 A fast 14mm lens is a classic for capturing the Milky Way for good reason. It's about as wide as you can go without going fisheye. Because 14mm is so wide, it's also a very creative focal length for combining the Milky Way with foreground elements, as I did in this photo, where I had the arch of the Milky Way hug the outline of that tree. There are many choices for 14mm lenses, but I picked three that I felt covered the gamut when it comes to budget. From this Samyang F2.8, which is currently available at $249 US, to the Rokinon SP F2.4 at $699 US, and finally the Sigma Art F1.8 at $1,599 US. Hi, my name is Nico Carver, I'm a Deep Sky photographer, and with this review, let me start with a few disclosures. The Samyang I bought myself for the purpose of this review with proceeds from my Patreon, the Rokinon SP I rented from LensRentals.com, and the Sigma Art Lens was lent to me by my favorite camera store, Hunts Photo & Video. A huge thank you to Gary Farber and Noah Buchanan at Hunts for supporting this channel. And if you're interested in the Sigma Art Lens, you can reach out to Noah Buchanan at Hunts for special pricing. Just let Noah know that Nico sent you. All three of these lenses feature non-removable tulip style lens hoods. And this is typical of wide angle lenses. It's not my favorite. I should note that you have to be careful when using a dew heater strap with these style of lens hoods, as it's very easy to accidentally block light and add vignetting if the dew heater strip rides up a little bit too much. And so for this reason, when I use a dew heater strip with these lenses, I wrap it around the focus ring, and I find that you still get a little bit of heat on the front glass element that way, and it works to prevent the lens from fogging up. There's not a huge difference in the length of these lenses, but they do get a little bit longer as they go up in price. There's a much bigger difference in weight. They should all still be okay on most star trackers, but the Sigma especially would probably require the use of a counterweight kit to really get the most out of the tracking. In the end, the main thing we're looking for in an astrophotography lens, no matter what the focal length, is how well does it perform on the stars. And stars are called point sources, and they're one of the most challenging performance tests for a lens, as they can show off many flaws of a lens, like chromatic aberration, chromatic aberration, and field distortions away from center. The night sky also really shows vignetting, and modern lenses will often have corrections that you can turn on. You can either turn these on inside the camera, or if you shoot raw afterwards with a raw converter in post-processing, and these corrections will fix some of the problems. I find the automatic corrections help a lot with vignetting. One quick note about vignetting, if you're planning to just do a single shot of the Milky Way, I think the best is just turn on the automatic correction in camera if you have that, or the next best would be turn it, you know, remember to use it in post. If you're planning to stack and do all that work, you might want to look into flat fielding. Now, one reason I don't like the tulip lens hoods is because they're very hard to flat field, because you can't just put something flat on top here, it will never work correctly, so you really have to do sky flats. So the automatic lens corrections for vignetting actually might be a good idea with lenses this wide, and the truth is with lenses this wide, I often don't do full calibration, I just shoot the lights and turn on these auto corrections. Okay, so let's take a look at how these lenses perform on the night sky, and then I'll give a little commentary about what I think. Before we jump into the test images, let me just quickly put up this slide for anyone interested in how I do this lens testing. To summarize it quickly, I use trapped single exposures, and the only setting I change on the camera between the exposures is aperture and exposure time, so that we can see the effect that stopping down the lens has on the stars, while keeping the brightness of the photos fairly consistent between these different exposures. I also try to work in the middle of a moonless night when the sky is darkest and work as fast as possible so that the environmental conditions are roughly the same. Alright, starting with the Samyang 14mm f2.8, this is also sold under the brand name Rokinon. I bought the Samyang version as it was a bit cheaper. It's a fully manual lens with a click stop aperture ring to control the iris. At f2.8 there is a lot of vignetting and no corrections in camera, this is being a fully manual lens, but you can correct it in a raw processor on your computer pretty well. Interestingly, the vignetting is still quite noticeable even at f5.6 without corrections. It's pretty soft, meaning that there's a lot of coma, even in the center of frame at f2.8, that coma is basically sort of everywhere. But as you can see, it sharpens up very nicely at f4. I was actually surprised how well it cleaned up at f4, and it's even better at f5.6, but not quite as big a jump from f2.8 to f4. Camera performance is soft with elongated stars as expected, but I've definitely seen worse and not much chromatic aberration at any aperture. The Rokinon SP 14mm f2.4, just like with the last lens, this lens is also sold as the Samyang, but the Samyang version is called the Samyang XP 14mm f2.4. The lens has an electronically controlled iris, and it can do 3rd and half stops as well as full stops. The focus is still manual only. Vignetting is not quite as bad as the last lens, and it's pretty much gone by f5.6. The lens is just a tad soft, wide open, but I'd say definitely usable. Stopped down just a tiny bit to f2.8. Star shapes in the corners are pretty decent at any aperture, but corner sharpness improves greatly at f4. And lastly we have the Sigma ART 14mm f1.8. This lens has electronic iris control and also has autofocus. It's quite big and heavy. Vignetting is not bad at f1.8 or f2.5, but miraculously gone by f4. You can also use corrections in camera or later on the computer to correct vignetting. The center sharpness is what blew me away about this lens. It's nearly as good wide open as it is at any other aperture. Corner performance though is a different story with pretty bad astigmatism until we get to around f3.5 or f4. While the astigmatism is pretty bad, corner sharpness is still excellent with a lot of really fine small stars. Alright, so now the head to head. Let's first look at center crops. At f2.8 the Rokinon SP is passable, but the Sigma ART is the clear winner. And what's amazing to me about the Sigma ART is that at f1.8 it still wins against any of the others at f2.8. At f4 they all look much closer and I'd say these are all acceptable at f4. But the Rokinon SP is caught up to the Sigma when the Sigma is used wide open. So let that sink in. The Sigma at f1.8 is about as sharp as the Rokinon SP is at f4. With the corner crops I'd say the Rokinon SP wins at f2.8 due to the Sigma's astigmatism. The Sigma still looks a bit sharper and brighter than the competition. And at f4 the Rokinon SP and the Sigma are pretty evenly matched while the Samyang is noticeably softer at f4. Alright, here's a summary slide. Basically the Samyang 14mm f2.8 is a good deal if you're willing to use it at f4. The Rokinon SP 2.4 is quite usable at f2.8 or 3.2. Even the Sigma art only has the flaw of astigmatism in the corners when used faster than f4. But sharpness is amazing even wide open with the Sigma. So if I had to pick one to use without a tracker just using a tripod packing light I'd pick the Sigma and use it at f2 or f2.2. Speaking of which I did just that and shot untracked and came up with this photo with the Sigma. This was 355 8 second photos at f2 just on a tripod. And next week I'm going to share my stack for this photo and post a tutorial where you can process this photo along with me in Photoshop. So look out for that next week. So who do you think won this battle? Is the high price of the Sigma worth it? Well let me know in the comments what you think and until next time this has been Nico Carver from NebulaFotos.com. Clear skies everyone.