I was recently at Mono Lake, California, one of my favorite locations. And of course, I was using my Opticron MM4 60 trying to scope the birds on the lake.
As I mounted it on the tripod and had a look, I almost had a fit: I thought my scope had broken. I could not focus on the birds, nor on the tufa formations; it was as if there was a smear around everything, especially around anything bright. This was quite different from the atmospheric turbulence to which I am used; also, it was a windy day, so there was no hot air pooling above the lake. It was more of a double-image-like effect.
After returning from my trip, I tested the scope, and it's fine, it is its usual super-sharp. Evidently, there was some interesting refraction phenomenon over the waters of the lake that caused the halos.
This made me realize that I probably don't need a scope of more than 60mm. The conditions in which I observe are rarely ideal; it is rare that I can truly use 40x; my most commonly used magnification is probably around 25x. I live in California, where the sun tends to be strong and cause heating effects that degrade sharpness. The only time I truly appreciated (someone else's) 60x was in an early December morning, spotting hawks sitting on trees from hilltops (we could survey huge regions with the scope for a bird count).
For you birders in other world regions, do you find magnifications greater than 40x often useful?
I need to return to Mono lake during breeding season...
Enjoy your scopes, you all!
As I mounted it on the tripod and had a look, I almost had a fit: I thought my scope had broken. I could not focus on the birds, nor on the tufa formations; it was as if there was a smear around everything, especially around anything bright. This was quite different from the atmospheric turbulence to which I am used; also, it was a windy day, so there was no hot air pooling above the lake. It was more of a double-image-like effect.
After returning from my trip, I tested the scope, and it's fine, it is its usual super-sharp. Evidently, there was some interesting refraction phenomenon over the waters of the lake that caused the halos.
This made me realize that I probably don't need a scope of more than 60mm. The conditions in which I observe are rarely ideal; it is rare that I can truly use 40x; my most commonly used magnification is probably around 25x. I live in California, where the sun tends to be strong and cause heating effects that degrade sharpness. The only time I truly appreciated (someone else's) 60x was in an early December morning, spotting hawks sitting on trees from hilltops (we could survey huge regions with the scope for a bird count).
For you birders in other world regions, do you find magnifications greater than 40x often useful?
I need to return to Mono lake during breeding season...
Enjoy your scopes, you all!
