Marian M

Hi friends!

End of the story (at least for the moment)- after a disappointing experience with a new APM 100 SD 90 degrees, I decided to go with an used Omegon Brightsky true binocular (achro, 70mm, 45 degrees) and a branded new TS doublet FPL53

Extremely happy with the Omegon true binocular, at low/ low-medium power, through binocular summation factor, shows the same as my 102 with bino, but has the advantage of going to lower power and easier to setup. For medium to high/ high power, for sure 102 is better. I went to observations already many times with it, it is phenomenal with Morpheus 17.5 and 9, probably I should add to my collection the Morpheus 12 as well. Also very nice with APM 24 UFF. It is very natural and easy to setup with a phot tripod and video head. Even if it is an achro, stars looks great, without annoying chromatic aberration. During daylights, the colors are there, but image is very bright and sharp for an achro.

The TS 125 just come and I have to test it more times, so far the weather was bad here. It came extremely well collimated from TS (great services from them!) and, at first sight, seems closer to 150 vs 102, where I did some comparisons, as overall planetary performance. Surprisingly, on a short comparison with 120ED SW, the 0.5cm more shows a little bit more- some stars close to Polaris where a little easier to be seen than with 120.

Wish you clear sky!

Forgot to add, same magnification and similar eyepieces

Hi friends!

Trying to resurrect this topic, I found that there is another option for a RFT- APM 100mm ED 90 deg binocular. Many thanks @The60mmKid for the idea, somehow I did not pay the proper attentions from the beginning.

From binocular summation theory could be similar with an 140 refractor with binoviewer, or more. I had the chance to look through an Omegon 100mm 90 deg binocular today with 9mm Morpheus (around 60x magnification), but plenty of colors. I presume this one is the same with APM SA (plain achro), so the APM ED should be better. Attaching here a picture with my hand held phone.

• Second image, for the sake of comparison, is another building with high black/ white contrast,  same eyepiece but 120/600 achro, full of colors but maybe better.

Just wondering if someone here had the chance to compare a larger refractor with binoviewer with a true binocular

Thank you!

On 26/08/2023 at 15:47, Paz said:

The SM125mm does go deeper than the 102mm refractor on DSOs. I didn't measure it empirically but I would describe the improvement as obvious but not epic. I think a bigger jump in aperture would be necessary for the difference to be epic.

I also have the 120/600 f5 achromat and still use it from time to time but I use the 102mm f7 more because the quality-to-effort ratio is better and because the 102mm f7 is a more general purpose scope. I found the 120/600 does better on dark extended objects at low magnifications, but on less extended targets, and targets that resolve into stars and bright targets and as magnigication goes up the 102edr catches up and pulls ahead.

I haven't looked through a 152mm achromat to be able to compare it to a 125mm apochromat. If weight is not an issue and only observing DSOs at low magnifications is the task then it sounds like a bit of a conundrum as to which to go for.

One thing I would say is to check if the 152mm can use binoviewers without having to barlow it.  You can shorten the ota on the TS Optics125mm scope for binoviewing at low magnifications, but if the 152mm has to have some barlowing, then you may find that (for binoviewing at least) you can't get the lowest magnifications in the 152mm scope.

It's difficult as all those scopes are good for their design purposes, it's just making choices about which compromises you give and take on.

Many thanks for the quick revert!

I had a quick session of observations last weekend where I had the chance to compare my 102 TS FPL53 with my SW120/600 achro. Most time spent on Double Cluster and Moon, with my binoviewer eyepieces- having 2 of each, I just dropped them in the 2 scopes, a little bigger magnification on 102 because of the longer F (714 vs 600).  On Double cluster, up 67x (Morpheus 9), the image was brighter in achro, but the same was visible in apo as well, just a little more darker. Any single star I tried to look for in achro, was visible also in apo. Above this magnification (using some barlows and GPCs), the image started to break down in achro. Probably above this magnification, it was the other way around- any star visible in apo, if you know where to look for, was visible in achro as well. I am not an experienced person and most of my time I spent enjoying what I see and less comparing, but most likely a more experienced person would have seen probably a bigger difference. Also between 60x- and probably 120x, the image in achro was reminding me my already sold Mak127 view, the stars weren't single points like in apo but much more "unfocused" with "a visible diameter" 

Regarding the TS 152 5.9 achro, TS give very clear data on backfocus. It has a slightly bigger backfocus from 2" thread compared with my 102 apo, which I have adapted for bino without ang GPC. By removing the M68 to 2" adapter and replacing with the short M68 to T2 adapter, about 25 mm will be gained, which will increase the backfocus bigger than 150mm requested (110mm for MB2 and 40 mm for T2 Baader prism)

Now coming back to 125 APO, still I am trying to read as much as possible here. The quality seems very good (very happy with the smaller brother, 102), it will take the binoviewer without any other change, directly with the 2" diagonal, which also will shorten the length and do it much solid and rigid. Probably up to 60x-100x, the 152 will be above or similar, while above this magnification, 125 will start shining- talking here about DSO only, for the rest, 125 will outperform

Which one to take, I yet have to figure out, think, debate...

Many thanks again!

On 17/08/2023 at 01:13, Paz said:

I have had a couple of goes out in the field, I can share some feedback from those.

Nightime Session SM125 and Altair Starwave 102EDR

I picked out the 102EDR to compare it with, the point being to see if the SM125 behaves like a good quality refractor, I was therefore looking for the benefits (and drawbacks) of more aperture but whilst maintaining the same good quality refractor like views. I was mostly comparing the SM125 at 216x (Baader T2 prism diagonal, 4.5mm Delos) with the 102EDR at 204x (Tak prism diagonal, 3.5mm Delos). It was difficult to match magnifications exactly, this was the closest I could get, but it allowed me to be able to observe and compare going back and forth from one eyepiece to the other with no delay.

Epsilon Lyra 1 - This target was 77 degrees up and very good seeing. My notes on the SM125 were "...looks good, super clean, first rings mostly intact, big clear split, the gap between the inner edges of the airy disks is about the same distance as the diameter of an airy disk, could be the best split I've seen...". That's what I said in my dictaphone but I think on reflection my 14" reflector will have done better, I just would not remember enough detail without checking old observing notes and that is a completely different scope anyway. The 102EDR showed a good view also and a clear / clean split, but the gap between the airy disks was smaller in proportion to the size of the airy disks, as would be expected. The first rings looked slightly more complete/intact in the 102EDR but I only noticed this because I was looking specifically for things like this.

M13 - I used the same sets ups as for Epsilon Lyra above and M13 was about 65 degrees up and quite good seeing. The SM125 was went deeper, resolved more, and presented more extension of the object, but maintaining the same refractor type of the view. There was a very thin veil of turbulence from quite nearby houses that was visible in both scopes if I concentrated on it, but it was easier to see in the SM125.

Zeta Hercules - I've read about this one but I don't think I've had a go at it myself before. It was about 56 degrees up, I didn't state the seeing but it must have been pretty good given the results. I used the same set ups as above again, and then tried the 3.5mm Delos in the SM125 taking that up to 279x. Starting with the 102EDR this time (at 204x) my notes were "...definitely no split, maybe slight thickening of the diffraction ring at 2 o'clock...". However it turns out that thickening was the secondary so I think it can be called a split - it was better than a peanut or a bar. In the SM125 at 216x my notes were "...tighter airy disk, almost a split, clear blob on 1st diffraction ring closer to 1.30 o'clock..."., i.e. an improvement on the 102EDR at similar magnification, then at 279x in the SM125 my notes were "...clear knobble at 1.30 o'clock on 1st diffraction ring...". So both scopes were a win, but the SM125 was better due to having more aperture. Checking Sky Safari later the secondary was at position angle 88 degrees and just eyeballing the screen from my perspective it was at 1.30 o'clock, Although it was tougher, I am sure I would have pinned the position angle down just as accurately in the 102EDR if I had observed in that scope for longer.

Albireo - I did not compare scopes on this one, I just had a look at 279x with the SM125, Albireo being about 65 degrees up and good seeing. My notes were "...huge split, clean airy disks, almost intact rings, bright orange, smaller blue...". I would not usually look at Albireo at that magnification hence the comment that the split looked huge, but it was a fine view.

I had left both scopes out to cool for a while and the temperature was not very low so there were not the right circumstances to test for differences in cool down. I can say though when taking it down the OTA felt warm to the touch kind of like plastic would, I think this will be a bonus in the winter compared to handling a freezing cold metal tube, I didn't have any problems with vibes, the SM125 works fine on an EQ5, although I might raise the legs a bit for a little more height, as I only had the legs a little over half extended. The focuser did fine, collimation looked straight at various altitudes and rotations, but it has not yet been tested in the field with a heavy 2" eyepiece or binoviewers loaded with heavy eyepieces. I think I might want to get a longer dovetail bar for a bit more balancing range to cover light to heavy loads at the focuser, but I will keep going and see if I can cover the bases as it is, it might be a close call. 

Solar Observing - SM125 Only

Solar - The SM125 has enough in focus for me to use the same set up that I use on my ED102R which is good and as I hoped/expected. With Binoviewers and a wedge in green light (30mm NPL's + 2.6x GPC so about 85x) I can tell that the SM125 shows more detail than the 102EDR, for example looking at the stippling all over the face and the faculae around AR3394. The SM125 also shows up the seeing conditions more, the seeing was not great and this was more evident. I did not test it back to back with the 102EDR but white light solar with the 102EDR is what I am most current/familiar with and so I am confident about the comparison. I think the SM125 presents a similar nature refractor view to the 102EDR but resolving more as one would expect from more aperture. The detail/resolving of the sun from the SM125 is I think closer to a C8, but how close would require back to back testing with the C8 which I am not so familiar with when it comes to white light observing, However I can say that when solar observing with the C8 that presents details more softly and it shows up any seeing issues more,

A bright planet the moon are the other things I would like to try to cover most of the bases, and testing it with something heavier in the focuser, but fundamentally it seems to be a good quality 5" refractor that's light enough for me to handle happily. I did some star testing on Deneb and Vega but interpreting and reporting on those is beyond what I feel able to remark on, but I am happy with my notes above being fair comment.

Paz, very nice and detailed reading!

How would you rate the 125 apo vs 102 apo on DSO only, is the light gathering substantial, it handles magnification better, what about the real resolution? Does it worth?

I have the TS 102 FPL53 and 120/600 achro, bino-addicted. Being a refractor only person, I am planning to increase the aperture for DSO only, for magnification up to 100x. The 152 f5.9 achro (TS, Tecnosky) has been my first option but many people, including my star parties budy, are pushing towards 125 FPL53- being the max I can afford. Weight, mount, rest I know and I can handle..

DSO only, up to 100x, would 125 be a better option? Or 152 achro, if by chance, you have ever compared. Sorry to jeopardize the thread..

Thanks a lot!

On 01/04/2023 at 13:24, bosun21 said:

This is no good for an EQ mount as the angle of the eyepiece is constantly changing depending on where your target is in the sky. Hence the clicklock.

Yes, this is true

This is why I much prefer the AltAz mounts 😀

Hi Don!

Both- if time and AltAz position of the scope allows, I am sitting on the chair, if not/ available time is short, standing

Thanks a lot for your message, I forgot to add that a chair will make the difference. On the shopping list, there is a chair with many locking heights, instead of the current one with 2 only

3 minutes ago, John said:

I'm not sure if that is the case in all countries though 🤔

Smaller the country, lesser options. But there are many more branded new options 😀

5 minutes ago, John said:

Over the years I have been on forums such as SGL and CN I have noticed that there are very many differences in preferences when selecting and using eyepieces - one persons dream eyepiece can be another persons nightmare. That may explain why there are often sharp differences of opinion on eyepieces as well, perhaps more so than other items of astronomical equipment !

I have learned the hard way the same. Before my above experience , I bought XWA 10mm, one the the most praised eyepiece on comfort and quality. I wasn't able at all to accommodate, even with the eyecup up (too far to "touch" me), so I sold it... After that Morpheus come, now seems redundant to buy again the XWA 10, owning Morphues 9, but who knows 😄

For all the people here, who want to buy expensive eyepieces or telescopes (better to say designs)- please wait, put some effort to go and test it, wait, test, wait, test. Otherwise the biggest joy of a new acquisition may turn on a big disappointment

Read, test, think (adjust expectations/ need), wait (clean your mind), buy... 😀 

On thought on eye placement on Morpheus line:

I faced the same in the past- being used with SLVs, Lacerta ED, where I was used to touch something with my face for the optimum position, it was a disaster when I have tried first time Morpheus eyepieces. Instead of observing, my whole attention was towards the eye placement, which I found very challenging. 

What I have been learned by my budy, was just to support my body on something, to lean on something- either the mount if allows, or on a chair for observation. Having this second contact point, it will keep the body/ head/ eye much better in the best position. You can try first during the day, when everything is easier on placement. You can learn your body on the same using binoviewer, because the effort is less while placing both eyes at once. Third, you can learn during the night. Sometimes, even today, there are moments when the eye placement is difficult for me during the night, but I must come very easy, slow, towards the eyepiece. With the SLV for example, with the eyecup up completely, you may just "jump" on the eyepiece, and is good to go. I have tried in the past with eyecup extension but it was (for me) the wrong way.

Why so much effort?  While removing the eyecup, the feeling of immersion is much better than with the eyecup there. For me, through the binoviewer, there is no comparison at all. Nothing similar. Huge difference... While scanning the Milky Way, through binoviewer, is like there is nothing between you and the sky. It is not like you are scanning the sky from ISS. It is like you are in the sky, surrounded by stars. Together with the quality of the eyepiece, this should be the reason of so many people here loving the Morpheus line, and so many association between immersion and Morpheus.

Forgot to mention, you should have no lights around you, no lights close to you, because the eyes are at some distance vs the eyepieces and any light will interfere.

Apologies if this has been approached earlier in this thread- I didn't read it from the beginning

My today choices are:

Morpheus 17.5. I am using it in MB2 binoviewer, with eyecups removed, should I count it twice? 😄 This is my most used eyepiece today, together with the 2 Baader GPCs and the ED comma corrector from APM, there are plenty of variations in the magnification

Morpheus 9, same usage, more magnification; no eyecup for the most immersive experience 

APM XWA 13

APM XWA 7

The 5th most beloved eyepiece, should be either APM XWA 20mm, or APM UFF 30mm- both are on the wishlist; or APM XWA 5mm, who knows?

I am planning to buy soon the below bag:

Teleskop-Express: Geoptik Elephant Outdoor Case with cubed foam 57x44x22 cm

It is expensive but will keep all eyepieces safe and in a controlled environment. Such nice eyepieces deserve the best 😄. There are other sizes as well. Specific to me, I would like to buy the whole APM XWA range and to store them standing.

While going to observation, I will take some of the eyepieces in a smaller bag

Hi friends!

Just came back from a short trip in the mountains, where I took for the first time the 72 APO.

The sky was pretty black but not 100% transparent; I wasn’t very inspired and took with me only 2 eyepieces, Lacerta 30mm ED (which was useless, too much light, sky not absolute black) and the APM XWA 13mm (the only one used, in fact).

The 72 APO was riding the Benro tripod and S8 video head (overmounted), and, as expected, very stable (at least for a video head)

I have observed few DSO and the Moon. The Moon was rising after the firs forest, incredible experience to see the craters between the twigs of the trees. This reminded me from my youth when I saw the same through a Russian binocular, amazing experience, with so many craters appearing and disappearing in seconds behind the trees, it is that magic moment when you see our planet, with all of the beings, being part of the whole universe.

I spent more time on M57. While being frustrated that I was not able to see anything at all from the city, here it was very easy. The classic donut unfocused was extremely easy to see, direct vision. Close to M57, there are 3 collinear stars, from 10 to 11 magnitude, which were visible, mostly indirect vision. The max magnitude for this scope from what I found on internet is around 11, hence I presume a more experienced person/ maybe a better sky could have led to even 11.5 to be visible

Next was Double cluster. While form the city was barely visible, here I had that magic feeling of diamonds on the black sky. Even if there are only 72mm, the dark sky has pointed out the magic of the double cluster. The best Double cluster I have seen was through my classic 120/600 achro with 13 APM XWA. Despite the much smaller aperture, the 72 did properly his job.

Next was Wild Duck. Very few stars were visible, together with the foggy shape behind. I went to M13, which was just a small dust in the sky. I am 100% sure that a smaller focal eyepiece would have pop out few stars, will try next time. Last M10 and Lagoon Nebula, easy visible and nice but without any other details. Before going to bed, I had a look to Saturn- very nice ring but too less power for any other details.

A lot of fun, easy logistics and sharp view for a small telescope!

On 30/07/2023 at 02:51, Louis D said:

Here's a composite of the KUO 152mm Achromat with no filtering and 8 filter variations to try to both cut violet and sometime red fringing in an effort to increase sharpness and contrast:

The SemiApo is the Baader SemiAPO filter in 2" format.

It's too bad the Hirsch filters are only available used because they had a bunch of unusual colors such as their Light Yellow #12A (Wratten #4) and Light Blue #82B (Light Cyan).

The Green X1 (Wratten #11) and Yellow K2 (Wratten #8) filters are both 48mm Rokunar photographic filters.  Both are still available as new old stock on ebay in 48mm size.

The Cheap Yellow and Green filters came in a set of 6 colors from China for $13.  They tend to cause a bit of light scatter and loss of image fidelity.

The 600nm Shortpass filter (Minus-Red) is an uncut dielectric filter from China.

As in my previous post, the Baader SemiAPO does a very good job at cutting most of the objectionable violet fringing while avoiding adding a harsh yellow cast.

The Hirsch #12A does a good job cutting violet while adding very little yellow cast to the image.

The Yellow K2 is a bit heavy handed.  However, it cuts all but a tiny bit of violet fringing.  I should try pairing it with my 48mm Moon & Sky Glow filter to make a poor man's Baader Contrast Booster and reduce the yellow cast.

The Green X1 is a good compromise to cut both violet and red at a reasonable cost.

The Yellow/Cyan and Yellow/Minus-Red filter combinations do a bit better than the Green X1 by having higher transmission over a broader passband while still cutting almost all violet and red fringing.  However, the components are difficult to find.

Dear @Louis D,

Many many thanks for your time and patience to come back with so many details. It is very visible that there is no comparison between the 152 and the APOs or the Newton. I have compared directly my 102 APO with the 120/600 achro on Moon and, in fact, there is no comparison. Despite the fac that I have few instruments and eyepieces, you make me curious reading about filters- so far I don’t have any filter in my collection

Would help if, at some point of time, you succeed to compare the 2- Newton and 152 achro, for some DSO at different magnifications. At least in theory the 152 should provide better and more pleasant views up to 50x (if DSO is not so shiny- I read somewhere that it was a little violet in Orion nebula 😀), comparable up to 100x and worse after

From my initial collection of eyepieces and scopes, I kept so far only the 120/600. Rest I have sold and acquire other stuff, because I realized that is not delivering to the expectations, hence no hurry now with 152 or other design- still learning...

Thank you!

On 31/07/2023 at 16:07, The60mmKid said:

@Marian M, I know that you mentioned needing to spend time assessing your options, but I also wanted to throw another idea in for consideration. A 100mm binocular telescope is a brilliant rich-field instrument. With the "binocular summation factor" in mind, the brightness of the views it provides is on par with a ~160mm instrument. If I was after a reasonably portable rich-field instrument for binoviewing, something like that would be my first choice. I'd recommend Teleskop Express due to their outstanding customer service.

@The60mmKid- I already have a Celestron 20x80 binocular, but I am not using it anymore due to the much better optics in the MB2 and APO (even in the 120/600 achro)/ larger flexibility on eyepieces + more convenient view to zenith. Anyway, with the 90 degree binoculars, this is a fair idea and will give some reading on forums how to they compare + mount requirements. Thank you!

@Louis D , @The60mmKid , many many thanks for your patience and advices! Having also an APO close to my 120 achro, I see the difference between the 2 designs and also I acknowledge the mass added for a refractor (both for the device itself, as well as for the corresponding mount) for each single inch added. 

I spend the whole afternoon here browsing from other users experience on 152 achro, as well looking for Newton/ Dobson with binoviewer. The single major drawback of the Newton is the lack of bino-friendliness against the refractor; with some short adapters, the 152 may accommodate binoviewer without GPCs.

As I learn from my own mistakes, better to spend more time with comparing my achro and apo, together with my budies Dobsons and experiment when possible my concern on bino. I become bino addicted after discovering the perfect match of MB2 and Morpheus 17.5, for wide view- only the 100 degree eyepieces will be close as visual experience for me

Will keep you posted once I will decide and share here my experience

Thank you!

Happy to discuss the focusers as well here, I am at the beginning of the Newtons curve learning 😄

Now, the big question- most of the observations I am using either heavy bino (MB + 2 Morpheus) or large eyepieces (APM XWAs) 

Is this suitable for the above Newton, what about the back focus required for Bino. For all my refractors I did changes that all are accommodating the bino without GPCs, for largest FOV possible. Would that work with the newton? Would be a pity to have a design for large FOV which is destroyed by the GPC

Also, being so fast (F/4), I presume the second mirror is large. Would that affect the view through a large 2" 40mm eyepiece like Lacerta/ Paragon (secondary being somehow visible?)

On 25/07/2023 at 15:35, Louis D said:

At low to medium powers on dimmer stars and DSOs, both the 6" achro and 6" fast Newt show similar views.  The Newt doesn't show diffraction spikes on dimmer objects, so that advantage of the refractor is lost.  The unfocused light in the frac is hard to detect, so that advantage of the Newt is lost.

I like having the eyepiece up nice and high on the Newt.  I refuse to extend the legs on my tripod due to the inherent shakiness in so doing, so the refractor's eyepiece ends up a foot or two off the ground which is really uncomfortable.

On DSOs in particular, I see no advantage to the frac over the Newt when you figure in cost, weight, and cool down time (the frac has more glass to cool).

Louis, if I were to give one more chance to the refractor (DSO only), your subjective opinion- which is the aprox magnification where the Newton is becoming crisper than the 152?

Is the 152 yet sharp at 100x? Many thanks again!

On 25/07/2023 at 15:27, Mr Spock said:

Here's my two ready for action. The Dob is next to the shed, and the Tak can go anywhere. Especially useful as my house blocks the East so I can only see there from the top of the garden. The garden runs exactly East to West - North to the right and South to the left 

Wonderful setup, peaceful place, amazing views...

On 25/07/2023 at 15:16, The60mmKid said:

I'd also recommend considering dobs smaller than 300mm if portability/deployability is a concern. A smaller (i.e., 6-10") fast dob can be a wonderful rich-field scope if that's still what we're after. And well collimated, it will also show more detail on planets than a smaller refractor does when conditions allow for it. But then other questions become relevant... thermal acclimation, local seeing conditions, preferences for mount/tracking, etc. If it's still a matter of "x vs. y rich-field scope," then I consider fast dobs quite worthy of consideration... and I'm sort of a refractor guy... or maybe I'm not... maybe I'm confused about my identity... but I digress. All of that aside, if I were to move to a place with dark skies, I'd be itching to get my hands on a fast 10" or 12" dob. One glimpse of the Double Cluster through a 10" f/4 is all it takes...

I love refractors; but reflectors seems winning on the benefits. Here it is my internal debate- one part of the mind is pushing against the rationale towards a bigger, heavier, colorful scope, while the logic part keep pushing back- largest aperture, similar effort to get out. Well, maybe the easiest way is to buy both 

On 25/07/2023 at 14:56, Stu said:

Well it is oft said that the best telescope is the one you are looking through ie the one you use most. If you have easy access to dark skies and can pop a 300mm dob outside easily then it will be a good candidate. If you can lift/ move them easily then a dob can be quicker to setup than lugging mount, refractor and other bits and pieces out. However, if the size/weight/effort makes it less likely to be used then the balance shifts to smaller/light scopes. That’s why my most used scope is a Tak FC100DC on a ScopeTech mount and Gitzo tripod. Easy lift into the garden even for the quickest of sessions.

After the acquisition of the 72 APO, it become my most used scope. 20 minutes today, 15 tomorrow- the time spent in a month is more than a full night of observations once in a month

Later I discovered that 102 APO stays well with a William Optics plate on the video head, hence I presume it will become no 1

Missing one single day and very excited to see so many comments here! 😄

@Stu, yes, your remark is well received- if the sum of Dobson benefits will be larger than the 152’s, I may change my mind. I would like to go more in aperture and checking a lot of boxes at once. Probably the best ever telescope will be the largest one possible, with all time access, in the darkest possible place but in front of my house and the most- belonging to someone else for the rest of headaches. In real life, there is no scope to meet all requirements at once. Many thanks for the simulations you have posted, very often I am doing the same through Stellarium app installed on the laptop, where I can choose the setup and simulate the view. What is missing there, is the visual experience. How far can you push the 152, for DSO only, still having a good view? For 120 ST- I would say max to 60x, for 152 some says even up to 120-150x, which seems a good achievement

@Louis D, I have compared the 120 achro with the 102 FPL53. During the day, as spotting scope, there is no comparison at all. On bright objects, there is a mess of colours in the 120, challenging the focus point, while 102 has a crisp, clear, colour free view. On the other hand, during the night/ DSO only/ low to low-medium power, the difference, for my eyes, is very small and non-disturbing. The 120 is brighter on the same magnification. The question is- you have been so disappointed of 152 for his only role- DSO/ low to medium power? If you can revert with few pictures of the Moon, would be great!

@Mr Spock- very happy with so many choices on scopes and eyepieces. Just to give more headaches while planning which to buy, wondering after purchase why I took this. And the most frustrating- even after all the people here told that you better take a different one. Some of the joy maybe is to buy it and convince yourself that this is not the right choice

Well, to be honest, I suppose is mostly my wife statement 😄😄

I am just closing my eyes, easy come, easy go 😄

Hi friends again, any many thanks for your messages!

Last evening, I had the chance to compare my 102 F7 FPL53 with the same 150 F8 SW ED and with a 300mm Dobson, for 1.5 hours time observation only, all without goto.

The sky was decent, allowing magnification up to 200x-250x, outside the city. Around 21.30, we had all equipment installed and ready to go.

First target was the Moon, with striking details in all 3 instruments. 102 had MB bino with Morpheus 9 and GPC (around 200x), SW 150 ED MB bino with Nikon NAV SW 17.5mm and Barlow (250x) and Omegon Dobson with APM UFF 24. We spent some time on Posidonius crater (hope my memory is good), where Posidonius C (around 3km diameter) was visible in 150 but just maybe/ with peripheral vision in 102, from time to time. Not necessary the best atmosphere to go higher on magnification.

Next targets were Wild Duck, Double cluster, Omega nebula, Ring Nebula, mostly on low power. Just as a personal very subjective opinion, I felt the jump from 102 to 150 was lesser than the jump from 150 to 300, but not that much. Whatever was visible in one instrument, was brighter and richer in the second one. Whatever was barely visible on the first instrument, was clearer in the second one. 102 has enjoyable views by up to 200x, 150 ED and Dobson may go for sure more. The view in the APOs seems sharper vs Dobson. Anyway, much more time is required to compare properly the Apo vs Dobson

I was wondering which one is suiting better my observation style. Last evening, being in hurry, I took only the APO on a video fluid head/ photo tripod, all at once, in one single trip. Setup time- 5 min. If would had the 152 achro, which should be similar on low power/ wide fields with the 150 ED, I should have taken the Skytee at least, more trips from the flat to the car, but quick setup time. With a 300 DOB, probably more trips would have been required but a quick setup time. Storage- the first 2 easy in the furniture, 300 Dobson- a little issue here. Binoviewer (which I enjoy a lot)- easy in the 2 Apos, challenging in Dobson- probably I have to look for the SW version which is collapsible, with the price of some aperture loss.

All these years I have learned that the hurry of acquisition leads to later selling, hence more time spent to study, and experiment is required  

On the short list still there is the 152 Achro but it seems that a Newton/ Dobson has a good chance to win

Hi friends!

It seems that I have developed on obsession over this fast achromat in the past months. I have read probably almost all of the reviews here on SGL and other websites, I know same version is sold under various brands, but not yet clear..

In a nutshell, I have TS 72 FPL53 (ultra GnG), TS 102 FPL53 and SW 120 F5 achro, with video head/ tripod, Skytee and AZEQ6. Most of the times with MB bino and Morpheus, or on cyclop with APM XWAs. Very often quick sessions on the balcon/ city with the 72, once in a month outside the city, with whole arsenal. I had a Mak 127 which I sold after getting the 102 APO, which I found superior on everything. Only visual, I like everything, moon, DSOs and planets, every single observation is giving me that smile and happiness as probably to most of you

Last evening I had the chance to compare pretty well on a variety of DSOs my 102 APO, with my friends SW 150/ 1200 ED and C8. My personal and very objective opinion is that most of the things which I see in 150 are visible in 102 as well, but better and brighter, is not necessary a fundamental difference. C8 sometimes shows more that 150ED but I like the APO view more than the C8- wider views and crisper images. Once again, just my personal impression, others could be different. So don't shoot me.

The 120 ST was not here to compare but in a previous session I did an 102 APO vs 120- on up to 50-60x magnification, not a huge difference. Stars maybe crisper, cleaner image in APO but DSO brighter in 120. Above that magnification, the APO is gorgeous, the SW 120 fail

Setting up the context, my question to you is where would be 152 F5.9 between the 120 ST and the 150 SW ED, only for DSO and up to 100x magnification? Would be better than 120 F5, would be similar to SW 150ED for wide low/ medium power? Is a big difference between 120 F5 achro and 152? from my preliminary computations, the 152 can accommodate bino without GCP easily, with some adapters change. TS give clear data on backfocus, which I found true for the 72 and 102.

There are also some observations planned when a friend will come with a 300 Dobson, maybe that will be a gamer change. In between, if I will sell the 120, the difference to 152 F5.9 will be manageable as cost, but does it worth?

PS the 120 F5 is changed completely on focuser part, now works at full aperture and can accommodate bino without GCP