18 replies to this topic

[William Lewis]

Hello. I have a small favour to ask.

I use a televue 60 with a 24 pan and 9mm type 6 with it mainly but am looking for slightly more magnification for the moon and planets. I would like to add the baader classic ortho 6mm but don't want to have to adjust the drawtube element of the focuser to use it when swapping from the televue group b eyepieces (all my eyepieces are group b). If anyone happens to have a the bco 6mm could they see if it's reasonably parfocal with group b, i.e pan 24, nag type 6, TV plossls from 32 down etc?

Any help greatly appreciated!

Thanks in advance.

Will

[deSitter]

Hello. I have a small favour to ask.

I use a televue 60 with a 24 pan and 9mm type 6 with it mainly but am looking for slightly more magnification for the moon and planets. I would like to add the baader classic ortho 6mm but don't want to have to adjust the drawtube element of the focuser to use it when swapping from the televue group b eyepieces (all my eyepieces are group b). If anyone happens to have a the bco 6mm could they see if it's reasonably parfocal with group b, i.e pan 24, nag type 6, TV plossls from 32 down etc?

Any help greatly appreciated!

Thanks in advance.

Will

 

I would get an Ortho from the classic era. Vixen, University Optics, Meade RG etc. You can even get an 0.965" 6mm Ortho and buy a cheap adapter to 1.25". But 1.25" Orthos are easy to find. These are very likely to be better than the Baader offering.

 

-drl

[azure1961p]

Why wouldn't a Baader classic ortho be as good as any UO, Vixen or the like?  Ones I used had 50° fov which was the only thing I didn't like.  The extra fov wasn't sharp near the fields top.  But once past that it was a good ortho indeed.

 

Pete

[William Lewis]

Thank you both. Neither of you would happen to have one still lying around with any televue group b's would you? I did consult the eyepiece buying guide (excellent) but the focal point wasn't mentioned.

[William Lewis]

Having done a little further reading my understanding is that televue group b eyepieces have there focal plane 6.35mm below the shoulder. Baader list the 6mm bco as having 10.2mm of eyepiece body above the reference plane but it doesn't mention where the focal plane is in relation to the reference plane.
I have read that baader's standard is to have the focal plane at the shoulder meaning that it would be in range of my helical focused but would still like a definite answer if anyone has the relevant eyepiece to hand, i.e a baader classic ortho and any group b televue eyepieces.

Edited by William Lewis, 01 May 2025 - 10:22 AM.

[Mike W]

Why not a 7mm Delite? It's a "B".

Edited by Mike W, 01 May 2025 - 11:45 AM.

[William Lewis]

Hi Mike.

I'd like something a little smaller than the delite. The 9mm type 6 only just fits in the tv60 case, 7mm or more likely 5mm delites are a bit too long unfortunately. Ideally I'd like room for a few filters that currently reside in the 3rd eyepiece cut out. I could thread them all onto the end of a nice small ortho.

Thanks for the suggestion though.

Edited by William Lewis, 01 May 2025 - 12:54 PM.

[deSitter]

Thank you both. Neither of you would happen to have one still lying around with any televue group b's would you? I did consult the eyepiece buying guide (excellent) but the focal point wasn't mentioned.

 

No, in fact I'm alawys on the lookout for Orthos Put in a request in the "Looking For Odds & Ends" section of the Classics forum. The old eyepieces will invariably be well made and good to excellent optically, and cheap. The 6mm Ortho is one of the most common formats.

 

-drl

[William Lewis]

I do like plossl's and there Matsuyama brethren but the mop and tpl's share a similar focal plane which is nowhere near group b unfortunately, I have an mop 12.5mm and 20,15 and 11 TV plossls and a 2.5x powermate for most of my planetary use with different scopes but the 2.5x powermate is way too big for the case and the 11 or 8 televues don't give quite enough mag - with the televue 60's 360mm focal length every millimeter counts!

[Mike W]

Volcano top for limited E/R? Or better yet an SVbony 3-8mm zoom, TV 3-6 zoom is "B"

 

https://www.bing.com...2ac&ntb=1&ntb=1

Edited by Mike W, 01 May 2025 - 02:28 PM.

[William Lewis]

Hi Mike

I'm not a big fan of zooms. Illogical I know but changing eyepieces, their different characters in terms of field of view, curvature, light throughout and colour is something I enjoy when I'm observing.

I only generally have 3 with me depending on what I'm doing. I see a few decent looking ortho's about and have no problem with an older one.

Im sorry if Im coming across as pedantic but getting something relatively close to parfocal with my other eyepieces when I'm using the the TV 60 just means a lot less faff when changing eyepieces.

I think the focal plane in relation to the shoulder of the eyepiece is the number one stat every eyepiece should list but doesnt, knowing it makes for a much easier life purchasing and using eyepieces.

Edited by William Lewis, 01 May 2025 - 04:39 PM.

[William Lewis]

I've talked to my usual retailer the wide-screen centre in the UK and they can supply a baader 1.25 eyepiece tube extension as well as parfocalising rings so whatever the situation I should be able to make it work, it might even breathe new life into my largely unused Matsuyama 12.5mm mop if I can make that a little more parfocal too.

Thanks again.

Will

[jrmacl]

No, in fact I'm alawys on the lookout for Orthos Put in a request in the "Looking For Odds & Ends" section of the Classics forum. The old eyepieces will invariably be well made and good to excellent optically, and cheap. The 6mm Ortho is one of the most common formats.

 

-drl

Did you see the TELE VUE Ortho OR. 9mm 0.965" Reticle Eyepiece that 25585 just posted:

 

https://www.cloudyni...early-tele-vue/

[vtornado]

I had the Baader 6 BCO,  I thought it was a good eyepiece for lunar/planetary.  It does have tight eye relief.  Which means it is easy to fog in the winter, and its easy to get eye lash grease on it.   I don't have any TV equipment to compare the focal plane with.

 

Have you thought about a para focal ring?

[deSitter]

Did you see the TELE VUE Ortho OR. 9mm 0.965" Reticle Eyepiece that 25585 just posted:

 

https://www.cloudyni...early-tele-vue/

 

I wouldn't accept that if it were free No love lost for "Tele Vue" here.

 

-drl

[jrmacl]

I wouldn't accept that if it were free No love lost for "Tele Vue" here.

 

-drl

still as far as "odds and ends" go it is very rare and unusual, I've never seen one

[deSitter]

still as far as "odds and ends" go it is very rare and unusual, I've never seen one

 

It's just a standard Japanese Ortho from the day, probably like most of them very good. I'm sure the accoutrements (illuminator and reticle) are also from the day. IOW this thing was 100 percent imported.

 

Here it is in the 1985 Carton catalog.

 

-drl

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[jrmacl]

I think unless you can get your hands on some Zeiss, aren't they all pretty much "standard Japanese Orthos", I just never saw a TV ortho before. But yeah, even if it is rare, it's just a standard ortho at the end of the day.

[davidgmd]

I wouldn't accept that if it were free No love lost for "Tele Vue" here.

 

-drl

  
Well, since it’s a Carton I guess you could own one without having to feel too hypocritical.