Dear Dan, I'm sure you probably learned and know much more than me. But I just know my camera, and it happens to be a Shen-Hao, and I know how it was designed. Maybe you right about the manufacturer, how designed the camera with Fresnel and sells it as an option, but I'm not a manufacturer, I'm a user and I have to follow manufacturer. And if manufacturer wants me to pay more for the Fresnel, I pay more, because I want to have Fresnel on my camera. The question was about how to install Fresnel on the Shen-Hao, and I gave the detailed answer, and even more, gave some explanations to the others why it is this way and not the other because the camera has a place where the Fresnel shall go. I don’t see that anybody except me gave the same detailed answer or even mention that he knows that particular camera and how it’s made. I did best what I can. All other posts in that treat are just about general camera design and construction and knowledge of all of us. And we all are right, we all know that the ground glass shall not to be moved if we like to have a sharp pictures. And believe me or not it will not be moved, because the Shen-Hao designed this way. To follow my recommendation or not this is another question and let the person why ask the question decided. I just did my best. Thank you.