Head-to-head · used lens buying intelligence
Sony a7 IV: FE 24–105mm f/4 vs 24–70mm f/2.8 GM II — Used Lens Comparison
The Sony a7 IV deserves a standard zoom chosen around actual subjects, not a headline lens ranking. Sony's FE 24–105mm f/4 G OSS reaches farther and has optical stabilization; the FE 24–70mm f/2.8 GM II opens one stop wider and prioritizes fast, professional-standard coverage. Both support the full-frame E-mount sensor. Surprisingly, the brighter GM II is only modestly heavier by manufacturer specification. The differences that matter most are exposure, focal length, lens generation and the price and condition of an individual used copy.
Editorial research, not a claim of hands-on laboratory tests. We may earn a commission from qualifying retailer purchases at no extra cost to you.Which lens should you choose?
Choose the 24–105mm f/4 when daylight travel, portraits at varied distances and fewer lens swaps matter most. Choose the 24–70mm f/2.8 GM II for frequent indoor people and event work when its extra stop can preserve shutter speed. If most images are taken at 24–70mm in bright conditions, a large GM II premium may not return practical value. Neither lens replaces a long wildlife telephoto.
One-lens travel, daylight documentary photography and subjects where 70–105mm is useful.
Indoor weddings, event coverage and video assignments where f/2.8 and professional lens controls justify the cost.
Specifications that change the decision
Comparison at a glance
The specifications come from manufacturer documentation. They are provided for purchase decisions, not as invented sharpness, autofocus-speed or durability test scores.
| Consideration | Sony FE 24–105mm f/4 G OSS | Sony FE 24–70mm f/2.8 GM II | What it means |
|---|---|---|---|
| Full-frame mount | Sony FE / E mount | Sony FE / E mount | Both use the full a7 IV sensor; do not confuse these with APS-C-only E lenses. |
| Focal range | 24–105mm | 24–70mm | Both start at the same 24mm angle; the f/4 zoom extends 50% farther at the long end. |
| Maximum aperture | Constant f/4 | Constant f/2.8 | At matching shutter speed, f/2.8 allows twice the light of f/4, useful with moving subjects. |
| Manufacturer weight | 663g | 695g | Only 32g separates these two designs; physical size and bag space still differ. |
| Optical stabilization | Optical SteadyShot (OSS) | No lens OSS; a7 IV has IBIS | Stabilization helps camera shake, not the movement of a child or performer. |
| Filter thread | 77mm | 82mm | Existing polarizers and ND filters may require different sizes or adapter rings. |
| Closest focus / magnification | 0.38m / 0.31× | 0.21m (wide end) / up to 0.32× | Both focus relatively close for general zooms; neither is a dedicated 1:1 macro lens. |
Purchasing options · verified when available
Compare current used listings
Prices below apply to the specific eligible retailer offers, not every grade or copy of the lens. KEH prices are withheld if their independently monitored feed is stale; eBay listings must meet the recent-refresh requirement. Confirm shipping, returns, accessories and final stock with the merchant.
Sony FE 24-105mm f/4 G OSS Full-Frame Autofocus Lens for E-Mount
Currently eligible used purchasing options
Sony FE 24-70mm f/2.8 GM II Full-Frame Autofocus Lens for E-Mount
Currently eligible used purchasing options
Lowest tracked KEH offers: Sony FE 24–105mm f/4 G OSS: $711 (Bargain); Sony FE 24–70mm f/2.8 GM II: $2,195 (Excellent Plus). The listed-price difference is $1,484, but these may be different condition grades or include different accessories. It is not a like-for-like quality-adjusted saving. Check individual listing details and total checkout costs.
Editorial purchase analysis
Where the differences matter
When a one-stop advantage becomes a real photograph
At the same focal length and ISO, opening the lens from f/4 to f/2.8 lets you shorten shutter time by approximately half for a similar exposure. For a moving person this may be more useful than a stabilization claim. If a reception scene requires 1/60 second at f/4, f/2.8 could move it near 1/125 second under comparable light. This is an exposure illustration, not a promise of sharp photographs or equivalent optical performance.
The a7 IV includes body stabilization and the FE 24–105mm includes OSS. Those systems help reduce the impact of hand movement, but a dancer, child or athlete can still blur at a slow shutter speed. The GM II's f/2.8 advantage is meaningful most often when subjects move and lighting is poor. For static interiors on a tripod, f/2.8 may not be worth the additional used outlay.
The overlooked value of 70–105mm reach
Both designs begin at 24mm, so neither has a wide-angle framing advantage over the other. From the same position, a 105mm focal length gives significantly tighter framing than 70mm. It allows closer-looking travel details, compressed portrait backgrounds and medium-distance documentary images without swapping to a telephoto.
If you frequently shoot beyond 70mm on the a7 IV, the 24–105mm can replace an extra short-telephoto zoom in daylight. Conversely, wedding and portrait photographers may prefer to pair the GM II with a fast 85mm prime or a 70–200mm. Adding focal range and increasing aperture are competing priorities, not two interchangeable ways to get better photographs.
Buying used: lens generation and contents matter
Compare SEL24105G against SEL2470GM2 by the model codes printed on the lenses. Sony sold an earlier FE 24–70mm f/2.8 GM; used advertisements that omit 'II' can be significantly different products. Check exact pictures rather than assuming a search result for '24–70 GM' is the newer lens.
Inspect zoom smoothness, focus behavior, decentering symptoms, glass haze, lens contacts, exterior damage and the correct hood. Sony lists a 77mm thread on the f/4 zoom and 82mm on the GM II. Check whether the original hood and case are included, then compare the delivered price and the return window by individual condition grade. An apparently inexpensive GM II with optical issues is not a bargain.
Before you pay
Used-lens inspection checklist
- Read model codes: SEL24105G versus SEL2470GM2 (not the first-generation GM).
- Inspect AF, optical clarity, zoom movement, OSS where applicable and the exact condition grade.
- Check hood, caps, case, filter size and whether the merchant's photographs match the listed model.
- Decide whether indoor f/2.8 or 70–105mm reach solves the problem you encounter most frequently.
The exact model, optical condition, accessories, grade, warranty and seller return terms matter more than a small headline price difference. Read our complete used-lens buying guide.
Sources, methodology and verification
Mirrorless Lens World Editorial Desk reviewed this comparison on November 3, 2026, using the manufacturer documentation below and the site's native product-family catalog. Retailer data is refreshed separately. No original bench measurements or personal handling tests are claimed.
See our editorial policy and affiliate disclosure.
Frequently asked buying questions
Is the f/2.8 lens always heavier?
Sony lists the GM II at 695g versus 663g for the f/4 G OSS: a difference of only 32g. Physical dimensions and carrying requirements still matter.
Does stabilization make f/4 equivalent to f/2.8?
No. Stabilization reduces camera shake, but the f/2.8 maximum aperture allows more light for a faster shutter speed when a subject moves.
Is the 24–70 GM the same as the GM II?
No. Check the SEL2470GM2 model code. The earlier GM version is a separate optical and mechanical design.