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Update on my SW ED150 order...

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#1 jrbarnett

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Posted 22 July 2018 - 01:29 PM

TS, working with SW Europe, informed me Friday that they have successfully realigned the optics.  I've asked that they share with me the instructions SW shared with the TS technician, just in case I ever need to do it myself.  If I receive it I'll share to benefit other future owners.

 

No shipping notice yet, but I expect to receive shipping information early next week and will share the progress, unboxing experience, artificial star test (first thing I will check when it arrives will be alignment of the optics), and if all is well, initial observing reports.

 

If the scope arrives misalligned, I've pretty much decided to exercise my right under EU law to revoke the transaction and return the item for a refund (14 days after receipt under EU law).  So fingers crossed that this one arrives ready to play.  If I do have to return it, I'll probably wait to let the initial teething pains get sorted and for the impact of a $2k entrant in the 6" ED doublet segment to pressure segment prices on all segment participants down.

 

More to come.

 

Best,

 

Jim


 

#2 Axunator

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Posted 22 July 2018 - 02:46 PM

Jim - let's hope it doesn't get to that and the scope is fine, but if you need to return I have no doubt that TS will refund you. That's how things work in EU wink.gif  You can return a mail order for a full refund within those 14 days even if it works fine, if you just feel like not keeping it.


 

#3 CHASLX200

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Posted 22 July 2018 - 03:18 PM

Lets hope this does not turn into another Meade 7" ED nitmare were the lens were always out of collimation until they had the new cell fix.


 

#4 John Huntley

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Posted 22 July 2018 - 04:13 PM

Lets hope that all dealers check the collimation of the ED150's before they ship.

 

Drop shipping will simply not be good enough for this one.


 

#5 Scott in NC

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Posted 22 July 2018 - 04:19 PM

Best of luck, Jim!  We're all eagerly awaiting your findings.


 

#6 jay.i

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Posted 22 July 2018 - 04:24 PM

Fingers crossed for a collimated cell. We need the word of The Most Interesting Blowhard In The Universe!

 

 

 

grin.gif


Edited by jay.i, 22 July 2018 - 04:24 PM.

 

#7 Bomber Bob

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Posted 22 July 2018 - 04:24 PM

These 6" lenses are heavy, and if a cell allows slippage...  the elements have to be precisely aligned.  My Goto 60mm is a contact doublet that's much lighter, yet they can slide out of the original alignment, and the image suffers.  I taped them together, but I guess that the 6" lens is too large for that?  And, if the cell holds the lens tightly, how does that affect swelling on hot nights?


 

#8 jrbarnett

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Posted 22 July 2018 - 05:39 PM

I also have one promise for anyone following my report - no matter how good - or bad - the result, the report will feature NO EXCLAMATION POINTS.

 

Likewise, no "tack sharps," "diamonds on black velvets," "snap focuses" or "amazings (or similar enthusiastic epithets".  I have so many scopes, good and bad, a new one rarely excites me.  I won't be blinded by the "shock of the new".  Promise.

 

Please throw oiut any visual tests you would like me to conduct.  Here is what I am already planning:

 

1.  Artificial star collimation test immediately after unpacking.

2.  Vega at 300x+ (if collimated), ramped up progressively until I can see false color, assuming I don't see it under 300x of course.  I may.  I own and have owned plenty of scopes other users praise for being color free (Kunming 6" f/5.9 achromat, Vixen 102mm f/10 achromat, SV 80D f/9.4 achromat, Antares 105mm f/15 achromat, TEC 140ED, AT111EDT, AT72ED, Takhashi FS-60C, Synta ED100, etc.) where at some magnification I've been able to spot obvious false color.

3.  Jupiter - low contrast details at ramping magnification; image breakdown magnification under test conditions.

4.  Mars - assuming some contrast features have emerged from the dust tempest.  Again a progressive magnification ramp and based on disclosed/reported conditions.

5.  Proper star test (e.g., green filtered, sufficient magnification to be meaningful, etc.) to give an idea of the figure quality.

 

Please suggest a couple of tough dioubles under 2 arc seconds, both matched magnitude and disparate magnitude.  Try and flag some that are well positioned for a Northern Hemisphere observers observing this time of year between 9pm and 2am local time.

 

I also want to devise a way to test and a target that will pit the SW's greater light grasp but due to color blur and being built to a price, presumably slightly worse contrast against the TEC 140ED.  Also some lunar testing ideas would be great.  I will have the ability to simultaneously mount and do A:B observations at matched magnification using similar eyepieces (same design) in both scopes (and in any other refractors anyone wants to bring by to harass the newcomer with).

 

Plenty of subjective accounts of interesting objects too, of course.  We all know that if you have only one scope, it's the best scope in the world for you.  It's infinitely better than the alternative of being scopeless.  Like the song goes, "if you can't be with the one you love, honey, love the one you're with".  :grin:

 

- Jim   


 

#9 CHASLX200

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Posted 22 July 2018 - 05:45 PM

Make sure to run it up 100x per inch on a star and see how well the star image looks.  I always take my scopes to the max right away when i get a new one.  My TMB and Taks have no problem at 100x per inch.


 

#10 infamousnation

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Posted 22 July 2018 - 05:46 PM

Sounds like the eu takes consumer protection seriously.

Jim, how do you perform your artificial star test?
 

#11 glend

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Posted 22 July 2018 - 05:49 PM

Jim did you ask Teleskop-Services to do the Interferometrical  test of the ED150 (beyond the normal bench test and collimation), such as this service they supply at a cost (@ 249 euro).

 

https://www.teleskop...nd-mirrors.html

 

I would love to see that report.

 

Even for in stock scopes, Exports are usually delayed a couple of days because they need to get German Export approval to avoid charging EU VAT on the purchase.


Edited by glend, 22 July 2018 - 05:50 PM.

 

#12 Bomber Bob

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Posted 22 July 2018 - 05:55 PM

My TMB and Taks have no problem at 100x per inch.

 

Haven't had a chance to go above 83x / inch with my APM152.  But most of the refractors I've kept meet that limit, including my Vixen FL80S, which stayed sharp at 320x.


 

#13 Jeff B

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Posted 22 July 2018 - 06:11 PM

Hope all turns out well Jim and thanks for doing this.

 

"Please throw out any visual tests you would like me to conduct."

 

May I suggest:  First thing I always do is make a mask with a hole in the middle and use my Glatter (RIP) laser to check the focuser alignment with the center of the lens.  Second, I use my cheshire eyepiece to check if the reflection dots from the elements line up.  This gives me an indication as to the robustness of the mechanical design, care during fabrication and sensitivity to transport.

 

If it's possible to separate the lens cell from the tube, I can do DPAC testing for you as well if your being sporty.

 

Jeff


 

#14 Astrojedi

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Posted 22 July 2018 - 07:09 PM

I also have one promise for anyone following my report - no matter how good - or bad - the result, the report will feature NO EXCLAMATION POINTS.

 

Likewise, no "tack sharps," "diamonds on black velvets," "snap focuses" or "amazings (or similar enthusiastic epithets".  I have so many scopes, good and bad, a new one rarely excites me.  I won't be blinded by the "shock of the new".  Promise.

 

Please throw oiut any visual tests you would like me to conduct.  Here is what I am already planning:

 

1.  Artificial star collimation test immediately after unpacking.

2.  Vega at 300x+ (if collimated), ramped up progressively until I can see false color, assuming I don't see it under 300x of course.  I may.  I own and have owned plenty of scopes other users praise for being color free (Kunming 6" f/5.9 achromat, Vixen 102mm f/10 achromat, SV 80D f/9.4 achromat, Antares 105mm f/15 achromat, TEC 140ED, AT111EDT, AT72ED, Takhashi FS-60C, Synta ED100, etc.) where at some magnification I've been able to spot obvious false color.

3.  Jupiter - low contrast details at ramping magnification; image breakdown magnification under test conditions.

4.  Mars - assuming some contrast features have emerged from the dust tempest.  Again a progressive magnification ramp and based on disclosed/reported conditions.

5.  Proper star test (e.g., green filtered, sufficient magnification to be meaningful, etc.) to give an idea of the figure quality.

 

Please suggest a couple of tough dioubles under 2 arc seconds, both matched magnitude and disparate magnitude.  Try and flag some that are well positioned for a Northern Hemisphere observers observing this time of year between 9pm and 2am local time.

 

I also want to devise a way to test and a target that will pit the SW's greater light grasp but due to color blur and being built to a price, presumably slightly worse contrast against the TEC 140ED.  Also some lunar testing ideas would be great.  I will have the ability to simultaneously mount and do A:B observations at matched magnification using similar eyepieces (same design) in both scopes (and in any other refractors anyone wants to bring by to harass the newcomer with).

 

Plenty of subjective accounts of interesting objects too, of course.  We all know that if you have only one scope, it's the best scope in the world for you.  It's infinitely better than the alternative of being scopeless.  Like the song goes, "if you can't be with the one you love, honey, love the one you're with".  grin.gif

 

- Jim   

Jim, you are taking the fun out of CN by being so thoughtful and objective tongue.png


 

#15 Kunama

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Posted 22 July 2018 - 07:10 PM

Jim, are you expecting optical perfection while paying peanuts???? cool.gif   


 

#16 daveCollins

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Posted 22 July 2018 - 07:31 PM

These are observations from inside Washington DC.

 

Scope: TOA 150 B

Entries: I have included actual log entries as they were recorded at the eyepiece. I have not edited the entries.

Abbreviations: E means Ethos, so 6E is 6mm Ethos.

Format: 24 hour time : temperature in Fahrenheit : percent humidity : log entry

 

  • 6/14/2018
    • Xi Sco, STF 1998, HD 144069
    • AB (1.1" mag 4.15 and 4.87)
    • 2140 82° F 31% 2.5 Nagler two balls clearly resolved with black space between them. Sharper in 3.7E. Still resolved but barely.
  • 6/16/2018
    • Xi Sco, STF 1998, HD 144069
    • AB (1.1" mag 4.15 and 4.87)
    • 2135 83° F 40%  Immediate fantastic split with 3.7E. Wow. 2.5 Nagler shows 2 disks with a relatively large gap. 6E mostly a composite image. Not really a split.
  • 6/16/2018
    • BU 39, HD 144708
    • AB (3.3" mag 5.76 and 9.22)
    • 2151 83° F 40%  3.7E no secondary. 6E the secondary is an impossibly dim fine pinpoint.  8E the secondary is like a light house flashing on and off. Brighter than 6E.
  • 6/16/2018
    • STF 2055, HD 148857
    • AB (1.4" mag 3.90 and 5.15)
    • 2221 83° F 40%  Clean split, steady. 6E split is iffy in steady moments, but I'd call it a split. 2.5 Nagler split clean with obvious magnitude difference.
  • 6/16/2017
    • BU 1089, HD 158463
    • AB (1.5" mag 6.40 and 8.97)
    • 2302 82° F 41%  I tried everything but no secondary. Primary appears reddish and dim.
  • 6/16/2018
    • STF 2171, HD 158373
    • AB (1.5" mag 7.69 and 8.50)
    • 2315 82° F 41%  This pair was tough. Split with 3.7E. Stars dim. I may be viewing through clouds.
  • 6/29/2018 LZOS 175 (this is the only entry for this scope)
    • STF 2303, HD 168459
    • AB (1.6" mag 6.57 and 9.25)
    • 2222 87° F 45%  Not steady enough to split.
  • 7/7/2018  Same target as above
    • SFT 2303, HD 168459
    • AB (1.6" mag 6.57 and 9.25)
    • 2210 75° F 41%  Could not make split. Primary seemed well resolved.
  • 7/7/2018
    • STF 2262, HD 164765
    • AB (1.5" mag 4.8 and 5.3)
    • 2217 75° F 42%  6E more merged than separated. 3.7E great split, great pair. Equal brightness. 2.5 Nagler gave best image.
  • 7/7/2018
    • STF 2745, HD 200496
    • AB (2.5" mag 5.8 and 7.5)
    • 0002 71° F 51% Tough split with 8E. Primary much brighter than secondary. Secondary is a tiny pinpoint. During steady moments, impressive split with 3.7E.
  • 7/14/2018
    • STF 2643, HD 192007
    • AB (2.9" mag 6.9 and 9.4)
    • 2309 83° F 39% Secondary is a ghostly dim fine pointpoint in 8E.
  • 7/14/2018
    • STF 2744, HD 200375
    • AB (1.2" mag 6.4 and 7.3)
    • 2352 82° F 40% 6E mostly a composite, but when steady it is clearly two sars. 2.5 Nagler provided split but was not easy. 3.7E was a tough split.
  • 7/14/2018
    • STF 2770, HD 201719
    • AB (7.5" mag 7.51 and 10.84)
    • 0013 82° F 40% I can percieve the secondary with 10E. It is almost impossible to see.
  • 7/14/2018
    • STF 2944, HD 215812
    • AB (1.8" mag 7.2 and 7.7)
    • 0135 81° F 46% 10E shows the pair. Fantastic pair with 6E, two fine pinpoints

 

#17 mogur

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Posted 22 July 2018 - 09:04 PM

Jim, are you expecting optical perfection while paying peanuts???? cool.gif   

Merely performing a series of tests does not indicate any prior expectations. I'm sure the results will be objectively reported without prejudice. Sort of like when an auto magazine does a report on a new car. Acceleration, handling, interior & exterior dimensions, cargo capacity, etc. are all reported factually and the prospective purchaser can make their own judgement as to whether the car will meet their needs, or at least worth looking at in person.


 

#18 fred1871

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Posted 22 July 2018 - 09:40 PM

Interesting list of double star observations from daveCollins, but the effect of seeing appears to affect the results. This shows in the first two observations of Xi Scorpii on different dates: same, scope, same observer, same eyepieces, but a better split of the closer pair on one night compared to the other. Xi Sco would culminate around 40 degrees above the Southern horizon from Washington DC. Not the best altitude.... Petaluma CA I find is nearly as far North, less than a degree of latitude in it.

 

The seeing effect is I think the culprit in the failure to resolve the close and large brightness difference BU 1089.

Quote:

6/16/2017

    BU 1089, HD 158463
    AB (1.5" mag 6.40 and 8.97)
    2302 82° F 41%  I tried everything but no secondary. Primary appears reddish and dim.

 

I've observed this one a few years ago from my mid-30s South latitude, where it goes much higher in the sky. On a night of good air steadiness I was able to see the companion as a tiny point separated (just) from the primary at 228x with a 3.5mm Nagler on my 140mm refractor. The scope is an achromat, and definitely not Takahashi quality, but with superior seeing conditions it did the job on this difficult pair.

 

That points to the usual assessment problems. Seeing makes a big difference near the limits of what a scope can do. Doubles that don't show one night will split another night, same scope, etc etc. The significantly unequal ones are the trickiest. 


 

#19 Axunator

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Posted 23 July 2018 - 02:16 AM

Sounds like the eu takes consumer protection seriously.


They/we take lots of things seriously, like the size and shape of cucumbers considered eligible for human consumption.
 

#20 Psion

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Posted 23 July 2018 - 03:00 AM



If the scope arrives misalligned, I've pretty much decided to exercise my right under EU law to revoke the transaction and return the item for a refund (14 days after receipt under EU law). So fingers crossed that this

Jim


Yes, but you missed this therm 14 days from order.
 

#21 daveCollins

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Posted 23 July 2018 - 07:34 AM

Interesting list of double star observations from daveCollins, but the effect of seeing appears to affect the results. This shows in the first two observations of Xi Scorpii on different dates: same, scope, same observer, same eyepieces, but a better split of the closer pair on one night compared to the other. Xi Sco would culminate around 40 degrees above the Southern horizon from Washington DC. Not the best altitude.... Petaluma CA I find is nearly as far North, less than a degree of latitude in it.

 

The seeing effect is I think the culprit in the failure to resolve the close and large brightness difference BU 1089.

Quote:

6/16/2017

    BU 1089, HD 158463
    AB (1.5" mag 6.40 and 8.97)
    2302 82° F 41%  I tried everything but no secondary. Primary appears reddish and dim.

 

I've observed this one a few years ago from my mid-30s South latitude, where it goes much higher in the sky. On a night of good air steadiness I was able to see the companion as a tiny point separated (just) from the primary at 228x with a 3.5mm Nagler on my 140mm refractor. The scope is an achromat, and definitely not Takahashi quality, but with superior seeing conditions it did the job on this difficult pair.

 

That points to the usual assessment problems. Seeing makes a big difference near the limits of what a scope can do. Doubles that don't show one night will split another night, same scope, etc etc. The significantly unequal ones are the trickiest. 

I only included this list since a request was made for binary pairs less than 2 arcseconds apart. I thought it would be instructive to include the information from another 150mm scope.

 

Fred, I agree that seeing conditions are critical. With respect to BU 1089, I find this to be a particularly difficult pair. I think in my case that I am also effected by the brightness of the surrounding lights and so even if my seeing were a bit better, I might still have trouble with this pair. 

 

With respect to your last point, I also agree. In many reviews of scopes in these forums, it is the local seeing conditions which are being evaluated more than the scopes themselves. 

 

The last point I want to make is that it is always useful to see actual data from others, regardless of the observing location. I have posted a bunch of data points from Washington DC with specifics that will allow others to gain a little more insight as to what this scope can and can not do in a particular setting.


 

#22 Jimmy462

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Posted 23 July 2018 - 08:26 AM

>snip<

 

Please throw oiut any visual tests you would like me to conduct.  Here is what I am already planning:

 

>snip<

 

- Jim   

Hi Jim,

 

Firstly, many thanks from this "I'm coming from Newt/Dobs and am considering a wallet-friendly (well, to me) refractor in the 150mm-range" reader for your kind and generous considerations in offering up your to-come experiences with this scope. Many thanks in advance, kind sir.

 

Your 5-point list seems quite robust and comprehensive to my mind and should offer a well-rounded set of "observer experiences" to those of us considering this scope as an option. It certainly covers my big-3 curiosities...50x-per-inch performance, "high magnification" (i.e. 0.5mm exit pupil) planet performance and star test.

 

I greatly enjoyed your 20-page thread about the TEC 140 being the "greatest consumer telescope in history" and found myself recombing it last night to relocate for myself some of, what I considered, the more memorable and pertinent posts...to wit, your "anTECdote" post...

 

TEC 140 - the greatest consumer telescope in history? - Page 6 - Refractors - Cloudy Nights: #148

https://www.cloudyni...-6#entry6214995

 

...and your reply to Derek in regards to "polychromatic Strehls and spherochromatism"...

 

TEC 140 - the greatest consumer telescope in history? - Page 15 - Refractors - Cloudy Nights: #367

https://www.cloudyni...15#entry6226121

 

...both particularly informative in an already otherwise entertaining and educational conversation.

 

So, my only "add" would be to read about any side-by-side comparisons you might consider offering up against your TEC 140...sort of a "how the SW ED holds up against a, um, "visual observing benchmark" in the 140–152mm size range" if you think it fair. (I know, I know, I can almost hear the cries already, "Comparing an oiled FPL-53 Aplanatic Triplet with "focus shift less than 0.02% from 435nm to 1000nm" (from TEC User Manual) costing nearly thrice the price?!?! Apples and bananas, man!" Well, life is short and, yeah, I'd like hear how the new SW ED fares in reaching for a "brass ring" of its own!)

 

I, of course, will be on the look out for visual observation comparisons of the SW 150 ED against its more direct competitor, the APM/Lunt 152 ED, and for "color control" comparisons against a Newtonian, but methinks you've already loaded your plate aplenty here. smile.gif

 

Many thanks again for all your time and energies here! smile.gif

Jimmy G


Edited by Jimmy462, 23 July 2018 - 08:28 AM.

 

#23 jrbarnett

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Posted 23 July 2018 - 10:43 AM

Sounds like the eu takes consumer protection seriously.

Jim, how do you perform your artificial star test?

I use a Hubble artificial star. 

 

http://www.hubbleopt...cial-stars.html

 

I mount it on one side of the back garden where my astro-shed is, and mount the scope to be tested on the other.

 

I then check collimation by picking the smallest artificial star aperture that still gives clean rings, masking the others (the Hubble device has 5 different pinholes on its face of different diameters), centering artificial star in the scope's FOV, and confirming inside and outside of focus the Fresnel rings are concentric.

 

If you don't have an artificial star, one trick is to take a metallic colored glass ball Christmas tree ornament and hang it (surreptitiously) on a neighbor's tree within the line of sight where you will set up the telescope.  In bright sunlight the reflection off of the ornament makes a passable "artificial star".

 

The nice thing about a battery operated artificial star, though, is that it works day or night and in any weather.

 

Best,

 

Jim


 

#24 jrbarnett

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Posted 23 July 2018 - 10:48 AM

Jim did you ask Teleskop-Services to do the Interferometrical  test of the ED150 (beyond the normal bench test and collimation), such as this service they supply at a cost (@ 249 euro).

 

https://www.teleskop...nd-mirrors.html

 

I would love to see that report.

 

Even for in stock scopes, Exports are usually delayed a couple of days because they need to get German Export approval to avoid charging EU VAT on the purchase.

Thanks.  Yep I'm aware of the tax clearance process and customs document process on their end.  I did not ask for an interferometric report.  It would be nice, but at 1670 Euros I doubt they will want to throw in testing service for free, and I certainly don't want to pay an extra 250 Euros for peace of mind.  I'm also confident that that I can do a credible live sky star test on my end that will reveal any significant aberrations (e.g., SA) or issues (rough surface).

 

Regards,

 

Jim


 

#25 jrbarnett

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Posted 23 July 2018 - 10:59 AM

Make sure to run it up 100x per inch on a star and see how well the star image looks.  I always take my scopes to the max right away when i get a new one.  My TMB and Taks have no problem at 100x per inch.

I can do this, but what am I looking for in this test?

 

At some point any optic ceases to reveal additional detail and merely enlarges the image without showing anything new.  6" optics hit that point well before 600x irrespective of seeing.  Would I be trying to determine the magnification at which the transition to "empty" occurs?

 

Thanks!

 

- Jim


 


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