|
I tried the 7mm in the 12" at f/5. Seeing was not up to it at all, but as far as I could tell it does very well at f/5. Just a bit of colour on Jupiter very close to the edge of field. Similar to f/6 from memory.
The thing that is by far the biggest letdown with the EP IMO is the FOV. It feels more like a Plossl than a widefield and excludes it from being a DSO EP for me. The 60 degree FOV of XF and Radian feel nice and wide enough for very enjoyable DSO observing (10 degrees extra from the XW is a nice bonus but I don't miss it terribly when it's gone). But the Burgess definitely gives a more cramped feeling on DSOs. I suppose it's an individual thing. My threshold for what I call widefield seems to be at around one radian = 57 degrees.
Looking through the EPs at a white wall I compared the FOV with the Antares Elite 15mm (spec 52 degrees) and the Pentax XF. The Burgess seems to be between these two, but a bit closer to the XF, I guess maybe 56 or 57 degrees.
Another thing I noticed (looking at the white wall) is that with Pentaxes and the Elite, the view past the field stop is pitch black. In the Burgess you can see the inside of the barrel somewhat. I suppose that accounts for the extra scatter I saw last night on Jupiter and the Moon.
|