Another eyepiece enquiry, Revelation!

[bomberbaz]

http://stargazerslounge.com/topic/208123-omegon-super-plossl-eyepiece/

I did make an enquiry about the Omegon eyepiece and all thanks to John for replying. I do agree with the eye relief being very tight so I delved and found this as a potential alternative.

http://www.harrisontelescopes.co.uk/acatalog/Revelation_4.0mm_Plossl_Eyepiece_1.25__.html

Not as fancy looking as the Omegon (I do like the aesthetics) but over twice as much eye relief so possibly an easier view. Anybody got any views or reports on the Revelation ep's?

TIA Steve

[AstroTux]

I bought one of these quite some time ago for use in my AstroMaster 130, but have to say that I just don't get on with it. Personally I find the eye relief quite short and it can be a bit of a pain to use. Since getting the 5mm BST StarGuider for my 250px, the Revelation EPs don't get a look in . Much better eye relief and visual quality all round IMHO.

just my twopence worth, but hope it helps,

Alan

[John]

I think the Revelation plossls are made by GSO so thats a good thing as GSO plossls are pretty good. The eye relief issue remains as the vendor honestly points out in the text although I have to say that he blows it in the specs where the 6mm eye relief can't be correct - as far as I know the very nature of the plossl design means that ER is around 80% of the focal length at best. 

[bomberbaz]

Cheers fella. I think i agree with you john in that looking at all other plossls from other manufacturers that the rev's 6mm seemed rather speculative. The 2.3mm quoted by the Omegon being more realistic. A pity that BST and Celestron Xcels dont come at 4mm. So really need to look at other options if more ER is required, more pondering but cheers.

When your looking at a 100/F4 mirror the extra mm makes a hell of a difference!!!!!!!!!!!!

[Reeny]

They are slightly cheaper here http://www.telescopehouse.com/acatalog/Online_Catalogue_Revelation_Eyepieces_34.html

I have the 9mm and 12mm which I use Barlowed on the 8-inch

Also used with a 1.5x screw on magnifier on the 3-inch.

They work great on the 3-inch at 52 degrees.

And they work well on the dob (12mm barlowed for Jupiter = 220x)

Good enough for planetary work.

But not wide enough for the moon after using a 68 or 82-degree eyepiece.

Great eyepieces.

But as reported above - the 6mm / 4mm versions might be dodgy for eye relief.

If you don't wear glasses, you might get the 9mm and the 2.5 Revelation Barlow to work for you (with an actual mag nearer to 2.2x = 4.5mm equivalent eye piece)

The Taiwanese built Revelation Barlow appears to be the same as this Japanese one http://www.firstlightoptics.com/celestron-eyepieces/celestron-ultima-barlow.html 

The 2.5x barlow will reduce the focal point further into the tube by about 20mm - so you need enough travel adjustment there.

[Reeny]

Just read your other post, and realised that 4mm = 100x /and 4mm barlowed = 200x

You would need the 2.5x barlow and a 5x barlow.

That would be silly.

It would be better to get a 4.7x ES 82 degree from USA at £90 delivered, and barlow that

1.0x = 85x

Then: 2.0x = 170x / 2.2x = 187x / or 2.5x = 213x

Or for £22 plus £3 delivery - take a punt on the 4mm Revelation

[bomberbaz]

Hiya Reeny, not sure about your math there, but see the link. The scope I am looking at is this http://www.firstlightoptics.com/beginner-telescopes/skywatcher-heritage-100p-tabletop-dobsonian.html

So a 4mm is (400/4) = 100x and barlowed gives 200x 

[John]

A good one to look for would be one of the TMB Planetary eyepieces, either the Mk1 or the Mk II. They come in the 4mm focal length but have quite comfortable eye relief and a 58 degree field of view. I've seen them sell on the used market for less than £30. Might be worth a "wanted" advert ?

[bomberbaz]

Just found an advert for a 4mm tmb, fingers crossed its still for sale

[nightfisher]

reading this post, i found myself thinking a TMB might be the answer, also the TS HD ep`s seem pretty good

[michael.h.f.wilkinson]

I got a 4mm TMB-like EP for our kids' mini-Dob (F/4.3), sold as a 4mm UWA (60 deg FOR or so, 16mm eye relief), and it is a nifty liffle EP with sufficient eye relief for my kids (the eldest wears glasses, the youngest doesn't, but disliked the 6.3mm Plossl we have in their kit). I tried the 4mm in my APM 80mm on Jupiter at 120x, and it was very impressive for the money.

[bomberbaz]

great news I managed to get it. £30 delivered so cant be bad, happy enough with that i am