I started a new post because the current TG posts in the Forum are getting pretty lengthy and actually getting more involved than I am presently.
I am feeling a little stupid right about now because I cannot seem to get off the ground with the basics of TG. I have read the many posts in the forum, and it is obvious many have gotten the hang of using TG. But I am seriously missing the basics which I do not see here (perhaps I have simply missed seeing them).
A number of years ago, Tim Crawford and I developed a spreadsheet that used either M67 or Landolt fields to obtain TCs (remember that, Tim?). We used the SIPT feature in AIP4WIN, which meant we had to click on each star in each image to obtain instrumental mags. We then copied and pasted the log into our spreadsheet. We did this for up to 4 images, and our spread sheet put out the TCs complete with graphs.
With TG, it appears we can use the MMT feature in AIP to obtain our TCs. I would like to use M67 as the field, but nowhere in the forum, in VSP, or in the TG User Guide can I find the M67 data required for each star in M67. I did try downloading a chart and photometry table for M67 based on the coordinates. I succeeded in getting comp stars, but the field star IDs and mag info were not there.
I did try the demo file provided with TG just to see how it worked. That file does show IDs 1-20. So I am assuming that once I have all of those stars along with their BIRV filter data, I can proceed with the AIP processing. But I think I would first need to put all of that data into the AIP DB. I have done that successfully many times with Photomcap (a truly fabulous program). For the heck of it, I tried entering the photometry table from the chart I created even though they were only comps, not the field stars. But when I hit “Do It”, I get the error message that the file did not finish properly (no stars were plotted). The chart number is 14529CD and the Photomcap version is 14. I tried it using Ver 15 and 16 as well with no luck. Another chart number 14528FIQ also resulted in this message.
So after all of this I just know I am missing something very elementary, but I am stumped. So I have 3 questions:
- How do I find the necessary info to put into AIP4WIN to get TG up and running?
- Can I use Photomcap to enter this info into AIP, or do I need to do it all manually?
- Using AIP4WIN MMT and assuming I have 3 or 4 sets of images (each set containing images for each filter) can I click on the field stars in 1 image and AIP will return the data for all filters in all images?
BTW-if there is a link describing all of this, I would be very happy with that rather than having someone explain this all to me.
Hopefully George, Gordon and I can keep track of this post thread too? Not a problem and if it helps that's good. I suspect Gordon will try to address the specific TG/AIP4Win questions but if I understand your question about standard comps, I would point you to the last question on the VSP request page - "WOULD YOU LIKE A STANDARD FIELD CHART?"
Check this and you will get a photometry table and/or chart with all the standard comps (with label, auid and mags) that Arne recently generated. BTW, it may be easier to use the name ev cnc rather than remembering the RA/Dec?
Let's stop here and see if that answers your first need?
pardon the bolding, in chrome I don't see some of the font boxes to correct it ;-(
Thanks for the
Thanks for the reply.
I did originally try all of your suggestions with no success. So after your reply I tried it again. This time it worked just fine. I THINK my error was asking for EN Cnc, not EV Cnc. This time I got the table and everything needed. And I was able to use Photomcap to get the data into AIP. So that part is now all good.
I do still have a question or two about AIP. I did try creating my own file in AIP and I did a run using the Instrumental Mag, 1 star/line option. Apparently I did it almost correctly because the log came in the format out just like the file. But there are 2 items that are different.
First, I notice that the first item in the TG M67 file is M67 itself complete with all the info. My first item is EV Cnc. This was the Variable that is the first star I select in AIP. This, of course, is meaningless since we want only the stars C1, C2, C3, etc. So how did you get M67 as the first item in the TG file. Was this just any star that was used as a “dummy” to get to the C stars that are the actual targets?
Second, the IDs in my log are the AUID numbers. The IDs in the TG file are 1,2,3,etc.It would be easier for me to use 1,2,3, because I will number those stars accordingly on my chart in the order I click on them. So how do I get the labels to read 1,2,3, etc.
Our posts overlapped. Let me know if what I posted answers your questions. In net, yes, the M67 was just a dummy to get the comp star numbers to match Boulder ids. And, the file I posted will let you generate labels 1,2,3 etc.
This is wonderful, Gordon. Thanks so much. I am printing out your latest post and have dowloaded the latest TG verrion along with the guide. I also have the txt file you attached. Now I can get down to business and work throuogh it all.
Again, thanks so much for your hep.
You don't need all the magnitude information on the M67 stars. TG automatically retrieves it from the AAVSO web site's VSP tool.
What you do need is a comp list with the 64 ids (1-64) so you can select those stars in AIP4WIN and get the right Boulder identifier. (The TG Users guide V 5.6 has a new appendix A that shows an image of the M67 field with the 1-64 star ids).
To help get the right comp star ids I created an AIP4WIN "STAR" file that contains all 64 M67 standard stars. It is attached to this post. (NOTE: When you download it, remove the _.txt at the end of the file name. I had to add _.txt to be able to post the file on this blog. AIP4WIN is looking for the file to end in .STAR".) Copy this M67_Henden_Field_Comps.STAR file into the AIP4WIN/Data directory (usually C:\Program Files (x86)\AIP4Win\Data).
Now start MMT. On the MMT Images tab load all your M67 images for all the filters. Select one image to locate the comps (I ususally select one of the V filter images). Go to the MMT Stars tab and click "Recall..." to load that M67 file containig all the comps.
Select any star as the M67 target (i.e. AIP4WIN's "V" star - which again, is not used). Now select the comp stars - you'll see the comp number matches the boulder id. Once all the comps are selected, go to the AIP4WIN Report tab and select the options shown in the TG Users Guide section 22.214.171.124. Then go to the AIP4WIN Execute tab, pick a good guide star and "Run Photometry". Because you have different filter images, AIP4WIN will usually ask you reconfirm the guide star between images.
AIP4WIN will find all the stars in each image. Sometimes stars in one band won't have adequate SNR for AIP4WIN, but that's OK. AIP4WIN indicates the error in the output report file and TG handles it.
The AIP Instrument Magnitudes file created this wasy can be directly loaded into TG.
FYI, TG goes to the AAVSO web site to retrieve the current standard star magnitudes from VSP, so don't worry about the magnitudes in the STAR file.
One other suggestion - if you want to ease the star selection burden and only identify the first 30 standard stars, edit the STAR file (in Notepad) by deleting all stars above 30.) Pragmatically I find the results are very good.
Another point - when you run TG you will get an error message that some of the Boulder id do not have an AUID counterpart. That's true - some of the original stars are no longer in the standards field. Don't worry, TG will generate the transforms based on the other stars.
Again, think about using VPHOT to identify the stars - it saves a lot of work
All I can say is
All I can say is WOW! TG sure does rock! Very nice job. I have worked my way through generating the TCs and now need to figure out how to apply those TCs to AIP4WIN derived mags. It appears all I need to do is first enter those TCs into TransformApplier. I then copy the data log from AIP4WIN, press the Process button, and voila, the transformed data is kicked out and ready to submit. Sound correct?
May I please make a suggestion? I printed out your excellent message to me that showed how to access the Henden data and apply it to TG. I added this to my printout of the TG User’s Guide. I did not see this information in the TG User’s Guide (or I simply missed it if it is there) and that was why I needed help getting jump started. I think it would be a good idea if this information as included at the beginning of the Guide as without it, TG cannot, of course, be used.
BTW-I did delete the last 30 stars from the Henden text at your suggestion, but I did things the hard way by selecting the 30 stars in AIP. I have not used VPHOT because I have always used AIP for reduction and found it to be extremely easy to use. If VPHOT will be quicker and easier for the star selection process, I will simply learn how to use it.
Again, Many thanks for your help.
We - and other Python users - have found a problem with the terminal emulator on the latest Mac OS X V.10.10 release. TG will not run. Some conflict between Python and the new OS X. We'll let you know once we find a workaround.
Good to hear from you. I, similar to you, have always used another software for reduction (Maxim). I used VPHOT only sparingly, and cannot say I am knowledgeable about its use.
However, for TG, VPHOT rocks. It does all the work for you. You just load your stacked BVRI images to VPHOT. Select "Standard Stars from Catalog" and it places all the apertures, etc. Then just select the SNR, etc you want, and write the output, and you are done. I think I could do it all in less that 1 minute per color. Its worth the effort to learn VPHOT for transformations.
Thanks for your
Thanks for your input. Now tht I have TG under my belt, my plan is to attack VPHOT tomorrow. I dimly remember the application of TCs from the good old days of the BVRI star project which you headed up. So I still have a little work to do before actually applying the TCs to my observations. I still have the papers by Priscillla Benson as well as the one by Lou Cohen (of which you had a part in writing), so I have the ammo to stir up the old memory banks.
Now that the weather has broke, I am getting my 2 spectroscopic telescopes and my photometry scope back in business. It has been a long winter, but I think you East Coasters all about that.