Both lenses are excellent; the 85mm f/1.4G gives the smoothest bokeh and the shallowest depth of field, while the 85mm f/1.8G delivers nearly the same image quality for far less weight and cost—choose the f/1.4 for ultimate portrait look, the f/1.8 for value and portability.

Quick guide

• Key considerations: bokeh quality, wide‑open sharpness, autofocus speed/noise, weight, and budget.
• Clarifying questions: Do you shoot mostly tight portraits or environmental headshots? Do you need the absolute shallowest DOF or a lighter, quieter lens for long sessions?
• Decision points: Pick 85mm f/1.4G if you prioritise creamy bokeh and maximum subject separation; pick 85mm f/1.8G if you want excellent optics, lower weight, and better value.

Comparison table

Attribute	85mm f/1.8G	85mm f/1.4G
Max aperture	f/1.8	f/1.4
Typical weight	Lighter; easy to carry	Heavier; more substantial
Bokeh	Smooth, very good	Creamier, more painterly
Sharpness (stopped down)	Excellent	Excellent
AF speed/noise	Fast and quiet (AF‑S)	Good, depends on generation
Best use	Everyday portraits, events	High‑end portraits, editorial work

Optical performance

Sharpness: Both lenses become very sharp by f/2.8–f/4; the D800/D810 will reveal differences, so technique matters. Wide open the f/1.4G can deliver a softer, more painterly look that many portraitists prize, while the f/1.8G tends to be a touch crisper and more forgiving wide open. Bokeh and rendering: the f/1.4G generally produces smoother highlight roll‑off and creamier backgrounds, but the f/1.8G renders pleasing, natural separation at a fraction of the cost.

Autofocus, handling, and build

AF system: Both are AF‑S designs (built‑in motor) and work well on modern Nikon bodies; the f/1.8G is typically lighter and quieter, making it easier for long handheld sessions. Build and balance: the f/1.4G often feels more substantial and better balanced on larger bodies, which some photographers prefer for controlled portrait work.

Price, value, and real‑world use

Cost vs benefit: The f/1.4G commands a premium for its shallow DOF and build; the f/1.8G is widely praised as an excellent value that covers 90–95% of real‑world portrait needs. For event shooters or photographers who carry a kit all day, the f/1.8G often wins on practicality and ROI.

Risks, trade‑offs, and actionable steps

• Risk: Buying the f/1.4G for its shallow DOF can lead to missed shots due to narrow focus; Action: practice precise focus, use single‑point AF or back‑button AF, and stop down when needed.
• Trade‑off: Heavier kit vs subtle image nuance; Action: rent or test both on your body to judge real differences in your workflow.
• Budget risk: Paying for marginal gains; Action: if you shoot long sessions or need portability, favour the f/1.8G for the best cost‑to‑performance ratio.

Recommendation

If you want the ultimate portrait look and can live with extra weight and cost, choose the 85mm f/1.4G. If you want nearly identical image quality with lower weight and much better value, choose the 85mm f/1.8G.