BW-Optik 30 mm 80° via N31

last weekened I have had 4 days time to use the BW Optik 30 mm 80° in many diffrent telescopes.
My biggest priority was to see in which fast Dobs it is working fine enough

We used it in a 12"F/4 where the image was unacceptable
We used it in a F/5 Newtonian, where the edge correction was poor, but biggest part of the center very sharp
We used it in a 12"F/6 Dob where the overal images have been very good, even the outer edge was not bad

The image of the 30 mm BW in the 12"F/6 was at the edge about same sharp as the tele Vue Nagler 31 mm showed in the 12"F/4

The most interested result was when we compared the BW 30 against other chinese and Taiwanese 2" eyepieces , the center sharpness in the BW was superior to alöl his competitions which cost about same and partly more money

In my TMB 115F/7 the BW also performed very well for the biggest part of the field

So I think the BW 30 is very good to use in all SCT, MCT, Refractors down to F/7 and Newtonians down to F/6

if your system is faster you may think about the Naglers

best wishes

Markus

Good evening, Markus:

Do you recommend getting or not getting the BW-Optik 30mmm 80 for a F/6 achromat, in particularly the Burgess 102 F6? If you recommend not getting it, what 2" low power (30-40mm) eyepiece in this price range would you recommend?

I bought a Burgess 102 F6 and am looking for a few extra eyepieces. Following some strong recommendations, I was looking for a 2" wide field eyepiece. I was close to deciding for the BW-Optik 30mm 80 when I read where you recommend it for refractors at F/7 or higher. That has given me pause since the Burgess 1026, although with a very good lens (based on prototype reviews), is a F/6 achromat.

Thanks, and good evening.

Mark Costello

I have both the BW-Optik 30 mm and the Proxima GTO 31 mm 71 degree eyepiece. A couple of nights ago I had the opportunity to test them in both my OPT Star Hunter 10 inch F5 DOB and my Pronto.

My impressions:

Both eyepieces seemed to be similarly sharp in the center in both scopes. The Proxima had better edge correction in both scopes.

I think the critical distinction here is whether stars near the edge of the FOV are distracting and take away from the overall aesthetics of the view. In the 10 inch F5 scope, brighter field stars were somewhat distracting in the BW-Optik eyepiece whereas most views in the Proxima were not objectionable. The same was true to a smaller extent in the Pronto. Both worked well for galaxy hunting.

The BW-Optik did have a larger FOV but not a great deal larger, what was at the edge with the BW-Optik was just outside the FOV with the Proxima and with a slight nudge, it was there. And in a fast scope, I would say the Proxima definitely had a wider pleasant/useable FOV.

The Proxima requires a great deal of back focus, the eyepiece was barely engaged in order to achieve focus in the DOB. The Proxima is also significantly lighter than the BW-Optik.

I have tried the BW-Optik in my 12.5 inch F4.1 Discovery DOB and it is definitely not pleasing. I have not had the opportunity to use the Proxima yet.

For terrestrial viewing in the Pronto, the BW-Optik is a definite winner. It seems reasonably sharp to the edge (the edge is not distracting)and provides a 5 degree FOV at 16X.

My next move is to put a 2 inch focuser on my 8 inch F6 Orion XT-8, I think that with a 5 mm exit pupil, these eyepieces will be plenty bright and given what Markes has said about F6 Newtonians and the BW-Optik, the view should be quite pleasing.

One issue here is that the BW-Optik is a $95 eyepiece while the Proxima GTO is a $150 eyepiece. I bought my GTO via Astromart but here is my thinking. I think that the GTO is worth a try for someone who owns the standard 10 inch F5 DOB and is interested in some reasonable wide field views. I would try to buy it with the option to return it if one is not satisfied, these seem to go for about $80 on Astromart and that is quite a loss if one is not satisfied.

jon