Binoviewer conundrum

[Stu]

I recently posted up that I had finally got the hang of binoviewers after having bought a pair of Baader Zeiss Mark IV's. I have a pair of Zeiss 25mm Orthos, plus Denk D14's and various barlows to use and with the Herschel Wedge I definitely got an improvement in contrast and perceived depth to the image, plus the more relaxed nature of observing with both eyes. The detail seen at times of good seeing was quite amazing.

All good then you say?

Well.... Not quite, is the answer.

On the night of the 4th, I was observing Jupiter with the Tak and decided to try the binoviewers out again. I tried multiple different configurations of Barlow and eyepiece, varying the magnification but at no point was I able to get the same level of detail that I achieved with the Leica Zoom and Barlow. It was very strange, the image had more depth and colour to it in the binoviewers, it looked much richer if you like, but the fine detail just wasn't there to the same degree. It just doesn't make sense to me.

I will try them out on the moon as I suspect they will be excellent there, plus on some deep sky objects too. They are worth keeping for the solar views alone but it would be nice to understand the planetary problem. I'm guessing it is just 'my eyes!'

One comfort; at least I don't have a problem with in focus on the Tak. The opposite problem in fact!! ?? I can easily reach focus with no Barlow for low power work.

[DRT]

Interesting review, Stu.

As you know I recently acquired a binoviewer for solar and have had the same "WOW!" experience as you. I have not yet tried them on planetary or deep sky but will do so as soon as the sky allows and report back here

 

[jetstream]

Hi Stu, one thing I noticed in my brief bino experience is that using the diopter adjustment to equalize the EP focus really sharpens the view. Before I bought the 2nd 25mm TV plossl I checked to see how high this EP could barlow and if it even liked the barlow- and it really did. The Denk 14 is supposed to be very sharp, but have you tried it cyclops barlowed and compared it to the LZ? or the 25mm Zeiss?

Plus the LZ is just plain old good, really good.....

[dweller25]

Stu - I have also noticed that going from Baader/Zeiss prism plus Leica ASPH zoom gives a sharper view than the Baader/Zeiss prism plus Baader MK V's and TV Plossls.

I think it's because the Baader MK V's take a long time to cool down as I have some really sharp results from the Binoview combo when given time to cool.

[Stu]

1 hour ago, jetstream said:

Hi Stu, one thing I noticed in my brief bino experience is that using the diopter adjustment to equalize the EP focus really sharpens the view. Before I bought the 2nd 25mm TV plossl I checked to see how high this EP could barlow and if it even liked the barlow- and it really did. The Denk 14 is supposed to be very sharp, but have you tried it cyclops barlowed and compared it to the LZ? or the 25mm Zeiss?

Plus the LZ is just plain old good, really good.....

Thanks Gerry. I did wonder this, and experimented a little with it. The Mark IVs don't have individual focusing, but the Zeiss Orthos do have diopter adjustment so I was able to make sure both channels focused correctly. With the Denks I just slightly adjusted the position in the eyepiece holder and that got pretty close I think.

Looking through one channel at a time still showed the less detailed image. I'll try testing the D14 vs the Lieca to see how they compare. I was impressed with them on the sun....

39 minutes ago, dweller25 said:

Stu - I have also noticed that going from Baader/Zeiss prism plus Leica ASPH zoom gives a sharper view than the Baader/Zeiss prism plus Baader MK V's and TV Plossls.

I think it's because the Baader MK V's take a long time to cool down as I have some really sharp results from the Binoview combo when given time to cool.

That's interesting........ I hadn't even thought about cooling. I know the Zeiss prism takes a while to cool, unlike mirror diagonals, so it makes sense that the Binoviewer would too. I'll give that a go next time out.

Thanks both

[YKSE]

The biggest advantages with binoviewers are relaxed two eyes, in addition to summation effect, from my limited experience, relaxed eyes have two more noticeable effects on me:

1. Very few floater even with exit pupil as small as 0.7-0.8mm.

2. very much less scatters from my own eyes. Viewing on Jupiter in cyclops, I see quite a lot scatters from my eye(rotating my head, the scatter pattern rotates too; and the pattern doesn't change if rotating the eyepiece). these scatters are not perceiveable when binoviewing.

I always check the diopter setting, cover the EP in diopter side first, focus. then change cover, addust the diopter. My none-dominant eye is not as good, but it does help quite noticeablly when both eyes are in focus.

The not-proper-cooled binoviewer prism should have negative impact, especially that Mark IV had bigger prism than other cheaper binoviewers.

[YKSE]

There's one more thing. It happens to me from time to time, that I only look with the dominant eye, when Jupiter has drifted a bit off-center, despite that I use tracking mount albeit only quick-aligned. The dimming didn't feel like very noticeable. Nowadays, I do the close-one-eye test from time to time during binoviewing, just to ensure that both eyes are in action.

[Stu]

On 6 April 2016 at 23:51, YKSE said:

The biggest advantages with binoviewers are relaxed two eyes, in addition to summation effect, from my limited experience, relaxed eyes have two more noticeable effects on me:

1. Very few floater even with exit pupil as small as 0.7-0.8mm.

2. very much less scatters from my own eyes. Viewing on Jupiter in cyclops, I see quite a lot scatters from my eye(rotating my head, the scatter pattern rotates too; and the pattern doesn't change if rotating the eyepiece). these scatters are not perceiveable when binoviewing.

I always check the diopter setting, cover the EP in diopter side first, focus. then change cover, addust the diopter. My none-dominant eye is not as good, but it does help quite noticeablly when both eyes are in focus.

The not-proper-cooled binoviewer prism should have negative impact, especially that Mark IV had bigger prism than other cheaper binoviewers.

Interesting points Yong. I do still notice floaters at high power but they seem much less intrusive than with cyclops viewing.

My non dominant eye is also significantly worse for Astro viewing than my dominant one. It is perhaps why I have not got on with binoviewers in the past. With the Baaders though the images merge very well, and the detail is definitely there in solar viewing. The prisms are big - 28mm if I remember correctly, so they will take longer to cool. I guess that could explain why solar is good and planetary less so?

14 hours ago, YKSE said:

There's one more thing. It happens to me from time to time, that I only look with the dominant eye, when Jupiter has drifted a bit off-center, despite that I use tracking mount albeit only quick-aligned. The dimming didn't feel like very noticeable. Nowadays, I do the close-one-eye test from time to time during binoviewing, just to ensure that both eyes are in action.

I too check this with the blink test. It's very reassuring to see both channels aligned when you do this too!