义体人像最容易翻车的地方,往往不是机械件画得不够复杂,而是金属和皮肤之间那道接缝。接缝一旦处理成两块贴纸硬拼,整张图立刻退回塑料手办。下面这 10 条提示词围绕同一位女工程师展开,每条只改一处改造部位,把描写重心压在接缝过渡、金属表面处理和补光方式上。
先定规则:一次只动一处
把眼、颈、臂、腿全写进一条提示词,模型会把机械件均匀摊到全身,人物的脸被稀释,画面变成零件展示图。这组示例统一锁定一位三十岁上下的女工程师,短发、旧工装外套、无明显妆容,然后每条只指定一个改造点。人物不变,你才看得出到底是哪句话在起作用。
另一个常被忽略的点是改造的”理由”。写清接缝处皮肤有轻微肿胀、发红、被撑起的褶皱,观者会自动相信这件东西是装上去的,而不是画上去的。金属部分也别只写 metal,要写清是拉丝钛、抛光铬还是磨砂碳纤维,反光形态完全不同。
面部与颈部:接缝最藏不住的地方
脸和脖子是视线停留最久的区域,也是最容易露怯的地方。这一组四条从不同角度逼近接缝,用不同光型逼出金属边缘那一圈过渡。
01 · 左眼光学单元
Extreme close-up portrait of a [age]-year-old female engineer, left eye replaced by a brushed titanium optic with a thin amber iris ring, skin slightly swollen and pink where it meets the alloy, soft [light color] key light at forty-five degrees, matte charcoal backdrop, 85mm lens, shallow depth of field, visible pores怎么用:[age] 填具体年龄,[light color] 用 cold blue 或 warm amber。眼周必须写 swollen and pink,只写 mechanical eye 会得到一颗玻璃珠。光圈别开太大,接缝细节会被虚掉。
02 · 颈侧接口
Side profile of a female engineer with short dark hair, three recessed cable ports along the side of her neck, silicone-sheathed cables running under the collarbone skin, cool [light color] rim light tracing the jaw and shoulder, dark teal workshop behind, 50mm, medium shot, faint oil sheen on the metal怎么用:[light color] 建议 cyan 或冷白。侧逆光能让颈部轮廓和线缆分离开。坑在于线缆容易画成飘在皮肤外面,务必写 under the skin 或 entering the port。
03 · 前臂检修面板
Overhead shot of a female engineer's left forearm resting on a steel workbench, the forearm opened into a matte carbon-fiber panel with exposed servo tendons, skin edges taped and slightly red, warm [light color] task lamp from upper left, scattered screws and a caliper, 35mm, clinical realism, fine dust怎么用:俯拍加工作台是最好控构图的角度。[light color] 用 tungsten 暖光,和碳纤维的冷灰形成对比。别漏掉胶带和螺丝,这些杂物才是”正在维修”的证据。
04 · 指关节铰链
Macro shot of a female engineer's hand, two knuckles replaced by polished chrome joints with visible hinge pins, surrounding skin dry and faintly calloused, fingertip pressing a [tool] on a dark bench, single hard [light color] spot from above, deep shadows, 100mm macro, razor-thin focus plane怎么用:[tool] 换成螺丝刀、镊子或探针都行,给手一个动作比空摆着自然。[light color] 用中性白,硬光才有铬的锐利高光。微距下景深极浅,只保留一个关节在焦内。
肩背与躯干:大面积金属怎么不显假
面积一大,问题就从”接缝”变成”表面”。真实金属不会整片均匀反光,它有方向性的拉丝纹、有磕碰、有一层薄薄的油膜,这三样缺一样就会像塑料。
05 · 太阳穴到颧骨的钛板
Three-quarter portrait of a female engineer, a slim titanium plate tracing from temple to cheekbone, anchored by four small hex screws, fine scarring along the plate edge, backlit by [light color] haze so the rim separates from the background, 85mm, muted skin tones, realistic subsurface scattering怎么用:[light color] 选 dust orange 或 pale rose,逆光雾能把板材边缘勾出来。四颗螺丝是比例锚点,写清 small 才不会被画成大铆钉。皮肤要 muted,别让人脸抢过金属。
06 · 后颈脊柱外壳
Back view of a female engineer, hair shaved at the nape, a segmented spinal housing of dark gunmetal running from skull base to shoulder blades, each segment casting a thin shadow on the skin, [light color] practical light from a monitor below, dark room, 50mm, low-key, film grain怎么用:[light color] 用 monitor blue,从下方打光最像机房。重点是 each segment casting a shadow,有了段与段之间的投影,外壳才有厚度。低照度下容易糊成一团,加 film grain 反而稳住质感。
07 · 耳后折叠铰链
Extreme macro of the hinge behind a female engineer's ear, a brushed steel arm folding into a socket, skin stretched and slightly shiny where the implant lifts it, cold [light color] clinical light, sterile white background, 100mm macro, controlled speculars, hyper detailed texture怎么用:[light color] 用 clinical white,白底棚拍感最干净。皮肤被顶起的 stretched and shiny 是这个角度的关键,否则铰链像浮在耳后。speculars 要写 controlled,不然高光过曝。
08 · 左肩护甲与焊光
Medium wide shot of a female engineer in a dim workshop, left shoulder covered by a scuffed gunmetal pauldron bolted over a torn jacket sleeve, cables looping down her arm, [light color] light spilling from a welding arc off-frame, smoke haze, 35mm, cinematic composition, gritty realism怎么用:[light color] 填 electric blue 或 hot white。光源在画外比在画内更好用,写 off-frame 让模型自己推光影方向。烟尘必须有,它是把人物和环境缝在一起的胶水。
全身与环境:让义体落进具体场景
单看细节过关还不够,义体要成立,得有场景替它解释来源:谁装的、在哪装的、装了多久。最后两条把人物放进环境里,用环境光替金属做背书。
09 · 胸腹纵向接缝
Silhouette portrait of a female engineer, torso turned slightly, a vertical seam of pale alloy visible through the gap of an unbuttoned work shirt, [light color] light passing behind her so the seam glows at its edges, dust in the air, dark concrete wall, 85mm, high contrast, restrained color怎么用:[light color] 用 cold grey blue。剪影的关键是让接缝透光,写 glows at its edges 而不是整体发亮。色彩要 restrained,两三个色就够,多一个就散。
10 · 雨夜街头全身像
Full-body shot of a female engineer standing in light rain on a narrow street, mismatched implants at eye, neck and forearm catching [neon color] reflections, wet jacket clinging to the shoulder plate, puddles mirroring signage, 35mm, low angle, cinematic grade, realistic rain streaks怎么用:[neon color] 选 magenta 或 sodium orange,只留一个主色。低机位加湿地反光是赛博朋克的通用语法,但雨要写 light rain,暴雨会把细节全盖掉。这张适合当系列封面。
通用出图技巧
- 人物描述固定成一段可复用的前缀,只改改造部位那一句,这样十张图才像同一个人。
- 金属写三层:基底材质(brushed titanium)、表面状态(scuffed、oiled、dusted)、反光形态(specular、rim、diffuse),缺一层就发塑料。
- 接缝处一定要给生理反应:swollen、red、stretched、scarred,选一个就够,全写会变成伤口特写。
- 光比控制在柔光加一档轮廓光,义体人像不适合多灯,灯一多金属就变成镜面乱反射。
- 镜头别都用 85mm,特写用 85 到 100mm,半身用 50mm,全身用 35mm,焦距变化本身就是节奏。
- 负面词加上 plastic skin、toy figure、over-smooth、symmetrical face,能挡掉大部分手办感。
- 如果出图偏游戏 CG,补一句 film still, practical lighting,把质感往实拍拉。
- 同一部位至少出三版,只改光型不改描述,再挑接缝最自然的那张。
常见问题
问:为什么我写了很多机械细节,脸反而不像同一个人?
答:细节词会抢走模型的注意力预算。把人物特征写成固定前缀放在句首,机械描述压到一句,并只保留一个改造点,一致性会明显回来。
问:金属总是反光过曝,怎么办?
答:把 metal 换成具体材质名,再加 controlled speculars 或 matte finish,同时把主光改成柔光。镜面高光在低分辨率下会糊成一片白,反而丢失结构。
问:接缝看着还是像贴纸,有什么补救?
答:加三样东西:接缝旁的皮肤红肿、金属压出的浅坑、一小片阴影。这三样一起写,观者就会相信它有重量。
小结
义体人像的难点不在”多”,在”准”。一次只改一处,把预算全给接缝,剩下的交给光。想要更多同类题材,可以看赛博朋克提示词合集;如果还在搭整体世界观,AI 图片分类归档里也有场景与人像的分组,可以配合着用。
