TTT296 Telescope Eyepieces Pt 2

[@gregorythomas333]

This is very useful...I am getting interested in astronomy...so this information is invaluable to me. Thank you Tom :)

[@stevemyers7698]

I just watched your video, I just bought a set of SVBony eye pieces. The difference between them and the ones I got with my 8”dob, are night and day. I think I will try a set of 2”. Thank you.

[@ironclad29]

This helped me so much with eyepieces thank you

[@ALSutton]

Good video mate. I'd love to see you show your setup outside.;-)

[@premanand7803]

Hi hope you are safe sir, Yours videos are very useful and gained me some knowledge on eyepieces I always wonder looking at eyepiece (virtually) that How do you determine the focal length of eyepiece like 8mm or 16mm or so How do the lens in eyepiece are placed in order to get the required focal length Can we make one I am really interested in making one & Can you tell about working principle of an eyepiece you had of 8mm-24mm It's really very interesting

[@lornaz1975]

Do you observe with your telescope from your living room through those windows?

[@A0111.]

SvBony aspheric set isn't the best choice, as top plastic lenses can be easily scratched by even a gentle cleaning, and 4mm simply isn't sharp (it is actually Barlowed 8mm eyepiece). I like their more expensive gold or red series, though they have other imperfections (beaning)

[@resiggy13]

Hi. So for us complete neophytes maybe you could take a few minutes and describe how the various focal length lenses differ. I really don't understand how what you see will be different when looking through the 4 mm focal length lens vs the 23 mm focal length lens. I'm sure it has to do with the magnification factor but which will make things appear larger and which will make things appear smaller. Thanks.

[@tomtektest8042]

Good suggestion. I will bring forward a video I planned to make near the end of the Astronomy/Telescopes series and try to finish it today or tomorrow. In the meantime I suggest you got to the Orion Telescopes page on KZbin and watch two videos, the first on Choosing a Beginner Telescope and the second on Choosing Eyepieces. I may have the titles a little off but I am sure you will find them easily - in the meantime I will get started on the video I mentioned. It is easy to forget things you learned years ago and now take for granted and your suggestions prompted me to realize that this kind of information might be better earlier, rather than later in the series. Thanks again for the suggestion.

[@resiggy13]

@@tomtektest8042 Thanks for the referral to the 2 Orion videos. I've watched both (And many more) and found them to be excellent. I can't wait to see your take on the topic. Thanks for making and posting this information!

[@tomtektest8042]

I'm glad they helped. I also think the Orion videos are excellent. I am planning to release a video later today or tomorrow that fills in some areas for beginners that may not be in the Orion videos. Hope you enjoy it.

[@k.h.1587]

While i like some of the components in that 2" kit, I dont think it is a good value. The only filter that you need is the moon filter, and the diagonal is not dielectric, just a standard aluminum. The eyepieces are only 3 element modified wide angle kellners. Meade also sells the exact same kit now. They are all made by GSO. Buying a dielectric diagonal and a better 40mm like a 38mm Q70 or william optics 40mm swan was a better way to go. The SvBONY eyepieces use glass lenses, only the aspheric series has a single plastic lens, the rest are glass. Others watching this should know that the 2" kit is trash in fast scopes, and even the Q70 type eyepieces are not sharp to the edge in fast scopes. That is where the meade ultrawide, and other nagler clones like the ES82 and panoptic and panoptic clones ljke the es68, are needed for sharp to the edge performance. Other "internally barlowed" designs can also be sharp to the edge, such as pentax xw, vixen LVW, hyperion, and many of the planetary long eye relief designs. But wide field kellner konig and erfle variants are only good in slow scopes, f7/f8 and slower. For even slower.scopes like SCT, these eyepieces perform reasonably well. Note that the 26mm in the kit is only 56deg and could have fit in a 1.25" housing. But even though the 32 and 40mm are advertised to also be 56 degrees, they are actually wider at about 65degrees. In fact, the 40mm has a wider true and apparent field than the 42mm GSO superview, which is advertised at 65deg but is actually more like 60-62 in the 42mm and around 52-55deg in the 50mm. The 3 element kit eyepieces actually do have good contrast and light throughput due to having less glass, which is helpful for faint DSOs. I used the 40mm e-lux (kit ep that I got used by itself) often as an outreach eyepiece that lived in my 8" meade lx200R ota case. I now have an older astrola branded version of the same eyepiece, that is filling the hole in my set, where a nicer japanese made 40mm superwide that uses the maximum 2" field or very close to it, like a UO MK70, TV widefield, or meade 4000swa, the one I used to own, would be. I had all my equipment stolen from storage in 2018, and replaced some of it with less expensive vintage stuff, like a powerstar C8, and a 10" meade LX premiere (f10 version of LX6) to replace my c11/g11 setup. That 26mm 5 element smoothside meade super plossl is indeed excellent and I was lucky to get it (and a few others) with the used 10", and the 26mm celstron/vixen silvertop plossl with the c8. But I generally prefer my 65deg LVWs, 82-84 deg meade UWAs and lone nagler (I had more in my pre storage theft days), and my 28mm megaview (82deg UWAN/PWA type) and 20mm WO XWA 100deg. I also have a 24mm ES68 that I mainly got for my 1.25 limited xt6 dob, orion ST80, and meade 114 lightbridge (which got lent/lost, refusal to return), as well as my etx90 ota. But I can also use it in my bigger scopes as I have a hole between my 28mm and 20/22mm eyepieces. Sometimes exit pupil size is more important than true field of view, and even though the 24mm es68 is much narrower field than 20mm XWA, sometimes you need a little more brightness. One of my regrets in my previous pre 2018 incarnation was selling my 23mm axiom lx (same as 24mm UWA/es82 so really it was 24mm) because it had the same true field as my 20mm ES100 (I especially miss my 14mm ES100, but the 20xwa is significantly better than the 20mm es100, and the 28mm megaview is close enough to the 31 nagler for me to be very happy, other than the 3mm focal length difference and wider true field of the 31)

[@vijay6543211]

Dear sir. I want you to send your excellent pics to me. 👍.

[@oz6123]

Don't need to be an Eyepiece snob that buys only TV Naglers ES 100 degs ones. Save your money. I'm for SVBONY.