[Aristophanes]

The guy with the D800 who was with me on this trip, really liked this shot....

1. Nice shot
2. Coud have gotten something similar to that effect with a the DA 15, again, compromises
3. Do you need an f/1.8 any lens for a shot like that?
4. The Pentax DA 10-17 FE can do similar (320g)

You have the wrong lenses on your list:

Sigma 20/1.8 (520 g)
Pentax 31/1.8 (345g)

No, I don't.

Comparing marginal aperture size increases on a large, short FL zoom to pancake primes is silly to begin with.

Starting with the beginning metric of aperture is like fudging the start line or moving the goalposts. Same for starting the baseline at size and mass. It's a very heavy, very short FL (less than 2x) zoom with bad flare. It is not a "stack of primes".

People here forget in the whole "replacement theory" abounding that all manufactures (except Leica) wants you to buy BOTH primes AND zooms for a complete shooting experience. That's why the DA Limited primes are designed as pancakes. They are that way precisely to avoid the compromises something like the Sigma represents.

[momotazur]

Pentax users who don't comprehend the weight thing. Do you guys all shoot in studios? Do you guys honestly think you're going to walk around with a 2 pound lens around your neck? I do it sometimes, but it hurts. And as a general rule, I devise strategies to avoid pain.

I absolutely agree. After carrying around the sigma 35 f1.4 for few days, I felt SO HAPPY to take the DA 16-45 with me.

[Andi Lo]

No, I don't.

Comparing marginal aperture size increases on a large, short FL zoom to pancake primes is silly to begin with.

Starting with the beginning metric of aperture is like fudging the start line or moving the goalposts. Same for starting the baseline at size and mass. It's a very heavy, very short FL (less than 2x) zoom with bad flare. It is not a "stack of primes".

People here forget in the whole "replacement theory" abounding that all manufactures (except Leica) wants you to buy BOTH primes AND zooms for a complete shooting experience. That's why the DA Limited primes are designed as pancakes. They are that way precisely to avoid the compromises something like the Sigma represents.

Everything in context.

When your subject is not static, you're at the top limit for acceptable ISO of your camera, you're at f/4, and the shutter reads 1/30, this lens will get the shot, and the pancake wont.

If you use flash, you can increase the strength of ambient light by at least 1 stop by using this lens vs using pancake primes.

I dont think it's the comparison is baseless, this lens truly can do what alot of wide FL primes can't at an acceptable cost and size.

On the other hand when you're out shooting for fun and you have the option between a K-5/18-35 and K-5 /DA 15 + K-x/DA 40, I personally would opt for the latter. If I only have the 18-35 in my stable, I often would probably just bring my phone cam. In this context the prime will get the shot, and the zoom won't.

Like you said manufacturers would like us to have both, and it makes alot of sense to do so. However from a performance point of view this lens truly performs like a stack of primes, as the aperture can open to 1.8 when necessary, and still have very decent performance.

Like in normhead's shot above, the DA 15 could get the shot, but the Sigma 8-16 is a better deal with better specs at a marginal cost of size. You can also argue that he may not have gotten the shot if he had to pano the DA 15. Not dissing the DA 15 though as I think it's a truly amazing lens design, and the DA 15 club is imho the most impressive club in this forum. I fully agree with you that there's something special about shooting with a fixed FL small prime, it's not the same experience.

[normhead]

1. Nice shot
2. Coud have gotten something similar to that effect with a the DA 15, again, compromises
3. Do you need an f/1.8 any lens for a shot like that?
4. The Pentax DA 10-17 FE can do similar (320g)

1. Thanks
2. This one was shot at 8mm, I looked at the 15 before I bought the 8-16, it's not as corrected and has more barrel distortion and CA. The 8-16 is a truly amazing lens.
3. No, but that's part of my problem with the 18-35, is who needs f 1.8 in a wide angle? Some do I guess.
4 I own the 10-17 and have shot with it from this exact camera position on other trips. I've shot some locations where the 10-17 was preferable, but the perspective in this location was unsuitable for the 10-17's distortion. In my experience, you almost need to carry both of these lenses. Some may not realize it but an image corrected for barrel distortion, creates a different type of distortion, parts of the image, especially at the edges get compressed and flattened. Straight lines are created at the expense of accuracy in terms of scale and proportion.

[Barry Pearson]

The guy with the D800 who was with me on this trip, really liked this shot....


But he didn't get it for himself... he decided his 14-24 was too heavy to carry that night. Oh well, he can always look at mine on photo bucket, taken with my half it's weight Sigma 8-16. I have trouble understanding Pentax users who don't comprehend the weight thing. Do you guys all shoot in studios? Do you guys honestly think you're going to walk around with a 2 pound lens around your neck? I do it sometimes, but it hurts. And as a general rule, I devise strategies to avoid pain.

For the last 4 years I've often spent all day using my DA* 60-250mm f/4 on a K-7 then K-5 then K-5IIs, (with battery grip). for motor sports, airshows, urban candids, etc. (Sometimes I use my DA* 300mm f/4 instead). Sometimes in addition I carry my DA 12-24mm f/4 and perhaps one or two other Pentax zooms too, such as my DA 17-70mm f/4 and/or DA10-17mm Fisheye, perhaps for landscapes.

Obviously I don't carry them round my neck! I often use a photo-vest to spread the weight when walking around. When shooting I wrap the strap round my right wrist, or simply not bother to use the strap. (I remove the strap in my studio).

If I want a light-weight carry-anywhere combination, I use my Q system instead. No lens on a K-5IIs is going to make it a carry-anywhere camera (for me).

[normhead]

For the last 4 years I've often spent all day using my DA* 60-250mm f/4 on a K-7 then K-5 then K-5IIs, (with battery grip). for motor sports, airshows, urban candids, etc. (Sometimes I use my DA* 300mm f/4 instead). Sometimes in addition I carry my DA 12-24mm f/4 and perhaps one or two other Pentax zooms too, such as my DA 17-70mm f/4 and/or DA10-17mm Fisheye, perhaps for landscapes.

Obviously I don't carry them round my neck! I often use a photo-vest to spread the weight when walking around. When shooting I wrap the strap round my right wrist, or simply not bother to use the strap. (I remove the strap in my studio).

If I want a light-weight carry-anywhere combination, I use my Q system instead. No lens on a K-5IIs is going to make it a carry-anywhere camera (for me).

I, on the other hand carried my kit, Sigma 70 macro, 18-135, 60-250 and A-400 for 11 kms the other day... I probably wouldn't carry that much for 15 kms though
In rough terrain, I won't use anything where the camera isn't protected in a padded case. That means, a belt with shoulder support and Lowenpro bags for everything. I've fallen enough times with exposed gear to know how much it can hurt, when the hand you should have caught yourself on had a camera in it, or had to protect a camera from hitting the ground. I'd love to be able to carry a Q, for me the IQ isn't there yet.

[Winder]

I have been carrying a Contax 645 with me since they were still in production. Hiking, Kayaking, 5 day backpacking trips. I get a good chuckle out of some of the size and weight comments. I'm going to take the best tool I have for the job and the size has never really been an issue. The thought of spending 2 days to pack into a location only to have less than my best equipment seems like a huge waste of time.

For the enthusiast who just want to have a "just in case" camera and lens with them, I can see size and weight being really important. IF you are going with a purpose though, the size and weight is a secondary consideration.

[Barry Pearson]

I, on the other hand carried my kit, Sigma 70 macro, 18-135, 60-250 and A-400 for 11 kms the other day... I probably wouldn't carry that much for 15 kms though
In rough terrain, I won't use anything where the camera isn't protected in a padded case. That means, a belt with shoulder support and Lowenpro bags for everything. I've fallen enough times with exposed gear to know how much it can hurt, when the hand you should have caught yourself on had a camera in it, or had to protect a camera from hitting the ground. I'd love to be able to carry a Q, for me the IQ isn't there yet.

I typically use a photo-vest for long walks. The two pockets at the bottom are big enough for a DA* 60-250mm f/4 or a DA* 300mm f/4, or a Fish-eye plus another zoom in one pocket. I certainly don't carry exposed cameras in my hands while walking any distance or on rough ground.

My Q7 only arrived this morning. From a quick test it certainly has better image quality than the Q, but I don't yet know how much better. (And obviously I can't say whether it would satisfy anyone else). I intend to try an A3+ print from it just to see what I get.

[normhead]

I have been carrying a Contax 645 with me since they were still in production. Hiking, Kayaking, 5 day backpacking trips. I get a good chuckle out of some of the size and weight comments. I'm going to take the best tool I have for the job and the size has never really been an issue. The thought of spending 2 days to pack into a location only to have less than my best equipment seems like a huge waste of time.

Yes and Ansel Adams carried an 8x10 tilt shift on a pack mule... as one who has carried a 645 on those types of trips, I'd say, if I can ever afford a 645D I'll probably do it again. Not on a hike, but on a canoe trip. For just in case, I also carry an Optio W10. Just in case can happen anytime, no matter what you have in your camera bag.

[Andi Lo]

Obviously I don't carry them round my neck! I often use a photo-vest to spread the weight when walking around. When shooting I wrap the strap round my right wrist, or simply not bother to use the strap. (I remove the strap in my studio).

If I want a light-weight carry-anywhere combination, I use my Q system instead. No lens on a K-5IIs is going to make it a carry-anywhere camera (for me).

I want to chime in on the weight issue of big lenses. When you need to carry heavy lenses, consider investing in something like the cotton carrier, Blackrapids or similar. It really allows you to carry heavier gear with ease. Cotton carrier is why I always say that for paid work, gear weight for the most part does not matter. They got a promotion video of a guy doing parkour with a Canon 5d + 16-35 on his cotton carrier vest. Having used one I'm confident that the video is no trickery

I find that limiteds and small lenses work great with blackrapids on K10 + grip. I use the cotton carrier on my belt for the heavier zoom lenses, and use the vest only when necessary

I should post a review at some point for both of these accessories...

[Aristophanes]

When your subject is not static, you're at the top limit for acceptable ISO of your camera, you're at f/4, and the shutter reads 1/30, this lens will get the shot, and the pancake wont.

With ridiculously shallow DOF. Boof! Out the door go photographic aesthetics. And certainly any variety within. This is the uber-compromise of the quest for fast glass: it all starts to look the same. And softer.

The quest for fast glass to "get the shot" is also, therefore, a set of compromises. You'e getting part of "the shot" because you now have more OOF. That seems to be forgotten. And it looks contrived, same-same, or just poor technique when repeated over and over. It turns every shot into a bokeh thread, never mind the ear is OOF, the nose is OOF, but they eyes are in focus. Fast glass used simply because it is fast ignores the reality that aperture has more to do with DOF than more photons.

[Andi Lo]

With ridiculously shallow DOF. Boof! Out the door go photographic aesthetics. And certainly any variety within. This is the uber-compromise of the quest for fast glass: it all starts to look the same. And softer.

The quest for fast glass to "get the shot" is also, therefore, a set of compromises. You'e getting part of "the shot" because you now have more OOF. That seems to be forgotten. And it looks contrived, same-same, or just poor technique when repeated over and over. It turns every shot into a bokeh thread, never mind the ear is OOF, the nose is OOF, but they eyes are in focus. Fast glass used simply because it is fast ignores the reality that aperture has more to do with DOF than more photons.

At 18mm even at f/1.8 DOF should be pretty decent (20mm when focused at 1m according to the calculator - yes I know it's sometimes inaccurate). That should be enough to cover nose and eyes.

I've used the FA 35/2 extensively at f/2 at those exact conditions I mentioned and my clients are happy with the images. Sometimes I'm even forced to manual focus it since it's so dark, and the results are acceptable for my uses. Again this is a situation where getting the shot matters while photographic perfection doesnt. I honestly never look at the ears when shooting people. I never had a non-keeper because the ears are not sharp. I have had way more non-keeper from bad bokeh / bad bokeh composition / too dark ambient lighting than ear sharpness (fully my fault, of course)

I would gladly switch my FA 35 to this lens if it means I gain 18mm/1.8 on the same lens - for paid work, not for fun. In fact I often feel limited by the sigma 10-20 exactly because it doesnt open up enough for ambient lighting when using flash. The lens having 1.8 through the whole range is a fact. Whether it's useful to you or not, that's another matter. It can functionally replace two lenses that have a place in many people's bag, a fast 20mm and a fast 35mm

i really should stop arguing about a lens I dont even own. Maybe I will continue if I buy this lens at some point

[Aristophanes]

At 18mm even at f/1.8 DOF should be pretty decent (20mm when focused at 1m according to the calculator - yes I know it's sometimes inaccurate). That should be enough to cover nose and eyes.

18mm at 1m on a portrait is a distortion FL. Rare is the portrait that close. That's why I find this lens odd and the excitement odder. It's a spec seller, not a function seller. People who equate fast glass as better ignore the real world application of OOF compromises.

It's like they assume faster glass will "get the shot" when they just lost the shot because of OOF!

Then they complain about sharpness and buy another lens.

[Andi Lo]

18mm at 1m on a portrait is a distortion FL. Rare is the portrait that close. That's why I find this lens odd and the excitement odder. It's a spec seller, not a function seller. People who equate fast glass as better ignore the real world application of OOF compromises.

It's like they assume faster glass will "get the shot" when they just lost the shot because of OOF!

Then they complain about sharpness and buy another lens.

The argument is even stronger when focus length is longer, you get more DOF as you approach hyperfocal distance, so the OOF point is moot. I just used 1m as an approximate as the closest you'd want for (distorted) portrait, so most likely you'd get OOF at that focus distance.

FYI At 18mm I'd probably crop the photo to 16:9 ratio, or shoot from overhead, where the focus distance would be really close to hyperfocal.

But yes I agree that sometimes people get OOF due to poor technique and blame the glass for not being fast enough. My argument here is for shooting moving subject and maximizing ambient light, as I have often felt that even f2.8 does not give me enough photons for a reasonable shutter speed (ie 1/60; I often do 1/40 but it's a gamble)

[Mock]

Ah...yes. The ancient argument of primes vs. zooms.

Especially the "bulky" part (it's an SUV of a lens with a very short FL range).

DA 21/3.2 = 140g
DA 35/2.4 = 124g

Sigma = 810g

Oh, heck! ...let's throw a few more primes in just for the sake of it:

DA 40/2.8 = 90g
DA 15/4.0 = 212g
DA 70/2.4 = 130g

Nope...still not there. And one could do without either the 35 or 40.

So for a slight bit of speed and lot more flare, this "stack of primes" isn't really a stack of primes. Different philosophies of design, functional use, and market. There are always trade-offs. This Sigma is no different.

I heard this argument when shooting the Nikon 14-24 (1000g). After awhile, other arguments sound better as the marks on the shoulder accumulate.

I mentioned saving space, not weight, in my bag. A few hundred grams one way or the other does not bother me.
The 4 lenses I mentioned come out to 23cm stacked one on top of the other, with the DA 40 XS neatly hidden away within the extended lens hood of the 18-55. The total weight is 716 grams, compared to 810g and ~17cm length of the Sigma with the hood in shooting position. With this lens on my camera, there is also less weight in the bag from lenses not currently mounted, so my shoulder will actually be better off too!

So, I must carry the heavy burden of 94 extra grams, but in return I can shoot any focal length from 18-35mm at f/1.8 with at least equal image quality. Even if you have a strong artistic distaste for shallow DOF (again, to each their own), you are also working with much more light. This is the kind of light I like to shoot in, handheld. This is at 1/80s, f/2, ISO 2500, centre-weighted metering, with the DA* 55.
Let's say I get closer to this train for a wide angle shot with the 18-35. It would probably be something like 18mm, f/2, 1/40s, ISO 1250. On a warmer night I could probably get the shutter down to 1/10s with VR, granting me a nice low ISO of 320. Same conditions with the DA 21 gets me ISO 3200 and 800, respectively.

The example assumes I don't care about the aesthetic qualities of shooting f/2 or f/3.2. With the locomotive say 5m away, 18mm f/2 gives me a DOF of 9.9m, while 21mm f/3.2 nets me 18m of acceptable focus. If I don't have those extra 8 metres of focus towards the back of the locomotive, does it matter? I'd rather have a file at ISO 320 than 800, so I would say it does not matter. This is yet another matter of personal opinion, of course.
Personally, I prefer to have as many options as I can, which is why I don't mind having 18mm at f/1.8, especially when there is no penalty in IQ.