Ed Ting on eyepieces

[Elp]

My personal opinion on the video, "there's lots of other capable eyepieces, and there's Televue". His videos are an enjoyable watch.

Edited May 10, 2023 by Elp

[doublevodka]

Really like Ed's videos and as usual a balanced view although he should definitely be on TeleVue's payroll 😂

While I don't have anything green and black in my collection, 2 eyepieces and a Barlow are what work for me for a general observing session so there's a lot of sense to what he's saying. Using anything more just ends up frustrating, and more to pack away afterwards 😂

[Don Pensack]

When I owned one of those 127 Maks, I, too, used about 2 eyepieces.  That was because a 32mm and 24mm yielded the same true field, so why not use a 24mm and get a darker background sky?

And because a 13mm yielded a 1mm exit pupil, which was high power in that scope.  24mm and 13mm would do fine for most observing.

In my dob, however, I can get much larger exit pupils for low power and a 1mm exit pupil is a high power (320x).

So I have 10 eyepieces in that range and use at least 8 of them on any random night.

It could be fewer if I used a Barlow.

[Louis D]

2 hours ago, Don Pensack said:

And because a 13mm yielded a 1mm exit pupil, which was high power in that scope.  24mm and 13mm would do fine for most observing.

Sounds like a 13mm Ethos might be the only eyepiece you'd need in a 127 Mak most nights if you could deal with the eye relief.  It would almost combine the 24mm and 13mm eyepiece functions into one.

[Don Pensack]

9 hours ago, Louis D said:

Sounds like a 13mm Ethos might be the only eyepiece you'd need in a 127 Mak most nights if you could deal with the eye relief.  It would almost combine the 24mm and 13mm eyepiece functions into one.

The 24 was wider in true field, and brighter.

[Louis D]

7 hours ago, Don Pensack said:

The 24 was wider in true field, and brighter.

Of course, but what about the increased contrast due to the darker sky background?  That, and Uncle Al's whole "Majesty Factor". 😏

[Don Pensack]

1 hour ago, Louis D said:

Of course, but what about the increased contrast due to the darker sky background?  That, and Uncle Al's whole "Majesty Factor". 😏

No question the 13mm was engaging.  I used eyepieces all the way to 4.7mm in that scope.

But I started out with a 32mm Plössl to get as wide a true field as possible in the scope with 1.25" eyepieces.

 

In my light-polluted environment, though, the 24mm yielded the same true field with a darker background.

A 13mm (at the time it was a 13mm T6 Nagler) was excellent, and used a lot, but it had an appreciably smaller true field.

The 13mm Ethos hadn't come out back then.

 

I used the 24mm and 13mm a lot with the Mak.  Field stops of 27mm and 16.7mm respectively.  The 13mm Ethos would be in between.

It would still suffer from a small exit pupil, though.  Even a 24mm had an exit pupil smaller than 2mm.

The 127 Mak cries out for a low power eyepiece of 40mm, but in a 1.25", that would be a very narrow apparent field.

What the scope lacked was large exit pupils and wide fields.  I would have been happier with a short focal length refractor.

 

Not long after, that is exactly what it was replaced with--a TeleVue NP101, which had a focal length close to 1/3 that of the Mak.

The same eyepieces worked great, and by then I had a 13mm Ethos that got a lot of use--MORE than the 24mm.

In that short scope, though, an 8mm eyepiece gave the same magnification as the 24mm in the Mak, and I used eyepieces down to 3mm with it.

 

 

[John]

20 hours ago, Louis D said:

Sounds like a 13mm Ethos might be the only eyepiece you'd need in a 127 Mak most nights if you could deal with the eye relief.  It would almost combine the 24mm and 13mm eyepiece functions into one.

I used my 13mm Ethos with my 100mm F/9 refractor last night and the views were superb 😁

Plus the true field was large enough to allow both Messier 13 and the nearby galaxy NGC 6207 to appear in the same view at 69x. Spotting a 12th magnitude galaxy in my skies with a 100mm aperture scope can be tricky and the additional magnification really helps tease such targets out.

Edited May 11, 2023 by John

[JeremyS]

25 minutes ago, John said:

I used my 13mm Ethos with my 100mm F/9 refractor last night and the views were superb 😁

Plus the true field was large enough to allow both Messier 13 and the nearby galaxy NGC 6207 to appear in the same view at 69x. Spotting a 12th magnitude galaxy in my skies with a 100mm aperture scope can be tricky and the additional magnification really helps tease such targets out.

That’s an impressive result John - and a great combo of two DSOs 👍🏻

[John]

2 minutes ago, JeremyS said:

That’s an impressive result John - and a great combo of two DSOs 👍🏻

Thanks Jeremy. My next intended target with the 100mm last night was going to be the quasar in Virgo 3C 273 which is mag 12.9 but the clouds spoiled the fun. 

[bomberbaz]

1 hour ago, John said:

Thanks Jeremy. My next intended target with the 100mm last night was going to be the quasar in Virgo 3C 273 which is mag 12.9 but the clouds spoiled the fun. 

Be interested how you get on with that John. I would also be interested in hearing your finding process for it.

I have had it once using the dob, but that has DSC so that's relatively easy in comparison.

[John]

34 minutes ago, bomberbaz said:

Be interested how you get on with that John. I would also be interested in hearing your finding process for it.

I have had it once using the dob, but that has DSC so that's relatively easy in comparison.

I have done it before with the 100mm. Star hopping from 6x30 RACI then to a low power eyepiece and finally more power to tease the faint point source out.

Stellarium shows it if you load the quasars catalogue. This article is quite useful as well:

Cosmic Challenge: Quasar 3C 273 - Phil Harrington's Cosmic Challenge - Articles - Articles - Cloudy Nights

It can vary in brightness however so if it is experiencing a "dim" phase then 100m will stuggle I think.

 

[Mr Spock]

I have some charts for 3C 273 - 20°, 5° and 1°. The 1° goes down to mag 16

[The Lapwing]

I like Ed Ting and his video reviews.

I hope he has a thick skin, not nice to get savaged on line in front of your peers. I see the thread in question has been locked.

[John]

38 minutes ago, The Lapwing said:

I like Ed Ting and his video reviews.

I hope he has a thick skin, not nice to get savaged on line in front of your peers. I see the thread in question has been locked.

A few years ago Ed made some comments on the performance of an optical item which were based on his mis-understanding of the method of use. He admitted this when challenged and then withdrew from reviewing for some time.

Personally I'm pleased that he started doing them again 🙂

[garryblueboy]

I also like Ed’s reviews they are as he states just his opinion Televue are like Takahashi scopes there is more quality Controll in there equipment but doesn’t mean there the best like Takahashi I’ve owned quite a few Tak scopes all were great but I’ve also owned others and do now which are above them in quality and performance and some well below half the cost with 95% of the performance . I use some very nice APM flat field eyepieces for my binoculars as well as Tele Vue  Panoptics with comparable results .

[AstralFields]

I wouldn't have agreed with him half a year ago but as I continue going through the Messier catalog of objects I do find myself using two eyepieces the most (if I don't count the 2" 40mm for finding stuff)

26mm 2" 70 for an initial view of the object

15mm 1.25" 68 for a comfortable close-up.

I am not much of a planets guy (like 5-10 minutes per observing night). In that case the 6-9mm works fine. The 9mm just feels like too much for DSOs.

So basically I permanently attach a small 2" to 1.25" circle adapter to the 15mm and swap between the 40,26 and 15 for most of the night in the 2" focuser.

For very dim galaxies I do like to use a zoom eyepiece to tease out the optimum magnification.

Based on Telescope magnification (telescope-optics.net) , one can already see 90% of the details that can be seen with only 10-15x magnification per inch of aperture. Strangely, even though I liked high power in the beginning, I rarely find myself bothering to go over 100x on my 8" DOB.