But stray light is not considered in this theory. This may cause some deviation of the mesured values from the theory.
Cheers
Christian

OK I forgot about FRD but the exit FR cannot be lower at f11 than at f7 can it? In fact in our case it will help as it will make sure the grating is more illuminated.

Any way if we want to, we can always run at f7 and defocuss the telescope slightly. 0.7 arcsec seeing is a nice "problem" to have

Berthold's offer is indeed very good. I am sure the eShel will be a perfect excellent instrument for this application

Cheers
Robin

Hi Christian

The seeing disk is in most cases much bigger as the diffraction pattern. The diffraction pattern jumps around in an area defined by the seeing disk (thats one of the effects called seeing). This is why the diffractin pattern is smeared out to a nearly gaussian intensity distribution.
If the exposure time is lower than the typical seeing (< 50 ms) than you may could se the diffraction pattern (Kolmogorov theory of seeing).

_________________
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/

I am on WR134 now. (280mm aperture f11 LHIRES 1200l/mm grating) There is a mag 8 star TYC2683-02150-1 just 1 arcmin away from WR134 clearly visible in the LHIRES guider field. This might also be visible in the eShel field at 0.8m/f7. If so this could be used for guiding.



Robin

Similarly there is a mag 10 star 1 arcmin from WR135 TYC2683-02538-1 which could be used provided the guider field is more than 2 arcmin in diameter.

Robin

Hello Robin

good idea! I guided on WR134on the slit. So the star is even more fainter i should take one of the discribed stars as you said....

What do you mean? The fiber has about 1:4 or 1:5. The IAC 80 has 1:9 . The seeing disk at IAC 80 is about 40 or so. Is it a problem in your eyes if the diameter of the fiber is 50 mue?

Cheers Berthold

Hello Berthold,
I do not think there is a problem if the star image is smaller than the fibre diameter but perhaps we should ask an expert on fibre fed spectrographs to be sure.

I have measured WR134 and WR135 tonight, 1 hour total exposure on each. The resolution with 1200 grating and 35um slit is 1.3A They look quite good but I will process them and measure the SNR tomorrow.

Cheers
Robin

Hi Robin:

That's awfully close for an equally bright companion. WR134 itself is also 8th mag. Are you sure you mean 1" away and not 1'? If it`s actually 1" then the two stars will always have to be observed together with most instruments.

Cheers, Tony

_________________
Tony Moffat

Hello Robin,

I tried WR 134 yesterday too, but it was only late in the night when skies become clear......and I have rather problems with my CCD 1603, so my results are not good enough to be demonstrated here........

cheers
berthold

Hi together! I do not declare myself an expert in fiber fed spectrographs. But I see no reason to expect trouble if the stellar image is smaller then the fiber aperture - in fact, it should be better, especially if potential guiding problems do not occur. I experienced this during my observations on gamma Velorum. Either we guide on the neighbored star or as Robin described further above.

Another open question to me is FRD. Do we need f/6 or f/7 to reduce FRD or does Berthold use this focal ratio because he needs to with his telescope?

For IAC80 I presume this to be solvable. If we get the telescope on Teide I will ask Shelyak for more details.

Thomas

Hello Thomas,

the eShel in constructed for telescopes with focal ratio 6,3. The FRD makes perhabs 1:4 on the other end of the fiber. So , and I think, ONLY so , the eShel will be full illuminated....so....when I use a telescope with 1:9 , perhabs I get by FRD on the other end of the fiber only 1:7 or so........and now, the eShel will be not fully illuminated.......

I am not sure if me comment is ok......but I think so....

But all those discussions will make no sense, if we don't know, if we will get time for the IAC80.......

cheers berthold

Hello,

now here is my first spectrum of WR134, which seems to me somewhat useful ......but I don't know it........

For the first time, I reduced it with vspec.......the program crashed down perhaps 8 times...also I tried 8 times!!....but I have to repeat the sms context procedure, because it is a long time ago when I used midas context SMS the last one. Therefore I cannot say anything about S/N or so.......

The night was slightly clouded and there are 5 frames with 540 sec. I cannot say more for the first..........

cheers berthold

PS :I saw the answer from IAC! So we cannot use our guiding ALCCD5.......therefore they must say us, how we can connect my fiberinjection with the guiding system of the IAC80, they have ....but first of all , they must say us, if they allow us to use the IAC80. Befor we have no positive answer , we must not think about those details........

I recall that the team that went to IAC80 for the delta Sco campaign in July 2011 (delSco blog (check days #1 and #2)) had difficulties with guider focus on the Lhires. Eventually, they overcame the problem, but I am lacking on details for how that was solved. However, keep in mind that this could have been caused/influenced by the way they fed the calibration light into the spectrograph. They appear to have used a prism somewhere to feed the light in, instead of hanging a Filly bulb in front of the 80cm telescope. I suppose the Filly lamp will be too dim for the big scope.
I suppose this experience alerts us that there might be more than just "autoguiding", to putting a Lhires on a scope that may be not accessible for manually turning the Neon lamp on...

_________________
Fil.

Now, that is the result from 120909


cheers berthold

infortunalely I can't load up the 2D spectra of the star and the calibration spectrum....

Hello Bethold
I tried recalibrating your spectrum using the Na D lines and put it on top of my spectrum to compare them (attached)

There is a large difference in the strength of the emission lines. (your spectrum is much flatter) Did you subtract the dark and background?

Cheers
Robin