41mm Panoptic for 70mm televue refractor!!

[Eamo27]

My son wants a 41mm panoptic for the televue pronto he has. Does anyone think he is crazy, or is this a good combination??

[NGC 1502]

I have a TV Pronto, it's the F6.8 version (early Pronto's were F6.4).

The 41 Pan would give 12x mag, with a 5.8 degree field, wonderful for very low power wide field viewing. The only downside (apart from the cost) of that is the large exit pupil produced, almost 6 mm. Your son will probably have a dark adapted pupil larger than that, so no problem if you have a good dark observing site.

But for me, living under very light polluted skies, that very low power gives a washed out sky background, and my 65 year old eyes have a bit of astigmatism that is worse with large exit pupils.

So I use a 27mm Pan, to give 18x, 3.8 degree field, and an exit pupil of just under 4mm. The smaller exit pupil shows less astigmatism from my eyes, and the sky background is darker.

Maybe a 35mm Pan could be good for me as a compromise.

Hope that helps and gives you the info you need, regards, Ed.

[NGC 1502]

Sorry, forgot to say welcome to SGL Ed.

[Eamo27]

Great answer Ed. Yes, we are in the country, so skys are good. 35mm might be a better compromise, but I see a used one for sale at a discount.

BTW, so you have a pronto too? I have an eternal problem finding a decent mount. The one we have is a good camera mount, but hard to attach scope to head with a small thumb screw. Are there some sort of dovetail attachments I can get to allow for easy assembly? I know the ideal is the telepod head, but hard to get and expensive.

Thanks for welcoming me

[Stargazer_00]

Hi there. Some sort of dovetail + scope ring arrangement and then bolt it onto an AZ4 and you'll have an absolutely rock steady mount.

[umadog]

Might as well get binoculars instead.

[NGC 1502]

Great answer Ed. Yes, we are in the country, so skys are good. 35mm might be a better compromise, but I see a used one for sale at a discount.

BTW, so you have a pronto too? I have an eternal problem finding a decent mount. The one we have is a good camera mount, but hard to attach scope to head with a small thumb screw. Are there some sort of dovetail attachments I can get to allow for easy assembly? I know the ideal is the telepod head, but hard to get and expensive.

Thanks for welcoming me

There are several options for mounting a Pronto, I use an Astro-Tech Voyager alt-az. But this one is more widely available -

http://www.firstligh...a-ii-mount.html

You would also need a short dovetail for the Pronto's clamshell, to attach to the mount. The thread in the clamshell is the old 1/4 20, same as a standard tripod bush.

TeleVue do make an accessory dovetail for just that purpose, but I made my own from a standard skywatcher one, cut down to length.

This makes a great grab & go outfit, sets up in a jiffy, no hassle.

A previous poster mentioned binoculars, to some extent I would agree, but a properly mounted Pronto does so much more than binocs, from very low power wide field, up to sharp views of planets at 100-120x, a bit more on double stars, brighter DSOs, etc etc. Binocs cannot do such a wide range of viewing, but are stuck at low power only.

Regards, Ed.

Edit - here is the TeleVue accessory to attach to the clamshell for using the Pronto on the alt-az mount (part AVT-1011) But as I said, I made my own from a longer dovetail.

http://www.televue.com/engine/TV3b_page.asp?id=43