Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version 2 Likes Search this Thread
10-26-2010, 08:35 PM   #16
Inactive Account




Join Date: Jul 2010
Location: Chicago
Photos: Gallery
Posts: 672
QuoteOriginally posted by Kirivon Quote
Saying it has soft edges is different from saying that it has low resolution or lacks contrast, though. Going off center resolution, the Sigma beats nearly every prime in the current lineup. It is also probably the most punchy lens I own in terms of contrast and color rendition, especially wide open.

The corner resolution isn't stellar but the nature of the lens makes it a non-factor. LoCAs are really well controlled and, outside of sharpness, the lens doesn't gain anything past f/1.4. Basically the Sigma is a lens you buy for the f/1.4, use at f/1.4, and love at f/1.4.

QuoteQuote:
The borders improve to good levels by f/2 whereas the corner quality remains poor and it doesn't get much better at f/2.8. At f/4 the border/corner quality starts to lift a little but it takes f/8 till the extreme corners reach good levels. This is again in line to what we've seen in the corresponding test of the Canon variant.
I'll stay with what I stated. It's a good lens, but I'd like to be able to use my lens at more than just a couple stops, personally. Someday I may own one; however, it would have to be at the right price.

And beats every prime in the current line-up? Of whom? And what focal length? For Sigma, the 50mm beats the 30mm handedly. And if we're talking 30-40, there's plenty that will beat it. If it's about best bang for the buck, then this is a contender, but it's arguable.

10-26-2010, 09:05 PM   #17
Senior Member




Join Date: Sep 2009
Location: Okc
Photos: Gallery
Posts: 284
QuoteOriginally posted by RolloR Quote
Ooh wow there's such a thing as a Sigma 28mm f1.8 also for Pentax. And it seems cheaper than the 30/1.4. Anybody have that one also? 77mm filter thread though!
Got one of them....also
10-26-2010, 09:07 PM   #18
Senior Member




Join Date: Sep 2009
Location: Okc
Photos: Gallery
Posts: 284
and love it!!
10-26-2010, 09:10 PM   #19
Veteran Member




Join Date: Sep 2007
Location: La Crescenta, CA
Posts: 7,450
Some at f/1.4:







At f/2:



At f/2.8:



10-26-2010, 09:11 PM   #20
Veteran Member




Join Date: Sep 2007
Location: La Crescenta, CA
Posts: 7,450
Lately I've been thinking more and more seriously about ditching the FA31 to go back to the Sigma 30.
10-26-2010, 09:28 PM   #21
Inactive Account




Join Date: Jul 2010
Location: Chicago
Photos: Gallery
Posts: 672
QuoteOriginally posted by deadwolfbones Quote
Lately I've been thinking more and more seriously about ditching the FA31 to go back to the Sigma 30.
Well, that should say something right there. Says a lot more than my lab tests against it. If it holds up that well side-by-side, I'd say it's a great value.
10-26-2010, 10:00 PM   #22
Veteran Member
Smeggypants's Avatar

Join Date: Sep 2010
Posts: 1,536
QuoteOriginally posted by Rory Quote


I'll stay with what I stated. It's a good lens, but I'd like to be able to use my lens at more than just a couple stops, personally. Someday I may own one; however, it would have to be at the right price.

And beats every prime in the current line-up? Of whom? And what focal length? For Sigma, the 50mm beats the 30mm handedly. And if we're talking 30-40, there's plenty that will beat it. If it's about best bang for the buck, then this is a contender, but it's arguable.
The fact you have to post technical specs to argue against this lens means you're kinda missing the point.

Look at the example pics posted.

10-26-2010, 10:12 PM   #23
Veteran Member
gnaztee's Avatar

Join Date: Nov 2007
Location: West Palm Beach, FL
Posts: 772
On the 24 and 28

Not to hijack the thread, but since it came up, anybody want to throw on pics or personal impressions of the Sigmas 24 and 28mm 1.8? I'm in the market for a wider fast lens, as well as a little longer fast lens, and I'm really looking at the 24/28/30 from Sigma as options!
10-26-2010, 11:25 PM   #24
Senior Member




Join Date: Sep 2009
Location: Okc
Photos: Gallery
Posts: 284
^^^I'll see what I can scratch up^^^^
10-26-2010, 11:36 PM   #25
Senior Member




Join Date: Sep 2007
Location: Colorado
Posts: 173
QuoteOriginally posted by Rory Quote
And beats every prime in the current line-up? Of whom? And what focal length?
Well, let's revisit what I said.
QuoteOriginally posted by Kirivon Quote
Going off center resolution, the Sigma beats nearly every prime in the current lineup.
So...

Sigma 30mm f/1.4 peak center resolution: 2,453LW/PH @ F/4

Pentax 14mm f/2.8 peak center resolution: 2,178.5LW/PH @ F/8
Pentax 15mm f/4 peak center resolution: 2,352LW/PH @ F/5.6
Pentax 20mm f/2.8 peak center resolution: 2,195.5LW/PH @ F/5.6
Pentax 21mm f/3.2 peak center resolution: 2,290.5LW/PH @ F/5.6
Pentax 24mm f/2 peak center resolution: 2,327LW/PH @ F/5.6
Pentax 31mm f/1.8 peak center resolution: 2,345LW/PH @ F/4
Pentax 35mm f/2 peak center resolution: 2,336LW/PH @ F/4
Pentax 35mm f/2.8 peak center resolution: 2,256.5LW/PH @ F/5.6
Pentax 40mm f/2.8 peak center resolution: 2,274LW/PH @ F/5.6
Pentax 43mm f/1.9 peak center resolution: 2,422LW/PH @ F/4
Pentax 50mm f/1.4 peak center resolution: 2,320.5LW/PH @ F/4
Pentax 55mm f/1.4 peak center resolution: 2,318LW/PH @ F/4
Pentax 70mm f/2.4 peak center resolution: 2,238.5LW/PH @ F/5.6
Pentax 35mm f/2.8 peak center resolution: 2,256.5LW/PH @ F/5.6
Pentax 77mm f/1.8 peak center resolution: 2,326LW/PH @ F/4
Pentax 100mm f/2.8 peak center resolution: 2,109.5LW/PH @ F/8
Pentax 100mm f/2.8 peak center resolution: 2,194LW/PH @ F/5.6
Pentax 135mm f/2.5 peak center resolution: 2,130.5LW/PH @ F/5.6
Pentax 200mm f/2.8 peak center resolution: 2,074LW/PH @ F/5.6
Pentax 300mm f/4.5 peak center resolution: 2,082LW/PH @ F/5.6

As for the Sigma 30mm vs 50mm

30 @ f/1.4 = 1,880.5 LW/PH
50 @ f/1.4 = 1,779.5 LW/PH
even up at f/4 with 2,117 LW/PH

And on the pentax side of things
30 @ f/1.4 = 1,850 LW/PH
31 @ f/1.8 = 1,848.5 LW/PH
43 @ f/1.9 = 1,774.5 LW/PH
50 @ f/1.4 = 1,669 LW/PH
55 @ f/1.4 = 1,633 LW/PH
77 @ f/1.8 = 1,932.5 LW/PH


I never once said that the corners weren't soft, or that the sigma was anything other than a specialty lens. I was merely refuting the unfounded assertion that the lens was soft and lacked contrast with personal experience. If we're talking overall performance then obviously the FA31 is leagues better. However, the quality of the DA*16-50 and 50-135 wide open at f/2.8 make the performance of primes at f/2.8 and greater irrelevant to me. I was going to buy the FA31, but I opted for the 30 instead having happened across it by accident on PhotoHito. IMO, the bokeh and overall quality of the sigma wide open is as good or better, plus it's 2/3rds of a stop faster.

Horses for courses. If you want a super fast normal for either low light, maximum separation, or to recapture what a 50 1.4 does on film/ff the Sigma 30mm is hard to beat. If you want an all-around technically perfect lens get the DA40 or FA31. There really isn't anything to argue.
10-26-2010, 11:36 PM   #26
Senior Member




Join Date: Feb 2010
Photos: Albums
Posts: 264
Original Poster
QuoteOriginally posted by gnaztee Quote
Not to hijack the thread, but since it came up, anybody want to throw on pics or personal impressions of the Sigmas 24 and 28mm 1.8? I'm in the market for a wider fast lens, as well as a little longer fast lens, and I'm really looking at the 24/28/30 from Sigma as options!
you're not hijacking the thread at all

i'm also curious about the Sigma 24/1.8 and 28/1.8
10-27-2010, 01:08 AM   #27
Veteran Member




Join Date: Jan 2009
Location: Budapest
Posts: 821
QuoteOriginally posted by deadwolfbones Quote
Lately I've been thinking more and more seriously about ditching the FA31 to go back to the Sigma 30.
I've tried FA31 side by side with my Sigma 30 and haven't seen anything that justifies the 3x price difference. I'm sure it's a fine lens and I can understand those who like it, but I'm not going to pay it's ridiculous price. YMMV.


For the OP: I just love this lens, it's glued to my K-m since I purchased it. IQ is amazing even wide open, I use it in f1.4 - 2.2 range. I don't care about the softness of extreme corners and borders, I never put my subjects there so things in those areas are out of focus anyways. Obviously I don't shoot landscapes and architecture with it, for that I use a wider lens (or wide end of my DA 17-70).
I was looking for a prime in 30-40mm range and had to choose from Sigma 30, FA35 and FA43Ltd trio. I chose the Sigma because it was the fastest (the main reason I wanted a prime), cheapest, easiest to purchase and had the best center sharpness wide open. The corner and border softness worried me a little bit, but I quickly realized it doesn't really matter.
10-27-2010, 09:03 AM   #28
Veteran Member




Join Date: Apr 2010
Location: Tennessee
Posts: 2,054
People tend to get worked up because they read that the lens has a fault, as if perfect lenses were the norm. But this is definitely a case of the numerous pros heavily outweighing the one perceived con ( I say perceived because the corner "softness" of this lens can actually be used to great effect and can really help to isolate your subject). Precious few people (reviewers aside) that have tried this lens don't like it. DWB's comment about a possible preference for this lens over the FA31 is not the first time I've read this from someone. The relative bargain price doesn't hurt, either. Do wish our version was HSM like most of the other mounts, though.

More than anything, trust your eyes. The shots posted in this thread (particularly ramair455's B&W shot) refute this lenses naysayers better than any argument could. I had it and sold it, convinced that I needed to complete my FA Ltd. trio. I still want an FA31 (it's lure is strong, my will is weak), but I kinda wish I hadn't sold my Sigma.
10-27-2010, 09:41 AM   #29
Pentaxian
Asahiflex's Avatar

Join Date: Jan 2008
Location: Netherlands
Photos: Gallery
Posts: 2,795
Too much talk, not enough pictures.

Here's one made by a fellow Pentaxian with the Sigma and the K-7:


(Picture was originally posted here: Koud en warm licht)
10-27-2010, 10:18 AM   #30
Senior Member




Join Date: Sep 2009
Location: Okc
Photos: Gallery
Posts: 284
Here are a few glassware shots with the Sigma 28 1.8 @ 1.8-2.0

Its has macro capability that the 30mm doesn't have , however the bokeh is just as nice.





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!
k-mount, pentax lens, sigma 30mm f1.4, slr lens

Similar Threads
Thread Thread Starter Forum Replies Last Post
Request for a sample WAV file from Pentax Optio WP viflan Photographic Technique 2 08-19-2010 01:23 AM
People Sample photo from a wedding Trig Post Your Photos! 1 09-27-2009 07:45 PM
Request a photo of DA21/3.2 on K-M celetron Pentax DSLR Discussion 3 04-14-2009 10:54 PM
sigma 30mm vs. pentax 30mm jay legere Pentax SLR Lens Discussion 6 02-01-2008 04:15 PM
Request for Photo Tramp Ed in GA Post Your Photos! 3 10-18-2006 08:34 PM



All times are GMT -7. The time now is 09:27 PM. | See also: NikonForums.com, CanonForums.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