
Sony A6700 + Sigma 17-40mm + 70-350mm contre Sony A7C II + Sigma 28-70mm
Hello everyone,
I’m a former Sony A7 IV user. I used to own the Sigma 85mm DG DN Art and the Sigma 24–70mm DG DN Art which I had to sell mainly for financial reasons. I was extremely satisfied with that setup.
A few weeks ago, I had the opportunity to buy a brand-new Sony A6700 with the Sony 70–350mm. I’m planning to add the Sigma 17-40mm f/1.8 DC Art. I previously owned the Sigma 28–50mm f/2.8 and was a bit disappointed with it. It was good for the price and weight, but I found it somewhat lacking in terms of sharpness and especially micro-contrast. The Sigma 17–40mm seems to be on a completely different level, although it costs around €1,000.
That said, I still have a few days left to return the A6700, and I’m considering switching to a Sony A7C II with the Sigma 28–70mm f/2.8 DG DN Contemporary, since adding the Sigma 17–40mm f/1.8 to my current setup would increase the total cost significantly anyway, given that this lens alone costs around €1,000.
With the A6700, I can’t seem to achieve the same “wow” effect I had with the A7 IV, or even with my previous full-frame cameras from other brands. It’s difficult to define exactly, but I feel like I’m missing pure sharpness and a certain sense of “depth” in the image.
I really love the size and form factor of the A6700 even more than the A7 IV and I also love its autofocus, which the A7C II shares. However, I’m a bit disappointed because the A6700 seems to get noisy fairly quickly at higher ISO values (which is expected with APS-C), and overall I feel the image rendering is not quite as good. That said, perhaps the Sigma 17–40mm would improve this significantly.
My main question is:
Would a Sony A7C II with the Sigma 28–70mm produce noticeably better image quality than a Sony A6700 with the Sigma 17–40mm? For roughly €200 more, I would lose the 70–350mm but gain a full-frame setup. I’m struggling to determine whether the image quality difference I’m noticing is mainly due to the larger sensor and higher effective resolution, or if it’s mostly because I’m currently using a less capable lens.
I’d really appreciate any advice or firsthand experience.
Thanks!