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What you mean by too wide? It’s true field you are gaining and 2 deg field is a nice match to a Telrad as it matches the centre ring and you can get away without a finder. Power is low and sky brightness higher unless sky is very dark but for a few objects 2 deg is needed. I jump from Telrad to 41mm Panoptic giving 1.6 deg on my Newt and yearn for 2 deg but focal length of telescope doesn’t allow it. Same eyepiece on my TV-101 and I get 4.9 deg of flat field! Best for Sagittarius region.
I typically then jump to 20mm Type 5 Nagler and this is a very nice focal length for both 1640 focal length and 540mm focal length giving approx 1 deg and 3 deg respectively. Yes a 21mm Ethos would be fantastic here giving me 25% more true field.
Try Eta Carina at 2 deg with O-III filter. Wow! Veil nebula too requires low power and of course Pleiades is best at low power wide field over 2 deg. As a 30x /2 deg. finder though is what a 40mm would be best for but like I said in my previous post a 30mm would complement it. Dark skies are better for larger exit pupils to keep the background darker.
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