SEL1855 (E 18-55mm F3.5-5.6 OSS)
4-6
Fig.4-5-1
266.5 mm
200
mm
4-5. RESOLVING POWER CHECK/ADJUSTMENT
Tools and Equipments
• Resolving power check chart (Note)
* Download the resolving power check chart from the TISS homepage.
• Camera (NEX-5)
Note:
Prepare the resolving power check chart according to the procedure shown below.
1. Download the [Focus-Chart_A3.pdf] from TISS homepage.
2. Print the [Focus-Chart_A3.pdf] sized by 100%.
4-5-1. Preparations
1. Set the Shooting Mode to the Aperture Priority mode and set the f-stop value to the minimum (open).
2. Set the camera at a shooting distance of 1400 mm (imager surface) and set the zoom at the TELE end.
3. Focus to make the chart aligned equally in all directions.
4-5-2. Resolving Power (Partial blur) Check
1. Set to manual focus on status that the “4-5-1. Preparations” condition.
2. Focus and shoot with self timer.
3. Keep focusing as step 2, change the object distance to 1300 mm and 1500 mm, then shoot two times with self timer.
4. Check the three images to see if the resolution of the patterns in four corners meets the standard shown in Fig.4-5-2.
NOTE:
Check if the patterns on the four corners are visually as the same resolution.
*
Use Adobe PhotoShop to check the image resolution.
Fig.4-5-2
Near the limit
*
Check the five patterns in center and four corners at the same magnification.
OK
OK
NG
NG or out of focus
1 Group Lens Assy
1 Group Moving Frame
4-5-3. Projective Resolving Power (Partial Blur) Adjustment
1. Turn the 1st Group Lens Assy to adjust the partial blur.
If partial blur is still not improved after the 1st Group Lens Assy is turned, replace the 1 Group Block Assy.
2. Perform the check and adjustment repeatedly until the partial blur is resolved.
NOTE:
If the partial blur cannot be resolved even after the adjustment, replace the parts in the order shown below.
1) 2 Group Frame Assy
2) 3 Group Frame Assy
* If the partial blur cannot be resolved even after replacing the parts 1) and 2), replace the Service Exclusive Optics Block.
