mayoayo
Well-known member
I have been able to finally test the Baader Zoom,after many years wanting to try this eyepiece.A broken/stuck unit was given to me by a good friend (thanks Isra)a few days ago.This is the Mark III and for what i have been reading ,quite a few units have suffered this problem,..Apparenty the grease around the barlow dries ,becoming almost like adhesive and totally freezing zoom operation.Luckily the internet offered also testimony from users that managed to fix this ,and a nice explanation with pictures helped me to take apart the eyepiece and easily return the zoom to normal operation.This was a very simple thing to do,so no need to be impressed with my skills.:smoke:..Anyway...After the eyepiece was fixed, I went on with the second part of the project,.modification to fit the Kowa 823..A fast test had already revealed that the zoom didnt reach infinity on the kowa.
Without some sort of modification the eyepiece sits too high on the scope,and is not able to focus past 20-30 meters.The shame of this fact is that the Hyperion adapter to fit the 2 inch astro tube,DOES fit the threads of the kowa eyepiece cover,providing a beautiful,secure attachment..Really the perfect fit,..but at the expense of infinity focus...I have read on this Forum a review of the Zoom ,being used on the Pentax 65 after removing the ring that fits the rotatory collar.This ring is the cause of the Zoom not reaching infinity on most scopes,for it rises the eyepiece almost 5 mm above most mounts.This might not seem much ,but on the Kowa 823 makes a difference of not focussing past 30 m to pass infinity focus for about 5 diopters.
I removed the ring using a pair of needle point pliers,..it was fairly easy after i wrapped an old bicycle tire around the collar ,for a secure grip...
Once the ring is out, the eyepiece does work beautifully at all focal lenghts.Due to the shape and size of both the zoom and the scope,s mount, there is little room for improvising or inventing a mean of attach the zoom..I either need a new ring or perhaps new threads machined to the original ring...Either way would be worth the investment ,because optically this combo is very good...nice wide angle views once you past 16mm..(more or less 30x)..At
The lowest power,24mm ,it grants about 18x,but the FOV is narrow still,and besides showing quite a lot of vignetting,i see some edge blurring..At the 20mm mark there is no vignetting and the edge performance is much better,but the AFOV still feels a bit narrow more typical of a zoom .It is though about the same field of view now at 20mm that at 24mm,so the FOV is widenning clearly...And then at the mid of its range the zoom really becomes wide , close to the 16 mm mark...More like the the views granted by fix power eyepieces. Quite a treat..Excellent contrast and sharpness all the way to 56x .I saw a bit of lateral color at 56x,around the edge,in the form of a bit of a purple fringe,but the fluorite objective keeps the center of the image really clean of any CA..So im pretty happy with this combo..I really needed this eyepiece and I am happy that it is possible to make it work..Now i need to have the adapter made,but It is going to be quite easy...
Without some sort of modification the eyepiece sits too high on the scope,and is not able to focus past 20-30 meters.The shame of this fact is that the Hyperion adapter to fit the 2 inch astro tube,DOES fit the threads of the kowa eyepiece cover,providing a beautiful,secure attachment..Really the perfect fit,..but at the expense of infinity focus...I have read on this Forum a review of the Zoom ,being used on the Pentax 65 after removing the ring that fits the rotatory collar.This ring is the cause of the Zoom not reaching infinity on most scopes,for it rises the eyepiece almost 5 mm above most mounts.This might not seem much ,but on the Kowa 823 makes a difference of not focussing past 30 m to pass infinity focus for about 5 diopters.
I removed the ring using a pair of needle point pliers,..it was fairly easy after i wrapped an old bicycle tire around the collar ,for a secure grip...
Once the ring is out, the eyepiece does work beautifully at all focal lenghts.Due to the shape and size of both the zoom and the scope,s mount, there is little room for improvising or inventing a mean of attach the zoom..I either need a new ring or perhaps new threads machined to the original ring...Either way would be worth the investment ,because optically this combo is very good...nice wide angle views once you past 16mm..(more or less 30x)..At
The lowest power,24mm ,it grants about 18x,but the FOV is narrow still,and besides showing quite a lot of vignetting,i see some edge blurring..At the 20mm mark there is no vignetting and the edge performance is much better,but the AFOV still feels a bit narrow more typical of a zoom .It is though about the same field of view now at 20mm that at 24mm,so the FOV is widenning clearly...And then at the mid of its range the zoom really becomes wide , close to the 16 mm mark...More like the the views granted by fix power eyepieces. Quite a treat..Excellent contrast and sharpness all the way to 56x .I saw a bit of lateral color at 56x,around the edge,in the form of a bit of a purple fringe,but the fluorite objective keeps the center of the image really clean of any CA..So im pretty happy with this combo..I really needed this eyepiece and I am happy that it is possible to make it work..Now i need to have the adapter made,but It is going to be quite easy...
