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APM 140 vs TS 150 (FPL-53 Doublets)

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#1 5th Gin

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Posted 26 July 2021 - 12:35 AM

I'm shopping for my second and backyard scope, and currently looking at the new TS 150mm f/8 doublet and the APM 140mm f/7 doublet. Looks like they both have FPL-53 glass and similar weight, but the APM is easier to purchase in the US and seems shorter. Wondering if the 10mm or mechanical qualities would make any difference? How much better are they compared to a 115mm triplet?

 

I'm happy with my first scope, an AT115EDT, which I hauled around mainly for DSO imaging with QHY 294M and Sony a7 FF OSCs, but occasionally also visual and planetary. Since I got a proper backyard and some more budget, I've been thinking about complimenting the 115mm with something more powerful as a wide/deep imaging or imaging/visual combo. However it would still be great if they can ride on my current CEM40 since better mounts like CEM70 are much more expensive and heavier. Also considering reflectors like EdgeHD, but I like the simplicity of refractors, and feel that the 8" is not as good as the large refractors due to CO and image circle (but does looks like a cost effective option for small objects), 9.25" is also too long for DSOs even with FF, and Maksutov-Newtonians seem quite heavy.


Edited by 5th Gin, 26 July 2021 - 01:26 AM.

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#2 F.Meiresonne

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Posted 26 July 2021 - 01:36 AM

The TS 150 mm F/8 will be probably taxing for a CEM40. Weight is 9 kg but it is  long scope, lever arm plays a roll too.

 

Can't find weight specs for the APM.

 

But CEM40 users will be able to provide more precise info.


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#3 Supernova74

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Posted 26 July 2021 - 03:19 AM

The APM 140 doublet weighs in at 8.8kg 


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#4 25585

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Posted 26 July 2021 - 03:53 AM

My choice is the 140.


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#5 Jon_Doh

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Posted 26 July 2021 - 08:37 AM

I have the APM 140 and it's built really well.  The focuser, although not a feathertouch, is smooth and handles my heavy eyepieces without any slipping.  The retractable dew shield is nice too.  I don't know how much you would lose over the 152.  Before purchasing mine I was considering the 152 and asked some folks who had looked through a 140 (TEC) and a 152 what the difference was in what you'd see and was told it was very minor. So, I bought the 140 due to it's smaller size and weight.

 

I also have a 120 and although the difference between it and the 140 is not mind blowing, it is noticeable so I think you would see a noticeable difference over your 115, but it wouldn't knock your socks off.  Some things do show up better in the 140 where the difference is more noticeable.  The Dumbbell is once such object.  In the 140 you can see it very well in my light polluted skies without a filter whereas the 120 benefits from a filter.  


Edited by Jon_Doh, 27 July 2021 - 08:16 AM.

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#6 Jeff B

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Posted 26 July 2021 - 09:13 AM

Based upon comparison of just the specs and price, the TS 150 doublet is the more attractive scope so go with the bigger aperture.  The TS is also directly "bino-friendly" which is a big deal for me.

 

I would love to test samples of both scopes.

 

Jeff


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#7 alphacentauri

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Posted 26 July 2021 - 10:46 AM

Hi

 

I asked a similar question to our forum here in Germany via astronomie.de.
I then learned from some users (owners) of the TS 150F8 FPL 53 that the TS is still very sharp and color-pure at 300 magnification. (no color)
I haven't read that from the APM SD APO 140 yet.
But the TS 150 is very long and the SD APO 140 is relatively short.

I would like to know if I write about google translate here, does it sometimes read funny from the sentence order in your translation and at all?
When I translate from English into German via google translater, your texts are sometimes translated very funny.(and somethimes I can't this understood

than I reed in English original and I understand sometimes better)

 

Regards 

 

Michael


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#8 5th Gin

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Posted 26 July 2021 - 09:09 PM

Based upon comparison of just the specs and price, the TS 150 doublet is the more attractive scope so go with the bigger aperture.  The TS is also directly "bino-friendly" which is a big deal for me.

 

I would love to test samples of both scopes.

 

Jeff

Oh why is it directly bino-friendly more than the APM?



#9 5th Gin

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Posted 26 July 2021 - 09:14 PM

Hi

 

I asked a similar question to our forum here in Germany via astronomie.de.
I then learned from some users (owners) of the TS 150F8 FPL 53 that the TS is still very sharp and color-pure at 300 magnification. (no color)
I haven't read that from the APM SD APO 140 yet.
But the TS 150 is very long and the SD APO 140 is relatively short.

I would like to know if I write about google translate here, does it sometimes read funny from the sentence order in your translation and at all?
When I translate from English into German via google translater, your texts are sometimes translated very funny.(and somethimes I can't this understood

than I reed in English original and I understand sometimes better)

 

Regards 

 

Michael

"I haven't read that from the APM" reads a bit funny but I didn't notice that until you mentioned about the google translate.

 

Do you have the link to the astronomie forum post? I can try to use google translate to understand it LOL.



#10 5th Gin

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Posted 26 July 2021 - 09:25 PM

I have the APM 140 and it's built really well.  The focuser, although not a feathertouch, is smooth and handles my heavy eyepieces without any slipping.  The retractable dew shield is nice too.  I don't know how much you would lose over the 152.  Before purchasing mine I was considering the 152 and asked some folks who had looked through a 140 (TEC) and a 152 what the difference was in what you'd see and was told it was very minor. So, I bought the 140 due to it's smaller size and weight.

 

I also have a 120 and although the difference between it and the 140 is mind blowing, it is noticeable so I think you would see a noticeable difference over your 115, but it wouldn't knock your socks off.  Some things do show up better in the 140 where the difference is more noticeable.  The Dumbbell is once such object.  In the 140 you can see it very well in my light polluted skies without a filter whereas the 120 benefits from a filter.  

Which TEC and 152 are you referring to? If the lower-spec (doublet, FPL-51, etc) 152mm is slightly better than the higher-spec (FPL-53/Fluorite triplet) TEC 140mm, sounds like the extra aperture is indeed useful here?



#11 dnrmilspec

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Posted 26 July 2021 - 10:46 PM

Also considering reflectors like EdgeHD, but I like the simplicity of refractors, and feel that the 8" is not as good as the large refractors due to CO and image circle (but does looks like a cost effective option for small objects), 9.25" is also too long for DSOs even with FF, and Maksutov-Newtonians seem quite heavy.

 

I know this is the refractor forum.  I love refractors.   I own about 9 or so of them including some in the size range your are considering.  But I could not let the above go without a bit of a reality check.

 

I will just speak about the 9.25. 

 

You mention that it is "too long for DSO's"  I respectfully disagree.  With the correct EP's it offers spectacular views of deep space objects.  Far superior light gathering to your proposed 6".  They are not even in the same class.  Add to it a F6.3 reducer and the difference is even more stark putting the focal length not too far off of that of your 150 refractor while even faster.  (1480mm versus 1200.)    The 9.25's have a real cult following and I can personally attest to the fact that for deep space objects it usually just blows away my 6" refractor.  My former copy had wonderful optics.    Even my 8" SCT is quite capable of embarrassing my good 150 refractor.  The 9.25 weighs just a hair less than the 150 you propose but it is much shorter and therefor much easier on your mount.  And likely to be noticeably more stable.  Simply put, you will just see a whole lot more through a 9.25" scope than you will through a 6" one.

 

I wish to join those who might say that while a 150 F-8 will definitely be an improvement over a 115 F/7, it will not be a real game changer except on some very specific objects.  You will notice a difference but nothing like what you would see with an 8" not to mention a 9.25" scope.  And for only 7 pounds more on your mount you could go to an 11" SCT and still be more than 10 pounds under your mount's rated capacity.  And the difference?......A cross between WOW and Holy......!

 

So I love my 6" refractor.  I love the beautiful stars.  I find the claims of increased contrast considerably overstated in most cases but it puts up a beautiful image nonetheless..   But even we besotted refractor lovers cannot ignore physics. 

 

As you have said, you are fairly new to the hobby.  You owe yourself a larger aperture scope at some point.  I am sticking with the one you mentioned and ignoring the other choices.

 

Now I've done it.  Hey everyone.  Remember I said I love my refractors?  I do.  And if you get either of the two you seem to have landed on you will be getting what many people would call a "dream scope".  But before you pull the trigger, look through a really good 9.25 with a good diagonal and wide EP.  You might be surprised. 


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#12 5th Gin

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Posted 27 July 2021 - 02:12 AM

I know this is the refractor forum.  I love refractors.   I own about 9 or so of them including some in the size range your are considering.  But I could not let the above go without a bit of a reality check.

 

I will just speak about the 9.25. 

 

You mention that it is "too long for DSO's"  I respectfully disagree.  With the correct EP's it offers spectacular views of deep space objects.  Far superior light gathering to your proposed 6".  They are not even in the same class.  Add to it a F6.3 reducer and the difference is even more stark putting the focal length not too far off of that of your 150 refractor while even faster.  (1480mm versus 1200.)    The 9.25's have a real cult following and I can personally attest to the fact that for deep space objects it usually just blows away my 6" refractor.  My former copy had wonderful optics.    Even my 8" SCT is quite capable of embarrassing my good 150 refractor.  The 9.25 weighs just a hair less than the 150 you propose but it is much shorter and therefor much easier on your mount.  And likely to be noticeably more stable.  Simply put, you will just see a whole lot more through a 9.25" scope than you will through a 6" one.

 

I wish to join those who might say that while a 150 F-8 will definitely be an improvement over a 115 F/7, it will not be a real game changer except on some very specific objects.  You will notice a difference but nothing like what you would see with an 8" not to mention a 9.25" scope.  And for only 7 pounds more on your mount you could go to an 11" SCT and still be more than 10 pounds under your mount's rated capacity.  And the difference?......A cross between WOW and Holy......!

 

So I love my 6" refractor.  I love the beautiful stars.  I find the claims of increased contrast considerably overstated in most cases but it puts up a beautiful image nonetheless..   But even we besotted refractor lovers cannot ignore physics. 

 

As you have said, you are fairly new to the hobby.  You owe yourself a larger aperture scope at some point.  I am sticking with the one you mentioned and ignoring the other choices.

 

Now I've done it.  Hey everyone.  Remember I said I love my refractors?  I do.  And if you get either of the two you seem to have landed on you will be getting what many people would call a "dream scope".  But before you pull the trigger, look through a really good 9.25 with a good diagonal and wide EP.  You might be surprised. 

Those are very good points! And yeah the 9.25 is quite short and looking very interesting. I do have several questions tho.

  • What 0.63x reducer for the 9.25 will you recommend? I was using the official 0.7x reducer as a reference point and thus 1645mm, which seems too narrow for my 294M and just okay for my a7 (which might be of less use in the light polluted backyard). I have the 0.79x TS reducer so the 150 doublet will end up 948mm which is more manageable for DSOs based on my limited experience. But even with 0.63x it seems I'll need to stick to the AT115EDT for many objects (636mm after reducer), learn stitching (currently have no experience on this but interested), HyperStar (f/2 seems hard to manage and itself is very expensive), or upgrade to 268M etc (a full set of new filters/wheel etc is also needed).
  • For visual, what EPs would you recommend to couple with the 9.25 for the wider field?
  • You mentioned that the 8" SCT can outperform the 6" APO. I read somewhere a theory that due to the central obstruction and mirror reflectivity etc, the overall performance of the 8" is close to 203mm - 64mm = 139mm refractor. Do you think that applies?
  • Can the CEM40 mount actually support the 11" and imaging train? Sounds risky but yeah the same applies to the long 150 doublet. Only the 140 and the 9.25 seems safe on it. I'm also checking mounts like CEM70 as I like the lightweight CEM/GEM series. Wondering if there are other good alternatives.

Edited by 5th Gin, 27 July 2021 - 02:26 AM.

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#13 Rasfahan

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Posted 27 July 2021 - 02:46 AM

I believe dnrmilspec referred to visual use only, I can not comment on that, since I prefer Newtonians for ease of collimation.

 

I‘ve seen many images from standard SCTs and EdgeHDs with reducers, and I felt they always show significant off-axis aberrations, especially CA. This will be a lot better in a refractor (or a non-reduced EdgeHD, or a corrected RC if you‘re up to a challenge). 

 

I have not seen any raw data on either refractor in this thread. I‘ve scoured astrobin, but the stars in the images are always very much processed, so it is difficult to judge color correction. If anyone can give me a pointer to raw data, I‘ld be very interested. 

 

I do not know the CEM40 myself, but the 6“ doublet is a very long scope, I can not imagine that this will work well. Concerning FL and DSOs, I think I have been quite successful at FLs of 1600 and 2000mm. The targets are not the bigger emission nebulae but either small nebulae or far away galaxies. There are an awful lot of them. The difficulty and mounting requirements are high, no comparison to the 4“ Esprit.

Personally, I think if you are looking at FLs of 900-1200mm, a good refractor is a very nice instrument. If you are willing to put in some more work, and have the space and mount for it, a well-corrected imaging Newtonian could give you a much faster scope, which might be useful in LP. 


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#14 alphacentauri

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Posted 27 July 2021 - 03:21 AM

@ 5th gin

 

here the link from Astronomie.de

https://forum.astron...bjektiv.309935/

 

Michael


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#15 Jon_Doh

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Posted 27 July 2021 - 08:26 AM

 

Those are very good points! And yeah the 9.25 is quite short and looking very interesting. I do have several questions tho.

  • What 0.63x reducer for the 9.25 will you recommend? I was using the official 0.7x reducer as a reference point and thus 1645mm, which seems too narrow for my 294M and just okay for my a7 (which might be of less use in the light polluted backyard). I have the 0.79x TS reducer so the 150 doublet will end up 948mm which is more manageable for DSOs based on my limited experience. But even with 0.63x it seems I'll need to stick to the AT115EDT for many objects (636mm after reducer), learn stitching (currently have no experience on this but interested), HyperStar (f/2 seems hard to manage and itself is very expensive), or upgrade to 268M etc (a full set of new filters/wheel etc is also needed).
  • For visual, what EPs would you recommend to couple with the 9.25 for the wider field?
  • You mentioned that the 8" SCT can outperform the 6" APO. I read somewhere a theory that due to the central obstruction and mirror reflectivity etc, the overall performance of the 8" is close to 203mm - 64mm = 139mm refractor. Do you think that applies?
  • Can the CEM40 mount actually support the 11" and imaging train? Sounds risky but yeah the same applies to the long 150 doublet. Only the 140 and the 9.25 seems safe on it. I'm also checking mounts like CEM70 as I like the lightweight CEM/GEM series. Wondering if there are other good alternatives.

 

I actually owned an 8" SCT and a 6" refractor at the same time and I set them up side by side in my drive one night.  The 6" on some things did out perform the SCT, but on the moon and globs the SCT spanked the refractor.  Some things showed about the same.  I thought Saturn was far better in the SCT too, but Jupiter was about the same to my eyes.

 

As for which 140 and 152 I was referring to, the 140 was a TEC and the 152 was a TAK - both triplets.  I know we're talking about doublets here, but the comparison was about how much the additional aperture would help and I was told it was a minor difference and not enough to justify going to the bigger tube.  Again, I didn't see for myself but was speaking to someone who had gone through the same exercise of deciding between a 140 and 152 and had looked through both scopes.  

 

Having owned an SCT I like the suggestion of considering a 9.25.  It will really show you a lot.  I had a 6.3 reducer that I kept on mine all the time.  I really regret selling it, but I was accumulating too much stuff and something needed to go.  I now think I chose poorly in letting my SCT go.


Edited by Jon_Doh, 27 July 2021 - 08:34 AM.

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#16 dnrmilspec

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Posted 27 July 2021 - 09:08 AM

I don't usually get into astrophotography questions because there are a great many folks here far better qualified than I am to answer them.  I was speaking primarily of visual use.  Nevertheless. 

 

In general I think you are considering two scopes that are not really very significant "upgrades" from what you have.  Indeed they are both doublets and I will leave it to others who know the scopes better than I to discuss their color correction compared to what you have.  My suspicion is that they may not be significantly better if they are better at all for AP.

 

The 9.25 with Hyperstar is a different thing altogether.  I have found Hyperstar to be easy to use and a real game changer.  (Mine with an 8")  The 9.25" scope has a smaller secondary than Celestron's other SCTs which is good but with the Hyperstar installed you now have a comma free, flat field of 3 degrees.  525mm F2.2!!  With the standard 9.25 (not edge) and Hyperstar you are still cheaper than either scope you are considering with the FF. 

 

What EP for visual with the 9.25?  The 31 Nagler, of course.  wink.gif  Seriously though, judging from your sig, you will want some much wider EPs.  I won't hijack this thread by getting into the weeds with that but unless you have a few EPs you are not listing, for visual, you might consider some EP upgrades before you buy a new scope. 

 

I have seen the stuff about central obstruction for a long time.  I do not give it much thought.  Playing with math for visual is not very productive.  Be careful of things like "at the same magnification".  Depending on seeing I am not going to use "the same magnification" with my smaller scope than I can with my larger ones.  Contrast?  Well.  What diagonal are you using?  What eyepieces?  How is the seeing?  How sturdy is the mount?  How carefully are your scopes collimated?  There are far to many variables for the usual generalities to make much difference.  The other night I looked at Jupiter through the 6" frac.  Nice.  Then through the 10" SCT.   Nicer.  I could push the SCT much harder on that particular night.  Our results will always vary. 

 

Just to summarize my personal opinion.  I don't think you are looking at a significant enough upgrade to justify $3K on the two tubes you are considering.  Indeed if these doublets are upgrades at all for either visual or AP.  Your mount is very nice and capable of handling the large SCT quite well IMO.  Certainly with Hyperstar.   I don't know about the heavier fracs.  So maybe the best thing to do for now is to score an 8 - 10" dob for visual and continue to hone your AP skills. I am not being factitious.  I do not think you have articulated what it is that your triplet is not doing that you think either of these doublets will do. 


Edited by dnrmilspec, 28 July 2021 - 08:24 AM.

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#17 Jeff B

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Posted 27 July 2021 - 02:04 PM

Oh why is it directly bino-friendly more than the APM?

A standard 2" mirror diagonal has ~105mm of light path.  A typical bino viewer has ~115mm of light path so the combination needs ~220mm of back focus.

 

The APM has ~180mm of back focus available.  At least 40mm more is needed with a 2" mirror diagonal.

 

The TS-150 doublet has 230mm when you remove the integral extension tube, leaving ~10mm or so to spare for variations in where various eyepiece pairs will focus.

 

So the TS is bino-friendly with a standard 2" diagonal and typical viewer.  The APM is not.

 

However......

 

The Baader BBHS T2 mirror diagonal has a 51mm optical path length.  This would leave enough back focus for many viewers, but not all.  See this thread, post numbers 1 and 4: 

 

https://www.cloudyni...y-measurements/

 

Jeff


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#18 Supernova74

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Posted 27 July 2021 - 02:14 PM

A standard 2" mirror diagonal has ~105mm of light path.  A typical bino viewer has ~115mm of light path so the combination needs ~220mm of back focus.

 

The APM has ~180mm of back focus available.  At least 40mm more is needed with a 2" mirror diagonal.

 

The TS-150 doublet has 230mm when you remove the integral extension tube, leaving ~10mm or so to spare for variations in where various eyepiece pairs will focus.

 

So the TS is bino-friendly with a standard 2" diagonal and typical viewer.  The APM is not.

 

However......

 

The Baader BBHS T2 mirror diagonal has a 51mm optical path length.  This would leave enough back focus for many viewers, but not all.  See this thread, post numbers 1 and 4: 

 

https://www.cloudyni...y-measurements/

 

Jeff

I’ve actually seen some amateurs cut down there rather expensive OTA a tad barbaric it seems to me,even more so if thay didn’t cut it straight lol.



#19 ris242

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Posted 27 July 2021 - 03:54 PM

forgetting the extra length / possible mounting issues

 

Speaking purely visually - the extra focal length of the 150 - with the same eyepiece - everything will be 20% bigger..........planets........the moon............knock yourself out.

 

Both scopes are beasts.



#20 Jeff B

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Posted 27 July 2021 - 05:35 PM

I’ve actually seen some amateurs cut down there rather expensive OTA a tad barbaric it seems to me,even more so if thay didn’t cut it straight lol.

This "barbarian" does that all the time, even with some vintage AP scopes.  But I'm pretty good at it.

 

I wish more "OEMs" had the capacity to be bino-friendly built in to some of their refractors or available by special order.  

 

Jeff

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#21 5th Gin

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Posted 28 July 2021 - 06:04 AM

I don't usually get into astrophotography questions because there are a great many folks here far better qualified than I am to answer them.  I was speaking primarily of visual use.  Nevertheless. 

 

In general I think you are considering two scopes that are not really very significant "upgrades" from what you have.  Indeed they are both doublets and I will leave it to others who know the scopes better than I to discuss their color correction compared to what you have.  My suspicion is that they may not be any better if they are better at all for AP.

 

The 9.25 with Hyperstar is a different thing altogether.  I have found Hyperstar to be easy to use and a real game changer.  (Mine with an 8")  The 9.25" scope has a smaller secondary than Celestron's other SCTs which is good but with the Hyperstar installed you now have a comma free, flat field of 3 degrees.  525mm F2.2!!  With the standard 9.25 (not edge) and Hyperstar you are still cheaper than either scope you are considering with the FF. 

 

What EP for visual with the 9.25?  The 31 Nagler, of course.  wink.gif  Seriously though, judging from your sig, you will want some much wider EPs.  I won't hijack this thread by getting into the weeds with that but unless you have a few EPs you are not listing, for visual, you might consider some EP upgrades before you buy a new scope. 

 

I have seen the stuff about central obstruction for a long time.  I do not give it much thought.  Playing with math for visual is not very productive.  Be careful of things like "at the same magnification".  Depending on seeing I am not going to use "the same magnification" with my smaller scope than I can with my larger ones.  Contrast?  Well.  What diagonal are you using?  What eyepieces?  How is the seeing?  How sturdy is the mount?  How carefully are your scopes collimated?  There are far to many variables for the usual generalities to make much difference.  The other night I looked at Jupiter through the 6" frac.  Nice.  Then through the 10" SCT.   Nicer.  I could push the SCT much harder on that particular night.  Our results will always vary. 

 

Just to summarize my personal opinion.  I don't think you are looking at a significant enough upgrade to justify $3K on the two tubes you are considering.  Indeed if these doublets are upgrades at all for either visual or AP.  Your mount is very nice and capable of handling the large SCT quite well IMO.  Certainly with Hyperstar.   I don't know about the heavier fracs.  So maybe the best thing to do for now is to score an 8 - 10" dob for visual and continue to hone your AP skills. I am not being factitious.  I do not think you have articulated what it is that your triplet is not doing that you think either of these doublets will do. 

Regarding HyperStar, some of my concerns have been the focus accuracy/focus plane tilt required at the speed, the need to install/remove it back and forth and re-collimate, and the limited image circle (also for the 0.63x reducer). Further insights on those are much appreciated.

 

More importantly, playing with Stellarium I just can't figure out how to frame many objects without serious mosaic or cropping with the SCT: there is a large gap between f/2 and f/6.3. But inspired by your and Rasfahan's suggestions, I take a second look on Newtonians and found the 10" f/4 to be just about right for the majority of interested objects. Correct me if wrong but I think I can also emulate the long focal length SCT with the high MP mode on 294M, narrow eyepieces, or Powermates, while the other way around is harder. I did get upsold to the TS ONTC version, which is also quite expensive so a hard decision to make.

 

To clarify, I'm not replacing the 115mm triplet, so it doesn't have to be a large "upgrade". I simply want something to look at when the other scope is imaging, or get two cameras to work at the same time, either for the same field or not.



#22 5th Gin

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Posted 28 July 2021 - 06:13 AM

I think I've narrowed down to mounting requirements of APM 140, TS 150, or TS 10" f/4 ONTC Newtonian. The largest to ride properly on the CEM40 wins the deal. (Why not 8" Newtonian? Because I want a significant advantage over the refractors to justify the collimation, diffraction spikes, smaller image circle, and maybe wind, cooling etc)

 

To play safe it would obviously be the APM, but maybe it's time to challenge the mount. There are certainly many people that tried this, or on AZ-EQ6.


Edited by 5th Gin, 28 July 2021 - 06:43 PM.


#23 Jon_Doh

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Posted 28 July 2021 - 08:34 AM

I use Orion's version of the AZ-EQ5 in AZ mode and it does fine.  But, if you ever get the fever and decide you want/need a 152 or a 9.25 SCT you'd be better served investing in the AZ-EQ6 as it can handle all the scopes we've talked about.



#24 Supernova74

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Posted 28 July 2021 - 10:57 AM

Well if I was on the opposite side of fence choosing between the two?

i would have to decide where my main interests lay in either planetary or deep sky observing visually i would prefer the 150 mm refractor however not exsactly fast of being a f8 scope which the 140mm would be preferable for overall versatility in being more ideal for both visual and imaging.regardless of the minuscule aperture gain would be hardly noticeable.


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#25 5th Gin

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Posted 28 July 2021 - 05:27 PM

I use Orion's version of the AZ-EQ5 in AZ mode and it does fine.  But, if you ever get the fever and decide you want/need a 152 or a 9.25 SCT you'd be better served investing in the AZ-EQ6 as it can handle all the scopes we've talked about.

You mean APM 140 on AZ-EQ5? Does it support long exposures well? I think CEM40 is actually in the class of EQ6, so if EQ5 supports 140 well CEM40 should support 150 well also.




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