Re: AP 1200 - bump against the counterweight shaft
Wiggins, Rick
Hi Werner,
I too have tried moving my AP1200 with cranial persuasion. I have found that the hand controller is much more pleasant and accurate! Mine happened when setting up the mount and during the adjustment I had removed the foam that is usually wrapped around the weights and end of shaft. In my case the new counterweight stop screw (with sharp squared-off edge caught my forehead and machined a new aging line into my head complete with crimson fountain. I nearly passed out and luckily my friend administered first aide and after an hour or so, could resume work. Thanks, Rick --- In ap-gto@..., "werner.pribil" <werner.pribil@...> wrote: shaft pointed down to the ground in a northward direction.at the end of the counterweight shaft. In the first moment I did notknow what had happened and I had to sit down immediately. Now I have a1200, especially the worm and wheel adjustments of R.A. or the bothDec.lock knobs. Or is this collision no problem for the AP 1200.
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Re: New rig
Wiggins, Rick
Hi Hap,
Are you sure that it is a mirror lock? The Celestrons have a focus lock, but to my knowledge, there is no mirror lock available. My understanding is that it takes a significant amount of work to install a mirror locking mechanism on a Celestron which includes penetrating the back plate, installing screws that push on the mirror mount, etc. Thanks, Rick --- In ap-gto@..., "Hap Griffin" <lgriffin@...> wrote: of the mirror lock/focuser. But it seems to work great. Once I get themirror in a location where the Feathertouch has a good range with my camera,I just lock it and it seems to stay put OK.Feathertouch fullfocuser on mine for years (not the knob replacement kind, the trying toblown 2" modified crayford type) and eventually gave up on haveget the mirror to sit still. It has sat in a case ever since. I teh backalways contemplated taking it apart and adding three bolts in siliconedplate of the OTA, spaced at 120 degrees, with matching cups withto the back of the primary that the mirror would draw back onto hadenough force to hold it firmly yet not enough to distort. Never mirrorthe time to get around to it though. If someone has a decent Time,lock that actually works, it would be worth having a look at. itlgriffin@ writes:So, here it is...all three scopes on the AP-1200. Believe champ withor not,everything balances nicely and the mount tracks like a faintover a100-pound load. Gotta love the AP-1200 for shear quality!Impressive looking setup. Nothing wrong with a C11 for small FeathertouchgalaxyThis carbon fiber C11 has a mirror lock and an externalimaging. thefocuser. It held focus for over three hours last weekend with temperature dropping about 20 degrees.
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Re: Dec Autoguiding problem
Roland Christen
In a message dated 6/1/2008 6:03:24 PM Central Daylight Time,
capitoladude@... writes: The dec oscillation problem with my AP900 is still ugly as ever.Your tests of the Dec axis show nothing out of the ordinary as far as the mechanics are concerned. If it takes 3 seconds for the Dec axis to reverse when pressing the N-S button at 1x rate, then I would say that your gear mesh is a bit loose. However, this should not cause wild swings back and forth in Dec. Maybe I misread your test of the Dec axis and it does not take a full 3 seconds to reverse. Of course, you would be the one to know since you were there doing the test and I can only interpret what the result was. Normally, wild swings are caused by a loop gain greater than 100% (i.e. the correction commands sent to the mount are larger than the error). This will result in limit cycling as you have experienced. You can see whether the loop gain in Dec is too large by looking at the parameter numbers in the Dec axis. If the parameter number after calibration is always smaller in Dec than RA (calibration near the celestial equator) then chances are that your loop gain will be larger than 100%. In that case the mount will always be asked to overcorrect in Dec with the resultant oscillations. Two ways to fix this, if that is the cause. 1) increase the parameter number to be approximately equal to the RA number. 2) reduce the agressiveness in the Dec axis below 100%. Keep lowering it until the axis becomes stable. Try setting your Min move to 0 and Max move to 0.3 seconds and then adjust the agressiveness until the axis is stable. Also be sure that the backlash adjust in the keypad and in Maxim has been set to zero when you are guiding. Roland ************** Get trade secrets for amazing burgers. Watch "Cooking with Tyler Florence" on AOL Food. (http://food.aol.com/tyler-florence?video=4& ?NCID=aolfod00030000000002)
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Re: Flexure Solved
Roland Christen
In a message dated 6/1/2008 11:08:31 AM Central Daylight Time,
hewholooks@... writes: Here's the M92 that I got since solving the issue:Excellent shot. Surprising how well a consumer camera does on deep sky. Rolando ************** Get trade secrets for amazing burgers. Watch "Cooking with Tyler Florence" on AOL Food. (http://food.aol.com/tyler-florence?video=4&?NCID=aolfod00030000000002)
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Mach1 on a DM-6 tripod? (and hello)
richardm123uk <richard.molyneux123uk@...>
Hello all,
This is my first post on this group. I am on the waiting list for a Mach1 and was wondering if I can mount it on my DM-6 tripod or am I going to have to purchase another tripod when my number comes up?. Cheers, Richard
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Re: Dec Autoguiding problem
Steve Peters
--- In ap-gto@..., chris1011@... wrote:
One more thing: On the AP website under Technical Support, scrolldown until you get to the heading: "Mount Troubleshooting - For additionalon: "Characterizing the Dec Axis Motions (09-15-03) - PDF document." Follow the instructions inthis PDF to determine whether your Dec axis is moving properly. Theinstructions should be plain enough for you to determine if you have a mechanicalproblem in this axis. If so, then we can go to the next step.Hi Roland, The dec oscillation problem with my AP900 is still ugly as ever. Last night after trying to image and failing because of the wild dec fluctuations I did some testing and recorded some results as you had suggested. Again, my setup is AP160 refractor on AP900 GTOCP3 (purchased new in 2007), 100mm f/6 guide scope with Orion StarShoot DSI camera for guiding, MaxIm DL software for guiding and image capture. First, I characterized the dec axis motions following the procedure on the AP website. I didn't use the track log, but here's what I found in three separate tests. I started at a "middle" position of X=16, Y=16, then used the North button to move the star to Y=8. then I pulsed the South button in ~ 1 second pulses. the results show the movement in the Y axis; X did not change. Test 1 Test 2 Test 3 Start 8 8 8 Pulse 1 7 8 7 Pulse 2 7 9 7 Pulse 3 10 11 9 Pulse 4 14 14 12 Pulse 5 17 16 14 Pulse 6 -- -- 17 So, it took three pulses before the star started moving south in each test. Do these results suggest anything out of the ordinary? Next, I did the following things. I have posted some screen shots in the Files area that I will refer to. They're in a folder named AP900 Dec Tests, Files from Steve Peters. I should also note that I polar aligned using the polar scope only. However, the polar scope itself was aligned (usingt the thre tiny setscrews) a couple of sessions ago AFTER I had done a drift alignment, so it is pretty spot on. Guiding rate was 1x. 1. Calibrated on a star in the eastern sky. 2. Guided on a nearby star. With dec guiding turned on, the dec error graph was flat for 5 minutes (I didn't take a screen shot of that). As I've stated before, the mount guides well in the easter part of the sky. It's in the west and sometimes the south where the oscillation pattern occurs. 3. Turned off both dec (Y) directions in MaxIm. I began this at 410 time point (see DecOFFbegin_east.jpg). Almost 5 minutes later at 690, the error graph is essentially flat (DecOFFend_east). 4. At time point 900, I turned both dec directions back on (decON_east). After a liottle more than 3 minutes, you can see maybe a half pixel of downward drift. I realized after all this that you had said to turn on one Y direction and see what happens. I neglected to do that, so I will have to go back and do it if having that information would still be useful to you. 5. Then I slewed the telescope to the western sky and checked "pier flip," got a guide star and started tracking at time point 1440 with dec guiding on(see decON_west). You can see the big +2 and -2 pixel oscillations. 6. Turned both dec guiding directions off at 1800 (decOFF_west). The dec error graph flattens out. 7. Then, to see if calibrating in the west helped, I calibrated on a star, then guided on the same star. With dec guiding on, I started at time point 2370 (decON_west_calib). Again, bad oscillation. 8. At 2670, turned both dec directions off (decOFF_west_calib). The oscillation stops. There is a slight upward drift of 1.5 pixels after 5 minutes (decON2_west_calib). So that's pretty much what I've been struggling every time out since I bought this mount. I've tried numerous tweaks of settings, gear mesh adjustment, consulting with my imaging friends, etc., all to no avail. Let me know your thoughts. Next weekend I may have an opportunity to swap my mount for a friend's AP900. The rest of my system would be the same, so I will see if there's any difference in dec behavior using his mount. Another test I could do (on a different night) would be to try a different guide camera. And of course I could try a different guiding program, such as PHD Guiding (although that program doesn't have an error graph, just a numerical tracking log, I believe). I will be interested in your comments on the above tests and what you suggest I try next to get the dec to function properly. Thanks, Steve Peters
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Re: Flexure Solved
Jerry Lodriguss
Hi Hunter,
That is really excellent. Jerry At 12:08 PM 6/1/2008, you wrote: Thanks everyone for your advice with my flexure problems.A Guide to Astrophotography with Digital SLR Cameras http://www.astropix.com/GADC/GADC.HTM . . . . . . . . . . .
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Re: Flexure Solved
Richard Crisp
glad the suggestion worked
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only with rare exceptions have I seen a side by side work well enough to yield round stars. I strongly recommend not using that configuration. I have seen it work fine with a pair of FCT76 taks side by side... but they are short and have little polar moment of inertia
----- Original Message -----
From: hewholooks To: ap-gto@... Sent: Sunday, June 01, 2008 9:08 AM Subject: [ap-gto] Flexure Solved Thanks everyone for your advice with my flexure problems. As you recall, I had gotten the new Mach1 and since the guiding was so good, I could now determine that my elongated stars were flexure and not the mount. I was advised to junk my side-by-side saddle arrangement and so I went piggyback with my ST80 on top of my C9.25 with some ADM rails and rings. Frankly, I was worried about moving the center of gravity out farther with all that scope and weight on the Mach1, but it has not batted an eye. I didn't expect to rid myself of all the flexure, since I was using the SCT, and maybe I didn't, but it's all but disappeared. http://hwilson.zenfolio.com/p782801820/ Now I have tiny little round stars, even with an SCT, thanks to the great guiding and the advice from here. Here's the M92 that I got since solving the issue: http://tinyurl.com/69edga Thanks again, Hunter
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Flexure Solved
hewholooks
Thanks everyone for your advice with my flexure problems.
As you recall, I had gotten the new Mach1 and since the guiding was so good, I could now determine that my elongated stars were flexure and not the mount. I was advised to junk my side-by-side saddle arrangement and so I went piggyback with my ST80 on top of my C9.25 with some ADM rails and rings. Frankly, I was worried about moving the center of gravity out farther with all that scope and weight on the Mach1, but it has not batted an eye. I didn't expect to rid myself of all the flexure, since I was using the SCT, and maybe I didn't, but it's all but disappeared. http://hwilson.zenfolio.com/p782801820/ Now I have tiny little round stars, even with an SCT, thanks to the great guiding and the advice from here. Here's the M92 that I got since solving the issue: http://tinyurl.com/69edga Thanks again, Hunter
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Re: AP 1200 - bump against the counterweight shaft
Mark Jenkins
Hello Werner and welcome to the AP-Counterweight/Shaft bump on the
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head club! ;-) I would be worried about your head more than the mount. Mark
On Jun 1, 2008, at 8:46 AM, werner.pribil wrote:
Hello !
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AP 1200 - bump against the counterweight shaft
werner.pribil
Hello !
Yesterday I had my first observing session with my AP 1200 (the tracking rate at the main menu of the keypad was sidereal). The telescope was pointed in eastward direction, so the counterweight shaft pointed down to the ground in a northward direction. At the end of my session I picked up a book from the ground and when I stood up I striked with my head against the safety stop at the end of the counterweight shaft. In the first moment I did not know what had happened and I had to sit down immediately. Now I have a little bump on my head. Can somebody tell me if this little accident can damage my AP 1200, especially the worm and wheel adjustments of R.A. or the both Dec.lock knobs. Or is this collision no problem for the AP 1200. Werner
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Re: New rig
observe_m13
--- In ap-gto@..., chris1011@... wrote:
OK, I had a look at the few pictures I could find of a disassembled C-11 and that ring is quite small other than for the tab that attaches to the focuser. I could carefully mill out a bit of the lip material at 120 degree spacings to provide a bit more of a landing spot and then drill a shallow dimple in that flat spot for the tip of the bolt to land into. The other option might be to machine and epoxy on a somewhat wider ring to provide more surface area to work with. Thanks for the idea. It certainly makes a lot more sense to push on the metal. Rick.
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Re: New rig
Hap Griffin
I picked up the C11 used on Astromart, so I don't know the origin of the mirror lock/focuser. But it seems to work great. Once I get the mirror in a location where the Feathertouch has a good range with my camera, I just lock it and it seems to stay put OK.
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Hap
----- Original Message -----
From: "Rick K" <JunkMailGoesHere@...> To: <ap-gto@...> Sent: Thursday, May 29, 2008 6:49 PM Subject: [ap-gto] Re: New rig Hi Hap,
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Re: New rig
Hap Griffin
We have a place known as "Metal Supermarket" nearby that sheared the plate. I only had to do a bit of touchup with a file.
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Hap
----- Original Message -----
From: "Morgan Spangle" <msfainc@...> To: <ap-gto@...> Sent: Thursday, May 29, 2008 7:56 PM Subject: [ap-gto] Re: New rig Hi Hap,
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Re: Pulse Guide
Larry Phillips
Thanks Jim, that is good to know.
Larry --- In ap-gto@..., "jfellerone" <jfellerone@...> wrote: Rbofocus, VNC for remote control, and other software. Compatability is not anMaxim serialtoautoguide? Will there be any software conflicts. I understandthat touse Pulse Guide and TheSky simultaneously I would need two aloneconnections. I also think I understand how to use it stand to beadviceable to more accurately track and to use the PC to control themountrather than the hand controller. Thanks in advance for anyyoumay have.
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Re: AP1200GTO Question
starclusterseeker <classicstone9474@...>
--- In ap-gto@..., chris1011@... wrote:
No clickingproblem here. However the Declination gears make a noise "click"Just put a bit of grease on the spur gears in the motor box. The sound is normal and may or may not go away with the grease. It hasno effect otherwise.NCID=aolfod00030000000002)
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AP1200GTO Question
starclusterseeker <classicstone9474@...>
Hi Group, My plans this weekend is disasseble my telescope,and
counterweights & etc. and grease the mating parts of the RA/DEC. No problem here. However the Declination gears make a noise "click" and while looking thru the eyepiece while slewing @ .25 & with the star moving in the eyepiece it has a jerking motion. When I increase the speed of the slew. (BY PUSHING ON BUTTON 6) The jerking goes away but at the beginning i still hear the click.While I have this disassembled I sure would like to correct this as well. Can anybody help me My telescope is balanced and abot 6 months ago I did adjust the mesh of the gears in both RA & DEC and also greased them. Hopefully nothing is broke. Thanks,
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Re: Pulse Guide
jfellerone <jfellerone@...>
I use pulse guide in a semi-remote situation. Primary uses are for
centering, changing rates, meridian offset, etc. I find it useful. I also use The Sky, Maxim, CCD inspector, Photoshop, PemPRO, Rbofocus, VNC for remote control, and other software. Compatability is not an issue if you have enough serial ports. If not you have to disconnect One of the programs to use another. Jim --- In ap-gto@..., "Larry Phillips" <llp41astro@...> wrote: wondering hownowI make use of Pulse Guide by integrating it with the software I imaging?use. Could someone explain how to use Pulse Guide while I amintegrateusing Maxim, CCD Commander, FocusMax, and TheSky. Can I theadvicebenefits of Pulse Guiding with these? That is, still allow Maximtoautoguide? Will there be any software conflicts. I understandthat touse Pulse Guide and TheSky simultaneously I would need two serialto be youmay have.
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Re: AP1200GTO Question
Roland Christen
In a message dated 5/30/2008 9:57:26 AM Central Daylight Time,
classicstone9474@... writes: Hi Group, My plans this weekend is disasseble my telescope,andJust put a bit of grease on the spur gears in the motor box. The clicking sound is normal and may or may not go away with the grease. It has no effect otherwise. Rolando ************** Get trade secrets for amazing burgers. Watch "Cooking with Tyler Florence" on AOL Food. (http://food.aol.com/tyler-florence?video=4&?NCID=aolfod00030000000002)
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Re: AP160-AP1200GTO: Exoplanet Busters!
ayiomamitis
--- In ap-gto@..., "Bert Katzung" <katzung1@...> wrote:
Thanks Bert and Rolando! Having nailed an exoplanet which leads to a dimming of the parent star by 13 mmags, the next question is how much lower can I go and still capture such a transit. We have lots (!) of exoplanets associated with reductions around 9-11 mmag and which I will pursue next. If successful, we will raise the bar even further with other examples involving a 5-7 mmag change in the dimming of the associated parent stars. Having such a premium scope and mount really allows one to pursue projects which are very aggressive in nature and seemingly beyond reach. Who would have expected a "humble" 6.3" refractor detecting a 13 mmag change in the brightness of a star hosting an exoplanet? Those actively involved with this kind work invariably use C14's (ex. Bruce Gary, Ron Bissinger, Tonny Vanmunster) and, in one particular case, a 32" instrument (Cindy Foote). Anthony. Bert
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