Sigma's modern design is based around building affordable lenses with high optical quality, with size taking a lower priority to the former two points. One of the lenses that most obviously embodies this is the 40mm f/1.4 Art. This great video review takes a look at this humongous but impressive lens.
Coming to you from Dustin Abbott, this excellent video review takes a look at the Sigma 40mm f/1.4 DG HSM Art lens. Personally, I absolutely love my 105mm f/1.4 Art. It is a massive lens, but the image quality I get from it is astounding, and it was quite affordable compared to similar lenses, and because of that, I am more than willing to hoist it around. The 40mm follows in the those same footsteps and offers a unique focal length that some photographers and videographers find intriguing. Altogether, if you do not mind the extra size and weight, it looks like a great option. Check out the video above for the first half of Abbott's thoughts.
You can watch part two of the review below:
Do you own the 40mm f/1.4 Art? Would you shoot with such a large lens if you were guaranteed such high image quality?
I stopped buying Sigma lenses when I discovered they are unnecessarily big while also having poor light transmission or T-stops not very close to their F-stop's. For example I used to own their 85mm f1.4 Art, which yes is extremely sharp and not a bad lens, but has a T-stop of 1.8! So it's bigger than Nikon's 85mm f1.4G and sharper in the center, but it has poor light transmission while also being annoyingly large. I know there is a difference between what an F-stop is and what a T-stop is so give me a break, I know what I'm trying to say is somewhat foolish. However the fact remains that Sigma makes enormously huge center sharp lenses that have poor light transmission due to optical design of over design. Most off their lenses suffer from field curvature, which is basically being very sharp in the center but having poor mid and corner sharpness as the cost of super center sharpness. Most people don't seem to know or care about anything I am saying and I know people will hate me for saying anything against Sigma, because they wan't to validate their own purchasing decisions. So have at me, but do your research first please.
Preach on Reverand. No matter how you cut it, look at it, or sniff it. A light in the wilderness. People want to rave let thsm and smile. I am reminded of Sigma's crown the 1980's 35-70 zoom master. They even got the push-pull backwards. Want a sharp 40. Konica Hexanon 40mm 1:1.7 AR
This guy doesn't know what he's talking about.
Field curvature? Field curvature is when sharpness is uneven in a bowl/donut shaped manner. Sharp in the middle and far corners but not in the middle thirds. If you tweak the focus for more even sharpness across the frame then the middle is not at maximum sharpness, that's field curvature. As far as I know, among the primes, that applies to only Sigma 18mm 1.8 ART. Nikon's 28mm 1.8G has a similar issue. Every lens is sharp in the middle and then slowly drops in sharpness off the to sides. That applies to every lens.
Why do you care about T stop? Is a lower light transmission of anywhere from 1/3rd to 2/3rd of a stop such a big deal if you are not doing videos with the lens? Are you shooting portraits at Iso 6400 or something?
Sigma is the camera company I respect the most. Fully family owned. And everything they make, is 100% domestically sourced. Every single component in their products, are Made in Japan. They don't outsource just for the sake of cost cutting or cheaper labor unlike larger companies, yet are able to undercut first party lenses in pricing.
Ummmm. Curvature is distortion that can be influenced by individual lens shapes and defects with that shape in the element. Elements are basically convex or concave, constructed in groups in a simple lens design. It can be controlled to an extent by the use of exotic non traditional element design. I am not delving into flat field lenses. If you have a lens that is sharp in the center, softens then goes sharp again in corners you have something going on with that lens that is way beyond curvature. Curvature is not controllable in normal lens by tweaking focus. You have to have either have a tilt shift design, or a lens mounted to a lens board with swing adjustments, ala view cameras where you can manipulate both tilt and shift of the lens board axis and film plane axis ( both X an Y axis) in the back. Fisheyes on the other hand rely on this curvature.
Hate to break it to you but without T stops you would not have F stops. T stops are a more accurate way to gauge true light transmission than F stops. And a better indicator of the quality of light transmission. They are so important that Zeiss includes them on lenses that are mounted on Hasselblad cameras. And I would be willing to say outclass any lens that Sigma or any manufacturer has produced. They went too the Moon if I remember correctly. Also F and T are not the only stops there are others, all equally important. If you like Sigma and they work for you great, you saved a buck. I never found that the case for me. Their history is not of a quality lens manufacturer, but of a low cost consumer lens. And also. I am looking at a Sigma 35-70 1:2.6-2.8 ZoomMaster push/pull in Nikon F AI mount (1980's) with Taiwan engraved on the bottom of the barrel. That I pulled out the drawer on my work bench. Got it at a flea market in OEM box with instructions warranty card, and card of manufacturer authenticity.
Well I may not have said it as well as an expert in optical engineering and I thought field curvature was the proper term for Sigma's design goal. Either way all you have done is try to tear my comment apart on possible error in wording, although I clearly described what I meant afterwards. You can argue for Sigma all you want, but everything I said is true even if not in the right technical wording. I'm not an optical engineer or lens designer, obviously but I know enough about lenses to know Sigma has only one goal and thats center sharpness at all costs. As far as me, yes I'm constantly shooting at ISO 6400-12800, because I'm a photojournalists and therefor T-stop value/stated F-stop theoretical value is important to me, nothing to do with video. The only reason I brought up Sigma's having poor light transmission is because they are massive, yet fair worse than smaller competitors in T-stop values. Maybe I'm not the person to properly describe the issues Sigma's tend to all have, but I promise you someone can. In fact the guy who responded to your reply seems pretty good at it. All you're adding to the mix is you're apparent love or admiration for Sigma Art lenses, probably because you own one. We all watch review videos of products we already just bought to make ourselves feel better about our choices and financial decisions, me included. I get that you like Sigma and you are a fan of their's and thats great. I'm happy that other people buy things that make them happy. At the end of the day all that matters is that you're happy, but that does not negate the facts I have put forth. I didn't even bring up build quality, weather sealing and life span on Sigma like I would have 5-10 years ago, because seemingly all have improved, but prices have risen so they should have improved. If I'm perfectly honest I'm not one hundred percent against third party, I like the new Tamron 35mm f1.4 USD so much I want it badly and the Sigma 40mm Art seems tempting as well. Tamron and Sigma threw everything they had both of those lenses resepctively and it shows what they are currently capable of when they go all out. The only reason I'm not leaning towards the Sigma 40mm f1.4 Art over the Tamron is for the reasons and suspicions I listed above now twice. The size compared to their actual transmission value is laughable, but sharpness is impressive I will say that. Again though the falloff is greater and overall they are not as sharp across the frame in many cases when you take corner, mid frame and center sharpness into account versus first party. They are always the sharpest lens only in the center, not overall across the entire frame and I thought that meant field curvature, so sorry if I misspoke.
if you are looking at 3rd party primes. Check out Tokina Opera line. Smaller in class than others. Sharp as hell and with a extremely close T-F stop transmission ratio. Even light transmission across the board. They drew on their cine division, which is an industry leader, in designing this series. Metal construction throughout. USM AF drive. weather sealed, Low Flare with hood. Good colour repo and saturation. Only drawback price is more than Tammy/Sigs and they still used that damn AF/MF clutch. Don't own one, and not an endorsement in any way. But it can hold its own with them all. Saw some prints from a friend I trust and was impressed with outcome.
I'll check them out, but honestly I'm pretty sure about the Tamron 35mm f1.4 USD that recently came out and have already sold my Nikon 35mm f1.4G to fund it. I prefer primes but only own three and the new Nikon 70-200mm f2.8 FL, which actually performs like a prime. It's extremely impressive what Nikon was able to create with that lens even though it was $2800 when I bought it. I have a 400mm f2.8 VR that use a lot too for my work, but at the wide end I really do prefer primes over the Nikon 24-70mm f2.8 options. Not that those are bad, they just can't compete with primes and I prefer to either zoom with my feet or switch to DX camera's to cover the difference. I have a 24mm f1.4G and the 35mm I am trying to replace, don't really like any of the 50mm lenses except the 58mm f1.4G from Nikon, but I already had one and sold it as it was too close to 70-200mm length and not much better than the new 70-200mm FL even when stopped down to f2.8!
Ok was just a suggestion nothing else. I am good friend wth the person who repairs my cameras. Just realize there still is alot of plastics in questionable places and communition problems with certain bodies lens combos though more in Canon than Nikon according to him.
Lol you sound like me through 3 format sizes from Large to Medium to 35 small I own 2 zooms. I shoot primes. In 35mm I do have 3 Zeiss CZ the 35 50 Planer & 85 CZ. That the closet I get to 3rd party . Am still rocking halite and MF. No Digital or AF. Lol to me IBIS & VR is hold your camera steady . Blows the new generations mind.
The T Stop of the 85mm 1.4 Art is not 1.8. It is 1.5. Not sure where you're getting your information from. The 85mm Sigma Cine FF Prime lens is the 85mm Art lens that's been rehoused for cinema use. Optically, the glass is the exact same as the Art. That lens is rated at a T 1.5... https://www.bhphotovideo.com/c/product/1527871-REG/sigma_32m974_85mm_t1_...