Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
06-15-2013, 02:21 AM   #76
Veteran Member
dankoBanana's Avatar

Join Date: Dec 2008
Location: Zagreb, Croatia
Posts: 535
QuoteOriginally posted by bossa Quote
I agree.. my 70-200 F2.8 VRII is already too much to handle for me with my current back issues. My D800e with grip (with extra battery) weighs 3kg with that lens attached. My DA*50-135 was in Japan for 4 months being repaired and that drove me over the top and I sold just about all of my Pentax gear last year.
Ive settled with a cheap and slower alternative. Sigma AF 75-200 f3.8 . I got it for 70 euros, and its FF compatible. It suits my k5 well in terms of size and weight. Its not TOPoptics but its very good

And BOOM, ive steered the conversation back to Sigma ))

06-15-2013, 03:13 AM   #77
Pentaxian
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,862
QuoteOriginally posted by Edgar_in_Indy Quote
It's just shocking to me that the first affordable consumer zoom lens with an aperture faster than f/2.8 is not an m43 lens, but is instead an APS-C lens
That's not true exactly.

First, these constant aperture zooms are all pro zooms, not consumer zooms.

Then, Olympus has the 14-35/2 lens at 2300 USD which is 35mm-equivalent to 28-70/4.

So, the above was the first faster than F2.8 zoom and it indeed was for the FT system.

But the Sigma now is 35mm-equivalent to 28-50/2.8 which is the first example of a 35mm-equivalent F2.8 zoom for a smaller sensor.

Impossible to make for FT as it would require an F1.4 aperture zoom with the FT sensor.

And normally because the optical problems to make fast zooms increase with F-stop in parallel to lens diameter, the smaller sensor zooms would be more expensive as the Olympus example demonstrates.

The real impact of the Sigma lens is that it is priced just as affordable as its 35mm-equivalent full frame peer (the Sigma one). Absolutely technically impossible to do for the FT system. Even for APSC, I have the impression that we see some good aggressivity from Sigma here to meet the full frame price point.

QuoteOriginally posted by rawr Quote
I laughed hard at the irony when I read some comments from full-frame users on another site that his lens may tempt them back to APS-C
I already made a similiar comment higher up in this thread. That this lens breaths new air in the APSC system.

Nonetheless, a combo like D800E+24-70/2.8G delivers an image resolution, zoom range and focus accuracy which is still unmatched. Where it is matched now is wrt low light capability and shallow DoF. Which is good enough in many cases.
06-15-2013, 06:07 AM   #78
Pentaxian
Edgar_in_Indy's Avatar

Join Date: May 2010
Location: Indiana, USA
Photos: Gallery
Posts: 2,555
QuoteOriginally posted by falconeye Quote
That's not true exactly....Olympus has the 14-35/2 lens at 2300 USD which is 35mm-equivalent to 28-70/4.
If you go back and read my post, you'll see that I specifically referenced the "crazy-expensive 4/3 lenses", and that the Sigma 18-35mm is the first affordable zoom faster than f/2.8.

I suppose it's debatable whether it's a "consumer" or "professional" lens, but it would probably be a rather pointless debate. You're probably right that it could be considered professional based on what we know about its technical specs and build quality so far. But its price is closer to consumer level. If it's being introduced at $799, then I imagine that eventually the price will go lower, assuming they are able to manufacture it in sufficient quantities.

The pricing on those f2 Olympus zooms has always been a head-scratcher for me. What kind of photographer spends $2300 for a lens to use on a 4/3 DSLR? In other words, what 4/3 DSLR these days is worthy of a $2300 lens?
06-15-2013, 08:06 AM   #79
Forum Member




Join Date: Feb 2012
Location: Bridgewater, New Jersey
Photos: Albums
Posts: 61
I currently have the older Sigma 28mm F1.8 prime and this is what it could deliver. Both shot at F1.8 (actually shows up as 1.7 on K5). 1/30 shutter on 1st and 1/50 on 2nd. No PP. I find pictures sharper by dialing extra shutter speed and negative compensation of -.7. This lens could be had now used for less than 300 on EBAY. It is chunky (77mm). This upcoming Sigma zoom is even heavier and longer.

So my problem is if I will have much more use for the F1.8 at the extreme ends, 18 and 35. I can't really see gaining much on the wide end if its a landscape type of shot where you will have to stop down and if its for isolating the subject, may have to get closer than what I do now with 28mm to get the thin DOF, which then shrinks you angle anyway. The 35 mm may be more useful for people shots with less perspective distortion and still retaining the thin DOF. But how much difference will it be against the DA 35 2.4.

My wish list with Sigma is for them to update their wide primes (20, 24, 28) to get them smaller and lighter. Instead of this new zoom, I think my ideal one will be a new 24mm prime F1.8 that is the size of the DA 18-55 and about 400 gm.

Attached Images
View Picture EXIF
PENTAX K-5 II  Photo 
View Picture EXIF
PENTAX K-5 II  Photo 
06-15-2013, 11:57 AM   #80
Loyal Site Supporter




Join Date: Apr 2010
Location: Tennessee
Posts: 5,420
QuoteOriginally posted by Edgar_in_Indy Quote
I
The pricing on those f2 Olympus zooms has always been a head-scratcher for me. What kind of photographer spends $2300 for a lens to use on a 4/3 DSLR? In other words, what 4/3 DSLR these days is worthy of a $2300 lens?
I had both with my E-3. Nobody was making pro-grade professional sub-FF cameras at the time. The build quality is amazingly good. I bought them for kayaking and backpacking. My Contax 645 was even bigger and heavier and had no weather sealing. I wanted the reach of 4/3 sensor. The 300mm F.2,8 ZD for 4/3 was around $6,000 back then and the equivalent FF 600mm lens was $10,000 and huge.

I did a full roll in my kayak with the E-3 and 35-100 around my neck and it never missed a beat. If Olympus had been making professional grade prime lenses like the 12mm, 45mm, 75mm that they make for M4/3 I would still be using Olympus 4/3.
06-15-2013, 12:50 PM   #81
Pentaxian
Edgar_in_Indy's Avatar

Join Date: May 2010
Location: Indiana, USA
Photos: Gallery
Posts: 2,555
QuoteOriginally posted by Winder Quote
I had both with my E-3. Nobody was making pro-grade professional sub-FF cameras at the time....If Olympus had been making professional grade prime lenses like the 12mm, 45mm, 75mm that they make for M4/3 I would still be using Olympus 4/3.
That's cool that you actually owned one of those lenses. From everything I've heard, they're pretty amazing.

My first two DSLR's were Olympus...e-410 and e-520. I really liked them, but they were just getting left farther and farther behind in image quality compared to the APS-C cameras, especially at ISO 800 and above. Hopefully Olympus will come out with a successor to the E-5 with a newer image sensor, but until then I couldn't imagine spending $2300 on a 4/3 lens.

I'm actually kind of surprised Sigma hasn't been more aggressive in coming out with m43 lenses since there seems to be a lot of money flowing into that system these days, but I suppose they've probably been busy with other things...like designing the 18-35mm.

Last edited by Edgar_in_Indy; 06-15-2013 at 01:25 PM.
06-15-2013, 02:42 PM   #82
Site Supporter




Join Date: Feb 2011
Posts: 4,892
Very impressive. I had expected it to be more expensive than the 24-70 F/2.8 but it turns out it's the same price... maybe. Sigma's have a history of deep discounts, don't think that would apply to this lens though.
06-15-2013, 03:13 PM   #83
Pentaxian
Edgar_in_Indy's Avatar

Join Date: May 2010
Location: Indiana, USA
Photos: Gallery
Posts: 2,555
QuoteOriginally posted by ElJamoquio Quote
Sigma's have a history of deep discounts, don't think that would apply to this lens though.
I expect you're right. The reviewers I was reading were saying that you'll be lucky to get your hands on one at all anytime soon due to the anticpated demand. Kind of surprises me that they're already releasing in Pentax/Sony mount since they could probably sell their full production capacity to Canon/Nikon.

06-15-2013, 05:15 PM   #84
Pentaxian
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,862
QuoteOriginally posted by Edgar_in_Indy Quote
If you go back and read my post, you'll see that I specifically referenced the "crazy-expensive 4/3 lenses", and that the Sigma 18-35mm is the first affordable zoom faster than f/2.8.
I got it the first time. But what is affordable for you may not be affordable for others. The Olympus F/2 zooms have been affordable for some. It is a world where lenses can cost 5000$ or 10000$...

I know this discussion from the pricing of Nikon's new 80-400G zoom. Many say crazy pricing. Many say affordable compared to any alternative at 400mm and above.

If you meant sub $1000 lenses, then yes.

However, I have the impression that the 18-35/1.8 is a lens which is expensive to make. I wouldn't be surprised to see its price go anything but up. Its launch price seems to be a bold statement.

What I wanted to highlight in my previous posts ... To do an F2.8 equivalent zoom for sensors smaller than full frame is technically difficult. Much for APSC and almost impossibly difficult for FourThird. The Olympus zooms don't have a crazy pricing if you consider the technical achievement.

You can always ask for the dream lens *you* can still afford. But it won't make physics disappear
06-15-2013, 06:14 PM   #85
Pentaxian
Edgar_in_Indy's Avatar

Join Date: May 2010
Location: Indiana, USA
Photos: Gallery
Posts: 2,555
QuoteOriginally posted by falconeye Quote
I got it the first time. But what is affordable for you may not be affordable for others. The Olympus F/2 zooms have been affordable for some. It is a world where lenses can cost 5000$ or 10000$...
I think that most people know what an "affordable" anything generally refers to, without over-thinking it. Kind of like how a new BMW M5 won't usually be labeled as an affordable car, despite the fact that there are a lot of people who can easily afford it. And like how a K-01 might be called an affordable APS-C camera, even though it costs more than what the average person in some third-world countries probably make in the better part of a year. I expect that most people who frequent this forum and and who are participating in this thread in particular would have a similar reference of what an expensive lens is.

In my mind (for whatever that's worth), whether a product is "affordable" has something to do with the price of the item in question in comparison to the average price, and extreme high/low prices, of items in the same broadly general category. If that makes any sense!

QuoteOriginally posted by falconeye Quote
To do an F2.8 equivalent zoom for sensors smaller than full frame is technically difficult. Much for APSC and almost impossibly difficult for FourThird. The Olympus zooms don't have a crazy pricing if you consider the technical achievement.
I'm pretty sure you know a lot more about lenses than me, but so far we have an "affordable" (ha ha) APS-C lens zoom lens that is constant f1.8, and then you have the Panasonic Lumix LX-7 which has a sensor smaller than 4/3 and they were able to put an f1.4-f2.3 zoom lens on that without breaking the bank. So it seems strange to me that the 4/3 sensor, which is between the two above-mentioned sensors in size, could not do similar at a "reasonable" (ha ha) price.

Last edited by Edgar_in_Indy; 06-15-2013 at 06:28 PM.
06-15-2013, 06:25 PM   #86
Pentaxian
Pål Jensen's Avatar

Join Date: Dec 2007
Location: Norway
Photos: Albums
Posts: 3,064
QuoteOriginally posted by falconeye Quote
What I wanted to highlight in my previous posts ... To do an F2.8 equivalent zoom for sensors smaller than full frame is technically difficult. Much for APSC and almost impossibly difficult for FourThird. The Olympus zooms don't have a crazy pricing if you consider the technical achievement.

You can always ask for the dream lens *you* can still afford. But it won't make physics disappear
You mean DOF (wide open) equivalent lenses (such lenses won't give the same image cross formats). However, for exposure equivalent lenses (F: 1.8 is F:1.8 regardless of format) a similar lens is very hard to do for FF and it will be significantly more expensive (these lenses won't either make identical images cross formats). Only simlar focal lenghts and same numerical aperture are truly equivalent cross formats. (They won't give the same image unless you crop but the lenses are equivalent).
As for physics; an image IS an exposure and images will never be identical cross formats.

Last edited by Pål Jensen; 06-15-2013 at 06:57 PM.
06-15-2013, 06:32 PM   #87
Site Supporter




Join Date: Feb 2011
Posts: 4,892
QuoteOriginally posted by Pål Jensen Quote
You mean DOF (wide open) equivalent lenses (such lenses won't give the same image cross formats). However, for exposure equivalent lenses (F: 1.8 is F:1.8 regardless of format) a similar lens is very hard to do for FF and it will be significantly more expensive (these lenses won't either make identical images cross formats). Only simlar focal lenghts and same numerical aperture are truly equivalent cross formats. (They won't give the same image but the lenses are equivalent).
As for physics; an image IS an exposure and images will never be identical cross formats.
Physics is physics, and falconeye is correct.
06-15-2013, 06:38 PM   #88
Pentaxian
Pål Jensen's Avatar

Join Date: Dec 2007
Location: Norway
Photos: Albums
Posts: 3,064
QuoteOriginally posted by ElJamoquio Quote
Physics is physics, and falconeye is correct.
Physics is physics but whats interesting is the physics of exposure, not the physics of DOF measuring devices where the final image forming process and its resuts is kept out from the question; not to mention the whys, if's and buts to goes into the creative image forming process.
A DOF equivalent lens is no more equivalent than a exposure equivalent lens. Neither is equivalent but they are equally so. It is a purely subjective decision what is important for you but most photographers is in the latter category. Thats why lens manufacturers doesn't even state the thinnes of DOF wide open in their specs, while aperture and maximum magnification is.

As for formats; it is important to keep the whys of different formats reasonably constant. I mean, no one buy an FF camera in order for it to be equal to an APS one. You'll like to maintain its advantages at every oportunity you can.

Last edited by Pål Jensen; 06-15-2013 at 07:02 PM.
06-15-2013, 06:56 PM - 2 Likes   #89
Pentaxian
Edgar_in_Indy's Avatar

Join Date: May 2010
Location: Indiana, USA
Photos: Gallery
Posts: 2,555
QuoteOriginally posted by ElJamoquio Quote
Physics is physics, and falconeye is correct.
Well, in a way. But I think his analysis presupposes that it is necessary or desirable for an m43 lens to achieve the same shallow depth of field as the FF equivalent. I was initially a little confused by his comments until I realized he was speaking to both exposure and depth of field. But some people may actually consider the increased depth of field of M43 at equivant apertures to be an advantage compared to FF.

There are times when you want the fast shutter speed that a large aperture allows, but you may not want the extremely thin DOF that you would get at the same given aperture on FF. For example, you want the entire ballerina to be in focus, and to be free of motion blur. It really just depends on your photography. So since the differences in DOF is not an objective positive or negative, I think it's best to just leave it out of the discussion for the most part, except as an informational footnote.

Last edited by Edgar_in_Indy; 06-15-2013 at 07:11 PM.
06-15-2013, 07:00 PM   #90
Pentaxian
Pål Jensen's Avatar

Join Date: Dec 2007
Location: Norway
Photos: Albums
Posts: 3,064
QuoteOriginally posted by Edgar_in_Indy Quote
Well, in a way. But I think his analysis presupposes that it is necessary or desirable for an m43 lens to achieve the same shallow depth of field as the FF equivalent. But some people may actually consider the increased depth of field of M43 at equivant apertures to be an advantage compared to FF.

There are times when you want the fast shutter speed that a large aperture allows, but you may not want the extremely thin DOF that you would get at the same given aperture on FF. It really just depends on your photography. So since the differences in DOF is not an objective positive or negative, I think it's best to just leave it out of the discussion for the most part, except as an informational footnote.


I wish I could put it as well myself!
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
18-35mm, angles, aperture, cameras, canikon, canon, dc, f/2.8, f1.8, fisheye, hsm, iso, k-3, landscape, length, lens, lenses, motor, mounts, nikon, pentax, pentax news, pentax rumors, review, sigma, sigma 18-35mm f1.8, sr, uk, zeiss
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sigma 35mm F1.4 for Pentax: ETA 4/30 Adam Pentax News and Rumors 181 02-16-2014 06:44 PM
Sigma 18-35mm f/1.8 detail. rlatjsrud Photographic Industry and Professionals 42 10-06-2013 01:41 PM
New Sigma 18-35 F1.8 APS-C yygomez Pentax SLR Lens Discussion 10 04-19-2013 04:11 PM
Pentax 35mm F2.4 AL DA L Lens vs Sigma 28mm f1.8 Aspherical orchid Pentax SLR Lens Discussion 8 04-22-2011 12:44 AM



All times are GMT -7. The time now is 11:45 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top