Re: [Utah-astronomy] Daystar and Coronado?
I understand any solarscope can be double stacked assuming you can match the thread and aperture sizes on the objective of SLAS daystar scope. By pre-filtering the light, you can a narrower angstrom bandpass. I have a Coronado double-stack add on filter for the PST 40mm scope. If it matches the SLAS daystar objective, you are welcomed to borrow it. I'll have to measure the thread size and get back to you. I suggest finding and posting the thread and aperture size measurements taken from the daystar scope objective. Someone in the club is likely to have a match. http://www.slas.us/gallery2/main.php?g2_itemId=3298 http://www.optcorp.com/product.aspx?pid=6665 http://www.coronadofilters.com/doublestack/doublestack.html with respect to the performance, I have only preliminarily used the PST in double stack mode. My initial impression was that it significantly increased the ability of telescope to resolve Ha detail on the Sun's disk. It seemed to reduce the small PST's ability to focus in prominence's on the solar limb. After the double stack lens is attached to the scope, by turning the brass dial knob on the lens's body, several offset images of the Sun are seen the in eyepiece. The main solar scope tuning knob, the tuning knob on the double stack, and the offset of the parafocal disk of the objective are then played with until all the multiple solar images "register" with each other. Then the image will have maximum resolved detail. There is considerably more "tweaking" time in using a double stacked scope as compared to a single stack. But my setup is at a low-end price point. Other club members with the "real" $3-$5K double stacked 90mm+ SolarMax and Lundt scopes may have other perspectives to contribute. Regards, Kurt
Hi Kurt, There's a double stack Coronado and the DayStar at SPOC. Maybe next time you're out there for a star party we could see how to fit things together. patrick On 26 Jun 2010, at 17:54, Canopus56 wrote:
I understand any solarscope can be double stacked assuming you can match the thread and aperture sizes on the objective of SLAS daystar scope. By pre-filtering the light, you can a narrower angstrom bandpass.
I have a Coronado double-stack add on filter for the PST 40mm scope. If it matches the SLAS daystar objective, you are welcomed to borrow it. I'll have to measure the thread size and get back to you.
I suggest finding and posting the thread and aperture size measurements taken from the daystar scope objective. Someone in the club is likely to have a match.
http://www.slas.us/gallery2/main.php?g2_itemId=3298 http://www.optcorp.com/product.aspx?pid=6665 http://www.coronadofilters.com/doublestack/doublestack.html
with respect to the performance, I have only preliminarily used the PST in double stack mode. My initial impression was that it significantly increased the ability of telescope to resolve Ha detail on the Sun's disk. It seemed to reduce the small PST's ability to focus in prominence's on the solar limb.
After the double stack lens is attached to the scope, by turning the brass dial knob on the lens's body, several offset images of the Sun are seen the in eyepiece. The main solar scope tuning knob, the tuning knob on the double stack, and the offset of the parafocal disk of the objective are then played with until all the multiple solar images "register" with each other. Then the image will have maximum resolved detail. There is considerably more "tweaking" time in using a double stacked scope as compared to a single stack. But my setup is at a low-end price point. Other club members with the "real" $3-$5K double stacked 90mm+ SolarMax and Lundt scopes may have other perspectives to contribute.
Regards, Kurt
IS there a source that says you can use the PST filter with the DayStar?
The DayStar is .5 A bandpass which is what PST claims the double stack achieves. I do doubt that it can be threaded on. It is supposed to be attached to the objective lens? I can say that the 50mm objective that SLAS has used with the Daystar has no way to attach anything to the objective. Hi Kurt,
There's a double stack Coronado and the DayStar at SPOC. Maybe next time you're out there for a star party we could see how to fit things together.
patrick
On 26 Jun 2010, at 17:54, Canopus56 wrote:
I understand any solarscope can be double stacked assuming you can match the thread and aperture sizes on the objective of SLAS daystar scope. By pre-filtering the light, you can a narrower angstrom bandpass.
I have a Coronado double-stack add on filter for the PST 40mm scope. If it matches the SLAS daystar objective, you are welcomed to borrow it. I'll have to measure the thread size and get back to you.
I suggest finding and posting the thread and aperture size measurements taken from the daystar scope objective. Someone in the club is likely to have a match.
http://www.slas.us/gallery2/main.php?g2_itemId=3298 http://www.optcorp.com/product.aspx?pid=6665 http://www.coronadofilters.com/doublestack/doublestack.html
with respect to the performance, I have only preliminarily used the PST in double stack mode. My initial impression was that it significantly increased the ability of telescope to resolve Ha detail on the Sun's disk. It seemed to reduce the small PST's ability to focus in prominence's on the solar limb.
After the double stack lens is attached to the scope, by turning the brass dial knob on the lens's body, several offset images of the Sun are seen the in eyepiece. The main solar scope tuning knob, the tuning knob on the double stack, and the offset of the parafocal disk of the objective are then played with until all the multiple solar images "register" with each other. Then the image will have maximum resolved detail. There is considerably more "tweaking" time in using a double stacked scope as compared to a single stack. But my setup is at a low-end price point. Other club members with the "real" $3-$5K double stacked 90mm+ SolarMax and Lundt scopes may have other perspectives to contribute.
Regards, Kurt
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The PST is very sensitive to magnification as well as eyepiece quality. Prominences can disappear entirely if the magnification is pushed too high, or a low-contrast eyepiece is used. This is independant of etalon tuning. Go a little lower in power than you normally would if the prominences seem a bit "iffy", and don't be hesitant to try different eyepieces. On 6/26/10, Canopus56 <canopus56@yahoo.com> wrote:
It seemed to reduce the small PST's ability to focus in prominence's on the solar limb.
According to Daystar the best optical system for their filter is one that does not require use of the red rejection filter, this comes directly from the DayStar people. They sell the rejection filter to protect optical assemblies that would be harmed by the sun.
I have found nothing on the internet the that suggests putting a coronado filter over the objective will improve solar viewing. Or any other H-Alpha filter system other than double stacking the coronado. They are different animals, for instance you do not lose detail with higher magnification provided seeing conditions allow it, with the Daystar. Erik The PST is very sensitive to magnification as well as eyepiece
quality. Prominences can disappear entirely if the magnification is pushed too high, or a low-contrast eyepiece is used. This is independant of etalon tuning.
Go a little lower in power than you normally would if the prominences seem a bit "iffy", and don't be hesitant to try different eyepieces.
On 6/26/10, Canopus56 <canopus56@yahoo.com> wrote:
It seemed to reduce the small PST's ability to focus in prominence's on the solar limb.
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Erik, the magnification limitation with the PST is due solely to aperture. It's only a 40mm objective. On 6/28/10, erikhansen@thebluezone.net <erikhansen@thebluezone.net> wrote:
I have found nothing on the internet the that suggests putting a coronado filter over the objective will improve solar viewing. Or any other H-Alpha filter system other than double stacking the coronado. They are different animals, for instance you do not lose detail with higher magnification provided seeing conditions allow it, with the Daystar.
I guess I misunderstood what you said. I have always found the best magnification to be one that you get the entire solar disk in the field.
I m still trying to figure out where the idea of combining the Coronado and DayStar improves the Daystar comes from though. What is the aperture of the rejection filter used on the Andy? Erik, the magnification limitation with the PST is due solely to
aperture. It's only a 40mm objective.
On 6/28/10, erikhansen@thebluezone.net <erikhansen@thebluezone.net> wrote:
I have found nothing on the internet the that suggests putting a coronado filter over the objective will improve solar viewing. Or any other H-Alpha filter system other than double stacking the coronado. They are different animals, for instance you do not lose detail with higher magnification provided seeing conditions allow it, with the Daystar.
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Actually, with the PST, the visibility of prominences can be increased noticeably if you lower the magnification and settle for a smaller solar disk. You are spreading the light of the prominence out over a smaller area, so contrast is increased. I have had good results with eyepieces of up to 32mm focal length in my PST. The solar disk is very small, and smallish surface details are lost, but the resulting contrast gains are amazing. On 6/28/10, erikhansen@thebluezone.net <erikhansen@thebluezone.net> wrote:
I guess I misunderstood what you said. I have always found the best magnification to be one that you get the entire solar disk in the field.
On 28 Jun 2010, at 16:09, erikhansen@thebluezone.net wrote:
I m still trying to figure out where the idea of combining the Coronado and DayStar improves the Daystar comes from though.
The current S&T mentioned it.
What is the aperture of the rejection filter used on the Andy?
I don't remember exactly but it seems like it's about 100mm or so. Cheers, patrick
I should rig up an off-axis cover so it can be used on the Ealing, too. On 6/28/10, Patrick Wiggins <paw@wirelessbeehive.com> wrote:
On 28 Jun 2010, at 16:09, erikhansen@thebluezone.net wrote:
I m still trying to figure out where the idea of combining the Coronado and DayStar improves the Daystar comes from though.
The current S&T mentioned it.
What is the aperture of the rejection filter used on the Andy?
I don't remember exactly but it seems like it's about 100mm or so.
Cheers,
patrick
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So, the article says it does improve performance? Who wrote it?
the 100mm makes it f30?
On 28 Jun 2010, at 16:09, erikhansen@thebluezone.net wrote:
I m still trying to figure out where the idea of combining the Coronado and DayStar improves the Daystar comes from though.
The current S&T mentioned it.
What is the aperture of the rejection filter used on the Andy?
I don't remember exactly but it seems like it's about 100mm or so.
Cheers,
patrick
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So, the article says it does improve performance? Who wrote it?
I'm not home so I don't have the magazine handy. Look towards the rear of the magazine in the images area. I think it's the only H-Alpha image of the Sun (not an article, rather it's an image with the caption describing the stack). patrick
participants (5)
-
Canopus56 -
Chuck Hards -
erikhansen＠thebluezone.net -
Patrick Wiggins -
paw＠wirelessbeehive.com