Baader Hyperion 8mm bottom section

[Red Dwarfer]

Hello everyone , 

Does anyone know what focal length you get when you screw off the bottom 1.25 section of the Baader Hyperion 8mm ? Maybe somewhere between 14 and 18mm ? 

I got it yesterday included in the extras with a SW 80ED , along with a SW 2" super deluxe barlow and the 28mm 2" LER kit lens .

 

[MARS1960]

There is a spec sheet on RVO that might help, bottom of page.

http://www.rothervalleyoptics.co.uk/baader-hyperion-1252-modular-eyepiece.html

[John]

I tried this once. I seemed to recall that I got something around 22mm with the bottom section removed. It was rather poorly corrected though so I didn't use it that way.

 

[Red Dwarfer]

1 hour ago, MARS1960 said:

There is a spec sheet on RVO that might help, bottom of page.

http://www.rothervalleyoptics.co.uk/baader-hyperion-1252-modular-eyepiece.html

Many thanks for the link , the chart gives two results of 21.8 and 30.0 . I think the first one is the best answer . I was trying some terrestrial tests with the adjusted 21.8 Baader and 28mm LER on red berries in a hedgerow - the famous berry nebula ?

[Red Dwarfer]

12 minutes ago, John said:

I tried this once. I seemed to recall that I got something around 22mm with the bottom section removed. It was rather poorly corrected though so I didn't use it that way.

 

Thanks for the response . 22mm sounds about right and I did notice a barrelling ( if that is the right term ) effect to begin with but when I leaned right in it was gone . It's an interesting feature , but I'm not sure how keen users would be unscrewing lens elements in the dark ?

 

[John]

If you want to use the Baader Fine Tuning Rings then you have to unscrew the nose piece because the rings fit in between that and the main eyepiece body. The optics in the nose piece do more than just creating the focal length which is why the optical performance of the top section alone is not too good.

Baader's modular approach to their stuff does give you plenty of options to explore though

[LukeSkywatcher]

I know if you unscrew the bottom of a 2x barlow that you get something like 1.5x. Ive never heard of anyone doing the same with an EP to increase/decrease the magnification. Maybe i'm reading this thread the wrong way.

[John]

8 minutes ago, LukeSkywatcher said:

I know if you unscrew the bottom of a 2x barlow that you get something like 1.5x. Ive never heard of anyone doing the same with an EP to increase/decrease the magnification. Maybe i'm reading this thread the wrong way.

 

[LukeSkywatcher]

A couple of yrs ago i bought the Baader Hyperion 8-24mm zoom. To this day, i still dont know what most of the parts are for. Something to do with 2" to 1.25" conversion and nose pieces for imaging.

[Red Dwarfer]

2 hours ago, LukeSkywatcher said:

I know if you unscrew the bottom of a 2x barlow that you get something like 1.5x. Ive never heard of anyone doing the same with an EP to increase/decrease the magnification. Maybe i'm reading this thread the wrong way.

I`d never heard of them neither until yesterday . Baader seem to be the only brand to do this modular design as well 

[John]

Moving the position of the lens element of the barlow lens away from the eyepiece increases the amplification factor while reducing the separation, reduces it. There are quite a few brands of barlow that have removable lenes element sections but Baader seem to take the modular approach much further than most. Meade used to make a barlow with a sliding optical element so you could vary the amplification. Basically a zoom eyepiece works on this principle.

 

[Louis D]

Then there are the Speer-Waler 5-8mm and 8-12mm "zooms".  They're more accurately described as varifocal.  I have the original 5-8mm version, and it is actually quite good.  Coupled with an 8-24mm zoom and a lowest power, widest field eyepiece, I'm pretty well set for compact travel.

There was also the Zoomset for inserting between the positive and negative parts of some eyepieces.