Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-07-2011, 08:37 PM   #1
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Quality vs AF Speed

So after several hours browsing the internet I got the following competitors left in the ring, to be used on a K-5:



Sigma 100-300mm F4 EX DG APO (AF Lens) + 1.4x TC

Sigma 120-400mm F4.5-5.6 DG OS APO HSM no TC

Sigma 50-500mm F4-6.3 EX DG APO (AF Lens) no TC

Sigma 150-500mm F5-6.3 DG APO HSM no TC





My question is which one of them is the best to be used with those TCs?

My main priority is IQ, but as I'm not going to carry a tripod or monopod around AF Speed is extremly important as well. So forget about price, utility, weight and all that stuff, I already have a good mid range lens.

Few minutes ago I saw Piotr's pictures using the 100-300 and I have no words to describe how sharp that thing is, his pictures were more worth than a full review to me, since he took many shots with different aperture, ISO, FLs and w/ or w/o his 1.4x TC and all of them look REALLY beautiful.

You can have a look at his pictures in here:

Mauritius birds Photo Gallery by Piotr Sobolewski at pbase.com

The only thing which made me not choose 100-300 yet was his AF Speed, which I would like to confirm if it's fast and steady enough to take similar shots hand holding the camera.

I do know that Sigma 70-200 and DA* 60-250 have the fastest focus. But as the 100-300 is cheapper than the DA* and still has longer reach. Therefore, I'm here to ask what's your verdict?


Thanks for your time in advance! =D

UPDATE:

I had to change the TCs to 2x to balance the zoom range, but yes, we will have to take in account the slight image deterioration :x

I would be much happier if I could just find an album just like Pitr's from the other lenses, so I could compare them. However, I'm still looking for those...

Chart updated.


Last edited by Thales454; 05-07-2011 at 10:49 PM.
05-07-2011, 08:47 PM   #2
Pentaxian




Join Date: Nov 2008
Location: Bangalore
Photos: Gallery
Posts: 2,450
I don't have the link handy but someone tried out Sigma 100-300mm F4 vs 70-200+TC and 100-300 was overall better - at least the AF was much faster.
05-07-2011, 08:49 PM   #3
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Original Poster
QuoteOriginally posted by yusuf Quote
I don't have the link handy but someone tried out Sigma 100-300mm F4 vs 70-200+TC and 100-300 was overall better - at least the AF was much faster.
Can you recall if it was a member from our comunity?
05-07-2011, 08:58 PM   #4
Veteran Member




Join Date: Jan 2009
Location: Canada
Posts: 1,255
QuoteOriginally posted by Thales454 Quote
So after several hours browsing the internet I got the following competitors left in the ring, to be used on a K-5:



Pentax-DA* 60-250mm F4 ED [IF] SDM

Tamron 70-200mm F2.8 DI LD Macro

Sigma 70-200mm F2.8 EX DG APO Macro HSM II

Sigma 100-300mm F4 EX DG APO (AF Lens)



My question is which one of them is the best to be used with a 1.4x TC?

My main priority is IQ, but as I'm not going to carry a tripod or monopod around AF Speed is extremly important as well. So forget about price, utility, weight and all that stuff, I already have a good mid range lens.

Few minutes ago I saw Piotr's pictures using the 100-300 and I have no words to describe how sharp that thing is, his pictures were more worth than a full review to me, since he took many shots with different aperture, ISO, FLs and w/ or w/o his 1.4x TC and all of them look REALLY beautiful.

You can have a look at his pictures in here:

Mauritius birds Photo Gallery by Piotr Sobolewski at pbase.com

The only thing which made me not choose 100-300 yet was his AF Speed, which I would like to confirm if it's fast and steady enough to take similar shots hand holding the camera.

I do know that Sigma 70-200 and DA* 60-250 have the fastest focus. But as the 100-300 is cheapper than the DA* and still has longer reach, I'm here to ask what's your verdict?


Thanks for your time in advance! =D
My verdict is you should get DA 21, DA 40, DA 70 and DA* 300 f/4.

05-07-2011, 09:00 PM   #5
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Original Poster
QuoteOriginally posted by asdf Quote
My verdict is you should get DA 21, DA 40, DA 70 and DA* 300 f/4.
Thanks for the advice, however I'm looking for Zooms only
05-07-2011, 09:04 PM   #6
Veteran Member




Join Date: Jan 2009
Location: Canada
Posts: 1,255
QuoteOriginally posted by Thales454 Quote
Thanks for the advice, however I'm looking for Zooms only
Fatima came across Nasruddin in the living room scooting around on his hands and knees, with his turbaned head bumping around, searching intently. She asked, “What are you looking for, Nasruddin?”

“I lost my ring in the basement.”

“Then why are you looking for it up here?”

“I looked for it down there, but it was so dark there that I couldn’t see a thing. Since I knew the light here is better, I came upstairs. I still can’t find it, so next I’ll go outside, where the light is even better, and maybe I’ll find it there.”
05-07-2011, 09:08 PM   #7
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Original Poster
QuoteOriginally posted by asdf Quote
“I looked for it down there, but it was so dark there that I couldn’t see a thing. Since I knew the light here is better, I came upstairs. I still can’t find it, so next I’ll go outside, where the light is even better, and maybe I’ll find it there.”
Yes, I got your point Fatima

But I'm also a traveler in the mean time, so I don't have the necessary time to swap lenses that often and that's the main reason why I've previously asked about those specific zoom lenes
05-07-2011, 09:17 PM   #8
Veteran Member




Join Date: Jan 2009
Location: Canada
Posts: 1,255
QuoteOriginally posted by Thales454 Quote
Yes, I got your point Fatima

But I'm also a traveler in the mean time, so I don't have the necessary time to swap lenses that often and that's the main reason why I've previously asked about those specific zoom lenes


Well, I do own DA* 300 f/4 and not DA* 60-250, but based on the sample pictures, tests and pretty much a general consensus, DA* 60-250 is excellent optically. The problem with both HSM and SDM is potential failure. I've had one SDM motor failure (not on DA* 300 f/4 though) and had it replaced.

05-07-2011, 09:30 PM   #9
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Original Poster
QuoteOriginally posted by asdf Quote
The problem with both HSM and SDM is potential failure.
Ic... Well, I guess it's something that I will have to deal with :x

Could you give us an input about DA* 60-250 + TC ?

I've found the following user review in the Sigma 150-500 (which has a fairly inferior IQ) page:


"Generally I stick with Pentax lenses, but with brick wall at 300mm, I was left with few options. I did try teleconverters on my DA* 60-250 and 300, but the results were disappointing so I bought the Sigma 150-500.
"


Should I guess he was using a bad TC or having some kind of technical issues?

Last edited by Thales454; 05-07-2011 at 09:37 PM.
05-07-2011, 09:36 PM   #10
Veteran Member




Join Date: Jan 2009
Location: Canada
Posts: 1,255
QuoteOriginally posted by Thales454 Quote
Ic... Well, I guess it's something that I will have to deal with :x

Could you give us an input about DA* 60-250 + TC ?

I've found the following user review in the Sigma 150-500 (which has a fairly inferior IQ) page:


"Generally I stick with Pentax lenses, but with brick wall at 300mm, I was left with few options. I did try teleconverters on my DA* 60-250 and 300, but the results were disappointing so I bought the Sigma 150-500.
"


Should I guess he was using a bad TC or having some kind of technical issues?
A TC will degrade image quality. Also, the TC will definitely negatively affect auto-focus speed because it makes the image dimmer. I've had cameras hunt far more frequently with a teleconverter, on cloudy days especially. If you start with a faster lens (i.e., 300 f/2.8) and add a quality teleconverter, you'll have less trouble with AF speed.
05-07-2011, 09:38 PM   #11
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Original Poster
QuoteOriginally posted by asdf Quote
A TC will degrade image quality. Also, the TC will definitely negatively affect auto-focus speed because it makes the image dimmer. I've had cameras hunt far more frequently with a teleconverter, on cloudy days especially. If you start with a faster lens (i.e., 300 f/2.8) and add a quality teleconverter, you'll have less trouble with AF speed.
Alright, thanks very much for your time =D
05-07-2011, 10:04 PM   #12
Veteran Member




Join Date: Jun 2010
Location: Marina CA
Posts: 344
It's my understanding that current digital SLR cameras won't auto-focus with an f/8 lens. An f/4 lens with a doubler becomes an f/8 lens and may not auto-focus at all. Has anyone tried the AF at f/8 ? Aside from better quality I think that may be why people use a 1.4x converter with an f/4 lens.
05-07-2011, 10:07 PM   #13
Junior Member
Thales454's Avatar

Join Date: May 2011
Location: Rio Grande do Sul / Porto Alegre
Posts: 48
Original Poster
QuoteOriginally posted by pentaxus Quote
It's my understanding that current digital SLR cameras won't auto-focus with an f/8 lens. An f/4 lens with a doubler becomes an f/8 lens and may not auto-focus at all. Has anyone tried the AF at f/8 ? Aside from better quality I think that may be why people use a 1.4x converter with an f/4 lens.
This have been currently stated by a user in the 100-300 page:

"I mostly use this lens for sports and at air shows. As with the 70-200, this lens also works very will with the Sigma EX teleconverters. The Sigma web site states that you lose auto focus capability when using the 2x converter with this lens. That has not been my experience. Auto focus works just fine. Must have been something the lawyers made them say. You know, to protect themselves."

I guess some of them don't have this issue :x
05-07-2011, 10:14 PM   #14
Veteran Member




Join Date: Jan 2009
Location: Canada
Posts: 1,255
QuoteOriginally posted by Thales454 Quote
This have been currently stated by a user in the 100-300 page:

"I mostly use this lens for sports and at air shows. As with the 70-200, this lens also works very will with the Sigma EX teleconverters. The Sigma web site states that you lose auto focus capability when using the 2x converter with this lens. That has not been my experience. Auto focus works just fine. Must have been something the lawyers made them say. You know, to protect themselves."

I guess some of them don't have this issue :x
As I mentioned above, it depends on light conditions, too. If you shoot high contrast targets on sunny days, you'll have less problems.
05-08-2011, 02:07 AM   #15
Forum Member




Join Date: Jul 2007
Posts: 77
Thales, apparently you're overseas (at least from a US perspective) but where do you plan on getting the Sigma 100-300? I'm looking for a copy of this lens.
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!
af, apo, dg, k-mount, lens, look, pentax lens, pictures, shots, sigma, slr lens, tc
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Is the K-x the same video quality as K-7? justtakingpics Video and Pentax HDSLRs 2 04-23-2010 10:43 PM
Looking for a good quality dardjiskien Pentax SLR Lens Discussion 4 04-07-2010 02:13 AM
Printing Quality neilj Digital Processing, Software, and Printing 5 12-26-2009 09:36 AM
K-x vs K-m JPEG quality deadwolfbones Pentax DSLR Discussion 8 11-21-2009 08:47 PM
DA* 16-50 how to test quality Burgerbrater Pentax SLR Lens Discussion 32 10-23-2009 01:35 PM



All times are GMT -7. The time now is 10:30 AM. | 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