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Update on my SW ED150 order...

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#326 jrbarnett

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Posted 05 August 2018 - 05:30 PM

Out of curiosity, if anyone from Skywatcher is following this thread, what is the specification for the focuser.  Specifically how long should the drawtube be?  How much travel should the focuser draw tube have?  I am trying to figure out whether either of the mothballed Feathertouch focusers I have in the garage will suffice.  I'd like to do that prior to committing to buying an adapter.

 

Thanks!

 

- Jim


 

#327 T1R2

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Posted 05 August 2018 - 05:58 PM

Just a side note Jim, when I received my AR127 it showed red /magenta lunar rim on a last quarter moon in a 20mm ep, then I collimated it with high power later on and it was ok. This was before I had any experience collimating a refractor and initial scanning of the sky at low to med powers I thought everything was ok. Also when I collimated the scope it was only the tilt collimation that fixed the problem not centering screws. It did take a couple of nights to really hone it in good but once I did it never showed red/ magenta color again, occasionally when I do a full disassemble /cleaning I get the centering off and get the red/green/ blue prism effect on Jupiter and brighter stars, but I just take the lens apart and try again and it usually fixes it more or less and I usually leave it the way it is unless the prism effect is extreme or I plan on doing a lot of planetary viewing because low power star cluster viewing is not harmed too much by a small amount of decentering.

 

I think that the Chartreuse/yellow could be lateral color of the ep coming thru and although my scope is very well collimated I still get lateral color from some low power ep's from time to time, but it seems to also be lessened when collimation is good, not as thick and only a sliver compared to when collimation is more off, it seems to be thicker and rising higher from the edge of the moon. It seems good collimation goes along way to reduce some of the initial color aberrations.


 

#328 Jimmy462

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Posted 05 August 2018 - 06:52 PM

Now to business.  Here's the factual preliminary testing and first light report.

 

>snip<

 

Initial Star Test:  Though later in my session things calmed down a bit, seeing was never really optimal for star testing.  Nonetheless I made the attempt unfiltered and with two different green filters (Wratten 58 and Wratten 11).  I used 240x (5mm Nagler Type 5).  I did not center mask the optic, yet.  However preliminary here's what I saw.  The optics are not rough.  Not the smoothest I've owned by polish looks decent.  The transitions between rings are "unhairy" even in chancy seeing.  Spherical correction likewise wasn't perfect.  I noted a bit over-correction; that is the diffraction pattern was softer a bit inside of focus than outside of focus.  It reminds me of my TV-102, which is not perfect and is also slightly over-corrected, though to a lesser degree than the ED150.  I want to wait for better seeing before reaching a definitive conclusion on figure quality, but if I had to go out on a limb, I rate the TV-102 as ~1/6 wave.  I would put this optic somewhere between 1/4 wave and 1/6 wave, probably close to the center point (i.e., 1/5 wave) and maybe leaning to the 1/4 wave side.  A respectable large ED optic by any measure, and at this price (1670 Euros!) really quite impressive from the quality/price perspective.

 

Color Correction:  The elephant in the room on big ED doublets.  Yes, it shows secondary spectrum.  For visual use I would not call this an APO.  Nor would I call the Kunming 152ED an APO visually.  But how bad is the color error?  It's actually pretty interesting.  Out of focus you can encourage false color; violet with a tinge of red/magenta on on side of defocus and chartreuse/yellow on the other.  In focus on brilliant blue-white stars like Vega here's what I saw.  At 120x (10mm XW) there is a modestly saturated violet fringe.  At 240x it was much more pronounced, though the seeing wasn't doing me any favors by inducing random defocus which the damaged focuser wasn't up to allowing me to chase reliably for best focus, It's really not that bad, though.  As a benchmark let's say that the old Meade 127ED f/9 doublet, which on like targets shows a moderate (worse than modest) blue halo, rates a 5 (1-10 scale, 1 being worst and 10 being best color corrected).  This scope would be a 6.5 or maybe a 7, which is exactly where I would put the UO competitor too (though the images in the APM 152ED were warmer based on recollection from my recent dark sky trip where I was able to spend some time with the Kunming) than the images produced by this scope.  I would put the TEC 140ED at 7.5 to 8 on the same scale.  The FS-78 would rate as a 9 or better visually, again for reference.

 


>snip<

 

Regards,

 

JIm    

Hi Jim,

 

Sincere thanks for taking the time to perform all these tests and for reporting back for everyone! bow.gif waytogo.gif

 

In particular, thanks for the initial star test results and the initial chromatism reports, they're very helpful for my visual-observing non-imaging interests here. Curious if you could share with which eyepieces and diagonal(s) you were performing these tests?

 

Also, in regards to the, um, state-of-arrival of this package, you're clearly a more-determined and patient individual than myself in making-do with that damaged shipment, IMHO. That's quite the ongoing saga. FWIW, had it been me...after encountering the damaged case and focuser I'd have been on the phone with both the carrier and the shipper/reseller and, in this instance, the original manufacturer for solutions. (By way of example...when an order of Panasonic camera batteries arrived from their 46.8-mile trip from Manhattan last month in what appeared to have been a bubble envelope that had been run over by a fork-lift a claim call went out to Fedex [they requested emailed pictures of the package] and then B&H which resulted in B&H having already-heard from the carrier about the damaged delivery and a fresh boxed replacement set of batteries immediately went out and arrived with a prepaid return label for the damaged goods. Turnaround time, two days from original delivery...with the shipper then taking up matters business-to-business with the carrier.)

 

Anyhoo, I hope this has a happy ending for you. And sincerest thanks again for sharing your viewing experiences!

 

Very best, smile.gif

Jimmy G

 

Edit: Oop, I see now..."240x (5mm Nagler Type 5)", "120x (10mm XW)"...sorry for the earlier question.


Edited by Jimmy462, 05 August 2018 - 07:49 PM.

 

#329 hfjacinto

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Posted 05 August 2018 - 07:03 PM

I'm with Jimmy, I would have sent everything back.


 

#330 starman876

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Posted 05 August 2018 - 08:10 PM

I think like most you got to try the scope out before you send it back.  I know I would. 


 

#331 Jimmy462

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Posted 05 August 2018 - 08:43 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

Hrmm...seems another SW150 is having Objective alignment/collimation issues straight from the factory, this time with no reseller checking prior to customer shipment...

 

The Skywatcher Evostar ED150 DS Pro Is Here ! - Page 3 - Discussions - Scopes / Whole setups - Stargazers Lounge:

https://stargazerslo...comment-3484917

 

... :\

 

As found here in another CN thread...

 

152 ed apo telescopes - Page 2 - Refractors - Cloudy Nights: #42

https://www.cloudyni...-2#entry8750083

 

...hopefully SW can implement some extra QC here?!


 

#332 Daniel Mounsey

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Posted 05 August 2018 - 09:12 PM

...hopefully SW can implement some extra QC here?!

 

Absolutely. This is why SW is making sure the shipping situation gets worked out first here in the US to minimize any possibilities. IMO it’s better to wait and do it right. 


Edited by Daniel Mounsey, 05 August 2018 - 09:12 PM.

 

#333 starman876

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Posted 05 August 2018 - 11:00 PM

...hopefully SW can implement some extra QC here?!

 

Absolutely. This is why SW is making sure the shipping situation gets worked out first here in the US to minimize any possibilities. IMO it’s better to wait and do it right. 

Foam sheets around the first box is how to do it right. I have shipped dozens and dozens of scopes that way. A lot of them antique scopes.  They arrived without harm.   If those aluminum cases the scopes comes in is like other skywatcher thin cases I have seen I would say they are for storage only and I would never ship anything in them unless extra padding on the inside and outside.  This is not rocket science guys. You can figure it out.  


 

#334 jrbarnett

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Posted 05 August 2018 - 11:02 PM

Hi Jim,

 

Sincere thanks for taking the time to perform all these tests and for reporting back for everyone! bow.gif waytogo.gif

 

In particular, thanks for the initial star test results and the initial chromatism reports, they're very helpful for my visual-observing non-imaging interests here. Curious if you could share with which eyepieces and diagonal(s) you were performing these tests?

 

Also, in regards to the, um, state-of-arrival of this package, you're clearly a more-determined and patient individual than myself in making-do with that damaged shipment, IMHO. That's quite the ongoing saga. FWIW, had it been me...after encountering the damaged case and focuser I'd have been on the phone with both the carrier and the shipper/reseller and, in this instance, the original manufacturer for solutions. (By way of example...when an order of Panasonic camera batteries arrived from their 46.8-mile trip from Manhattan last month in what appeared to have been a bubble envelope that had been run over by a fork-lift a claim call went out to Fedex [they requested emailed pictures of the package] and then B&H which resulted in B&H having already-heard from the carrier about the damaged delivery and a fresh boxed replacement set of batteries immediately went out and arrived with a prepaid return label for the damaged goods. Turnaround time, two days from original delivery...with the shipper then taking up matters business-to-business with the carrier.)

 

Anyhoo, I hope this has a happy ending for you. And sincerest thanks again for sharing your viewing experiences!

 

Very best, smile.gif

Jimmy G

 

Edit: Oop, I see now..."240x (5mm Nagler Type 5)", "120x (10mm XW)"...sorry for the earlier question.

No worries.  I used a series of eyepieces including a 5mm Nagler Type 5, 10mm Pentax XW, 16mm Nagler Type 5, 30mm Leitz Astroplanokular and Vixen 42mm LVW.  The diagonal was a Baader Maxbright.

 

As for the damaged case, here's the thing.  The case is pretty crummy to be honest.  Super thin plywood skinned with aluminum one grade above aluminum foil, with poorly applied cheap black rubberized foam lining the interior, really sloppily put together (the lid fits and latched poorly though in my case that could be due to rough handling), etc.  Even my good cases (Pelicans, Porta-Braces, Scopeguards, etc.) look like they've been well sued because, well, I use them in harsh environments.

 

If you received one of these Skywatcher cases in perfect condition, it's flimsy construction and awkward dimensions pretty much insure that it won't look pretty for long.  I look at it this way - UPS rather than me put the first ding of many dings to come in the case.

 

The focuser, on the other hand, is aggravating.  The damage to the unit makes the almost unusable at high magnification, as achieving best focus often proves impossible because the focal point is between detentes.  To make matters worse, it's not plug and play like it is on the other Evostar scopes that use the unit.  On the big 150 the unit appears to be mounted (permanently?) to an adapter segment that bolts into the tube rear plate.  Put another way, that means there's likely no easy aftermarket swap option.  Similarly I'll bet that the prospect of getting a spare, with the scope being so new, is pretty low.

 

Best,

 

Jim   


 

#335 glend

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Posted 05 August 2018 - 11:22 PM

Ron, at Moonlight, seems to be able to handle any adaptor problem. He will see this as an opportunity.  Perhaps SW should sell these scopes without a focuser, and let buyers pick and play from the market.


 

#336 John Huntley

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Posted 06 August 2018 - 04:28 AM

I think the 3rd party focuser manufacturers will quickly develop a flange to allow their units to be fitted to the ED150, if the scope becomes popular. From what I can see, they need to develop a replacement for the section that I have indicated below, to interface with their focusers. The stock SW focuser supplied threads onto this piece and it's attached to the next section with 6 hex screws. A rotatable upgrade would be nice smile.gif

 

The other scope in the photo is my TMB/LZOS 130 F/9.2 triplet by the way.

 

 

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#337 CHASLX200

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Posted 06 August 2018 - 05:16 AM

No worries.  I used a series of eyepieces including a 5mm Nagler Type 5, 10mm Pentax XW, 16mm Nagler Type 5, 30mm Leitz Astroplanokular and Vixen 42mm LVW.  The diagonal was a Baader Maxbright.

 

As for the damaged case, here's the thing.  The case is pretty crummy to be honest.  Super thin plywood skinned with aluminum one grade above aluminum foil, with poorly applied cheap black rubberized foam lining the interior, really sloppily put together (the lid fits and latched poorly though in my case that could be due to rough handling), etc.  Even my good cases (Pelicans, Porta-Braces, Scopeguards, etc.) look like they've been well sued because, well, I use them in harsh environments.

 

If you received one of these Skywatcher cases in perfect condition, it's flimsy construction and awkward dimensions pretty much insure that it won't look pretty for long.  I look at it this way - UPS rather than me put the first ding of many dings to come in the case.

 

The focuser, on the other hand, is aggravating.  The damage to the unit makes the almost unusable at high magnification, as achieving best focus often proves impossible because the focal point is between detentes.  To make matters worse, it's not plug and play like it is on the other Evostar scopes that use the unit.  On the big 150 the unit appears to be mounted (permanently?) to an adapter segment that bolts into the tube rear plate.  Put another way, that means there's likely no easy aftermarket swap option.  Similarly I'll bet that the prospect of getting a spare, with the scope being so new, is pretty low.

 

Best,

 

Jim   

I don't even want the case. Just something else in my way with a 100 boxes i already have laying around.  Just pack my scope in double boxes and get it to me before i change my mind and pay off a 7K credit card bill.  Never in my life have i ever not paid in full every month and i want that monkey off my back.


 

#338 CHASLX200

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Posted 06 August 2018 - 05:19 AM

I think the 3rd party focuser manufacturers will quickly develop a flange to allow their units to be fitted to the ED150, if the scope becomes popular. From what I can see, they need to develop a replacement for the section that I have indicated below, to interface with their focusers. The stock SW focuser supplied threads onto this piece and it's attached to the next section with 6 hex screws. A rotatable upgrade would be nice smile.gif

 

The other scope in the photo is my TMB/LZOS 130 F/9.2 triplet by the way.

So the white part won't unscrew from the black part?  I am not pikcy about a focuser so i am sure the stock one would be fine with me. I am not crazy about spending $300 for another focuser. I have 2 fine focus diagonals anyways.


 

#339 John Huntley

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Posted 06 August 2018 - 05:26 AM

So the white part won't unscrew from the black part?  I am not pikcy about a focuser so i am sure the stock one would be fine with me. I am not crazy about spending $300 for another focuser. I have 2 fine focus diagonals anyways.

Yes it does unscrew at the junction of the white and black parts. The thread is around 100mm in diameter (guessed not measured !).


Edited by John Huntley, 06 August 2018 - 05:27 AM.

 

#340 CHASLX200

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Posted 06 August 2018 - 05:34 AM

Yes it does unscrew at the junction of the white and black parts. The thread is around 100mm in diameter (guessed not measured !).

Good to know.


 

#341 Bomber Bob

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Posted 06 August 2018 - 08:41 AM

As for the damaged case, here's the thing.  The case is pretty crummy to be honest.

 

I thought it looked cheap & flimsy compared to the APM 152.  Honestly, I only use mine for at-home storage.  For car rides to dark sites, my 152 will be on the back (bench) seat of my VW Touareg, wrapped in towels, and strapped-in by the seat-belts.  No offense to anyone, but these aren't antique Clark refractors.  Not gonna abuse mine, but it's gonna get used, so the OTA is gonna be prepped for quick set up out in the country.


 

#342 starman876

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Posted 06 August 2018 - 09:01 AM

As for the damaged case, here's the thing.  The case is pretty crummy to be honest.

 

I thought it looked cheap & flimsy compared to the APM 152.  Honestly, I only use mine for at-home storage.  For car rides to dark sites, my 152 will be on the back (bench) seat of my VW Touareg, wrapped in towels, and strapped-in by the seat-belts.  No offense to anyone, but these aren't antique Clark refractors.  Not gonna abuse mine, but it's gonna get used, so the OTA is gonna be prepped for quick set up out in the country.

Just about anyone that has had one of these cases have seen some damage to them.   I think they are more for looks.


 

#343 RAKing

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Posted 06 August 2018 - 09:04 AM

Just about anyone that has had one of these cases have seen some damage to them.   I think they are more for looks.

Agreed!  The aluminum "foil" case that came with my SW 120ED is still sitting in the shipping box.  Mine also received its first ding courtesy of UPS.

 

I think the best thing you can do is simply consider this case to be an "extra shipping carton". tongue2.gif

 

Cheers,

 

Ron


 

#344 hfjacinto

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Posted 06 August 2018 - 09:52 AM

Agreed!  The aluminum "foil" case that came with my SW 120ED is still sitting in the shipping box.  Mine also received its first ding courtesy of UPS.

 

I think the best thing you can do is simply consider this case to be an "extra shipping carton". tongue2.gif

 

Cheers,

 

Ron

I'm surprised about the cases. I have the 120MM EON and the case is pretty well built and thick. Its heavy and while it has scratches from transportation it closes and has no gouges. Same with the Lunt cases, pretty tough.


 

#345 garret

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Posted 06 August 2018 - 09:58 AM

 

Initial Star Test:  Though later in my session things calmed down a bit, seeing was never really optimal for star testing.  Nonetheless I made the attempt unfiltered and with two different green filters (Wratten 58 and Wratten 11).  I used 240x (5mm Nagler Type 5).  I did not center mask the optic, yet.  However preliminary here's what I saw.  The optics are not rough.  Not the smoothest I've owned by polish looks decent.  The transitions between rings are "unhairy" even in chancy seeing.  Spherical correction likewise wasn't perfect.  I noted a bit over-correction; that is the diffraction pattern was softer a bit inside of focus than outside of focus.  It reminds me of my TV-102, which is not perfect and is also slightly over-corrected, though to a lesser degree than the ED150.  I want to wait for better seeing before reaching a definitive conclusion on figure quality, but if I had to go out on a limb, I rate the TV-102 as ~1/6 wave.  I would put this optic somewhere between 1/4 wave and 1/6 wave, probably close to the center point (i.e., 1/5 wave) and maybe leaning to the 1/4 wave side.  A respectable large ED optic by any measure, and at this price (1670 Euros!) really quite impressive from the quality/price perspective.

 

Color Correction:  The elephant in the room on big ED doublets.  Yes, it shows secondary spectrum.  For visual use I would not call this an APO.  Nor would I call the Kunming 152ED an APO visually.  But how bad is the color error?  It's actually pretty interesting.  Out of focus you can encourage false color; violet with a tinge of red/magenta on on side of defocus and chartreuse/yellow on the other.  In focus on brilliant blue-white stars like Vega here's what I saw.  At 120x (10mm XW) there is a modestly saturated violet fringe.  At 240x it was much more pronounced, though the seeing wasn't doing me any favors by inducing random defocus which the damaged focuser wasn't up to allowing me to chase reliably for best focus, It's really not that bad, though.  As a benchmark let's say that the old Meade 127ED f/9 doublet, which on like targets shows a moderate (worse than modest) blue halo, rates a 5 (1-10 scale, 1 being worst and 10 being best color corrected).  This scope would be a 6.5 or maybe a 7, which is exactly where I would put the UO competitor too (though the images in the APM 152ED were warmer based on recollection from my recent dark sky trip where I was able to spend some time with the Kunming) than the images produced by this scope.  I would put the TEC 140ED at 7.5 to 8 on the same scale.  The FS-78 would rate as a 9 or better visually, again for reference.

Other reviewers rated this scope much higher, I think this scope (sample) is performing as it should performing for the price you pay; nothing very special except this is still a 150mm refractor.

I bet the next year pricing will be higher because of better packaging and more attention to exact collimation prior final (customer) shipment.

 

Garrett


 

#346 Jeff B

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Posted 06 August 2018 - 10:14 AM

Jimmy, the artifacts visually seen in the first link you referenced in posting #331 is probably coma, around 1/4 to 1/6 wave.  Again, I see no mention of astigmatism or its visual symptoms.

 

Sure seems that the packaging is letting down a good scope.

 

Regarding the comments about how such a poor shipping container could happen at a company with a lot of experience like SW, well, there is always a cost pressure and sometimes one side of a business does not communicate very well with another side of a business (really?  No way!).  But that's not an excuse, just an observation I've seen myself in business.  The good, well run businesses take care of the issue and learn not to do it again.  But the zeal to ship product is there, and as we used to say sometimes, "There's never enough time or money to do it right the first time, but there's always enough time and money to do it right the second time."   Or, put a spin on it.  we used to say "ship and fix later".  That got spun 30 years later to "Launch and Learn." grin.gif

 

Jeff


Edited by Jeff B, 06 August 2018 - 10:15 AM.

 

#347 John Huntley

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Posted 06 August 2018 - 10:27 AM

Other reviewers rated this scope much higher,...

Did they ?

 

My reading of Jim's report is that the Skwatcher ED150 with it's damaged focuser and under variable seeing was rated, under Jim's scale, as 6.5-7 out of 10. Jime felt that this was a  similar result to what the 152 ED UO doublet sold by APM would have achieved. By comparison Jim put the old Meade 127ED F/9 at 5 and the 140 Tec triplet at 7.5-8.

 

Sounds reasonably encouraging to me, for what the ED150 costs and the move to an unknown ED glass type.

 

The 2 ED150's that I've used showed a similar level of CA control to my ED120 and, from reading Jim's description, probably a similar level to his example.

 

Apologies if I have misinterpreted Jim's reporting on his example undecided.gif


Edited by John Huntley, 06 August 2018 - 10:30 AM.

 

#348 Jeff B

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Posted 06 August 2018 - 10:43 AM

Ah, John, I see that was your review that Jimmy referenced.  

 

One thing I learned with with my APM/TMP triplets was that the last visible optical artifact to go away during the cool down of the objective was a touch, maybe 1/6 the wave, of coma (before that, significant under-correction was seen).  After a while though it would typically disappear unless the outside temperature dropped too quickly (in which case the coma was typically masked by undercorrection).  I attribute this to the differing thermal properties of the glasses and the design of the cell holding them.  So, maybe, with time, that bit of coma you see will go away or lessen to a degree.

 

Jeff


 

#349 John Huntley

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Posted 06 August 2018 - 11:09 AM

Ah, John, I see that was your review that Jimmy referenced.  

 

One thing I learned with with my APM/TMP triplets was that the last visible optical artifact to go away during the cool down of the objective was a touch, maybe 1/6 the wave, of coma (before that, significant under-correction was seen).  After a while though it would typically disappear unless the outside temperature dropped too quickly (in which case the coma was typically masked by undercorrection).  I attribute this to the differing thermal properties of the glasses and the design of the cell holding them.  So, maybe, with time, that bit of coma you see will go away or lessen to a degree.

 

Jeff

I've not seen that effect with my TMB/LZOS 130 F/9.2 to date Jeff. I usually give it 30-50 minutes to cool before use. The longer time in the winter months of course. The optical performance of the 130 is very much like that of my Tak FC100DL except with 30mm more of it smile.gif


Edited by John Huntley, 06 August 2018 - 11:11 AM.

 

#350 Jeff B

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Posted 06 August 2018 - 11:30 AM

I've not seen that effect with my TMB/LZOS 130 F/9.2 to date Jeff. I usually give it 30-50 minutes to cool before use. The longer time in the winter months of course. The optical performance of the 130 is very much like that of my Tak FC100DL except with 30mm more of it smile.gif

I should have been more specific John, I saw it the most with the 175 F8, to a lesser degree with the 152 F8 and not really with the 130 F 9.2 (though its design is less "sporty" than the other two).  The 130 F 9.2 to me would be good "reference standard" to compare others to.  A great scope.

 

Jeff


 


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