After a few decades with a 160mm hyperbolic f/3.3 corrected Newtonian being my primary scope, supplemented by a 100mm Cat, I ventured into refractors after a long, unintended delay in 2018. Because I had a strong affinity to my flat field Newtonian astrograph for visual, I wanted to confirm to myself that fast flat field quads would similarly be the best route for refractors for me. So the first refractor I bought was a Stellarvue f/6, 80/480 LOMO. I knew a quality triplet would be razor sharp, but my intent was to put a Takahashi FSQ-85ED flat field quad astrograph up against it, and choose a winner. I ended up adding a TSFlat2 flattener to the LOMO, and then soon acquired an FSQ-85ED for the smackdown. Plus an f/7.5 80/600 LOMO to boot.
There is no useful criticism of a LOMO triplet. I have two of them, and both look essentially perfect to me, with scintillating, high-contrast, ice-cold views. There is also no useful criticism of the Takahashi 85mm quad astrograph. It has similarly high-definition views, but it substitutes more color nuance and organic subtlety for the ultra-etched white-on-black definition of the LOMOs. They are "the same but different." Variations on a theme.
Then I wanted to find out what differences between easy and compact, fast 80mm scopes and 100mm+ counterparts would materialize. I established the value of the FSQ quad at 85mm, so I stepped up to the 106mm FSQ-106 EDX. When seeing is exceptional, the 106 reveals discernibly more detail in any target it's pointed at. It's not a revelatory difference, but it's noticeable. When seeing is poor, the 80-85mm alternatives are more useful. Now, you can accomplish this with an aperture mask, but all I can say is, it's not the same as stepping down to a dedicated smaller, high-definition optic. The 106 is more revealing of small details than the ~80s, but it is also bulkier, heavier and a bit less spontaneous.
I then went smaller because both seeing at times, and more perfect optics in the form of Takahashi FOA-60Q and FS-60Q, fulfilled their theoretical promise for outperforming intrinsic expectations from their aperture, and proving incisive under specific conditions while also serving spontaneous interests.
Now, almost two years later, I could sell my two 80mm LOMOs. I use them least among my refractors, which isn't the same as saying I appreciate them less than I did at the outset. Maybe I will sell them to help pay for the TeleVue NV compound apparatus. Or maybe not. I am not financially required to give them up and they present a slightly different aesthetic than the nuanced, less binary quads. Is keeping them necessary? No. Is it interesting? Yes. The outcome is uncertain. I can only say that I will keep my two FSQs and they will not leave for keeping the LOMO triplets.
The subtlety of differences between various similar-size & similar-execution refractors is greater than between similar size-and execution reflectors. The aesthetic differences are beyond the objective diameter differences, and the hardware itself is unusually engaging in a tactile sense. You really have the sense that all the light is going through glass, rather than bouncing off of it. Is there a truly objective reason to keep both a compact 80mm refractor and a manageable 100+ mm refractor? No; or at least that's debatable. Refractors in general give me better views of high-magnification objects than my f/3.3 reflector but is there any real difference in the pleasure of using all of them? No. But depending what I am looking to see, and the sky conditions overhead, sometimes my 60mm f/15 is the right tool, and sometimes my 80mm f7.5, and sometimes my 106mm f/5, and sometimes my 85mm f/5.3. And sometimes my 160mm f/3.3. And sometimes my 60mm f/10. I bought the 80mm LOMOs as a triplet reference to test whether my preference for astrographs would persist in refractors. It did. But the LOMO triplets are convincing and interesting so for experiential reasons I have so far kept them. The 60mm Takahashi quads are again their own thing entirely -- a chance to see virtual perfection without unobtainium prices. Where does a RedCat 51 v2 Petzval fit? Stunning wide-field, flat-field views from a scope small and light enough to take anywhere, no matter what your limitations.
This is how people end up with multiple refractors.
Edited by 213Cobra, 29 November 2019 - 02:59 AM.