spectro-aras.com

To: James,

Sorry for not responding. I had to send my eShel injector box back to Shelyak for fine-tuning.
Please remember to set you Canon 135 F/2 to F/2 on a Canon SLR camera body before you set-up, or
you will be getting much weaker snr on your spectra. Another item is selecting which side of the
science fiber is the "efficient" side, as Christian mentions you get btw 10-20% more signal by
picking the correct "side" of the fiber; I had Shelyak do this for me when they were fixing the injector box.

James

Hi James,

Thanks for the info - I indeed do have the new lens set to F/2.

Also, when you refer to the "efficient side" do you mean which end of the fiber is inserted in the injection unit vs which is inserted into the collimator?

James

I'm almost on my 2nd year with the eShel without a processed spectrum. I had the injector checked by Shelyak and started to take and process new spectra,
but I think my PRISM software is making it difficult for ISIS V6.11 to process.
I noticed that PRISM, by default, saves the .fits image to Int (16-bit signed). But when cursor-ring over the raw and CMED 3x3 binned images, the Y-axis starts at 0 on the bottom of the frame and maximum value on the top for my images. Is this correct? When I need to place my Y-midpoint value for the order #34,
will Isis correctly know which way the y-axis flows? If not, Isis will not find the blaze function of my eShel spectral images. Here is a screen shot of
my situation (thor_Capella):


If anyone want to check-out my "raw" .FITS (before CMED) here it is for download:
http://astroimage.info/files/thor_Capella.fits

I hope I have derived the correct position value of x for the 6583.906A on the CMED and the correct value of Y-midpoint, but I'm not sure Isis "likes"
the inverted y-axis.

James

Hello James,

If I were you, first I would review the PRISM setup and try to do the practice to solve these questions, wouldn't you ? Then review the ISIS indications, that is all that I can say to you.

But in your THOR_CAPELLA image I noted there is an inclination camera default, at first time, you needed to correct it, you can see the first picture, do you remember it ?

I connect THOR_CAPELLA's name with the fact that you have observed this star with the current -wrong- camera position. In my opinion it's not necessary to wait for the night and observe a star to put the CCD in its correct way. 

You could take advantage of the THOR light and you can use these same files in two ways, that is, how aTHOR_**.fits control light and image to reduce at the same time, you'll obtain a graphic similar to the second image.
I hope that you can resolve these little problems soon, and could show us the first results with your impressive equipment.

On the other hand, I don't know if I've answered your questions and/or if that will be useful for you.

Regards, Joan.

To: Joan,

Thanks for the quick response! I'm using Isis V6.1.1 and PRSIM 10.4.20.930.
Your image here looks very useful. My alignment shows that I was off by 0.3 degrees on order #34, but I was using figure 22 from this link:
http://www.astrosurf.com/buil/isis/eshel/tuto1.htm
and not your much easier to align figure using the identical "end" of same Thor feature of the reversed image-order on the right-hand of the enclosed frame.

I'm working off the tutorial Christian made for Isis 3 (very old) so I'm kind of imagining how that translates to the new camera(Zwo ASI6200MM), with a new version of the eShel (after 2018), with new LINES, DEF_ORDER, DEF_LAMBDA, and DEF_YPOS .LST text files that are necessary when the enhancements for the new eShel 2 came about; see:
http://www.astrosurf.com/buil/asi6200mm/

I'm not very good as balancing the technical jargon, and my Google "French" at translation is probably bad, but I want to try and get past Check2,
which has been a barrier im my eShel processing so far......I'll use your rotation figure now and see if I get to the end of processing with correct blaze.

Sincerely
James

To: Joan,

I took the eShel out of the "wine-cooler" and rotated the ASI6200MM until I got the rotations you indicated.
Rotation btw the two points in the upper order (according to PRISM Dist/Rot tool) was 360 and on the lower's two point (Order #36),
I got 359.9 degrees after tightening the 3 screws on the eShel/camera base with the eShel back in the cooler.

Here is an image of the "new" Thor (2x2) bin measured in PRISM and imported and labeled in PS:


I'll retake my data and see if processing gets further in the eShel pipeline. Since Vega is gone I'm using the
AOV star HD031295 for my instrument response.

Thanks against for taking the time and helping me with this complex spectoscope!

James

Hi James,

Fine, but you know that it's only a first approximation. Really I don't understand very well
- lack of idiomatic comprehension English/Catalan, in my case -, which is the matter of your problem,
so I will start at the beginning.

I understand you take the integrations with PRISM and save them in binning 1x1, that is perfect.


At the moment, if I were you I would forget to use the sky objects to make in station yours eShel2 and ASI6200MM.
short series of  five THOR_*, TUNG_* images every time, of course, you have taken previously only a serie
of darks with the same temperature sensor camera, you also know that the BIAS is a binning 1x1
600 level synthetic image in this way.

Obviously, there's the last ISIS version in your computer, and you in "Masters" window have computed a
binning 1x1 dark image. Then in "Instruments" CMOS key, you tread these 5 THOR_*, TUNG_* images, with
the Median filter 3x3, Binning 2x2 and Strength = 2.

After that in the "Masters" window, in "Compute a mean image", you take in the THOR_*, TUNG_* masters.

Then in "Instruments" eShek key put the TUNG_** and THOR_** masters in its place and use the THOR_** serie
for a image in "generic name" "Number" and "Object name", active also and only "Function de laze liseé".

Enter in the "Setup" window and fill up your eShel and camera characteristics and active all in "Processing control".

The aim is only the CHECK2 control image now, not any graphic, as you can see in this picture. So first the most
important thing is have been centred the 3rt reference point, turning right/left the camera, you can ajuste the 1 and 2 points
changing the setup parameters. You need to repite this operation sometimes, of  course you can obtain the THOR graphicsif you want.
I hope that all I said here will be understood and useful for you, if not tell me it.

Regards, Joan.

To: Joan,

Thank you.....I'm ok with all the standard procedures in IsV6.1.1 until your paragraph "The aim is only the CHECK2...."
I sent a private email to Christian, but understand he's a very busy person, to get more recent copies of the .LST eShel geometry
files (LINES, DEF_ORDER, DEF_LAMBDA, and DEF_YPOS .LST text files) we need for using for eShel2, Canon 135mm F2 lens, and ZWO ASI6200MM Pro.
Thanks for the "stingray" diagram, looks very helpful.

By the way, what do you do if the Cmos camera is not properly centered in the at Order #54? My issues is if I get any 2 of the 3 "squares"
aligned, I can't get the 3rd squared with the Thor emission line. I tried to tilt the cmos on the eShel, but it seemed to make the
geometry worse to interpret, so I'm just dealing with rotation/focus for now. Will let you know if I get further along than Check2!

Sincerely Yours,

James

Hi James,

In my opinion, your file "lines.lst" is still useful now, but I don't know if exists a new version, because I'm using the RELCO version for it, the "def_order.lst" it's a file that you need to make yourself,  it depends of you camera characteristics and if you want to work with a windows withthe intention of save your HD out  unnecessary space files, referent the "def_lambda.lst" it is a file that ISIS generate automatically, finally I think you don't need to "def_ypos.lst" file if you have activate "Automatic orders detection" in the "eShel Setup" window. Of course, you need to fill up this last one with all its parameters. 

You need to have well defined all these ones if not all that you make would be an esteril job. 

I don't have any answer for your second paragraph, sorry,  and don't understand it very well, I think that it's better you can send a picture about.

Remember the first thing is to make in place the point number 3.

Cheers, Joan.

To: Joan,

Yes I'm going about defining LINES, DEF_LAMBDA, & DEF_ORDER .txt files. II got 50 out of 60 orders (zones matching thor) identified and
am adjusting the parameters to get more....will keep you posted and thanks for your great assistance!

James