To answer your question briefly yes a slit lamp examination does reveal more than what meets the naked eye That said even a careful torchlight examination can help diagnose certain eye conditions 1- redness is in conjunctiva usually not cornea, generally yes trauma to the eye will have associated conjunctival redness called congestion 2- a 2 dimensional photo can only help in diagnosis if the condition is advanced or very obvious otherwise an actual physical examination always better 3- angles of the anterior segment (through which aqueous humor drains) can only be examined with Gonioscopy not otherwise due to a phenomenon called total internal reflection (requires a special instrument called gonioscope) 4- No but you can get an idea if there is severe narrowing of those channels by adjusting the torchlight sideways (only experts can comment not optometrists)

Hi... These are not yes or no answers ...inflammation in eye also is a broad term. For comprehensive exam..you need torch light, Slit lamp, gonio..n other thing as well. If you are having a doubt about someone's comment, examination.... Please go for a second opinion