Canon 17-40mm f/4 L and/or Sigma 35mm f1.4 ART DG HSM-which should I buy?

Hi guys, please advise.

Currently using Canon 5D Mark ii and Canon 50mm 1.4 lens for portrait photography. However I'm looking to expand to doing indoor photography for restaurants and outdoor model pictures where I can get shots with bokeh as well as the subject and background in focus.

17-40mm and 35mm are both around $800/900 so my question is: do I get the multi-purpose zoom lens which can shoot wider and still include the 35mm I was looking for OR the prime lens which is exactly what I was looking for and is guaranteed to shoot fast and crisp shots?

I've read up on reviews from Ken Rockwell and watched reviews on YouTube and I'm having difficulty picking between the two choices: lens with options or lens that fills exact purpose.

Thank you all in advance for your suggestions

From what I know about interior photography, you will prefer the zoom lens, as 35mm isn't wide enough. I just read an article this morning about using a 16-35 for interiors - the manufacturer is different but the idea is the same, and you can see how useful the wide end is. You'll have to scroll down to see the interior shots:

The Sony 16-35 f/2.8 G Master Lens Review by Chad Wadsworth

I'd choose the zoom over the fast prime.

I use a 5DMkII and I have the: EF50/1.4; EF35/1.4L and EF16~35/2.8L MkII.

Between the two lenses that you mention, I suggest that you buy the 17 to 40/4L. Although the Sigma 35/1.4 is reportedly a excellent lens it is not wide enough for many of the shoots required to capture the aspects of the interiors of all restaurants that you'll encounter.

I don't know how much a refurbished EF 16~35/2.8L MkII would cost, but if that is within your budget, I agree it is well worth a look. The extra 1mm at the wide is noticeable and can be useful; the lack of 5mm at the long end is not such a big deal. The one extra Aperture Stop is quite handy to have up your sleeve, both for your background blur if using for it for Portraiture, (for example at 35mm), and also to convert to Shutter Speed and/or ISO, especially if shooting Hand Held in Low Level Light - though I expect for 'restaurant interiors', you'd normally have whatever lens you use, on a Tripod.

WW

For indoor interior shots, the slow wider lens and a tripod makes perfect sense.

For portraits, indoor and outdoor, a combination of a fast 35mm and 85mm would make a lot of sense (to me anyway).

No lens fills the exact purpose - which is why all the choice exist, and why zooms are so convenient. But it means you need to make clear choices: a very wide f/4 lens will do little with respect to shallow depth of field (and typically these lenses have less than stellar bokeh), and for portraits that may not be what you want. None of us can really tell you what best suits your needs. Where is the money? If the restaurant business is likely to be recurring business, you'll need the wider lens, clearly. If portraiture is the main business and the restaurants an occassional in between, consider renting the wide lens when needed, and build the correct lens set to do your main job.

Reasons to consider the Sigma 35mm f/1.4 DG HSM Art Canon-ef

Much wider aperture f/1.4 vs f/4. At its widest, the 35mm f/1.4 DG HSM Art Canon-ef captures much more light (3 f-stops)

Is a prime lens Yes vs No. Prime lenses have a single focal length, they are typically sharper and have wider apertures

Reasons to consider the Canon EF 17-40mm f/4L USM

Narrower aperture f/22 vs f/16. At its narrowest, the EF 17-40mm f/4L USM goes 0.9 f-stops narrower

More zoom 2.4x vs 1x. Around 2.5x more zoom, giving you more flexibility for photos

Slightly better wide angle 17 mm vs 35 mm. 2.1x better wide angle

Slightly lighter 475 g vs 0.7 kg . Around 30% lighter