50 replies to this topic

[C0rs4ir_]

Hi,

I have the Tak, its great so far and im using it just for visual solar system objects. My impression is that its running out of light before running out of details it can show with magnification. Therefore im thinking of a bit more aperture.

 

Would the APM 140mm ed f/7 scope (https://www.apm-tele...-f7-with-25-zta) be a worthy upgrade for the tak or is it wasted money when it comes to visual use on moon and planets compared to the 100mm DZ? Seeing should be ignored in this question.

 

Thanks for your thoughts.

Edited by C0rs4ir_, 16 September 2024 - 03:53 AM.

[Spikey131]

The 140mm refractor will show noticeably more detail on the moon, Jupiter, Saturn and Mars.  DSOs will also be more impressive.

 

The 140 requires a heavier mount.

[Stellar1]

From a 100 to a 140 is a huge jump in aperture and will certainly be an upgrade, the Tak os a great scope but it doesn’t defy the laws of physics. Going up to a great scope like the APM will be a very noticeable difference at the eyepiece I don’t care how good a 100mm is. Short answer is yes, it is worth the upgrade.

[Bearcub]

Why not 152mm? I bought it last month and i checked today on their website, they still have decent 500eur discount. Ofc its f/6, so really fast telescope and pricier. I wrote blog style, long review and comparison between my dob.. but when it comes to refractors i have no experience. I have only one refractor.

[C0rs4ir_]

Why not 152mm? I bought it last month and i checked today on their website, they still have decent 500eur discount. Ofc its f/6, so really fast telescope and pricier. I wrote blog style, long review and comparison between my dob.. but when it comes to refractors i have no experience. I have only one refractor.

I was looking at the f/6 scope, but i think for my high magnification planetary wishes it is not the tool of choice for me. It sounds like a good scope for medium magnifications though. Im coming from a f/8 fluorite doublet, so im already a bit spoiled there when it comes to color correction etc.

Edited by C0rs4ir_, 16 September 2024 - 06:59 AM.

[bobhen]

HERE is a link to a review between a Tak FS 128 and the APM 140. Scroll down to the section on Lunar and Planetary Observing. In the summary, the author wrote... Its (APM 140) "ultimate optical quality falls a bit short" of the world-class Takahashi fluorites ( FS 128) in contrast and snap-to-focus...

 

HERE is a link to a CN thread titled: Takahashi "TSA-120" vs "APM 140mm" vs APM 150mm f6 for visual. You might want to read that and get an idea if the APM 140 would be a better move for your lunar/planetary needs or more of a sideways move.

 

I would suggest if you want more lunar and planetary detail and you want to stay in the refractor world, I would first consider something from a high-end maker and something like a Takahashi TOA 130. Or an APM LZOS 130F9.2 if you can get one. 

 

If your budget only allows for an APM 140 F7, you might consider the TS-Optics CF-APO 130 mm f/7 FPL55 Triplet APO. A 140 mm F7 doublet is pushing things optically compared to a 130mm F7 triplet. And for lunar/planetary, you want to consider optical quality over a slight increase in aperture. That slight increase in aperture will not buy you any more detail if the optics are not up to the task.

 

Good luck

 

Bob

[C0rs4ir_]

Thanks Bob, thats exactly what i thought.. The aperture gain of the apm 140 might not outdo a TSA 120 for these targets.

In this category you get what you pay for i assume.

Edited by C0rs4ir_, 16 September 2024 - 07:14 AM.

[Hans Joakim]

The TS 150 F/8 is priced very reasonably for the time being: https://www.teleskop...7-focuser-14789.

 

FPL53 + lanthanum and a very decent focuser, plus same reported weight as the APM. Does anyone know how this compares optically to e.g. the APM?

Edited by Hans Joakim, 16 September 2024 - 07:50 AM.

[Sacred Heart]

I was looking at the f/6 scope, but i think for my high magnification planetary wishes it is not the tool of choice for me. It sounds like a good scope for medium magnifications though. Im coming from a f/8 fluorite doublet, so im already a bit spoiled there when it comes to color correction etc.

Agema SD130 / 150, either scope should do it.  Fluorite doublet f8.  It will be expensive, and a wait for it.

 

My SD130 is my first fluorite, I'm impressed with it.   Visual so far, can't get past the eyepiece.

 

https://www.agemaopt...com/telescopes/

 

Joe

[Ihtegla Sar]

I went for a TEC 140FL when I wanted an aperture upgrade from my FC100DL. I was not dissapointed. But there is a significant price difference between a TEC 140 and the APM, not to mention the two year wait.

[C0rs4ir_]

I went for a TEC 140FL when I wanted an aperture upgrade from my FC100DL. I was not dissapointed. But there is a significant price difference between a TEC 140 and the APM, not to mention the two year wait.

US scopes are no option for me since import taxes would be too high, for my next buy i want to take that into account. But i agree, something good in the 130 or 140mm area would be a real upgrade indeed.

Edited by C0rs4ir_, 16 September 2024 - 09:26 AM.

[Ihtegla Sar]

US scopes are no option for me since import taxes would be too high, for my next buy i want to take that into account. But i agree, something good in the 130 or 140mm area would be a real upgrade indeed.

CFF?

EDIT: Well, they were in Europe, but now it looks like they just moved their operations to Australia. https://cfftelescopes.eu/updates

Edited by Ihtegla Sar, 16 September 2024 - 09:32 AM.

[Victor Martinez]

Hello,
In these same forums the AT 125 f7'8 doublet has been compared very favorably with the Taka FS 128. For practical purposes this AT is optically identical to the TS 125, with the difference that the TS mounts FPL53 glass. The TS 150 has the same optical design as its little brother, so its performance should be at an excellent level for its price, and very close to that of other refractors considered premium. You also have in Europe the Tecnosky 150 f8 OWL, which guarantees you an optical certificate with a minimum Strehl of 0.95.
https://www.youtube....h?v=C63QW5JtNWA

In the written version of the review it is compared to a FS 128

https://www.binomani...ky-owl-150-apo/

Edited by Victor Martinez, 16 September 2024 - 10:23 AM.

[Jon_Doh]

I have the APM 140 and a few years ago at one of our club events I asked a fellow member who had a Tak 100 set up nearby if I could take a peak.  He had it set on Jupiter and I was curious because I had heard so much about the Taks.  But having just viewed Jupiter in my 140 I was very disappointed in the Tak and wondered where the beef was.  The 140 showed so much more and to my eye had better contrast.  But no doubt because 40 extra mm is a whopping difference.  If you can find someone with the 140 look through it and decide for yourself.  Keep in mind too there are some reasonably priced triplets out there that might serve you well.  40mm is a huge upgrade to what you have.

[aa6ww]

Anything visually a TSA-120 can do, the APM 140 will do better. The TSA-120 is a great scope but its still 120mm of greatness, not 140mm of greatness.

If your mount can handle the 140, that is the better choice vs "ANY" 120.

 

 Ralph

 

 

 

Thanks Bob, thats exactly what i thought.. The aperture gain of the apm 140 might not outdo a TSA 120 for these targets.

In this category you get what you pay for i assume.

[betacygni]

I’d seriously look at the 150mm TS options (they have both an f8 doublet, as well as a more expensive triplet). While I don’t believe you mentioned your mount, the reason I say this is I suspect many mounts that will hold a 140mm will hold a 150mm, so might as well get the extra 10mm.

This is the main advantage of the TSA-120, it will ride on many smaller mounts that will support a 4” scope (so perhaps you won’t need to upgrade your current mount). That said, the jump from 100mm to 120mm is noticeable of course, but not massive.

Edited by betacygni, 16 September 2024 - 10:50 AM.

[Bearcub]

Hello,
In these same forums the AT 125 f7'8 doublet has been compared very favorably with the Taka FS 128. For practical purposes this AT is optically identical to the TS 125, with the difference that the TS mounts FPL53 glass. The TS 150 has the same optical design as its little brother, so its performance should be at an excellent level for its price, and very close to that of other refractors considered premium. You also have in Europe the Tecnosky 150 f8 OWL, which guarantees you an optical certificate with a minimum Strehl of 0.95.
https://www.youtube....h?v=C63QW5JtNWA

In the written version of the review it is compared to a FS 128

https://www.binomani...ky-owl-150-apo/

I saw that video with youtube captions.. it was hard to read, but this website version with translator is 100% better than youtube with captions!

[bobhen]

Anything visually a TSA-120 can do, the APM 140 will do better. The TSA-120 is a great scope but its still 120mm of greatness, not 140mm of greatness.

If your mount can handle the 140, that is the better choice vs "ANY" 120.

 

 Ralph

Remember, the poster is concerned with lunar and planetary observing only.

 

In the review I posted in my post number 6. The author compared a Tak FS-128 to the APM 140 on the moon and planets. After observing Jupiter in the 140 he wrote...Yet, somehow, the image was even better in the FS-128...The most elusive details seen with the APM were very similar in the Tak 128, but the cloud belts took on an “etched” appearance with somewhat better color saturation. 

 

The above sounds like the "smaller" Tak FS 128 was delivering a sharper view (more etched) with more contrast (better color saturation).

 

The 140 is a doublet, and a fast doublet for its size. I would not consider the APM's 140's optical quality to be "great" or in the same league as Tak's TSA slower triplet optics. 

 

On Mr Yoshida’s list of telescopes for planetary observing, he lists the Takahashi FS 128 and the Takahashi TSA 120 as exact equals. Therefore, one could logically expect the TSA 120 triplet to also deliver a Jupiter view that is also sharper or more etched and with more contrast or color saturation than the APM 140 –  just like the FS 128 did in the review.

 

Bob

[C0rs4ir_]

I’d seriously look at the 150mm TS options (they have both an f8 doublet, as well as a more expensive triplet). While I don’t believe you mentioned your mount, the reason I say this is I suspect many mounts that will hold a 140mm will hold a 150mm, so might as well get the extra 10mm.

This is the main advantage of the TSA-120, it will ride on many smaller mounts that will support a 4” scope (so perhaps you won’t need to upgrade your current mount). That said, the jump from 100mm to 120mm is noticeable of course, but not massive.

I thought about the 150mm f/8, but i think its not what im looking for optically and from a handling perspective. Atm im looking at a used TOA 130NS, not so huge, but can take some higher mags without the image collapsing. The apm 140 probably cant compete here. 130mm quality aperture is enough for me, for more aperture needs i still have my C9.25.

[C0rs4ir_]

I thank you all for the thoughts and input, i think as newbie i have a better orientation now with the apos.

[betacygni]

I thought about the 150mm f/8, but i think it’s not what im looking for optically and from a handling perspective. Atm im looking at a used TOA 130NS, not so huge, but can take some higher mags without the image collapsing. The apm 140 probably cant compete here. 130mm quality aperture is enough for me, for more aperture needs i still have my C9.25.

The TOA is a great scope no doubt, but don’t underestimate its weight/size, it’s significantly more than the aperture would suggest. Not even including rings the TOA-130 is heavier than the TS 150 doublet I believe.

Edited by betacygni, 16 September 2024 - 01:44 PM.

[25585]

US scopes are no option for me since import taxes would be too high, for my next buy i want to take that into account. But i agree, something good in the 130 or 140mm area would be a real upgrade indeed.

This scope is expensive but has good reviews. CN members do & have owned them.

 

https://www.apm-tele...r-1301200-37zta

[t.mihai147]

I have TAK FC100DC and APM140ED. I have compared them on Jupiter and Moon and I am always impressed by the contrast I have in TAK at 220x with TOE 3.3mm. If you want to have higher magnifications than you need a bigger aperture for sure.

 

Yes, the Jupiter image is dimmer than in the APM but I can see practically similar details. On Moon the APM is also very good, hard to see big difference except image brightness.

Now the reason might be the fact that my APM140 has obvious SA and this is impacting the details in the image so my own advice is try it before you buy it. The APM140 ED is designed such as in theory it can reach a max. Strehl of 0.93 while the Fluorite could be better but I do not have any data on its theoretical Strehl.

Better for me on Jupiter is a very good C9.25 that I own but it is very difficult to find a night when the image is not degraded by air turbulence for large aperture telescopes and/or tube currents.

[C0rs4ir_]

I have TAK FC100DC and APM140ED. I have compared them on Jupiter and Moon and I am always impressed by the contrast I have in TAK at 220x with TOE 3.3mm. If you want to have higher magnifications than you need a bigger aperture for sure.

 

Yes, the Jupiter image is dimmer than in the APM but I can see practically similar details. On Moon the APM is also very good, hard to see big difference except image brightness.

Now the reason might be the fact that my APM140 has obvious SA and this is impacting the details in the image so my own advice is try it before you buy it. The APM140 ED is designed such as in theory it can reach a max. Strehl of 0.93 while the Fluorite could be better but I do not have any data on its theoretical Strehl.

Better for me on Jupiter is a very good C9.25 that I own but it is very difficult to find a night when the image is not degraded by air turbulence for large aperture telescopes and/or tube currents.

Thanks, that was very helpful. I have indeed the impression that the Tak 100 is only limited by the brightness when i viewed the moon at ~300x (2" Baader BBHS mirror diagonal, Apm 2.7x barlow @2.4x, Greatstar ADC and Baader classic ortho 6mm). Details kept coming though absolutely clear (at least to my subjective impression).

So i might also think about a TSA 120. But the apm 140 i rule out more and more.

Strehl is not good at describing optical surface smoothness or contrast etc. so im not very fixated on it in this case.

Edited by C0rs4ir_, 17 September 2024 - 09:42 AM.

[aa6ww]

I sold my TOA-130 and bought an APM-152ED and never missed the Tak. The 152 is considerably lighter also. The added aperture makes "EVERYTHING" better.

I sold my TSA-102 for my SW-120ED and never missed the TSA-102 afterwards.

I think Takahashi's are the best we can get optically. Once the comparison isn't about the same aperture, the larger aperture wins optically, especially when both have premium glass.

Takahashi's triplets are superior when talking about AP. but visually, more aperture means more resolution. 

My friends APM-140SD will crush my 120SW in every way visually.

There is no way that "ANY" 120mm refractor will outperform the APM-140 on any visual test on Jupiter. The 20mm extra of the APM-140 will bring out more colors on Jupiter and more contrast and resolution.

My comments are based solely on experience at the eyepiece, not someone's biased opinion read in an article. 

 

- Ralph

 

 

 

 

 

Remember, the poster is concerned with lunar and planetary observing only.

 

In the review I posted in my post number 6. The author compared a Tak FS-128 to the APM 140 on the moon and planets. After observing Jupiter in the 140 he wrote...Yet, somehow, the image was even better in the FS-128...The most elusive details seen with the APM were very similar in the Tak 128, but the cloud belts took on an “etched” appearance with somewhat better color saturation. 

 

The above sounds like the "smaller" Tak FS 128 was delivering a sharper view (more etched) with more contrast (better color saturation).

 

The 140 is a doublet, and a fast doublet for its size. I would not consider the APM's 140's optical quality to be "great" or in the same league as Tak's TSA slower triplet optics. 

 

On Mr Yoshida’s list of telescopes for planetary observing, he lists the Takahashi FS 128 and the Takahashi TSA 120 as exact equals. Therefore, one could logically expect the TSA 120 triplet to also deliver a Jupiter view that is also sharper or more etched and with more contrast or color saturation than the APM 140 –  just like the FS 128 did in the review.

 

Bob