Unverified80% confidenceCautionTime unknown
仅拍风光/建筑不建议购买70-200 f/2.8：风光多用小光圈且很少需要浅景深，f/4甚至变焦比更大的24-105更实用且更轻
1
Sources
80%
Confidence
Long-term
Relevance
-
First Seen
Sources
Related Entities
Related Claims
Unverified只在阳光充足白天拍摄的普通爱好者不建议买f/2.8恒定光圈重炮，重量翻倍且价格高数倍，白天缩光圈到f/5.6时与廉价镜头画质差距被拉平71% similarUnverified老机身或入门机身对焦系统弱时，不建议买f/8光圈的廉价超长焦，弱光和f/8下对焦会明显拉风箱，需确认机身对焦点在f/8下可用71% similarUnverified不建议为省钱买f/6.3以上小光圈超远摄变焦（如150-600mm廉价款）用于运动/鸟类连拍，暗光下对焦拉不动且快门速度受限，容易全程废片71% similarUnverified单套重量轻、价格极低，作为辅助被动反光装饰性价比高，但反光亮度远不如大面积轮圈反光贴或主动发光灯条71% similarUnverified外景补光不建议只买单只小面板灯，户外阳光下小灯功率被压制几乎无效，需≥60W带聚光反光碗的灯或多灯组合70% similar
Cite This Claim
Stable URI
https://kongchang.com/claim/223892API
curl https://kongchang.com/api/v1/knowledge/claims/223892MCP
get_claim(id=223892)