Reticle Eyepiece

[Deadlake]

Looking for a reticle eye piece to use in a finder with a 90 degree erecting prism.

I like either Vixen and Tak reticle eyepieces but they don’t make 90 degree finders.

I  have an APM reticle EP, but to me the cross hairs are a little fuzzy compared with the Vixen finder scope.

The other option is the Baader finder, but wondering what other options there are?

Anyone used any of these:

https://www.apm-telescopes.de/en/optical-accessories/eyepieces/reticle--astrometric-eyepieces/apm-reticle-eyepiece-20-mm-70-1.25.html

 

https://www.baader-planetarium.co.uk/shop/baader-polaris-i-25mm-t-2-illuminated-measuring-and-guiding-eyepiece/

 

Edited December 9, 2020 by Deadlake

[michael.h.f.wilkinson]

12 hours ago, Deadlake said:

Looking for a reticle eye piece to use in a finder with a 90 degree erecting prism.

I like either Vixen and Tak reticle eyepieces but they don’t make 90 degree finders.

I  have an APM reticle EP, but to me the cross hairs are a little fuzzy compared with the Vixen finder scope.

The other option is the Baader finder, but wondering what other options there are?

 

 

If your APM eyepiece is this one:

https://www.apm-telescopes.de/en/optical-accessories/eyepieces/reticle--astrometric-eyepieces/apm-reticle-eyepiece-20-mm-70-1.25.html

it is possible to get the reticle in sharp focus by twisting the rubber ring. I have a similar one, which worked fine, until I replaced it by a home-made solution

 

[Captain Scarlet]

13 hours ago, Deadlake said:

I  have an APM reticle EP, but to me the cross hairs are a little fuzzy compared with the Vixen finder scope.

That is actually a feature not a bug. That rubber ring allows you independently to focus the eyepiece onto the reticule, then adjust the focus of the objective until the stars are sharp. That way the stars and the reticule are at focus in the same focal plane. If the stars are sharp and the reticule fuzzy, they are in different focal planes and you’ll get parallax, ie the cross-hair point moves around the star-field as you move your eye. I have an APM finder/ eyepiece and it’s very good. The SW-style ones that come with many scopes don’t easily allow one to make those adjustments.

Cheers Magnus

[Deadlake]

2 hours ago, Captain Magenta said:

That is actually a feature not a bug. That rubber ring allows you independently to focus the eyepiece onto the reticule, then adjust the focus of the objective until the stars are sharp. That way the stars and the reticule are at focus in the same focal plane. If the stars are sharp and the reticule fuzzy, they are in different focal planes and you’ll get parallax, ie the cross-hair point moves around the star-field as you move your eye. I have an APM finder/ eyepiece and it’s very good. The SW-style ones that come with many scopes don’t easily allow one to make those adjustments.

Cheers Magnus

Cheers. I didn't notice that. Will try it out when the weather clears.

Having said that, the Baader is meant to be a step up on the APM from some one who owns one, this one:

https://www.baader-planetarium.co.uk/shop/baader-polaris-i-25mm-t-2-illuminated-measuring-and-guiding-eyepiece/

 

[Louis D]

The 20mm reticle is sharp in the center but miserable in the outer 50%.  It's probably a König design variant if I had to guess.  I've got the Orion version.  See below for a comparison image through it:

[bomberbaz]

I really like the APM reticle eyepiece, gives me just over 4 degrees through my 80mm finderscope which works really well with a telrad. 

I know it wasn't the tightest at the outer edges but it's used as a finder, so not a main eyepiece.

A lot going for me with this eyepiece along with the good FOV  plus lower magnification compared to some IR/EP's there is very decent eye relief. 

Oh and I didn't actually know about the tuneable recticle but it hasn't actually ever been a problem, haha. 

Edited December 9, 2020 by bomberbaz