Sigma
BF
Minimalist full-frame L-mount body with large top screen and unique design.
$1,999
Released Apr 2024
Sony
Alpha 7 IV
33MP hybrid all-rounder with 10-bit 4K 60p and AI-powered subject tracking.
$2,499
Released Oct 2021
BF is 2.5 years newer.
Wins
BF
Wins
Alpha 7 IV
5 categories tied
TL;DR — Key differences
- BAlpha 7 IV has higher AF points / zones (759 vs 49)
- BAlpha 7 IV has higher RAW buffer depth (828 frames vs 60 frames)
- BAlpha 7 IV has higher Max video bit rate (600 Mbps vs 150 Mbps)
- BAlpha 7 IV has higher ISO max (native) (51,200 vs 25,600)
- BAlpha 7 IV has higher Burst (mechanical) (10 fps vs 6 fps)
Key specs at a glance
Size and weight, to scale
BF
138 × 98 × 88 mm
720 g (1.59 lb / 25.40 oz)
Alpha 7 IV
131 × 96 × 80 mm
658 g (1.45 lb / 23.21 oz)
BF is 7mm wider, 2mm taller, and 8mm thicker than Alpha 7 IV.
BF is 62 g heavier than Alpha 7 IV.
Depth (front-to-back): 88mm BF · 80mm Alpha 7 IV
Sensor size, to scale
BF
36 × 24 mm · Full Frame
864 mm² area
Alpha 7 IV
35.9 × 23.9 mm · Full Frame
858 mm² area
Lens ecosystem
Native lens selection
BF: mount data unavailable
Alpha 7 IV
✓ more lensesSony E
350+
native lenses available
Counts include current first-party and major third-party native autofocus lenses.
Use-case scoring
Which one for what?
Algorithmic scores from verified specs · 10 = best in class
Why pick one over the other
Reasons to choose
BF
AF low-light limit
-5 EV vs -4 EV — lower is better
Dimensions (W×H×D mm)
Adds 138, 98, 88
Pre-Capture / Pre-Release
Only BF supports it
Burst (electronic)
15 fps vs 10 fps — higher is better
Subject recognition
Adds Vehicle
Battery life (CIPA)
640 shots vs 580 shots — higher is better
IBIS effectiveness
6 stops vs 5.5 stops — higher is better
Reasons to choose
Alpha 7 IV
Dimensions (W×H×D mm)
Adds 131.3, 96.4, 79.8
AF points / zones
759 vs 49 — higher is better
RAW buffer depth
828 frames vs 60 frames — higher is better
Max video bit rate
600 Mbps vs 150 Mbps — higher is better
Codecs
Adds XAVC HS, XAVC S, XAVC S-I
ISO max (native)
51,200 vs 25,600 — higher is better
Subject recognition
Adds Insect, Car/Train, Airplane
Internal RAW video
Only Alpha 7 IV supports it
Both cameras share
- ✓AA filter — Both support aa filter
- ✓ISO min (native) — Both 100
- ✓Eye AF — Both support eye af
- ✓Animal / bird AF — Both support animal / bird af
- ✓4K max frame rate — Both 60 fps
- ✓In-body stabilization — Both support in-body stabilization
Pros & cons at a glance
Editorially curated highlights and trade-offs.
BF
Pros
- ✓Unique design
- ✓Full-frame
- ✓L-mount
Cons
- –No IBIS
- –Niche ergonomics
- –Limited controls
Alpha 7 IV
Pros
- ✓33MP — more detail for cropping and print
- ✓10-bit 4K 60p (Super35 crop) / 4K 30p full-frame
- ✓Full-size HDMI port
- ✓759 phase-detect AF points
Cons
- –4K 60p requires Super35 crop
- –10fps burst lags behind R6 II at 40fps
- –Complex menu system
Full specifications
✓ = category winner
Frequently asked
Quick answers generated from verified specs.
Which is better for vlogging, BF or Alpha 7 IV?
Alpha 7 IV scores 8.0/10 versus 5.5/10 for BF — Fully articulating screen — see yourself while filming.
What's the resolution difference between the BF and Alpha 7 IV?
BF is 24.2 MP and Alpha 7 IV is 33 MP, so the Alpha 7 IV captures more detail for cropping and large prints.
Do the BF and Alpha 7 IV have in-body image stabilization?
BF has 6-stop in-body image stabilization, while alpha 7 IV has 5.5-stop in-body image stabilization.
Which shoots faster bursts — the BF or the Alpha 7 IV?
BF reaches 15 fps electronic. Alpha 7 IV reaches 10 fps electronic.
What's the weight difference between the BF and Alpha 7 IV?
BF weighs 720 g and Alpha 7 IV weighs 658 g, so the Alpha 7 IV is 62 g lighter.
Do the BF and Alpha 7 IV record 4K video?
BF: 4K up to 60p. Alpha 7 IV: 4K up to 60p.
Are the BF and Alpha 7 IV weather sealed?
BF: Yes. Alpha 7 IV: Yes.
Which has better battery life?
Rated battery life is 640 shots (CIPA) for the BF and 580 shots for the Alpha 7 IV, giving the BF the edge.
How much does each cost?
BF launched at $1,999 and Alpha 7 IV at $2,499. The BF is $500 less.
Specs sourced from manufacturer data. Use-case scores algorithmically derived. Last reviewed May 2026.
Product images courtesy of Sigma and Sony press materials.