Hypothesis: There is no difference between pentacam scheimpflug system and locs3 in grading of cataract.

Major aims:

1. research the efficiency of pentacam scheimpflug system in lens density measurment.
2. To compare the pentacam with the locs3 in grading of cataract.

Inclusion Criteria:

• cataract patient
• age>18

Exclusion Criteria:

• pregnant women
• any disease of the eye except for cataract
• patients who are ineligible by law to take decisions by themselves.patients who have a custodian.

catract patients who are coming for pre- surgical evaluation.