Digital camera sensors have shown amazing advancements in just the past few years to a point where APS and even smaller sized sensors are more than adequate to produce professionally usable images. One thing that has not kept pace with this advance is the availability of APS lenses that are similar in terms of quality, and fast aperture speed, to what we find for full frame models.  Specifically, I am talking about the short to medium zoom in the 24-70mm f/2.8 range along with a long tele zoom similar to a 70-200mm f/2.8. These two lenses are the mainstay zooms of most pros. The focal lengths have been available for APS cameras, but not coupled with fixed, fast apertures. I never could figure out why the top camera makers were not producing something like a 50-150mm f/2.8, which would be roughly equivalent to a full frame 70-200mm.

Finally a lens manufacturer has decided to fill the gap. Sigma has come along and addressed this issue with two fast, fixed aperture zooms in a variety of camera mounts, including Nikon DX. If they are as good as they appear to be, they may for the basis for a top notch profession camera kit in DX format.

The Sigma 18-35mm f/1.8 zoom lens mounted on a Nikon D7100 with the Sigma 50-150mm f/2.8 zoom and Nikon D5300 nearby.

The shorter zoom is an 18-35mm (28-50 full frame equivalent), which is a bit smaller than the typical 24-70mm zoom range that has become the medium range staple of full frame cameras. However, the Sigma lens has an unusually fast and fixed f/1.8 aperture making it exceptionally handy for the range it does cover.

Sigma's other APS zoom is a 50-150mm f/2.8 which is equivalent to 75-225mm in full frame, pretty much the perfect size and aperture for a standard long zoom.

Both lenses are part of Sigma's new Art series intended for high end use by being better made with quality optics. While both lenses are a bit on the heavy side for what is normally associated with an APS sensor camera, they are heavier due to their large apertures, which is the whole point of these lenses, and they are still considerably lighter than their full frame equivalents. These lenses are intended to fill a gap in the APS camera range by supplying more professionally suitable optics to photographers who want to use this smaller camera format.

Photographed with a Nikon D7100 and Sigma 50-150mm f/2.8 zoom lens. 

To my way of thinking, these two zooms could form the base outfit for a professional APS camera system. Couple them with a Nikon D7100 or even the D5300, add a macro like the 40mm, and one of the Nikon wide angle zooms, and you're ready to go - a lighter and smaller than normal system capable of top level results.

The Sigma 18-35mm seems to be able to come in closer that other lenses I have used in this zoom category.

I will be testing and reporting on each of these lenses separately over the next week. In addition, I will be testing the new Nikon D5300, and posting my reviews on this blog.

I have already had some time to play with these lenses on the two Nikon cameras I mentioned and have been favorably impressed thus far. I suspect that if anyone is looking for a really top notch, pro outfit in the DX format, these two lenses may be the cornerstone to achieving it.