Lunt LS80 - Binoviewer Eyepiece Shootout TV Pan 19 vs TV Delite 15 vs Lunt 21-7.2 Zoom
Posted: Fri Jun 11, 2021 9:45 pm
Lunt LS80 – Binoviewer eyepiece shootout TV Pan19 vs TV Delite15 vs Lunt 21-7.2 Zoom[/i]
I have recently been using my Lunt LS80 THa single stack with a Baader Giant Mk V binoviewer fitted with a 1.75x GPC.
In order to get focus with the bino, I had to remove the spacer between the etalon and the focuser unit. The focuser is then attached to the etalon using the same three grub screws. Using the 1.75 GPC, focus is around halfway along the crayford focuser without pulling the Blocking filter out at all. Its almost as if Lunt designed the scope around the MK V because its so perfect.
I use the 1800 blocking filter. There is no vignetting and the disc is beautifully and evenly lit across the whole diameter. There is no ‘sweet spot’ and it’s a joy to observe using the binos which give that natural 3D view. In addition, binos provide more contrast (must be sometime to do with using both eyes together) and I find I can observe for longer because the eyes do not get so tired.
Ok so on to the shootout. Its between the Televue Panoptic 19mm (Mag 52x) vs Televue Delite 15mm (Mag 65x) vs Lunt 21-7.2mm Zoom (Mag upto 136X). I have selected these Eps because I already successfully use the 19 & 15mm with my nighttime scopes. The Lunt Zoom because they offer increased magnification and flexibility as zooms. I was also interested to see if the Lunt coatings would increase contrast for a given similar magnification compared to a night time EP.
I have decided to rate them by Comfort, viewing Proms and viewing Surface Detail. 19mm Panoptic
Comfort - The most comfortable EP of the 3 to use. Its small and light and tapers away from the eyecup. A perfect shape for binos and to be able to get your nose between the Eps. The Pans are also very forgiving about eye placement without kidney beaning. Score 3 points
Viewing Proms – The Pans give a fantastically bright view. The proms really are very bright and almost have their own fire. Faint proms are easy to see. BUT the pans are only x52 mag, which means that the image does not fill the whole view and there is quite a big gap of blackness from the edge of the sun to the edge of the EP. The image is too small for my tastes. Score 3 points
Viewing Surface Detail – The Pans are again very sharp but they are also very bright and do not offer a decent amount of contrast, probably because the image is too small. Don’t get me wrong, it’s a wonderfully sharp view, just when they are up against the others in this shoot out, they don’t quite cut the mustard. Score 1 point.
15mm Delite
Comfort – These are big EPs for a binoviewer. The eyecup does not taper at all and the diameter is quite large. This is then compounded if the rubber eyecups are raised. That said, I have now found the best compromise. I set the eye relief at its lowest setting and roll up the rubber eyecups. The position is no where near as comfortable as the Pans, but usable. Score 1 point.
Viewing Proms – The reason for compromising with the comfort is the view of the Proms. The sharpness and level of detail that can be seen with the Delites is jaw dropping. A ‘normal’ prom is transformed into a complicated beautiful object in its own right. Individual blobs of plasma can easily be seen along with the complex structure.
Faint proms seem to have their own internal illumination and detail can be seen easily. With reasonable seeing, the spicules at the edge of the sun can easily be seen in lovely detail. I use these to gauge the seeing. The best EP here for viewing proms. Score 5 points
Viewing Surface Detail – The Delites are wonderfully sharp so it is very easy to see sunspots, plage filaments and the lines of magnetic flux around the sunspots and filaments. The contrast is very good and the ‘orange peel’ is easy to see. Solar flares stand out as bright lights against the contrasty background. I thought the surface detail could not be beaten, but read on. Score 4 points.
Lunt 21-7.2 Zoom
Comfort – The Lunt is neither as comfortable as the Pans or as uncomfortable as the Delites. Its in the middle of the two. There are no roll up eyecups. Instead you get a hard rubber adjustable cup that you can adjust the eye relief by twisting up and down. I fine the best position is the lowest setting. Comfort is Ok, score 2 points
Viewing Proms – Because the lunt is a zoom, I was able to set its magnification to be the same as both the Pans (19mm) and Delites (15mm) to do a direct comparison of lens quality and sharpness. It will come as no surprise that the Lunt was not as sharp as either the Pans or the Dels. It was not far behind either of them, but if you are looking for absolute sharpness then fixed length EPs are always going to win out. The Lunt, however, can play its trump card by increasing magnification. I found that between 13.5-10mm was the best compromise between mag and resolution on the proms, but I preferred the Delites at 15mm. Proms were very good, score 3 points
Viewing surface Detail – This is where the Lunt really came into its own. Again I did the direct mag comparison with the other two shooters. The Lunt consistently showed more contrast and it was easier to see more detail. The real joy of this EP was when I cranked up the mag to 10mm (98x) or with good seeing, 7.2mm (136x). The contrast increasing dramatically and a sunspot or filament becomes a object of beauty with lovely detail. I think Lunt must put a coating on their eyepiece to enhance the solar view. I am asking myself the question of whether I need a double stack because the Binos coupled with the high mag zoom give a really constrasty view without the hassle of setting the PT on the second stack and the red glow associated with the internal DS. Surface detail is awesome, score 5
Conclusion
There is no such thing as the perfect eyepiece. I use the 15mm Delites for the Proms and the Lunt Zoom for the Surface because of the contrast at high mags. If I had to choose just one pair? That’s a really difficult question to answer. I think it would be the Lunt Zoom because its so versatile and the high mag surface views are intoxicating, but the sharpness of the Delites is awesome.
Clear skies to you all.
I have recently been using my Lunt LS80 THa single stack with a Baader Giant Mk V binoviewer fitted with a 1.75x GPC.
In order to get focus with the bino, I had to remove the spacer between the etalon and the focuser unit. The focuser is then attached to the etalon using the same three grub screws. Using the 1.75 GPC, focus is around halfway along the crayford focuser without pulling the Blocking filter out at all. Its almost as if Lunt designed the scope around the MK V because its so perfect.
I use the 1800 blocking filter. There is no vignetting and the disc is beautifully and evenly lit across the whole diameter. There is no ‘sweet spot’ and it’s a joy to observe using the binos which give that natural 3D view. In addition, binos provide more contrast (must be sometime to do with using both eyes together) and I find I can observe for longer because the eyes do not get so tired.
Ok so on to the shootout. Its between the Televue Panoptic 19mm (Mag 52x) vs Televue Delite 15mm (Mag 65x) vs Lunt 21-7.2mm Zoom (Mag upto 136X). I have selected these Eps because I already successfully use the 19 & 15mm with my nighttime scopes. The Lunt Zoom because they offer increased magnification and flexibility as zooms. I was also interested to see if the Lunt coatings would increase contrast for a given similar magnification compared to a night time EP.
I have decided to rate them by Comfort, viewing Proms and viewing Surface Detail. 19mm Panoptic
Comfort - The most comfortable EP of the 3 to use. Its small and light and tapers away from the eyecup. A perfect shape for binos and to be able to get your nose between the Eps. The Pans are also very forgiving about eye placement without kidney beaning. Score 3 points
Viewing Proms – The Pans give a fantastically bright view. The proms really are very bright and almost have their own fire. Faint proms are easy to see. BUT the pans are only x52 mag, which means that the image does not fill the whole view and there is quite a big gap of blackness from the edge of the sun to the edge of the EP. The image is too small for my tastes. Score 3 points
Viewing Surface Detail – The Pans are again very sharp but they are also very bright and do not offer a decent amount of contrast, probably because the image is too small. Don’t get me wrong, it’s a wonderfully sharp view, just when they are up against the others in this shoot out, they don’t quite cut the mustard. Score 1 point.
15mm Delite
Comfort – These are big EPs for a binoviewer. The eyecup does not taper at all and the diameter is quite large. This is then compounded if the rubber eyecups are raised. That said, I have now found the best compromise. I set the eye relief at its lowest setting and roll up the rubber eyecups. The position is no where near as comfortable as the Pans, but usable. Score 1 point.
Viewing Proms – The reason for compromising with the comfort is the view of the Proms. The sharpness and level of detail that can be seen with the Delites is jaw dropping. A ‘normal’ prom is transformed into a complicated beautiful object in its own right. Individual blobs of plasma can easily be seen along with the complex structure.
Faint proms seem to have their own internal illumination and detail can be seen easily. With reasonable seeing, the spicules at the edge of the sun can easily be seen in lovely detail. I use these to gauge the seeing. The best EP here for viewing proms. Score 5 points
Viewing Surface Detail – The Delites are wonderfully sharp so it is very easy to see sunspots, plage filaments and the lines of magnetic flux around the sunspots and filaments. The contrast is very good and the ‘orange peel’ is easy to see. Solar flares stand out as bright lights against the contrasty background. I thought the surface detail could not be beaten, but read on. Score 4 points.
Lunt 21-7.2 Zoom
Comfort – The Lunt is neither as comfortable as the Pans or as uncomfortable as the Delites. Its in the middle of the two. There are no roll up eyecups. Instead you get a hard rubber adjustable cup that you can adjust the eye relief by twisting up and down. I fine the best position is the lowest setting. Comfort is Ok, score 2 points
Viewing Proms – Because the lunt is a zoom, I was able to set its magnification to be the same as both the Pans (19mm) and Delites (15mm) to do a direct comparison of lens quality and sharpness. It will come as no surprise that the Lunt was not as sharp as either the Pans or the Dels. It was not far behind either of them, but if you are looking for absolute sharpness then fixed length EPs are always going to win out. The Lunt, however, can play its trump card by increasing magnification. I found that between 13.5-10mm was the best compromise between mag and resolution on the proms, but I preferred the Delites at 15mm. Proms were very good, score 3 points
Viewing surface Detail – This is where the Lunt really came into its own. Again I did the direct mag comparison with the other two shooters. The Lunt consistently showed more contrast and it was easier to see more detail. The real joy of this EP was when I cranked up the mag to 10mm (98x) or with good seeing, 7.2mm (136x). The contrast increasing dramatically and a sunspot or filament becomes a object of beauty with lovely detail. I think Lunt must put a coating on their eyepiece to enhance the solar view. I am asking myself the question of whether I need a double stack because the Binos coupled with the high mag zoom give a really constrasty view without the hassle of setting the PT on the second stack and the red glow associated with the internal DS. Surface detail is awesome, score 5
Conclusion
There is no such thing as the perfect eyepiece. I use the 15mm Delites for the Proms and the Lunt Zoom for the Surface because of the contrast at high mags. If I had to choose just one pair? That’s a really difficult question to answer. I think it would be the Lunt Zoom because its so versatile and the high mag surface views are intoxicating, but the sharpness of the Delites is awesome.
Clear skies to you all.