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Colored doubles?

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#1 James Cunningham

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Posted 21 September 2012 - 06:39 AM

Can you actually see the colors in colored doubles? Which doubles actually show their colors through the eyepiece? Thanks.
Jim

#2 fvandrog

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Posted 21 September 2012 - 08:44 AM

Can you actually see the colors in colored doubles? Which doubles actually show their colors through the eyepiece? Thanks.
Jim


Yesterday someone posted this link with a very convenient list of interestingly colored double stars. I have immediately bookmarked that link, but have evidently forgotten to who the credit is due.....

F.

#3 James Cunningham

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Posted 21 September 2012 - 08:48 AM

Yes, I saw the link and slewed to a number of them but could not see any colors.

#4 JIMZ7

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Posted 21 September 2012 - 09:04 AM

Can you see colors in Albireo ? It has the Univeristy of Michigan colors of maze & blue. I have a friend who said that he never saw colors in stars until I showed him Albireo. That colored double even looks nice out of focus!

Jim

#5 jimarshall

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Posted 21 September 2012 - 10:10 AM

Can you see colors in Albireo ? It has the Univeristy of Michigan colors of maze & blue. I have a friend who said that he never saw colors in stars until I showed him Albireo. That colored double even looks nice out of focus!

Jim

I agree, Albireo looks spectacular slightly out of focus under moonlit skies. If you can't see color in the stars then, you must have color vision problems.

#6 simpleisbetter

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Posted 21 September 2012 - 10:22 AM

It might be color vision problems, but I tend to suspect Jim Z is right. I remember when I was first starting out and hadn't really developed my viewing skills. I had never noticed or seen color differences in stars, until the first time I looked at Alberio, then the light went off. I could see color on Alberio, many photos showed star color, and the H-R Scale defines it. Therefore, at that moment I realized we can see star color at the eyepiece and began looking for it, now I knew how. My instincts and viewing skills improved at that moment.

#7 drollere

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Posted 21 September 2012 - 10:50 AM

james, there are some simple visual tests available online to test for color vision deficiency: google "ishihara color vision test". while computer monitor presentation is not definitive, they may indicate if there is an issue with your color sensitivity.

i deduce from the number of your posts that you are not unfamiliar with the topic of "star color". but a substantial portion of the "color" in "star color" is analogous to the "music" in "military music": it depends more on your attitude than the objective content. there is emphatic disagreement among visual astronomers as to the "color" of specific stars. that has to do with individual differences in visual capability, and in use of color language.

david knisely has mentioned his short list of well colored double stars, and perhaps he will post it. otherwise, concentrate on single stars of known emphatic color. if you do not see betelgeuse or "herschel's garnet star" or 61 cygni as decidedly yellow or orange, or rigel as decidedly blue, then your visual sensitivity may be a good place to focus your inquiry.

#8 David Knisely

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Posted 22 September 2012 - 12:30 AM

I have seen all of the following double stars, so I can vouch for their colorful nature:

. . . . . . COMMON DOUBLE STARS WITH SIGNIFICANT COLOR CONTRAST . . . . .
. . . . . . . . . (positions, separations, and position angles for 2000) . . . . . .

LEGEND: R.A. = Right Ascension (2000.0) Dec. = Declination
mag. = apparent visual magnitude sp. = spectral type
Sep. = separation (in arc seconds) P.A. = position angle
********************************************************************

Otto Struve (STT) 254, R.A. 0h 1.3m Dec. +60d 21.3'
Primary: mag. 7.2~ (variable) Sp. C5p, Secondary mag. 8.3, sp. A
Sep. 58" arc, P.A. 90 deg. (optical double)
Colors seen in 10 inch: deep reddish-orange and bluish-white.
(primary is Carbon star WZ Cas, other stars also nearby)

Sturve 3053, R.A. 0h 2.6m Dec. +66d 6.0'
Primary: mag. 5.9, sp. G9III, Secondary mag. 7.3, sp. A1V
Sep. 15.0" arc, P.A. 70 deg.
Colors seen in 10 inch: Yellow and pale bluish.

Eta Cassiopeiae, R.A. 0h 49.10m Dec. +57d 49.0'
Primary: mag. 3.4, sp. G0V, Secondary: mag. 7.5, sp. dM0
Sep. 12.8" arc, P.A. 317 deg. (period: 480 years)
Colors seen in 10 inch: Off-white and faint reddish-orange.

ALMACH (Gamma And.), R.A. 2h 3.90m Dec. +42d 19.8'
Primary: mag. 2.2 sp. K3III, Secondary: mag. 4.8 sp. B8V
Sep. 9.8" arc, P.A. 64 deg. (mag. 6.3 companion of Gamma-B at 0.4" arc,
p.a. 103 deg., closing separation).
Colors seen in 10 inch: Yellow (Gold) and light blue.

6 Triangulae (Struve 227), R.A. 2h 12.37m Dec. +30d. 18.3'
Primary: mag. 4.9, Sp. G5III, Secondary: mag. 6.5, Sp. F6V
Sep. 3.9" arc, P.A. 69 deg.
Colors seen in 9.25" SCT: Yellowish-white and bluish-white.

32 Eridani, R.A. 3h 54.29m Dec. -2d 57.3'
Primary: mag. 4.5, sp. G8III, Secondary: mag. 6.1, sp. A2V
Sep. 6.9" arc, P.A. 348 deg.
Colors seen in 10 inch: Yellow and pale blue.

15 Geminorum, R.A. 6h 27.8m Dec. +20d 47.3'
Primary: mag. 4.6, sp. K0, Secondary: mag. 8.5, sp. G0
Sep. 6.9" arc, P.A. 64 deg.
Colors seen in 10 inch: Yellowish-orange and white.

Psi-5 Aurigae, R.A. 6h 46.75m Dec. +43d 34.6'
Primary: Mag. 5.3 sp. G0V, Secondary: mag. 8.5 sp. M0V
Sep. 31.1" arc, P.A. 38 deg.
Colors seen in 10 inch: Off-white and faint orange.

38 Geminorum (STF 982), R.A. 6h 54.64m Dec. +13d 10.7'
Primary: mag. 4.7, sp. A8/F0V, Secondary: mag. 7.7, sp. G6V
Sep. 7.1" arc, P.A. 144 deg.
Colors seen in 10 inch: White and faint orangish.

h3945 (ADS 5951, CMa), R.A. 7h 16.61m Dec. -23d 18.9'
Primary: mag. 4.8 sp. K4III, Secondary: mag. 6.8, sp. A5
Sep. 26.6" arc, P.A. 55 deg.
Colors seen in 10 inch: Orange and bluish-white.
"The Winter Albireo"

S 548 (ADS 6087, Gem), R.A. 7h 27.7m Dec. +22d 8.0'
Primary: mag. 6.9 sp. K5, Secondary mag. 8.9 sp. ?
Sep. 35.5" arc, P.A. 277 deg.
Colors: Orangish and bluish

Iota Cancri, R.A. 8h 46.70m Dec. +28d 45.6'
Primary: mag. 4.0 sp. G8II, Secondary: mag. 6.6 sp. A3V
Sep. 30.5" arc, P.A. 307 deg.
Colors seen in 10 inch: Light yellow and pale blue.

Tau Leonis, R.A. 11h 27.94m Dec. +2d 51.3'
Primary: mag. 4.9 sp. G8Iab, Secondary: mag. 7.4 sp. G5
Sep. 89.7' arc, P.A. 180 deg.
Colors seen in 10 inch: Yellow and white.
*nice low power pair with double 83 Leonis 20' at P.A. 298 deg.

2 Canum Venaticorum, R.A. 12h 16.13m Dec. +40d 39.6'
Primary: mag. 5.7, sp. M1III, Secondary: mag. 8.7, sp. F7V
Sep. 11.3" arc, P.A. 260 deg (2003).
Colors seen in 10 inch: Yellowish-orange and pale bluish-white.

24 Comae Berenices, R.A. 12h 35.13m Dec. +18d 22.6'
Primary: mag. 5.0 sp. K2III, Secondary: mag. 6.6 sp. A7V
Sep. 20.3" arc, P.A. 271 deg.
Colors seen in 10 inch: Yellow and pale blue.

Cor Caroli (Alpha CVn), R.A. 12h 56.00m Dec. +38d 19.1'
Primary: mag. 2.9 sp. A0spe, Secondary: mag. 5.6, sp. F0V
Sep. 18.8" arc, P.A. 230 deg.
Colors seen in 10 inch: Bluish-white and off-white (cream).

Izar (Epsilon Bootis), R.A. 14h 44.99m Dec. +27d 4.5'
Primary: mag. 2.4 sp. K0II, Secondary: mag. 5.1, sp. A2V
Sep. 2.8" arc P.A. 339 deg.
Colors seen in 10 inch: Yellow and light blue.

Xi Bootis, R.A. 14h 51.39m Dec. +19d 6.0'
Primary: mag. 4.5, sp. G8V, Secondary: mag. 6.8, sp. K5V
Sep. 6.8" arc P.A. 320 deg.
Colors seen in 10 inch: Pale yellowish white and orange.

Antares (Alpha Sco). R.A. 16h 29.41m Dec. -26d 25.9'
Primary: mag. 1.0v sp. M1I, Secondary: mag. 5.4 sp. B4
Sep. 2.6" arc P.A. 274 deg.
Colors seen in 10 inch: Orange and light blue.

Ras Algethi (Alpha Her) R.A. 17h 14.65m Dec. +14d 23.4'
Primary: mag. 3.2v sp. M5II Secondary: mag. 5.4, sp. F2/G3
Sep. 4.6" arc P.A. 104 deg.
Colors seen in 10 inch: Reddish-orange and pale bluish-white.

95 Herculis. R.A. 18h 1.5m Dec. +21 deg. 36'
Primary: mag. 4.9, Sp. A5III, Secondary: Mag. 5.2 sp. G5?
Sep. 6.3" arc P.A. 256 deg.
Colors seen in 10 inch: pale bluish-white and gold.

59 Serpentis, R.A. 18h 27.2m Dec. +0d 45.9'
Primary: mag. 5.2, Sp. GOIII, Secondary: mag. 7.4, sp. ?
Sep. 3.9" arc P.A. 320 deg.
Colors seen in 10 inch: Yellowish-white and pale bluish-white

Omicron Draconis, R.A. 18h 51.20m Dec. +59d 23.3'
Primary: mag. 4.6, Sp. G9III, Secondary: mag. 8.1, sp. K3III
Sep. 36.5" arc P.A. 319 deg.
Colors seen in 10 inch: Yellow and faint orangish

SHJ 282 (O. Struve 525), Lyra), R.A. 18h 54.90m Dec. +33d 58.0'
Primary: mag. 6.1, sp. G8III Secondary(s): mag. 9.1, sp. A8
B component Sep. 1.8" arc, P.A.188 deg . (O. Str 525)
C component: mag. 7.7 Sp. A1, Sep. 45.4" arc P.A. 350 deg.
Colors seen in 10 inch: Yellowish-white and bluish-white.

Albireo (Beta Cyg) 19h 30.72m Dec. +27d 57.6'
Primary: mag. 3.1 sp. K3II Secondary: mag. 5.1 sp. B8V
Sep. 34.3" arc P.A. 54 deg.
Colors seen in 10 inch: Yellow and light blue.

ADS 12900 (Cyg). 19h 45.86m Dec. +35d 0.77'
Primary: mag. 6.1 sp. K2? Secondary: mag. 8.6 sp. A2V
Sep. 37.5" arc P.A. 25 deg.
Colors seen in 10 inch: Yellow and blue.

Gamma Delphini, R.A. 20h 46.73m Dec. +16 deg. 7.8'
Primary: mag. 4.4 sp. K1IV, Secondary: mag. 5.0 sp. F7V.
Sep. 9.6" arc P.A. 268 deg.
Colors seen in 10 inch: Yellowish and white (hint of blue)?

12 Aquari, R.A. 21h 4.1m Dec. -5 deg. 49'
Primary: mag. 5.8 sp. G4III, Secondary: mag. 7.5 sp.?
Sep. 2.5" arc P.A. 196 deg. (2003)
Colors seen in 10 inch: Yellowish-white and pale bluish-white.

Delta Cephei R.A. 22h 29.20m Dec. +58d 25'
Prmary: mag. 4.07 (variable) sp. F5-G3 Secondary: mag. 6.27 sp. B7
Sep. 40.8" arc P.A. 191 deg.
Colors seen in 10 inch: Yellowish-white and light blue.

Clear skies to you.

#9 James Cunningham

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Posted 22 September 2012 - 06:04 AM

Thank you so much.
Jim

#10 azure1961p

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Posted 22 September 2012 - 12:30 PM

Hi Jim,

Color is one of those finesse aspects in observation where it takes some skill that grows over time. Still there are obvious ones and Dave Knisley makes a nice list of it.

Pete

#11 JIMZ7

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Posted 22 September 2012 - 12:40 PM

David thanks for the very nice selection of "significant colored stars"!

Jim :refractor:

#12 drollere

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Posted 22 September 2012 - 01:14 PM

one merit worth emulating in knisely's list is his analytic color language. it consists of basic hue terms (red, orange, yellow, green, blue, violet, white), plus modifying blends (blue white, yellow orange, etc.), plus the tint designators "ish" (yellowish orange), plus the saturation designator "pale". star colors are rarely strongly saturated, excepting perhaps carbon stars, but "intense" is a high saturation term to keep handy.

applied consistently and carefully, the terms allow meaningful comparisons between stars and accurate recall of what the stars looked like. i believe william herschel was the first astronomer to routinely describe double star color, and his descriptions are similarly restrictive and analytical.

the only confusion i encounter is whether "faint" means dim or weakly colored; "gold" or "copper" are not really helpful to compare one color with another but are evocative anyway. "bright" or "dim" are good to apply when brightness affects the quality of the color.

this is in stark contrast to the 19th century fashion, which ranges from precious stone effusions (topaz, emerald, sapphire, garnet, ruby, diamond, etc., etc.) to wallpaint nomenclature (lavender, chartreuse, maroon, cerulean, etc.). haas breaks new ground by advancing poetry into the culinary arts, with "grapefruit orange," "pumpkin orange," "citrus orange," "eggshell white," etc., along with "silvery gray" and other pointless overinterpretations. how is citrus orange different from grapefruit orange? sissy is the only person who knows for sure, and a few years from now she may not even remember what was meant by the difference.

#13 simpleisbetter

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Posted 22 September 2012 - 02:17 PM

I might agree with the gold and copper, it's somewhat a personal interpretation. I take it to mean both colors represent various tints between yellow and orange, with gold being more yellow and copper more orange. Maybe I'm wrong?

I find Haas color descriptions quite difficult to understand at times. David's system I find far better overall.

#14 azure1961p

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Posted 22 September 2012 - 05:38 PM

and other pointless overinterpretations. how is citrus orange different from grapefruit orange? sissy is the only person who knows for sure, and a few years from now she may not even remember what was meant by the difference.


I think that's the peril in striking out for individual expression and distinction.

Oddly I have noted a citrus yellow tone, independent of Hass's ditherings. Thanks for the laugh - especially at the close of a long day. Perhaps she would like to be known as Admiral Haas (Smyth).

All in fun,

Pete

#15 Tom and Beth

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Posted 22 September 2012 - 07:49 PM

I might agree with the gold and copper, it's somewhat a personal interpretation. I take it to mean both colors represent various tints between yellow and orange, with gold being more yellow and copper more orange. Maybe I'm wrong?

I find Haas color descriptions quite difficult to understand at times. David's system I find far better overall.


It is possibly explained if you consider that Females have a different proportion of Cones to Rods then men, as well as Age deterioration of our Cornea.

Not wishing to get this thread on a tangent, but next time you are sharing your Telescope with the public, purposely choose a few Colored pairs and note the difference you get in their descriptions.

#16 Tom and Beth

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Posted 22 September 2012 - 07:55 PM

Can you actually see the colors in colored doubles? Which doubles actually show their colors through the eyepiece? Thanks.
Jim


Jim,

Quickly going through the thread, I might have missed what size instrument you are using. Colors may not be strong enough in small scopes (like a 50MM finder) yet washed out in others like a 14 inch scope. I don't have any Science to back it up but have "felt" many bright Colored Stars are best viewed in 4 to 8 inch scopes.

#17 C_Moon

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Posted 22 September 2012 - 09:15 PM

I might agree with the gold and copper, it's somewhat a personal interpretation. I take it to mean both colors represent various tints between yellow and orange, with gold being more yellow and copper more orange. Maybe I'm wrong?

I find Haas color descriptions quite difficult to understand at times. David's system I find far better overall.


It is possibly explained if you consider that Females have a different proportion of Cones to Rods then men, as well as Age deterioration of our Cornea.

Not wishing to get this thread on a tangent, but next time you are sharing your Telescope with the public, purposely choose a few Colored pairs and note the difference you get in their descriptions.


I've had the occasion more than once of showing Albierio at outreach events, asking what they say and hearing, "two white stars." :confused:

I'm an engineer by day, so by night I don't mind the non-analytic color classifications. I must say that Sissy's "unique" color descriptions have motivated me on more than one night to hunt down an otherwise obscure (i.e., non-famous) double just to see what "pale topaz with a lilac tint" was all about. :ubetcha:

#18 simpleisbetter

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Posted 22 September 2012 - 10:51 PM

I might agree with the gold and copper, it's somewhat a personal interpretation. I take it to mean both colors represent various tints between yellow and orange, with gold being more yellow and copper more orange. Maybe I'm wrong?

I find Haas color descriptions quite difficult to understand at times. David's system I find far better overall.


It is possibly explained if you consider that Females have a different proportion of Cones to Rods then men, as well as Age deterioration of our Cornea.

Not wishing to get this thread on a tangent, but next time you are sharing your Telescope with the public, purposely choose a few Colored pairs and note the difference you get in their descriptions.


True, and it could be the case. But to me it comes down to the way colors are described. Men see, for example, a rose colored fabric, as rose. Women see, dusty rose, misty rose, off-pink rose, who knows rose... And they seem to know colors much more, perhaps a lifestyle difference as far as what is important or significant to each. That's more where I was coming from.

For all the women reading here, please forgive me I'm not trying to sound bigoted, so if my Archie Bunker genes are showing through, sorry. But it's just a fact that I've encountered many times over the years, as well as many of my friends and coworkers.

#19 Rich (RLTYS)

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Posted 23 September 2012 - 06:44 AM

this is in stark contrast to the 19th century fashion, which ranges from precious stone effusions (topaz, emerald, sapphire, garnet, ruby, diamond, etc., etc.) to wallpaint nomenclature (lavender, chartreuse, maroon, cerulean, etc.). haas breaks new ground by advancing poetry into the culinary arts, with "grapefruit orange," "pumpkin orange," "citrus orange," "eggshell white," etc., along with "silvery gray" and other pointless overinterpretations. how is citrus orange different from grapefruit orange? sissy is the only person who knows for sure, and a few years from now she may not even remember what was meant by the difference.


Personally I don't agree that these color descriptions are useless. It was descriptions like these that got me interested in double star observing. They have a beautiful quality about them.

Rich (RLTYS)

#20 azure1961p

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Posted 23 September 2012 - 12:13 PM

On balance it's more engaging to read these comparitive color descriptions than merely calling a star G2 or F or M. With regard to the way women see color or rather describe it, I'd be far more enclined to believe it's more about sensitivity of observation and interpretation than results brought about by differences in retinal layout. Men can seem fairly ham fisted in describing color. It's an interpretation issue not so
much a retinal response.

My thoughts on it anyway.

Pete

#21 rookie

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Posted 23 September 2012 - 07:36 PM

From my female perpective, I think I'm more prosaic about my own observations in regards to describing one rose hue from another, but I do love reading unique descriptions and often use them to see if I can discern an author's perception.

I do see single star, Zubeneschamali as greenish. :ubetcha:

#22 Aleko

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Posted 23 September 2012 - 09:56 PM

If the aperture of the scope makes the stars of a double appear too bright, the colors wash out. Throwing the image a bit out of focus often times brings out the color. One can also change the magnification to find the best saturation of color.

Alex

#23 RobDob

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Posted 23 September 2012 - 10:36 PM

Can you see colors in Albireo ? It has the Univeristy of Michigan colors of maze & blue. I have a friend who said that he never saw colors in stars until I showed him Albireo. That colored double even looks nice out of focus!

Jim

I agree, Albireo looks spectacular slightly out of focus under moonlit skies. If you can't see color in the stars then, you must have color vision problems.


I was out last night taking point'n'shoot pics of the Lunar X and grabbed a batch of Albireo shots. None were in focus, no way to hold the camera that steady!

Found this blurry shot that really depicts the colors spot on! Z12 w/28mm RKE and Nikon S6300 afocal through the eyepiece.

Rob

Attached Files



#24 brianb11213

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Posted 24 September 2012 - 02:58 AM

If the aperture of the scope makes the stars of a double appear too bright, the colors wash out. Throwing the image a bit out of focus often times brings out the color. One can also change the magnification to find the best saturation of color.

+1 ... great advice. Viewing brighter doubles in strong moonlight or twilight (when it's too bright for other DSOs) also makes a lot of sense.

#25 rookie

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Posted 24 September 2012 - 06:48 AM

Rob, I agree, hand holding a camera at the lens really is impossible. You can buy a universal afocus camera adapter. I have one that fits both 1" & 2" ep's. It is not big enough for my wide field 2" pieces, but it does a great job with the others. My Cannon S100 lens fits perfectly in the Nagler & panoptic 1 1/2" ep's without touching the glass. You make best focus with your eye and let the camera do the rest.






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