Blackening lens edges

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John Baars Netherlands
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Blackening lens edges

#1

Post by John Baars »


Should lens edges be blackened or not? I know, this discussion is being conducted to the highest echelons of the very best brands.

An amateur with the same telescope as me (the 150 f / 5 refractor) told me he saw a difference. (I like to believe that since he is a solar photographer)

If it doesn't help on Deepsky, it won't do any harm. So I applied a layer of black with a felt-tip pen. No paint on purpose due to the already limited space of the lens in the cell.

Attached three photos. One before, after and during the process.
IMG_1748 (510x680).jpg
IMG_1755 (510x680).jpg
IMG_1753 (510x680).jpg
Well, what do you think? Should lens-edges be blackened or not?
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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Re: Blackening lens edges

#2

Post by DeanD »


Hi John,

Looks interesting: the second image certainly would indicte that there is likely to be less scattered light. I'll be interested in your viewing experience: whether you can notice a difference.

Let us know how you go,

All the best,

Dean
Telescopes: 12" f5 dob, Celestron CPC800, 150mmf5 Celestron achro, Tak TSA102, TV76, ETX125...
Binos: Steiner Wildlife XP 10x26, Swarovski 8x30 Habicht, Zeiss SFL 8x40, Vanguard Endeavour 10.5x45, Fuji FMTR-SX 10x50, Tak 22x60, Orion Resolux 15x70
Eyepieces: way too many (is that possible?), but I do like my TV 32mm plossl, 13mm Nagler T6, 27mm Panoptic and 3-6mm Nagler zoom, plus Fujiyama 18mm and 25mm orthos and Tak 7.5mm LE
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Re: Blackening lens edges

#3

Post by John Donne »


As you say John...it won't hurt anything...unless you disorient the lens cell.
I know this because I committed this disorientation the first time around. I eventually sorted things out, but it took a bit of frustration and fiddling. 😊
I have since successfully blackened the lens edges of two of my second hand telescopes in the process of other service and rehab.
I have even blackened the edge of the corrector plate in my 10 inch Meade SCT.
I read some discussion on this treatment in other forum and the treatment was thought to be benificial.

Thank you for the thread and images.
SCOPES :ES127 f7.5, SW100 f9 Evostar, ES80 F6, LXD75 8" f10 SCT, 2120 10" f10 SCT, ES152 f6.5.
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Re: Blackening lens edges

#4

Post by notFritzArgelander »


FWIW I firmly believe in blackened lens edges. All of them. Objectives and oculars too.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 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 IV, Vixen Porta II, Celestron CG5
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Re: Blackening lens edges

#5

Post by Bigzmey »


I am 'best the enemy of the good' guy. I try not to take stuff apart to achieve moderate gains for the fear to mess things up.

I also believe, that blackening lens edges and using proper flat black paint or flocking should be done at the factory. I mean how hard it could be? :)
Scopes: Stellarvue: SV102ED; Celestron: 9.25" EdgeHD, 8" SCT, 150ST, Onyx 80ED; iOptron: Hankmeister 6" Mak; SW: 7" Mak; Meade: 80ST.
Mounts: SW: SkyTee2, AzGTi; iOptron: AZMP; ES: Twilight I; Bresser: EXOS2; UA: MicroStar.
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EPs: Pentax: XWs & XFs; TeleVue: Delites, Panoptic & Plossls; ES: 68, 62; Vixen: SLVs; Baader: BCOs, Aspherics, Mark IV.
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Re: Blackening lens edges

#6

Post by notFritzArgelander »


Bigzmey wrote: Thu Oct 29, 2020 2:39 am I am 'best the enemy of the good' guy. I try not to take stuff apart to achieve moderate gains for the fear to mess things up.

I also believe, that blackening lens edges and using proper flat black paint or flocking should be done at the factory. I mean how hard it could be? :)
I agree that it should be done at the factory.
Scopes: Refs: Orion ST80, SV 80EDA f7, TS 102ED f11 Newts: AWB 130mm, f5, Z12 f5; Cats: VMC110L, Intes MK66,VMC200L f9.75 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 IV, Vixen Porta II, Celestron CG5
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Re: Blackening lens edges

#7

Post by Lady Fraktor »


A nice job John, I do all of mine as well though the Stellarvue and Vixen were done in the shop.
I am under the impression that Astro-Physics does not edge blacken the telescope lens.
Would you be able to check this?
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
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Re: Blackening lens edges

#8

Post by John Baars »


DeanD wrote: Thu Oct 29, 2020 1:09 am Hi John,

Looks interesting: the second image certainly would indicte that there is likely to be less scattered light. I'll be interested in your viewing experience: whether you can notice a difference.

Let us know how you go,

All the best,

Dean
Quite sure you will be notified! See my next observation report.

John Donne wrote: Thu Oct 29, 2020 1:29 am As you say John...it won't hurt anything...unless you disorient the lens cell.
I know this because I committed this disorientation the first time around. I eventually sorted things out, but it took a bit of frustration and fiddling. 😊
I have since successfully blackened the lens edges of two of my second hand telescopes in the process of other service and rehab.
I have even blackened the edge of the corrector plate in my 10 inch Meade SCT.
I read some discussion on this treatment in other forum and the treatment was thought to be benificial.

Thank you for the thread and images.
To reassure you: this was certainly not the first time I dissembled a doublet in a lens-cel. Last time it was to minimize axial coma in the same lens. I made all the necessary precautions. :knife:

notFritzArgelander wrote: Thu Oct 29, 2020 1:43 am FWIW I firmly believe in blackened lens edges. All of them. Objectives and oculars too.
The pictures above underline it.

Bigzmey wrote: Thu Oct 29, 2020 2:39 am I am 'best the enemy of the good' guy. I try not to take stuff apart to achieve moderate gains for the fear to mess things up.

I also believe, that blackening lens edges and using proper flat black paint or flocking should be done at the factory. I mean how hard it could be? :)
I believe it should be done at the factory too. But if they haven't, I'll do what is within my skills and knowledge. And this is.

Lady Fraktor wrote: Thu Oct 29, 2020 5:34 am A nice job John, I do all of mine as well though the Stellarvue and Vixen were done in the shop.
I am under the impression that Astro-Physics does not edge blacken the telescope lens.
Would you be able to check this?
Thanks. I'll check the Astro-Physics as soon as I can. Due to Corona regulations I am not regurlarly at the observatory nowadays.
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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Re: Blackening lens edges

#9

Post by Lady Fraktor »


I came across this image the other day of a 203mm f/9 TMB/ LZOS refractor and it appears that the edges were not edge blackened.
It does have a ring directly behind the lens cell that appears to be flocked though.
203LensCell.jpg
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
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Re: Blackening lens edges

#10

Post by Ylem »


More gooder is not always gooder LOL
I think Uncle Rod said something like that 🤣

IMHO, if you know what you are doing, or have other reasons to disassemble, then go for it :)

Otherwise, leave good be ;)
Clear Skies,
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Re: Blackening lens edges

#11

Post by John Baars »


Lady Fraktor wrote: Thu Oct 29, 2020 5:34 am I am under the impression that Astro-Physics does not edge blacken the telescope lens.
Would you be able to check this?
I just checked the 130mm f/8
IMG_1757.JPG
Click to enlarge.

Bit difficult to say, the grey ring seems threaded. I think I count three blackened edges.
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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Re: Blackening lens edges

#12

Post by Thefatkitty »


Hi John, good call on that; I've done the same and noticed a big difference. However, the only scopes I've done this with is my shorter F/L Japanese cemented doublets. In taking apart my Celestron/Vixen and Towa scopes of a longer focal length, I've seen that there is always a black line to line up the crown and flint objective. If I cover the whole thing with black.... :lol:

Here's a pic of my "Towatron" 60mm f/7 objective done up with a black Sharpie. The difference was amazing; so much darker background all the way to the edges of the FOV.
Objective.jpg


Hope you get some clear skies to test it out, I believe it will work out well for you!

All the best,
Mark

"The Hankmeister" Celestron 8SE, orange tube Vixen made C80, CG4 & AZ-EQ5 mounts.
Too much Towa glass/mirrors.

H/A - PST stage 2 mod with a Baader 90mm ERF on a Celestron XLT 102 (thanks Mike!)
Ca-K - W/O 61mm, Antares 1.6 barlow, Baader 3.8 OD and Ca-K filters with a ZWO ASI174mm.
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Re: Blackening lens edges

#13

Post by John Baars »


Thefatkitty wrote: Fri Oct 30, 2020 10:33 pm I've seen that there is always a black line to line up the crown and flint objective. If I cover the whole thing with black....
Thanks.
Yes, there were black pencil lines on the side for lining up.
So I pasted a very thin sticker on the side, as you can see in the third picture. After blackening I removed the sticker. And the line is white/ grey now. :D

I hope the blackening will make at least a bit of difference!! I hear different stories about it. From "no difference" to a "big difference". We will see.
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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Re: Blackening lens edges

#14

Post by Thefatkitty »


John, I didn't even notice; that is brilliant! Been a long week ;)

Hope it works for you, looking forward to hearing your results.

All the best,
Mark

"The Hankmeister" Celestron 8SE, orange tube Vixen made C80, CG4 & AZ-EQ5 mounts.
Too much Towa glass/mirrors.

H/A - PST stage 2 mod with a Baader 90mm ERF on a Celestron XLT 102 (thanks Mike!)
Ca-K - W/O 61mm, Antares 1.6 barlow, Baader 3.8 OD and Ca-K filters with a ZWO ASI174mm.
W/L - C80-HD with Baader 5.0 & 3.8 Solar film, Solar Continuum 7.5nm and UV/IR filters with a Canon EOS 550D.

Oh yeah, and Solar Cycle 25 :D
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Re: Blackening lens edges

#15

Post by Lady Fraktor »


Just do something like this after blackening the edges Mark :)
IMG_2719.png
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
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Re: Blackening lens edges

#16

Post by John Baars »


Ylem wrote: Fri Oct 30, 2020 7:49 pm More gooder is not always gooder LOL
I think Uncle Rod said something like that 🤣

IMHO, if you know what you are doing, or have other reasons to disassemble, then go for it :)

Otherwise, leave good be ;)
Thanks Ylem,

Very wise remarks of you and Uncle Rod. Complete laymen should not do these kind of operations.
In this case the owner knew what he was doing.
viewtopic.php?f=61&p=114261#p114261
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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Re: Blackening lens edges

#17

Post by John Baars »


DeanD wrote: Thu Oct 29, 2020 1:09 am Hi John,

Looks interesting: the second image certainly would indicte that there is likely to be less scattered light. I'll be interested in your viewing experience: whether you can notice a difference.

Let us know how you go,

All the best,

Dean
Did some testing the other night. I could easily make out tens of stars in M36, M37 and M38 with the Moon nearby. What convinced me was the fact that I could go as deep as magnitude 12,2 in the Pleiades with the Moon standing 6,5 degrees away. I had not expected that. I think transparancy helped a bit, but this was quite standing out, for I wasn't used to that.

On the other hand.......with axial coma nearly cleared out of the way I could make out that the instrument suffered of more sferical aberration than I thought. It floats between 0.25 and 0.3 waves under correction, both for the lower order and the higher order.

Sketch of Capella at 300X
Testbeeld2 150 F5.jpg
Testbeeld2 150 F5.jpg (3.27 KiB) Viewed 4169 times
The remnants of the axial coma can bee seen by the absence of narrow light arcs in the second and third diffraction rings as well as the slightly narrower and darker first diffraction ring on the left side.(270 degrees) Spherical aberration can be seen here as the rather fat first diffraction ring and the rather bright existence of the second and third diffraction ring. This irrevocably indicates a Strehl below 0.8

But never mind, I enjoy the telescope anyhow :D
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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Re: Blackening lens edges

#18

Post by Bigzmey »


For a mass produced rich field fast achro your test results are likely above the average John. I love mine 150ST for what it does best - wide field views of nebula and open clusters. It also does surprisingly good on faint galaxies. But, high power views of Moon and planets - just painful. :lol:
Scopes: Stellarvue: SV102ED; Celestron: 9.25" EdgeHD, 8" SCT, 150ST, Onyx 80ED; iOptron: Hankmeister 6" Mak; SW: 7" Mak; Meade: 80ST.
Mounts: SW: SkyTee2, AzGTi; iOptron: AZMP; ES: Twilight I; Bresser: EXOS2; UA: MicroStar.
Binos: APM: 100-90 APO; Canon: IS 15x50; Orion: Binoviewer, LG II 15x70, WV 10x50, Nikon: AE 16x50, 10x50, 8x40.
EPs: Pentax: XWs & XFs; TeleVue: Delites, Panoptic & Plossls; ES: 68, 62; Vixen: SLVs; Baader: BCOs, Aspherics, Mark IV.
Diagonals: Baader: BBHS mirror, Zeiss Spec T2 prism, Clicklock dielectric; TeleVue: Evebrite dielectric; AltairAstro: 2" prism.
Filters: Lumicon: DeepSky, UHC, OIII, H-beta; Baader: Moon & SkyGlow, Contrast Booster, UHC-S, 6-color set; Astronomik: UHC.

Observing: DSOs: 3106 (Completed: Messier, Herschel 1, 2, 3. In progress: H2,500: 2180, S110: 77). Doubles: 2382, Comets: 34, Asteroids: 255
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Lady Fraktor Slovakia
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Re: Blackening lens edges

#19

Post by Lady Fraktor »


"But never mind, I enjoy the telescope anyhow"

This is the main thing with any telescope, as long as you enjoy using it, it is a great telescope!
See Far Sticks: Antares Elita 103/1575, AOM FLT 105/1000, Bresser BV 127/1200, Nočný stopár 152/1200, Vyrobené doma 70/700, Stellarvue NHNG DX 80/552, TAL RS100/1000, Vixen SD115s/885
EQ: TAL MT-1, Vixen SXP, AXJ, AXD
Az/Alt: AYO Digi II/ Argo Navis, Stellarvue M2C/ Argo Navis
Tripods: Berlebach Planet (2), Uni 28 Astro, Report 372, TAL factory maple, Vixen ASG-CB90, Vixen AXD-TR102
Diagonals: Astro-Physics, Baader Amici, Baader Herschel, iStar Blue, Stellarvue DX, Takahashi prism, TAL, Vixen flip mirror
Eyepieces: Antares to Zeiss
The only culture I have is from yogurt
My day was going well until... people
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John Baars Netherlands
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Re: Blackening lens edges

#20

Post by John Baars »


Bigzmey wrote: Wed Nov 04, 2020 8:28 pm For a mass produced rich field fast achro your test results are likely above the average John. I love mine 150ST for what it does best - wide field views of nebula and open clusters. It also does surprisingly good on faint galaxies. But, high power views of Moon and planets - just painful. :lol:
I would say my telescope is not standard anymore. :D
Apart from the blackening I corrected the axial coma it suffered from. I had to add some 0.02 mm extra spacing underneath one spacer.The spacers within are made of simple plastic and seem to be of a standard thickness. It was clear that the manufacturer tested the lens on an optical bench for the best image, I could see by the markings on the side.

What struck me was the quite rough way the cell was casted and milled on the inside. I will not be surprised if tiny protrusions affected the position of the lens in the cell. Some black paint residue's affected this position too. ( some pinching) I had to use some sanding and polishing paper to smoothen it. After this treatment the lens slid smoothly back into his cell, without bumping into the cell-wall. For short: one can do a lot for themselves.

With powers up to 150X (200X with superb seeing and transparancy) the views of Mars, Saturn, Moon are quite palatable, if one is capable to turn a blind eye to CA. Even Venus was all right. No difference with an APO on Uranus and Neptune. Jupiter, with its low surface contrasts should not be taken to 150X and is at its best at 120X. My 120mm Evostar beats him on all Planetary and Lunar views of course, but still I am not dissatisfied.

I love its performance on wide fields, faint galaxies, open clusters and some nebulae. It even perfoms well on one-arcsecond- doubles.

If I was told to spend a year on a desolate island and was allowed to bring along this 150 f/5 only, I wouldn't blink an eye. :lol:
Refractors in frequency of use : *SW Evostar 120ED F/7.5 (all round ), * Vixen 102ED F/9 (vintage), both on Vixen GPDX.
GrabnGo on Alt/AZ : *SW Startravel 102 F/5 refractor( widefield, Sun, push-to), *OMC140 Maksutov F/14.3 ( planets).
Most used Eyepieces: *Panoptic 24, *Morpheus 14, *Leica ASPH zoom, *Zeiss barlow, *Pentax XO5.
Commonly used bino's : *Jena 10X50 , * Canon 10X30 IS, *Swarovski Habicht 7X42, * Celestron 15X70, *Kasai 2.3X40
Rijswijk Public Observatory: * Astro-Physics Starfire 130 f/8, * 6 inch Newton, * C9.25, * Meade 14 inch LX600 ACF, *Lunt.
Amateur astronomer since 1970.
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