[lytrytyr]

Equivalence basically says that a given parameter < t, d, FoV, #MP > defines an image completely, that all images shot using this parameter are indistinguishable. So, two different choices of parameters aren't equivalent.

Many thanks for the clarification.

It was the second sentence in the quote,
the other half of the story,
which wasn't apparent from the "White Paper."

[Edgar_in_Indy]

I was thinking about it, and despite its larger-than-normal size, this new 18-35mm has the potential to lighten my load and simplify the process of deciding which lenses to carry with me. Here's why.

Whenever possible, I like to go with my small camera bag, which means one lens on my camera and one other in the bag. In the past I've frequently found myself unable to decide between my 10-20mm and 30mm 1.4 to accompany my longer 85mm 1.4 or 50-150mm 2.8, and wishing I could take both my wide angle and my fast standard to accompany my telephoto. When I can't make up my mind, or think I might need both, then I end up taking a larger bag and more lenses, which means more weight and more lens swaps.

Now, I'm thinking that in a lot of cases this 18-35mm 1.8 can take the place of both my 10-20mm and my 30mm 1.4, as long as I don't need an extreme wide angle. So I could see myself frequently going with the 18-35mm 1.8, along with either the 85mm 1.4 or the 50-150mm 2.8 depending on what I'm doing. So with just two lenses I've got a wide angle, a fast standard, and a fast telephoto.

In fact, I might go ahead and sell my 10-20mm to help finance the 18-35mm, since I've been wanting to get an 8-16mm eventually anyway. And the 8-16mm will also pair better with the 18-35mm. At least until Sigma comes out with a 10-18mm f2.8 lens.

It also occurs to me that the 18-35mm 1.8 also has the potential to replace my 30mm 1.4, but I'll probably hold onto it since I like it so much, it's not very expensive, and sometimes I like to go with just the 30mm since it's small and light.

[EarlVonTapia]

Great lens, insanely amazing price!

I thought about whether I would, at some point in time, want to get this lens as an upgrade to my current lens for this "range" (a Tamron 17-50).

Right now, the answer is no. A couple of main reasons:

- This lens is quite heavy. It's more or less comparable to the weight of the DA*50-135. Carrying one around for a while is already tiring enough. Carrying two? I'm not so keen on that. It could work if you're in a setting where you can set a camera/lens down for a while, but as a walkaround say on vacation or a casual setting, I don't think so.
- Also, people are paranoid enough these days about big lenses on the street, and the trend seems to be for pocketable discrete cameras for that kind of thing (Fuji, Sony, Ricoh GR). As for those "everyday moments", well I got a Q so I didn't have to lug my K30 to dinners and whatnot. I think a big lens like this could be kind of obnoxious for that sort of thing.
- It's range is small. I find myself shooting at either the wide end (17-20mm) or 50mm. Only sometimes in between. While the difference between 17mm and 18mm is negligible, I think I'll miss that extra reach at the long end quite a bit.

The f1.8 is nice though, and at that price it's absolutely amazing. It certainly makes buying a DA*16-50 at brand new prices seem kind of foolish. But I think the Sigma 18-35 will be a specialist lens for more creative purposes or for use in a more controlled environment (wedding or studio perhaps?). I don't think it will outright replace general zooms like the 17-50's or the 17-70's. Rather, for those who have a tighter set of demands, this will provide them with options.

Of course I'm not expert so I could be totally off, but that's what I got. So I'm going to wait until the dust settles and the "wow new thing!" factor dies down a bit before decided whether to pursue this lens down the road.

All that being said, this lens at this price can only lead to good things. Hopefully other people in the camera game will push back with their own attractive offers.

[lytrytyr]

I've been wanting to get an 8-16mm eventually anyway.

Don't wait too long:

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/107090-sigma-8...ml#post2420603


(Apparently discontinued in K-mount.)

[stormtech]

I was thinking about it, and despite its larger-than-normal size, this new 18-35mm has the potential to lighten my load and simplify the process of deciding which lenses to carry with me. Here's why.

Whenever possible, I like to go with my small camera bag, which means one lens on my camera and one other in the bag. In the past I've frequently found myself unable to decide between my 10-20mm and 30mm 1.4 to accompany my longer 85mm 1.4 or 50-150mm 2.8, and wishing I could take both my wide angle and my fast standard to accompany my telephoto. When I can't make up my mind, or think I might need both, then I end up taking a larger bag and more lenses, which means more weight and more lens swaps.

Now, I'm thinking that in a lot of cases this 18-35mm 1.8 can take the place of both my 10-20mm and my 30mm 1.4, as long as I don't need an extreme wide angle. So I could see myself frequently going with the 18-35mm 1.8, along with either the 85mm 1.4 or the 50-150mm 2.8 depending on what I'm doing. So with just two lenses I've got a wide angle, a fast standard, and a fast telephoto.

In fact, I might go ahead and sell my 10-20mm to help finance the 18-35mm, since I've been wanting to get an 8-16mm eventually anyway. And the 8-16mm will also pair better with the 18-35mm. At least until Sigma comes out with a 10-18mm f2.8 lens.

It also occurs to me that the 18-35mm 1.8 also has the potential to replace my 30mm 1.4, but I'll probably hold onto it since I like it so much, it's not very expensive, and sometimes I like to go with just the 30mm since it's small and light.

This all sounds so familiar - our own justification process. That's a good thing!

[LFLee]

I am about to make the pre-order, but it appear it will only ship in August - and that passed my summer vacation date which I plan to use the lens extensively. So I might as well can wait. My question are:
1. how well did Sigma lens holds their values and how often they will have "sale" or rebate on their lens?
2. I read somewhere that people say Sigma lens "street price" is 30% off their MSRP. Is this true?

[stormtech]

2. I read somewhere that people say Sigma lens "street price" is 30% off their MSRP. Is this true?

The MSRP on this lens is $1160 so your 30% theory is just about right on.

SIGMA 18-35mm F1.8 DC HSM | Art Lens | sigmaphoto.com

[LFLee]

The MSRP on this lens is $1160 so your 30% theory is just about right on.

SIGMA 18-35mm F1.8 DC HSM | Art Lens | sigmaphoto.com

that's where it come from then...

[ryan s]

811 grams! I'm all for fast aperture lenses and I love using them. So I'm excited about a constant f/1.8 aperture, but then I look at my other lenses...a normal "loadout" would be the 12-24, FA 31, and DA* 55. Without doing the exact math, those three should be about 1000 grams, and you get 12mm at the wide end (though only f/4) plus 55mm at the long.

And since the Sigma is a zoom, where are the optical compromises made?

It looks like it's physically a bit bigger than the DA 17-70 so that's not too bad.

Hmm...it's such a good price and should be fun to use, but where does it fit...

[ElJamoquio]

811 grams!

That sounds about right... Sigma's 24-70 F/2.8 weighs only a hair less (20g) but is 16% wider and 31% longer, it all works out about right.

[Cannikin]

Considering it took the Sigma 35mm some 6 months from Canon's release to Pentax's, I find it highly doubtful it will be released anywhere close to B&H's July estimate.

[jay_akita]

I am about to make the pre-order, but it appear it will only ship in August - and that passed my summer vacation date which I plan to use the lens extensively. So I might as well can wait. My question are:
1. how well did Sigma lens holds their values and how often they will have "sale" or rebate on their lens?
2. I read somewhere that people say Sigma lens "street price" is 30% off their MSRP. Is this true?

More importantly than how well Sigma's hold value is that their pricing strategy remains sane - release a lens with great performance for a fair price and then maintain that price for the shelf life of that particular model! ie) if you buy a Sigma lens you don't have to worry about the price being randomly chopped in half a week after buying it. I bought the excellent 60mm macro 3 or 4 years ago and you can still get it new for the same price - it's a concept other *cough cough* brands could learn from

Great build quality and performance as well - Sigma has really been hitting some lenses out of the park lately and I'm thrilled to see the OEMs get some competition!

[Edgar_in_Indy]

I bought the excellent 60mm macro 3 or 4 years ago and you can still get it new for the same price - it's a concept other *cough cough* brands could learn from

Great build quality and performance as well - Sigma has really been hitting some lenses out of the park lately and I'm thrilled to see the OEMs get some competition!

I think that other lens makers could also learn something from Sigma's willingness to stand behind their lenses for 3 - 4 years, instead of just 1 year, and to provide quick service when your lens does need work.

[dankoBanana]

no doubt this thing is BIG. I'm not sure is it really for me, but i plan on getting one to find out. I've never had a fast (er than f2) lens and this lens excites me because it a 18-35 mm bag of f1.8 primes. It seems like my ideal walkaround lens for tourist trips.

[kerrad]

Today Polish site optyczne published detailed review of the lens. It seems that the lens gives great images indeed! You can check it here: Test Sigma A 18-35 mm f/1.8 DC HSM - Rozdzielczo (the site is in Polish so you can use Google translator).