Tube interior blackening and baffling

Discuss your refractor type scopes here.
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Re: Tube interior blackening and baffling

#21

Post by Lady Fraktor » Thu Sep 26, 2019 7:48 pm

I have not really mastered the "run away" technique yet... :lol:
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Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
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#22

Post by notFritzArgelander » Thu Sep 26, 2019 8:16 pm

Bigzmey wrote:
Thu Sep 26, 2019 7:31 pm
notFritzArgelander wrote:
Thu Sep 26, 2019 7:29 pm
Lady Fraktor wrote:
Thu Sep 26, 2019 7:22 pm
Well I am not in the mood for a bar fight before bed, I have been banned from CN before :lol:

Maybe I will post the question over there in the morning and see how long it takes a mob to form!
Just be sure that when you see the torchlights and pitchforks get out! I never learned that lesson..... ;)
What do you mean? This when the fun begins. :D
I think you're more extroverted than I. ;) While I'm perfectly happy to engage in a one-on-one death match with an abusive troll, I shy away from lynch mobs! :lol:
Scopes: Refractors: Orion ST80, SV ED80 A f7; Newtonians: Z12 f5; Catadioptrics: VMC110L, Intes MK66. EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker III, Vixen Porta II, Celestron CG5, Orion Sirius EQG
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#23

Post by man1 » Fri Sep 27, 2019 7:18 pm

Lady Fraktor wrote:
Thu Sep 26, 2019 5:01 pm
After reading the postings of most of the membership for the last three years I find it hard to believe there are only 2 other people with opinions on the original topic :lol:

Hey... some of us are just reading along and learning..... http://www.bbastrodesigns.com/baffle.html
http://www.berfield.com/baffles.html

Reading your posts on this topic made me curious and now I even started to look and learn more about it!

Cheers...
Orion XT10i custom, Orion GiantView BT-70, Bushnell Natureview 20-60x65
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#24

Post by man1 » Fri Sep 27, 2019 7:21 pm

notFritzArgelander wrote:
Wed Sep 25, 2019 7:09 pm
I think that color still matters. Sure if you are at a truly dark site you can get away with practically anything. But if you have a neighbor that flips on a porch light the incoming light is going to be at an odd angle that baffling might not defeat. Flat black is baffling's backup. Defend in depth and don't skimp I think.

Assembling a satellite in a clean room is one environment. Having to deal with random lights impinging on the objective from wacky angles... is different.
I think you are right, color would still matter it also depends on the wavelength.

Cheers...
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#25

Post by Lady Fraktor » Fri Sep 27, 2019 9:05 pm

Here is a modification of the Berfield method which adds one or two more baffles if you want.
Berfield on bottom, modification on top.
Berfield mod by Nils Olof Carlin.jpg
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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#26

Post by man1 » Fri Sep 27, 2019 9:35 pm

Lady Fraktor wrote:
Fri Sep 27, 2019 9:05 pm
Here is a modification of the Berfield method which adds one or two more baffles if you want.
Berfield on bottom, modification on top.
Berfield mod by Nils Olof Carlin.jpg
Interesting design ideas, a few weeks ago when I was looking around for flocking ideas for my new XT10i, I came across one picture of a newtonian type scope and it had baffles spaced at about every 3 inches. I was surprised, but again I'm not an expert at this.

In your Berfield picture, I would say the Berfield mod (the top version) would be my choice. Simply by looking at the angles of reflections. The more I think about it, I think a conical dew shield would do the same trick, same idea as you would see on a lelephoto lens in photography. A bit harder to implement on a telescope, because it would have to be aligned and not just for dew prevention (just slipped on any old way).

What do you think?

Cheers....
Orion XT10i custom, Orion GiantView BT-70, Bushnell Natureview 20-60x65
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#27

Post by notFritzArgelander » Fri Sep 27, 2019 10:20 pm

man1 wrote:
Fri Sep 27, 2019 9:35 pm
Lady Fraktor wrote:
Fri Sep 27, 2019 9:05 pm
Here is a modification of the Berfield method which adds one or two more baffles if you want.
Berfield on bottom, modification on top.
Berfield mod by Nils Olof Carlin.jpg
Interesting design ideas, a few weeks ago when I was looking around for flocking ideas for my new XT10i, I came across one picture of a newtonian type scope and it had baffles spaced at about every 3 inches. I was surprised, but again I'm not an expert at this.
Newtonians benefit from baffling. It adds to the cost which is why it's often done after market. I'm considering this OTA which has an excellent and unusual baffling design involving a non cylindrical tube.

http://www.kasai-trading.jp/nero200e.html

The third small picture on the right shows a light trapping out-dent opposite the focuser which I REALLY like.
In your Berfield picture, I would say the Berfield mod (the top version) would be my choice.
I agree I prefer the top version.
Scopes: Refractors: Orion ST80, SV ED80 A f7; Newtonians: Z12 f5; Catadioptrics: VMC110L, Intes MK66. EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker III, Vixen Porta II, Celestron CG5, Orion Sirius EQG
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#28

Post by man1 » Sat Sep 28, 2019 2:40 am

notFritzArgelander wrote:
Fri Sep 27, 2019 10:20 pm
man1 wrote:
Fri Sep 27, 2019 9:35 pm
Lady Fraktor wrote:
Fri Sep 27, 2019 9:05 pm
Here is a modification of the Berfield method which adds one or two more baffles if you want.
Berfield on bottom, modification on top.
Berfield mod by Nils Olof Carlin.jpg
Interesting design ideas, a few weeks ago when I was looking around for flocking ideas for my new XT10i, I came across one picture of a newtonian type scope and it had baffles spaced at about every 3 inches. I was surprised, but again I'm not an expert at this.
Newtonians benefit from baffling. It adds to the cost which is why it's often done after market. I'm considering this OTA which has an excellent and unusual baffling design involving a non cylindrical tube.

http://www.kasai-trading.jp/nero200e.html

The third small picture on the right shows a light trapping out-dent opposite the focuser which I REALLY like.
In your Berfield picture, I would say the Berfield mod (the top version) would be my choice.
I agree I prefer the top version.
That Nero-200N looks pretty amazing, I bet it is a high performance telescope. I do like the out-dent feature as well, that makes a lot of sense!
I think the clean-out door at the primary mirror will come in handy to cool things down rather quickly. That's a nice telescope!

Cheers...
Orion XT10i custom, Orion GiantView BT-70, Bushnell Natureview 20-60x65
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#29

Post by Lady Fraktor » Sat Sep 28, 2019 4:17 am

TThe "cone" does not need to be extreme.
The dewshield I made is 380mm long but is only 3mm wider at the end.
It really depends on the telescope you are putting it on, you can slide a ruler forward along the tube until you see it in view and then pull it back a bit and that is the maximum length you make it.
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Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
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#30

Post by Lady Fraktor » Sat Sep 28, 2019 4:33 am

The Kasai has some interesting features, I wonder if the fibreglass tube will eliminate dewing as well as Kruppux does?
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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#31

Post by notFritzArgelander » Sat Sep 28, 2019 5:52 am

Lady Fraktor wrote:
Sat Sep 28, 2019 4:33 am
The Kasai has some interesting features, I wonder if the fibreglass tube will eliminate dewing as well as Kruppux does?
I don't know that material.
Scopes: Refractors: Orion ST80, SV ED80 A f7; Newtonians: Z12 f5; Catadioptrics: VMC110L, Intes MK66. EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker III, Vixen Porta II, Celestron CG5, Orion Sirius EQG
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#32

Post by Lady Fraktor » Sat Sep 28, 2019 6:05 am

It is a fibreglass resin impregnated paper then rolled.
It is apparently quite resistant to temperature changes and rarely forms dew on it. It is also quite strong.
APM Telescope has been making tubes from it for quite a few years now and I think there may be one or two other places as well.
You may see it called Kruppux 50
68845494_RLG6L2B2_phenolic1.jpg
68845498_5XLtbVcA_phenolic2.jpg
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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#33

Post by notFritzArgelander » Sat Sep 28, 2019 6:08 am

Lightweight and high specific heat capacity sounds good to me!
Scopes: Refractors: Orion ST80, SV ED80 A f7; Newtonians: Z12 f5; Catadioptrics: VMC110L, Intes MK66. EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker III, Vixen Porta II, Celestron CG5, Orion Sirius EQG
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#34

Post by Lady Fraktor » Sat Sep 28, 2019 3:44 pm

Now going back to the original topic,
If a refractor has a properly made dewshield (2.5-3x objective diameter long) with baffling to stop off axis light and the tube is properly baffled as well is there anything else that can be done?
What do you think would be proper spacing of the dewshield baffles?
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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#35

Post by notFritzArgelander » Sat Sep 28, 2019 7:25 pm

Lady Fraktor wrote:
Sat Sep 28, 2019 3:44 pm
Now going back to the original topic,
If a refractor has a properly made dewshield (2.5-3x objective diameter long) with baffling to stop off axis light and the tube is properly baffled as well is there anything else that can be done?
No I think that should be complete.
What do you think would be proper spacing of the dewshield baffles?
How many baffles do you want to make? The main requirement for me would be assurance that the objective not be shadowed in the TFOV. So a series of annuli with varying inner clear diameter opening around a cone with an angle of the maximum TFOV would do. The minimum would be one annulus at the sky end of the dew shield. something like 3-5 spaced evenly or (my preference) more closely near the objective. Check with the Berfield procedure.
Scopes: Refractors: Orion ST80, SV ED80 A f7; Newtonians: Z12 f5; Catadioptrics: VMC110L, Intes MK66. EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker III, Vixen Porta II, Celestron CG5, Orion Sirius EQG
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#36

Post by Lady Fraktor » Sat Sep 28, 2019 8:27 pm

My thinking was possibly 3-5 starting halfway down the shield in front of the objective.
I have the light cone drawn out already from placing the tube baffles ( and checking shield length) so just a matter having some time to make them now.
Thank you for the thoughts nFA :)
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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#37

Post by notFritzArgelander » Sat Sep 28, 2019 8:32 pm

PS I just skimmed some topics over at "the other place" and saw a remarkable statement: "any baffling in the dewshield will vignette the objective" or some such. If you space the baffling so there is a widening cone toward the sky with a vertex angle at or slightly exceeding the TFOV of the scope (accounting for the focuser) I don't see how this is true.

Another comment was that a baffled dewshield would cause poor seeing due to currents in the dew shield. I can't buy that either as long as it isn't excessive.

If someone would correct me on these points it would be nice, if indeed I misunderstand.
Scopes: Refractors: Orion ST80, SV ED80 A f7; Newtonians: Z12 f5; Catadioptrics: VMC110L, Intes MK66. EPs: KK Fujiyama Orthoscopics, 2x Vixen NPLs (40-6mm) and BCOs, Baader Mark IV zooms, TV Panoptics, Delos, Plossl 32-8mm. Mixed brand Masuyama/Astroplans Binoculars: Nikon Aculon 10x50, Celestron 15x70, Baader Maxbright. Mounts: Star Seeker III, Vixen Porta II, Celestron CG5, Orion Sirius EQG
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#38

Post by Lady Fraktor » Sat Sep 28, 2019 8:41 pm

I think I read the same thread yesterday and like you find it a bit hard to be convinced if it is done properly.
Since one of the jobs of a shield is to hold a spot of steady air in front of the lens to help prevent fogging of the lens I cannot see how it would cause excessive tube currents as that poster stated.
If that was the case a dewshield on a SCT or Mak should render them completely useless.
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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#39

Post by John Baars » Sun Sep 29, 2019 12:03 pm

I have constructed several ATM refractors. When the interior was still unpainted, the daylight views were horrible. One big misty blur. No matter what color. I didn't try it out on stars though. Mat-black paint made it far more better. Baffling the inside with mat-black baffles did the finishing touch. One has to calculate or draw (1:1 scale, preferably) the number and placement of the baffles though. Sort of ray-tracing on paper. I think most of us know this: http://www.berfield.com/baffles.html
By increasing the diameter of the tube, the number of baffles needed rapidly goes down. It seems like creating a "gigantic darkroom" behind the baffle in which false and incident light is muted. The same "darkrooms" are created in ray-traced eyepieces like the Pentax XO5 and the newest Vixens HR. I think most of us know this too.
I think damping of incoming incident light is more important than the color of the inside tube. From the eyepieces point of view it is best not to see the walls of the tube anywhere. Dark well placed baffles will take care of that. From the lenses point of view everything is okay as long there are no strongly reflective spots, which can be reflected to the lens and then back to the eyepiece.

Long time ago my old master-builder said to me: "John, when you look down a telescope from the eyepiece point of view the only thing you want to see is your objective surrounded by complete darkness. Anything else is wrong."

I suppose this is common knowledge for us, but not for all manufacturers.

Which remembers me of painting the inside walls of the "darkrooms in my refractor" nice and green (510-550 Nanometers) one of these days:-) It may attract more fotons coming in:-)
Telescopes in Schiedam : SW 150mm F/5 Achromat, SW Evostar 120ED F/7.5, Vixen 102ED F/9, OMC140 maksutov F/14.3, SW 102MAK F/13 on Vixen GPDX.
Eyepieces: Kitakaru, Eudiascopic, Jena, Panoptic, Nagler, Morpheus, Leica ASPH, Brandon, Parks, Fujiyama, Pentax XO.
Binoculars: AusJena 10X50 Jenoptem, Swarovski Habicht 7X42, Celestron Skymaster 15X70, Swift Observation 20X80.

Astronomical Rijswijk observatory telescopes: Astro-Physics Starfire 130 f/8 on NEQ6, 6 inch Newton on GP, C8 on NEQ6, Meade 14 inch SCT on EQ8, Lunt.

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#40

Post by Lady Fraktor » Sun Sep 29, 2019 4:47 pm

It would be an interesting experiment if you paint it green John :)
Here are a couple of images, one showing my awesome MS Paint skills :D and of course nothing on it is to scale. It just shows what I am thinking of doing with the dewshield.
The other is how the tube interior is currently a bright surrounding.
Dewshield baffles.jpg
Tube Interior.png
🇸🇰
Proper Telescopes: Antares 105 f/15, Celestron 150 f/8, Stellarvue NHNGDX 80 f/6.9, TAL 100RS f/10, TS 102 f/11, UR 70 f/10, Vixen ED115s f/7.7
Mounts: Celestron AS-GT, Celestron CG-5 w/ Argo Navis & tracking motor, SLT w/ pier & tripod mods, Manfrotto 028b w/ SV M2C, Mantrotto 055Pro w/ 128RC, TAL MT1C, Vixen SXP w/ HAL-130 & half pier
Diagonal: 2" A-P Maxbright, 2" Baader Herschel Wedge (P), 2" Zeiss/ Baader Amici Prism (DX2), 2" Orion Amici Prism, 2" Stellarvue DX, 2" TeleVue EverBrite
Eyepieces: Antares to Zeiss
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