here is my presentation for all, I hope heartily (!) that someone will enjoy in this hobby, it's easier than a beginner can consider

1. Body Lens

2. 50 mm focallenght

3. 100 mm focallenght

4. Large aperture lens Short depthoffield Lensdiameter Aperture value (2, 4, 5.6..) = Focallenght Exposuretime light on sensor = Small aperture lens Long depthoffield (Aperture value)2

5. Minimum aperture value (f/32) Exposure 15 s (!) maxdepthoffield

6. Very low aperture value (f/22) Exposure 8 s Verylargedepthoffield

7. Low aperture value (f/14) Exposure 3.2 s Largedepthoffield

8. Medium aperture value (f/8) Exposure 1 s intermediate depthoffield

9. Large aperture value (f/5.6) Exposure 0.5 s short depthoffield

10. Verylarge aperture value (f/3.5) Exposure 0.2 s Very short depthoffield

11. Max aperture value (f/2.8) Exposure 0.125 s Minimum depthoffield