A few years late for a comment, but if you have the tools available, I would check if the rear mirror is over-tightened. Once I loosened the back mirror of my lens and tightened it just where the spring engaged the mirror, the lens I have got an increase in sharpness. It appears that in factory the assembly was over-tightened on my lens, causing the rear mirror to deform ever so slightly, which decreased sharpness.
for a low price is it a good lens. I have sony 70 -210 the price 2000 Euro. When i bay i prime 300 i think 8000 euro en 600mm about 15000 euro. Yes the are better. But i can't and will not pay that price. And the mirror have a fast apature and a small range. When you make photo's not full open then correct it the lens ferry fast. A have a look whits the 70-210 F2.8 and the minilota 70-300mm APO. The last is cheaper about 1/4 off the price. Now i whill not more use it. Only problem the wegt off 1,5 Kg.
A few years late for a comment, but if you have the tools available, I would check if the rear mirror is over-tightened.
Once I loosened the back mirror of my lens and tightened it just where the spring engaged the mirror, the lens I have got an increase in sharpness.
It appears that in factory the assembly was over-tightened on my lens, causing the rear mirror to deform ever so slightly, which decreased sharpness.
Good invention for lense like that is a remote
Oh thank you that's answer need 500 and 1000 these lenses because nature from different eyes is changing 🙂
for a low price is it a good lens. I have sony 70 -210 the price 2000 Euro. When i bay i prime 300 i think 8000 euro en 600mm about 15000 euro. Yes the are better. But i can't and will not pay that price. And the mirror have a fast apature and a small range. When you make photo's not full open then correct it the lens ferry fast. A have a look whits the 70-210 F2.8 and the minilota 70-300mm APO. The last is cheaper about 1/4 off the price. Now i whill not more use it. Only problem the wegt off 1,5 Kg.
MTO lens needs temperature equalisation. It must be the same temperature as the environment you're using it in. If it is not, MTO loses sharpness.
Interesting. Do you mean the lens should be ~1h outside of the bag, if used outside?
Have you had stabilisation in the camra body ?
No, there was no stabilation in the camera body