Not so bad, how often written

Though Mirror Lens are often very poorly spoken, I have still a Walimex 500mm F8.0 bought.
I use a Samsung NX10 Mirrorless camera with APS-C sensor. An optical viewfinder is greatly obscured by panel 8, I care thanks to electronic viewfinder but little, the image is always set to the same brightness. That's why the first tip:
- Use Live View
In my mirrorless I can use it not only the display but also the viewfinder.

It continues with the focus. By design, there is no autofocus at a mirror telephoto. Actually come Mirror Tele from astronomy because an auto focus is even a hindrance. Tip:
- Live View with magnification for focusing

Would someone on the idea of ​​using a kilo heavy, 30cm long telephoto without a tripod? Hardly likely. But the sensational dimensions of a mirror Teles tempt. 350 gram, 7.5 cm diameter, 9cm length. Even my 135mm f2.8 is only marginally smaller and lighter. Tip:
- Stable tripod use

Pictures of Mirror Tele are generally low in contrast, and depending on the lighting conditions, the white balance is next. So you have to always sharpen, and possibly adjust the colors. After highlights are displayed outside the focal plane as circles that distract most, you should weaken this in a moment. Tip:
- Who sharp and crisp photos directly from the camera like, you can not use a Mirror Lens
- Always work with sunshade

On my camera I get to 770mm small picture focal length. So that I could depict a duck Full Frame from 20 meters. The picture I have reworked and shown an old school friend, who now works as a photographer with cameras like Canon 1Ds M3. He had only one complaint:
- The resolution of the lens is average
But he has not noticed that the picture was taken with a telephoto mirror.

Conclusion: Those who observe the special procedures for applying, gets a mirror telephoto a well-made lens with long focal length, small size, and good value for money.