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Apology to the polar alignment scope
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Dear Polar Alignment Scope, I am sorry for bad-mouthing you all this time My hubris at deep space imaging and use of electronically assisted polar alignment from sharpcap and polemaster etc. had me believe you were outdated and useless for imaging Then the Comet Neowise arrived. I realized you were the only way i could quickly and accurately polar align in the field, and still have enough time to image the comet.? ?? So please, Polar Alignment Scope, accept my apology. I realize that even in this age of computers, you can still play an important role for imaging : :-) Brian? Brian Valente portfolio |
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Beautiful image, Brian. The close up shows real nice structure in the tail and the green of the coma really shows through. Two of mine I am happy with: |
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Love that first shot Arun - separation of the ionized gas from the dust tail the second one, the link wasn't working? On Mon, Jul 27, 2020 at 11:20 AM Arun Hegde <arun.k.hegde@...> wrote:
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Brian? Brian Valente portfolio |
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oh there it is! On Mon, Jul 27, 2020 at 11:23 AM Arun Hegde <arun.k.hegde@...> wrote:
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Brian? Brian Valente portfolio |
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Brian
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It takes a big man to admit using stone age tools! (I have too). But seriously, if you've been to a star party and whip out that laptop to use polemaster, PhD, sharpcap, et al, you are less welcome than a skunk. Chuck -----Original Message-----
From: Brian Valente <bvalente@...> To: Losmandy_users <[email protected]> Sent: Mon, Jul 27, 2020 11:10 AM Subject: [Losmandy_users_io] Apology to the polar alignment scope Dear Polar Alignment Scope,
I am sorry for bad-mouthing you all this time My hubris at deep space imaging and use of electronically assisted polar alignment from sharpcap and polemaster etc. had me believe you were outdated and useless for imaging Then the Comet Neowise arrived. I realized you were the only way i could quickly and accurately polar align in the field, and still have enough time to image the comet.? ?? So please, Polar Alignment Scope, accept my apology. I realize that even in this age of computers, you can still play an important role for imaging : :-) Brian? Brian Valente portfolio |
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That's the best image I have seen so far Brian.? I have not seen another image with the wavy details in the tail.
How did you track the comet for such a long exposure?? Did you use the autoguider to track it? Also, I was wondering, where the star trails went.? Then I noticed some streaks in the tail and zoomed in, there they were, you removed them quite well, barely visible.? How did you remove them?? I suppose in the tail it could be done manually.? The stars look like they were copied back in from a sidereal tracking image. Altogether great work! |
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HI Henk >>>That's the best image I have seen so far Brian.? I have not seen another image with the wavy details in the tail. Thank you - my original processing did not include these details, but when I saw other image and realized it was possible, i went back and teased out some of those remarkable details.? >>How did you track the comet for such a long exposure?? Did you use the autoguider to track it? no autoguiding, just 30 sec exposures on a D500 w/ 600mm f4 lens with standard sidereal tracking. It was far too long of a lens, I wish?i had brought a 135-200mm. >>>Also, I was wondering, where the star trails went.? Then I noticed some streaks in the tail and zoomed in, there they were, you removed them quite well, barely visible.? How did you remove them?? I suppose in the tail it could be done manually.? The stars look like they were copied back in from a sidereal tracking image. in my opinion, processing to address your questions is the real trick to comet images. Just to clarify, other than polar alignment, this is straight unguided imaging using standard sidereal tracking. Had I thought about it some more, i probably would have done custom comet tracking, but I intended this to be a test shoot. it ended up as my final shoot, due to clouds and lack of more time :( I fully calibrated the frames (unusual for me using a DSLR, but darks, flats, and flat darks were all necessary).? then I used comet alignment to first align everything to the comet. the result was comet only, only dim trailing stars (tweaking rejection here was important) then i used comet alignment a second time, but aligned on the stars, so they were pinpoint. Most of the comet was rejected, save for some brighter overlapping parts I had to manually minimize then I combined the two layers and there you have it :) On Mon, Jul 27, 2020 at 1:34 PM Henk Aling <haling@...> wrote: That's the best image I have seen so far Brian.? I have not seen another image with the wavy details in the tail. --
Brian? Brian Valente portfolio |
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haha funny you mention that - i looked at Roland's picture, and i thought "dang! there's a lot more detail in there than i thought!"? and went back to re-process i really liked Roland's pic.? On Wed, Jul 29, 2020 at 9:24 AM Astronut <hg2u@...> wrote: Hi Brian,? --
Brian? Brian Valente portfolio |
¿ªÔÆÌåÓýI am glad someone likes it: I hated it.? Had they bothered to give it a right-angle eyepiece, it might be ok.? But we old people cannot bend our bodies in the shape necessary to use it.? It¡¯s an abomination. ? From: [email protected] <[email protected]> On Behalf Of Brian Valente
Sent: Monday, July 27, 2020 11:10 AM To: [email protected] Subject: [Losmandy_users_io] Apology to the polar alignment scope ? Dear Polar Alignment Scope, ? I am sorry for bad-mouthing you all this time ? My hubris at deep space imaging and use of electronically assisted polar alignment from sharpcap and polemaster etc. had me believe you were outdated and useless for imaging ? Then the Comet Neowise arrived. ? I realized you were the only way i could quickly and accurately polar align in the field, and still have enough time to image the comet.? ? ?? ? So please, Polar Alignment Scope, accept my apology. I realize that even in this age of computers, you can still play an important role for imaging : ? ? :-) ? ? -- Brian? ? ? ? Brian Valente portfolio |
¿ªÔÆÌåÓýLOL Brian,?
Glad to know that I'm not the only one that uses it. At first I did not like the retical but I have learned to over time. Initially I had wished that it was more like the Orions circle on a circle but the Losmandy style reticle I've found is
more accurate.?
HAPPY SKIES AND KEEP LOOKING UP Deric?
Sent from my Galaxy Tab A
-------- Original message --------
From: Mark de Regt <deregt@...>
Date: 7/30/20 3:08 PM (GMT-06:00)
Subject: Re: [Losmandy_users_io] Apology to the polar alignment scope
I am glad someone likes it: I hated it.? Had they bothered to give it a right-angle eyepiece, it might be ok.? But we old people cannot bend our bodies in the shape necessary to use it.? It¡¯s an abomination. ? From: [email protected] <[email protected]>
On Behalf Of Brian Valente ? Dear Polar Alignment Scope, ? I am sorry for bad-mouthing you all this time ? My hubris at deep space imaging and use of electronically assisted polar alignment from sharpcap and polemaster etc. had me believe you were outdated and useless for imaging ? Then the Comet Neowise arrived. ? I realized you were the only way i could quickly and accurately polar align in the field, and still have enough time to image the comet.? ? ?? ? So please, Polar Alignment Scope, accept my apology. I realize that even in this age of computers, you can still play an important role for imaging : ? ? :-) ?
? -- Brian? ? ? ? Brian Valente portfolio |
¿ªÔÆÌåÓýDoing a quick alignment with the polar scope gets me within about 5 arcmin of the pole. ?That works out to a peak drift around 1-1.5 arcsec/minute. ?That would be horrible for some things, but is almost irrelevant for imaging at 400mm FL with 1-2 minute subs.? -Les
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Hi Brian,
I found it funny that the PoleMaster was so amazingly essential to me that I almost sold off all my Losmandy Polar scopes thinking who needs them? But I also came to realize that if I'm not imaging that night why carry the laptop out into the dark with me when I have that optical device already installed in the mount to do the same thing? For a visual observer using the same mount for imaging IME the PoleMaster camera is as essential as a polar scope. I had to own both at the same time to come to that realization, I even updated both of my polar scopes with the reticles to the 2030 version years ago because of the PoleMaster.?? In case you need an updated polar scope reticle for your Losmandy or AP polar scope Astro Hutech was who I bought them from. I am not sure they are still available but they might have more by now.? -- Chip Louie - Chief Daydreamer Imagination Hardware |
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Chip i think you and I have/had a similar experience! i'm very lucky and fortunate i kept my polar scope, mostly out of laziness haha. but now I picked up a LW tripod and hope to do more interesting things in the field On Sat, Aug 1, 2020 at 11:45 AM Chip Louie <chiplouie@...> wrote: Hi Brian, --
Brian? Brian Valente portfolio |
¿ªÔÆÌåÓýAn out-of-date polar scope reticle will work fine for visual use. Even if it¡¯s 40 years out of date, the resulting polar misalignment will cause a drift of only a few arc seconds per minute.???-Les On Aug 1, 2020, at 11:45 AM, Chip Louie <chiplouie@...> wrote:
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you can kind of eyeball the precession too fortunately my reticle is good through 2030 On Sat, Aug 1, 2020 at 11:59 AM Les Niles <les@...> wrote:
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Brian? Brian Valente portfolio |
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Brian,?
We have more common experiences than is allowed here. I just left them in the mounts NOT because I'm lazy but mostly due to inertia. Because - a) they don't get in the way, b) by leaving them there I won't lose them, c) I would need to find the caps, d) I would need to sell or store them and they seemed to be stored just fine already, e) the thought that it may be handy if the lappy fails, I forget the cable etc. See, not lazy!? But as it turned out, being a frequent visual observer made me realize what a good tool it is to have on hand. I mean I can't forget it, it's already in the mount, takes up no space and has a very useful function when using the Gemini or the Nexus DSC but not using the laptop or imaging.?? But seriously though I just think it is funny that we so frequently come to such similar conclusions about Losmandy things.?? -- Chip Louie - Chief Daydreamer Imagination Hardware |
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Les, Brian,
I used to eyeball it but that gave me sort of inconsistent results, stacks on stacks as it were. I was already guesstimating the position to position the reticle based on the constellation lines and positions and by adding yet another layer of estimation I think caused me to get too far from the correct position. It would work mostly but when it didn't I sort of struggled with GOTO accuracy. My reticles were fine but old and I got tired of guessing and finding that I was a poor guesser. So I updated them and problem solved.? Oh, the updated reticles are still available from Hutech Astro down in the OC> Look at the link: .? ? ? -- Chip Louie - Chief Daydreamer Imagination Hardware |
Chip Louie
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