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I have decided to try to learn to use MIDAS. I have managed to download the required software and can get it running on my Win 8 machine.

I planned to work through the examples in Thomas and Klaus's book Spectroscopic Instrumentation but I fell at the first problem.

How do I get my .FIT images in the Windows directories into the ones accessible by MIDAS in the VM/Fedora/MIDAS ?

I am sure this will be the first of many dumb questions.

Thanks Andrew

I managed to drag and drop a file to get started but I could do with a way to make files more generally available.

Form this I managed to display the image a plot some pixel values. However, I can't get the compute/image to work. I get the error

Midas 025> compute/image h3=HIP3885-1.fit
(ERR) SCFOPN: h3=HIP3885.bdf - FRMNAC
(OSY) MID_ACCFRM:
Frame not accessible: Check the name of the frame you use in the given context.
Midas 026>

I can display the image and under properties the file has read and write permissions. On the other hand extract/image seems to work.

Thanks for any advise you can give.

Regards Andrew

Hi Andrew,
you will find for MIDAS in the internet no real support. Have you thought about Iraf as an alternative? The support is much better and it is used by many professionals.
Regards Christian

I just assumed that MIDAS was the recommend route as it was on you web site! I will look into IRAF. Can you point me at a sight where I can download a packaged version? I assume I fill still have the files issue?

Thanks Andrew

I solved the compute/image problem by extract/image first taking all the image. Not sure if this is right but it worked.

Here are two sources for an easy installation
https://docs.astro.columbia.edu/attachm ... stallation
http://www.astronomy.ohio-state.edu/~kh ... stallation

You will find numereous tutorials in the internet, e. g.
http://iraf.noao.edu/tutorials/tutorials.html
http://www.twilightlandscapes.com/IRAFtutorial/
http://homepage.usask.ca/~ges125/Astron ... onIRAF.pdf

Regards Christian

Hi Andrew,

even without being supported MIDAS is still one of the two professional and still widely used tools. This is because it is tested and evaluated by thousands of professional users. The situation for IRAF is basically not different. From my point of view it is a matter of taste. I used both (MIDAS for my master and IRAF for my PhD) and have a slight preference for IRAF. This however might be because I was more familiar with data reduction after my master. We have only MIDAS on our website because Jürgen Neubert once took care for the respective installation. Nobody did this for IRAF, though.

Cheers, Thomas

Hi Thomas, the papers I read is surely not a representative selection. But I saw no paper written in the recent years where Midas was used. Compared two MIDAS Iraf is the more stable software. In MIDAS identifying the callibration lines can be very painful bacause this important routine dos'nt forgive even small input errors.
You will find a large variety of installation instructions for Iraf in the Internet that there is no need to offer it on our website. Because you can choose between a 32 bit and a 64 bit version we had to install a lot. But ther is really no need. There are sources which deliver a pakage which contains much more useful software.

http://ssb.stsci.edu/ureka/1.5.1/
http://astroconda.readthedocs.io/en/lat ... ation.html

Cheers
Christian

Thanks all IRAF it is then. I will learn how to install from the links you sent me so thanks for that.

You might want to update the software section of your website to reflect this current thinking.

I am sure I will be back with more questions on IRAF!

Regards Andrew

Hi Christian!
Doesn't matter if true. MIDAS works well, anyway.
No!
Can be, but when writing batch jobs, all this can be circumnavigated.
Almost everything you can find in our website can be found in the internet, as well. I presume that you appreciated the information donated from the group when you started with spectroscopy. I am surprised that you now consider certain information as not necessary in the section site.

No, that is only collecting some links and writing some explanationary texts to guide users through the procedure. If you want to convince users for professional tools you should help them at least as much as the amateur-Windows community does. Stating that a certain technique or tool is superior is not enough.
I suggest you collect such information, bring it into easy-to-understand order and send a respective sheet (best in html) to our admin. Then he can put it into our website as we did for Fedora/MIDAS.

Cheers, Thomas

Hi Andrew! It is also YOUR website!
I think only Christian uses IRAF, unfortunately. We would appreciate if you can write down your experience for the above mentioned "easy-to-understand guide" so that others benefit from it.

Cheers, Thomas

My experience so far is not so good.

I have VMware and installed ubuntu as an operating system on it following a youtube tutorial. I am not familiar with Linux but I do recall DOS so the command line is not too much of an issue.

However, just trying to change directory seems a challenge! If I do a dir I get a list of directories but when I then try to change to one with a cd it say there is no such directory. A steep learning curve which a kindle book is helping with.

On to IRAF I tried the 64-bit_step_by step but got error trying to access files on the site and other assorted error about missing files!

I then tried the ureka approach. I downloaded the file and put it in the home directory and typed sh install_ureka_1.5.1 only to get a can't open the file message.

My learning so far is that unless you are familiar with Linux/ubuntu to start with you need either to get familiar or have a much more integrated and robust package to install IRAF.

I will keep trying and report back.

Regards Andrew

Here is a comment from Gregor Rauw (Univ. Liège). Cheers, Thomas

Hello,

Maybe some clarifications and a translation of my statement concerning MIDAS vs. IRAF. I used MIDAS for my PhD because at that time this was the most efficient software to cope with data taken at ESO. However, in the meantime ESO has stopped supporting MIDAS, which means that there are no new releases and there are no new developments of tools for new instruments/applications. I still use MIDAS quite regularly (including also for my publications ), especially for long-slit spectroscopy where I have written my own suit of routines based on MIDAS commands. However, I found out meanwhile that for echelle spectroscopy, IRAF is MUCH superior to MIDAS. This is because the echelle routines of IRAF are much more userfriendly and versatile. Also, correcting telluric lines under IRAF is very easy and works a lot better than under MIDAS. There are other examples where IRAF is clearly superior. My bottom line is that both software have there pros and cons, but generally speaking IRAF is certainly the one that has the larger number of supporters in the professional astronomers community. Over recent years, the "reduce" packages developed by Piskunov & Valenti 2002 and running under IDL has also become quite popular, especially for echelle spectroscopy. Some of my colleagues also work under Python.

Cheers,

Gregor

Hello Gregor,
are you talking about Pyraf?
Christian

Hello Christian,

Personally, I'm not using Python myself. From what I know about Pyraf, this is mainly a Python interface to IRAF. But there are other Python packages, such as Astropy, though I do not know about the performances of these tools.

Cheers,

Gregor

File names must not contain minus or plus sign. Midas tries to subtract 1.fit from HIP3885.bdf
h3 = HIP3885.bdf - 1.fit

Better use undescore in file names HIP3885_1.fit

guenter

_________________
Im längsten Frieden spricht der Mensch nicht so viel Unsinn und Unwahrheit als im kürzesten Kriege. (Jean Paul)

Thanks good advice. I have moved to using IRAF now but the same point is valid.

Regards Andrew.