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How much counterweight?
Bob Holzer <b.holzer@...>
Hi Folks:
I think I have a Tak BRC-250 coming, it weighs 34 pounds, and am wondering if some one can guesstimate the counterweights I will need for it on my AP900. I may also mount my FSQ-106 on top of it. My imaging equipment is a good 10lb too. If someone has something close in size and weight I would appreciate knowing how much weight you are using. I already have two Casady 14.lb weights, I wonder if one more 21.7lb will work? Thanks, Bob
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Re: First images with AP1200 GTO
Roland Christen
In a message dated 6/22/2007 2:01:14 PM Central Daylight Time,
ayiomami@otenet.gr writes: Because the large circles move from master image to master image, weOnly way to know is to remove a filter and shoot through the air itself. Possibly the dust is on the field flattener lens or telecompressor. Yes, the further away from the film plane, the larger the dark circles will be. However, once you get to the objective lens itself, you can have all kinds of dust or even large central obstruction, and nothing at all will appear on the image - but of course you knew that, yes? Rolando ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
Roland Christen
In a message dated 6/22/2007 11:23:05 AM Central Daylight Time,
ayiomami@otenet.gr writes: The concern I have with my set is the nice big circles whichThat's caused by dust particles. Rolando ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
Roland Christen
In a message dated 6/22/2007 5:40:49 AM Central Daylight Time,
ayiomami@otenet.gr writes: It is my understanding that SBIG's filters are produced by CustomMy ST10XE is one of the first ones. It is quite old, and the filters are not fully multi-coated on all surfaces. I don't care who made these filters. If one surface is left without coatings, there will be 4% reflection from that surface, which will indeed cause a 4% ghost image. Rolando Rolando ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
ayiomamitis
Rick,
toggle quoted messageShow quoted text
I have SBIG's standard CLRGB filters and I do not experience such a problem. I image a lot of clusters (ie. lots of starry fields) and I have never encountered such a problem not even once. Is it possible that slight ambient temperature changes are affecting your focus point, thus giving you the false impression that the filters are doing something? I amvery careful of the ambient temperature and do refocus if necessary. Anthony.
--- In ap-gto@yahoogroups.com, "Rick Wiggins" <rickwiggins@...> wrote:
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Re: First images with AP1200 GTO
ayiomamitis
--- In ap-gto@yahoogroups.com, chris1011@... wrote:
filters in my ST10 camera cause multiple reflection ghosts near bright stars. Idon't know who makes these filters for SBIG, but they are not of thequality level of the Baader series. In my STL11K camera I have installed 3 of thenarrow band 2" Rolando, It is my understanding that SBIG's filters are produced by Custom Scientific (at least the LRGB ones). Anthony.
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Re: First images with AP1200 GTO
elraeburn <eraeburn@...>
--- In ap-gto@yahoogroups.com, chris1011@... wrote:
I have been testing the Baader filters for the last week under allThis raises an issue I've been wanting to ask about for some time: how do the Baader RGB filters perform for CCD imaging? The transmission curves look to me like they are not designed for this application (unequal coverage across the visual spectrum). How do they handle the "Astrodon Teal Criterion" (blue and green transmission curves intersecting at the OIII line)? Also, is it true they are available only in 1.25" models? -Eric
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Re: GPS on a German Equatorial Mount
michael mcdermott <classicstone9474@...>
I am curious to know how the AP mounts are able to get the time and location from the keypad/mount? There is a feature now isn't there?- Michael
John Stone <johns@ks.uiuc.edu> wrote: I'm late replying to this, but from my point of view, the GPS is mainly useful as an accurate time reference. People doing minor planet work like to have accurate times on their exposures. But in that use case, the user has a computer involved already, and can thus attach the GPS to the computer which is what they probably want to do anyway..For normal visual observing I don't see any real benefit. I would vote that this feature not be added unless you can add it as an _optional_ startup mode/phase in the firmware for the existing mount controllers (e.g. a firmware upgrade for CP3 mount controllers). If implemented as new firmware that just "listens" on one of the serial ports, that might be useful for some people. One could make a small microcontroller box to interface a GPS to an AP mount for a modest cost if people are really wound up and absolutely have to have GPS with their AP mount. I'm sure a PIC or a BASIC STAMP chip could do this pretty trivially. Parsing NMEA packets from a GPS is easy. Such a box could be used even with the older mounts. Cheers, John Stone --- In ap-gto@yahoogroups.com, chris1011@... wrote: the Gemini GoTo system. I realize that GPS is vital for Alt-Az mountings, sincetracking rate of any object in the sky is variable and directly affected by youraligned GEM is always fixed at sidereal, I question the need for this addedcomplication to the system (another thing to go wrong out in the field). Myself, I thinkof it like having anti-lock brakes on a speedboat, however Marj is totallyconvinced that we will need this vital bit of technology in order to not be leftbehind by the competition.align)? Any thoughts from the advanced users out there?
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Re: GPS on a German Equatorial Mount
John Stone <johns@...>
I'm late replying to this, but from my point of view, the GPS is
mainly useful as an accurate time reference. People doing minor planet work like to have accurate times on their exposures. But in that use case, the user has a computer involved already, and can thus attach the GPS to the computer which is what they probably want to do anyway..For normal visual observing I don't see any real benefit. I would vote that this feature not be added unless you can add it as an _optional_ startup mode/phase in the firmware for the existing mount controllers (e.g. a firmware upgrade for CP3 mount controllers). If implemented as new firmware that just "listens" on one of the serial ports, that might be useful for some people. One could make a small microcontroller box to interface a GPS to an AP mount for a modest cost if people are really wound up and absolutely have to have GPS with their AP mount. I'm sure a PIC or a BASIC STAMP chip could do this pretty trivially. Parsing NMEA packets from a GPS is easy. Such a box could be used even with the older mounts. Cheers, John Stone --- In ap-gto@yahoogroups.com, chris1011@... wrote: the Gemini GoTo system. I realize that GPS is vital for Alt-Az mountings, sincetracking rate of any object in the sky is variable and directly affected by youraligned GEM is always fixed at sidereal, I question the need for this addedcomplication to the system (another thing to go wrong out in the field). Myself, I thinkof it like having anti-lock brakes on a speedboat, however Marj is totallyconvinced that we will need this vital bit of technology in order to not be leftbehind by the competition.align)? Any thoughts from the advanced users out there?
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Re: First images with AP1200 GTO
peturnielsen
and price ?
astrodon (6nm) is $695 vs baader (7nm) is $335 !!(for STL 11000) p --- In ap-gto@yahoogroups.com, kgkirkley@... wrote: kinds of H-asky conditions. I do not see any halos around any bright stars. My stars. Maybe Iimages but go onlyam RGB filterson what I have heard from others). I do know that several of my I don'tin quality levelknow who makes these filters for SBIG, but they are not of the narrow bandof from his2" avoided unlesscover glass and filter rear surface, something that can't be theRoland:
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Re: [PHISHING]: Re: Re: First images with AP1200 GTO
bcoote37
Hi Rolando,
toggle quoted messageShow quoted text
I have been looking back at recent images with my STL11K and Astrodon filters. How much halo is visible on stars certainly depends on how much stretching of data is used to make them more visible. Very bright stars certainly induce strong reflections and green is by far the worst on my system. I think interline chips are probably indirectly involved as with the full frame chips the bright stars usually induced blooms which required processing to remove. As a result I anyway avoided overlong integrations with my ST8E NABG . Regards, Brian http://www.bcoote-astro.com/default.htm
----- Original Message -----
From: chris1011@aol.com To: ap-gto@yahoogroups.com Sent: Friday, June 22, 2007 5:47 AM Subject: [PHISHING]: Re: [ap-gto] Re: First images with AP1200 GTO --------------------------------------------------------------------------------------------------- Panda Antivirus + Firewall 2007 has detected that this email could be spoofed Take maximum precautions, as spoofed emails could be the sign of a fraud attempt. --------------------------------------------------------------------------------------------------- In a message dated 6/21/2007 2:32:22 PM Central Daylight Time, stuart.j.heggie@sympatico.ca writes: > Roland, the SBIG filters are from Custom Scientific I believe. I get very > strong halos from my green Astrodon. I had thought it was due to the fast > f-ratio I was shooting with the scope I've had till now. > I have an older SBIG ST10E which has very strong multiple reflections form the green filter and fainter ones from the blue. These filters have no coatings on one side, so about 4% of the energy keeps bouncing between front and rear surface. I do not know where SBIG got those filters. The STL11K camera that I got from Ray Gralack have Custom Scientific RGB filters, he tells me. I have not had any reflection problems with them. Rolando ************************************** See what's free at http://www.aol.com. --------------------------------------------------------------------------------------------------- Panda Antivirus + Firewall 2007 has detected that this email could be spoofed Take maximum precautions, as spoofed emails could be the sign of a fraud attempt. ---------------------------------------------------------------------------------------------------
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Re: First images with AP1200 GTO
Tom Davis
I know this would be difficult to do, but it would be very
illustrative to see a same target, same scope, same camera but different filters (especially RGB) side by side image comparison. I currently have A-dons and unfortunately sold my SBIG/CS filters. Tom --- In ap-gto@yahoogroups.com, chris1011@... wrote: get very the faststrong halos from my green Astrodon. I had thought it was due to reflections formf-ratio I was shooting with the scope I've had till now.I have an older SBIG ST10E which has very strong multiple the green filter and fainter ones from the blue. These filters haveno coatings on one side, so about 4% of the energy keeps bouncing between frontand rear surface. I do not know where SBIG got those filters. The STL11Kcamera that I got from Ray Gralack have Custom Scientific RGB filters, he tellsme. I have not had any reflection problems with them.
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Re: First images with AP1200 GTO
Wiggins, Rick
Hi Guys,
It is well known (meaning I personally know more than ten imagers that have had this problem and it is regularly discussed on several imaging forums) that the blue and green filters cause halos in RGB images. Many people believe that they are very bad in the AstronDon filters. They definetly happen with the AstroDons. I don't have enough data on non-AstroDon filters to do an objective comparison. It is obviously more prevalent around bright stars and is worse the more you stretch the image. I have not seen halos with narrow band filters of any brand. Thanks, Rick --- In ap-gto@yahoogroups.com, chris1011@... wrote: kinds of sky conditions. I do not see any halos around any bright stars. MyH-a images are very sharp with no reflections or ghost images around anystars. Maybe I am mistaken about Astrodon filters (I have not tested them myself,but go only on what I have heard from others). I do know that several of myRGB filters in my ST10 camera cause multiple reflection ghosts near bright stars.I don't know who makes these filters for SBIG, but they are not of thequality level of the Baader series. In my STL11K camera I have installed 3 of thenarrow band 2" Baader filters and the images they produce are super nice. AllBaader filters have high grade multi-layer coatings on them to insure freedomfrom reflections.from his cover glass and filter rear surface, something that can't beavoided unless the coverglass is coated with a multi-layer.
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Re: First images with AP1200 GTO
Stuart Heggie <stuart.j.heggie@...>
Roland, the SBIG filters are from Custom Scientific I believe. I get very strong halos from my green Astrodon. I had thought it was due to the fast f-ratio I was shooting with the scope I've had till now.
Stuart ============================================================ From: chris1011@aol.com Date: 2007/06/21 Thu PM 02:37:23 EDT To: ap-gto@yahoogroups.com Subject: Re: [ap-gto] Re: First images with AP1200 GTO In a message dated 6/21/2007 12:38:25 PM Central Daylight Time, kgkirkley@aol.com writes: you say the Baader filter(s?) doI have been testing the Baader filters for the last week under all kinds of sky conditions. I do not see any halos around any bright stars. My H-a images are very sharp with no reflections or ghost images around any stars. Maybe I am mistaken about Astrodon filters (I have not tested them myself, but go only on what I have heard from others). I do know that several of my RGB filters in my ST10 camera cause multiple reflection ghosts near bright stars. I don't know who makes these filters for SBIG, but they are not of the quality level of the Baader series. In my STL11K camera I have installed 3 of the narrow band 2" Baader filters and the images they produce are super nice. All Baader filters have high grade multi-layer coatings on them to insure freedom from reflections. It may also be that the original poster's reflections are coming from his cover glass and filter rear surface, something that can't be avoided unless the coverglass is coated with a multi-layer. Rolando ************************************** See what's free at http://www.aol.com. ============================================================
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Re: First images with AP1200 GTO
Kent Kirkley
In a message dated 6/21/07 1:42:04 PM, chris1011@aol.com writes:
Roland: Thanks for the clarification. Kent ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
Roland Christen
In a message dated 6/21/2007 2:32:22 PM Central Daylight Time,
stuart.j.heggie@sympatico.ca writes: Roland, the SBIG filters are from Custom Scientific I believe. I get veryI have an older SBIG ST10E which has very strong multiple reflections form the green filter and fainter ones from the blue. These filters have no coatings on one side, so about 4% of the energy keeps bouncing between front and rear surface. I do not know where SBIG got those filters. The STL11K camera that I got from Ray Gralack have Custom Scientific RGB filters, he tells me. I have not had any reflection problems with them. Rolando ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
Roland Christen
In a message dated 6/21/2007 12:38:25 PM Central Daylight Time,
kgkirkley@aol.com writes: you say the Baader filter(s?) doI have been testing the Baader filters for the last week under all kinds of sky conditions. I do not see any halos around any bright stars. My H-a images are very sharp with no reflections or ghost images around any stars. Maybe I am mistaken about Astrodon filters (I have not tested them myself, but go only on what I have heard from others). I do know that several of my RGB filters in my ST10 camera cause multiple reflection ghosts near bright stars. I don't know who makes these filters for SBIG, but they are not of the quality level of the Baader series. In my STL11K camera I have installed 3 of the narrow band 2" Baader filters and the images they produce are super nice. All Baader filters have high grade multi-layer coatings on them to insure freedom from reflections. It may also be that the original poster's reflections are coming from his cover glass and filter rear surface, something that can't be avoided unless the coverglass is coated with a multi-layer. Rolando ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
Kent Kirkley
In a message dated 6/21/07 12:13:55 PM, chris1011@aol.com writes:
Roland: I responded to your post, with wonderment, some days ago where you mentioned that Astrodon filters caused halos. And, now you say the Baader filter(s?) do not cause any halos. This is the first I have heard of this 'situation', while halos have been evident since the beginning of their use in ccd imaging, I thought all filters produced some level of halos, especially with faster optical systems. I also thought all filter manufacturers anti-reflection coated their filters. So what is unique about the Baader's? Is Baader producing only the Ha or a complete line of LRGB, Ha, etc. filters? Kent Kirkley ************************************** See what's free at http://www.aol.com.
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Re: First images with AP1200 GTO
Roland Christen
In a message dated 6/20/2007 8:00:49 PM Central Daylight Time,
peturnielsen@yahoo.com writes: do all H-alpha filters cause halo (i'm looking to buy one and wasI use the Baader 2" filter now. It does not cause any halos. Rolando ************************************** See what's free at http://www.aol.com.
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B343 Dark nebula in Cygnus - LLRGB 4 hrs total exposure
ayiomamitis
Dear Group,
With Cygnus slowly getting into good position for imaging, there is a wide variety of goodies it provides for the interested observer and imager. Given the plethora of Barnard dark nebulae it offers, I thought I would try my hand with one of the largest such objects just north of the bright star Sadr. More specifically, I pursued B343 which lies within a couple of degrees just north of Sadr. For an image based on four hours total exposure, I kindly direct you to http://www.perseus.gr/Astro-DSO-Nebulae-Dark-B343.htm . This is my first attempt at a dark nebula and I would welcome all feedback. I have checked around and cannot find any reference images for comparison B343 ... if someone has pursued this particular object, I would love to see your results. Clear skies! Anthony.
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