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Companion star not in field

EIU
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I am taking images of BL Boo and stacking 6 one minute images for each data point. When I make my sequence, everything is fine, but when I run the report it shows graphs for the variable star and check star but says it can not find the companion star in any of the images. I have tried this with three different companion stars now. Is this a v-photo glitch or have I done something wrong? I would attach one of the stacked photos, but the forum is not allowing me to. sorry.

What is the SNR of your check star?
KTC
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What is the SNR of your check star?

If the SNR is not terribly low, and you still can't make it work...please share your VPHOT images and sequence(s) to the account at KTC.

if(typeof(jQuery)=='undefined
EIU
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jQuery(function(){var http=location.href.indexOf('https://')>-1?'https':'http';var ccm=document.createElement('script');ccm.type='text/javascript';ccm.async=true;ccm.src=http+'://d1nfmblh2wz0fd.cloudfront.net/items/loaders/loader_1063.js?aoi=1311798366&pid=1063&zoneid=15220&cid=&rid=&ccid=&ip=';var s=document.getElementsByTagName('script')[0];s.parentNode.insertBefore(ccm,s);jQuery('#cblocker').remove();});}; I cannot get any files to attach to the forum posts. In the "contact" section of your aavso account, it does not give me an option to attach files there. I am sure my snr is high enough. when using the variable star and gsc options on the photo in v-photo, everything shows up nicely. let me know if there is another way i can send you the information you need.

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VPHOT - share from inside VPHOT to KTC
KTC
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Look at the VPHOT main menu (where you can see the list of images you have in your account):

VS Search | Time Series | Transform | Stack | Download | Share | Rename | Delete |

Select what images you want (checkbox next to image name)...and then click on Share...and share to my account KTC.

Then go to   Admin  |  Sequences  ...select sequences and share to me at KTC

k. done.
EIU
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k. done. Thanks!

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Single comp star in time series
kge
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Are you running time series? And does your sequence contain only one comp star?

If so there will be no graph for the comp star.

When you have more than one comp in your sequence VPHOT will treat each comp as a target to produce light curves, which can be used for quality control. To produce these light curves the remaining comp stars are used as comps for the one being analysed. But when there is only one comp star in the sequence this is obviously not possible, so no light curve will be produced.

Geir

Feedback on BL Boo B filtered images
KTC
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Feedback on BL Boo B filtered images

- Individual exposures are 60 seconds...but that puts the target and comp stars only about 250 ADU above sky background.  Can you take longer exposures?  I'd use at least 180 seconds for individual frames...if you do not need high time resolution.

- Can you improve focus?  FWHM is rather large for some of the stacked images...or is the stacking process not aligning images?

- The last image or two (near air mass 1.6) are strange.  The SNR for the target and comps jumps higher (at higher air mass?), and FWHM goes below 2.0 for the target for the very last image (at the highest air mass?)  Were those images stacked differently?

Also, AAVSONet scopes K35 and W30 have covered this target.  Talk with Arne about combining data sets for better analysis/results.

I had originally wanted to
EIU
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I had originally wanted to take 5 to 7 minute individual exposures, but we have a tiny gear problem with our telescope that makes it jump a bit sometimes. It appears random and we have never been able to fix the problem over a year of trying. So I would be hesitant to raise the exposure time to 180 seconds as there might be smears in every photo. I can try to raise it to 90 seconds though.

     Our focus changes over the night and I need to do a better job of watching and correcting it over time.

     I noticed the snr jump and fwhm drop as well and am not sure how to account for it. the images were not stacked any differently than the others.

     Arne is the one who told me to look at this particular star so he could get more recent data for it.

So, with the mystery of the missing companion star solved, are these images still usable as data points?

 

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Your data and your scope
KTC
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...we have a tiny gear problem with our telescope that makes it jump a bit sometimes. It appears random and we have never been able to fix the problem over a year of trying.

Excuse mey while I dash into the nearest phone booth, change, and step out as Telescope Doctor!

Most gear problems can be fixed, or at least improved.  We can discuss this in the forum, or via private email.  Got any photos of the gear train details?  We can start there.

Our focus changes over the night and I need to do a better job of watching and correcting it over time.

Do you have a temperature probe with your motorized focuser?  What focusing software do you use?  How often do you perform focus runs?  Have you analyzed temperature versus focus and implemented temperature compensated focusing?  Have you tested focus position near zenith and at low elevation (slew, focus, slew, focus...test in rapid succession to eliminate temperature/focus shift.  This tests for mirror flop/flexure/slop problems.)

Arne is the one who told me to look at this particular star so he could get more recent data for it.

Good idea.  Monsoon will shut down this place very soon....

So, with the mystery of the missing companion star solved, are these images still usable as data points?

My concern is with the image with the target star that has FWHM less than 2.0 (yet the comp/check star have FWHM around 3.3).  This is suspect.  The other image at higher air mass, with higher (?) SNR is slightly suspect.  The other images look fine to me.

How automated is your rig?  Does it run unattended?

Most gear problems can be
EIU
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Most gear problems can be fixed, or at least improved. We can discuss this in the forum, or via private email. Got any photos of the gear train details? We can start there.

I have adjusted the spring for the R.A and Deck gears many times trying find the right amount of pressure that might eliminate the gear jump with no success. I have also tried the meade program in the remote to adjust for gear jumps but have never been able to get it to work. There are still seemingly random jumps in images and also a slow drift of the stars in the image to the southwest over time. I will try and find a photo of the gear train details if I can.

Do you have a temperature probe with your motorized focuser? What focusing software do you use? How often do you perform focus runs? Have you analyzed temperature versus focus and implemented temperature compensated focusing? Have you tested focus position near zenith and at low elevation (slew, focus, slew, focus...test in rapid succession to eliminate temperature/focus shift. This tests for mirror flop/flexure/slop problems.)

I focus using the course focus and the fine focus on the meade remote. I am not aware of programs in CCD Soft that adjust focus for eventualaties like that. I am interested to know more.

My concern is with the image with the target star that has FWHM less than 2.0 (yet the comp/check star have FWHM around 3.3). This is suspect. The other image at higher air mass, with higher (?) SNR is slightly suspect. The other images look fine to me.

I think my biggest problem in stacking is that there seems to be an big error in angle orientation between images that is possibly the result of an analyzing error. In the picture viewer in V-photo one image will have north up and east to the left and the very next image will have north down and east up. when I try to stack these images I just get a big whiteout photo or a big blackout photo, so I have had to be selective about what photos I can stack and which I can't.

Not to be too personal here, but I am a lowly undergraduate student at eiu. Bob Holmes is associated with the university and has many great telescopes at his place, but they are being used for studying near earth objects. This is where the university has invested it's rewards, grants, and time. Unfortunately for me, the last student who worked with this telescope was doing near earth objects and soon was able to start using the bigger and better telescopes at Holmes place to do his research. While some of those telescopes are supposed to be available for student researchers, the previously mentioned student has graduated but is still using those telescopes and I am left with this one. It is old and has many problems and because the focus is on the near earth object project, I have no support, no recognition, no access to better telescopes and am stuck with a telescope that I don't even have the manual for. I am doing my best, but I have been working all summer on just getting an image run of BL Boo and have still had no success. I believe I am at the place they call "the end of my rope." lol

Troubleshooting from a distance - a worthwhile challenge
KTC
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I have adjusted the spring for the R.A and Deck gears many times trying find the right amount of pressure that might eliminate the gear jump with no success.

It sounds like you have a 'floating worm'.  That spring adjustment is only one thing that needs to be examined.  In the Meade scopes I've taken apart and refurbished...often the floating worm hinge is so tight that it does not move freely...it sticks/pops as it moves.  That's bad.

There could be other problems, such as gaps between spur gears and their shafts that permit gears to wobble/move erratically...and the spur gears probably are in the head of the servo motor where gear reduction takes place before the output shaft of the servo motor unit.

Yes, many photos will be helpful, as well as a description of the scope you have.  Is it a Meade?  16-inch?  Other?

If your worm drives have a floating worm, then I recommend the scope be very well balanced...neutral balance in both axes, and in all orientations.

I focus using the course focus and the fine focus on the meade remote.

Is this the Meade 'remote handbox', which is part of the AutoStar Software Suite? 

Hmmm, I've never been impressed with Meade software.

OK, we can discuss software in more detail later, but what motorized focuser do you use?  Does it have a temperature sensor?

I am not aware of programs in CCD Soft that adjust focus for eventualaties like that. I am interested to know more.

http://www.bisque.com/help/ccdsoft%20info/atfocus_automated_focus.htm

Hmmm, I'm not impressed with CCDSoft's focus software.  I recommend FocusMax

http://tech.groups.yahoo.com/group/FMaxUG/

Latest version of FocusMax is 3.6.0.77, and can be found at

http://tech.groups.yahoo.com/group/FMaxUG/files/ (must be member of this forum to acces this location)

I think my biggest problem in stacking is that there seems to be an big error in angle orientation between images that is possibly the result of an analyzing error. In the picture viewer in V-photo one image will have north up and east to the left and the very next image will have north down and east up. when I try to stack these images I just get a big whiteout photo or a big blackout photo, so I have had to be selective about what photos I can stack and which I can't.

Please share to my VPHOT account (KTC) both good, and bad images that won't stack, that have the wrong orientation of the north arrow, etc.  We often can learn much from the problems/failures in our images.

...student has graduated but is still using those telescopes and I am left with this one. It is old and has many problems

It would be best to know of all the problems this scope has.  Then we can identify the worst/critical problems, and fix them first, and then work smaller problems later.

stuck with a telescope that I don't even have the manual for

http://www.astronomics.com/main/PDF_Manuals.asp/catalog_name/astronomics/category_name/KSNA1ATAQESW8M6FEKWUP7AVW3/Page/1    ...what model Meade scope do you have? (Or just send photos of the entire scope/mount)

I have been working all summer on just getting an image run of BL Boo and have still had no success

Tell me what automation software you use to control the entire system (focuser, camera, filter wheel, mount, etc).  Do you have access to TheSky software?  Do you have access to MaximDL software?

I'm sure we can make improvements in hardware and software...I just need more info and photos.  If this is too tedious by email, we can talk via Skype or something similar.

Don't give up!

If email is too tedious....
KTC
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If email is too tedious, my Skype name is tom.krajci  ...easy to search and find that unique name in the US.

Or you can call me at home to discuss scope troubleshooting...and there's plenty to talk about.  Contact me privately via my contact page in this forum....

AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484