Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Pentax Lenses

Reply
 
Thread Tools Search this Thread
Old Jan 30, 2008, 9:56 AM   #1
Senior Member
 
Join Date: Feb 2006
Posts: 242
Default

SigmaZoom Telephoto 70-300mm f/4-5.6 APO DG Macro Autofocus Lens for Pentax AF

or

SigmaZoom Wide Angle-Telephoto 28-300mm f/3.5-6.3 DG Macro Autofocus Lens f/ Pentax AF SLR



Both are the same price and they will compliment the kit lense on the k10.
Angel L. is offline   Reply With Quote
Sponsored Links
Old Jan 30, 2008, 10:28 AM   #2
Senior Member
 
mtngal's Avatar
 
Join Date: Nov 2005
Location: Frazier Park, CA
Posts: 16,052
Default

Definitely get the 70-300 APO. You already have the kit lens, you don't need to cover that focal length again.

I'm only speaking from what I've seen posted here (I have no experience with either lens) but people routinely post excellent pictures here taken with the 70-300. I'vemostly seen people post complaints about the 28-300 - its soft and makes too many compromises (it is extremely difficult for a lens to be sharp for both wide angle and telephoto). In general, the longer focal range a lens covers, the worse it gets (the one exception appears to be the relatively newTamron 18-250).
mtngal is offline   Reply With Quote
Old Jan 30, 2008, 11:29 AM   #3
TDN
Senior Member
 
TDN's Avatar
 
Join Date: Jun 2006
Posts: 1,288
Default

the 70-300mm will be MUCH better at 300mm than the 28-300mm.

The reason is that the 28-300 has a much bigger zoom range (~10x), and for that the engineers will have had to make some compromises.

The 70-300mm APO has been known to produce some great results, I'd say go for it.

Tom
TDN is offline   Reply With Quote
Old Feb 6, 2008, 8:40 AM   #4
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

70-300 APO!!

Dawg
bigdawg is offline   Reply With Quote
Old Mar 3, 2008, 8:51 AM   #5
Member
 
Join Date: Nov 2007
Posts: 71
Default

I am in kinda the same boat. I am trying to choose between:


Tamron - AF70-300mm F/4-5.6 Di LD Macro 1:2

Sigma 70-300mm F4-5.6 APO DG MACRO Lens

What does the APO mean? The Tamron is $80 less then the Sigma. This will be my first new lense besides the 18- 55 kit lense.

Is this a good lense:

SMC PENTAX FA J 75-300mm F4.5-5.8 AL.

When comparing lenses between a film slr and a digital lens how does it work (ie when using a 80 - 105mm slr lens on a dslr camera do you times the focal length by 1.5 or is it when you us a dslr lense on a slr film camera that you times it 1.5)?
GrahamM is offline   Reply With Quote
Old Mar 3, 2008, 11:30 AM   #6
Senior Member
 
snostorm's Avatar
 
Join Date: Jan 2004
Location: Chicago Suburb, IL, USA
Posts: 2,770
Default

GrahamM wrote:
Quote:
I am in kinda the same boat.* I am trying to choose between:


Tamron - AF70-300mm F/4-5.6 Di LD Macro 1:2

Sigma 70-300mm F4-5.6 APO DG MACRO Lens

What does the APO mean?* The Tamron is $80 less then the Sigma.* This will be my first new lense besides the 18- 55 kit lense.

Is this a good lense:

SMC PENTAX FA J 75-300mm F4.5-5.8 AL.

When comparing lenses between a film slr and a digital lens how does it work (ie when using a 80 - 105mm slr lens on a dslr camera do you times the focal length by 1.5 or is it when you us a dslr lense on a slr film camera that you times it 1.5)?
Hi Graham,

Sigma's APO (Apochromatic)= Tamron's LD (Low Dispersion)= Tokina's SD (Super low Dispersion)= Pentax's ED (Extra low Dispersion).

When you see these terms, it means that the lens design includes at least one lens element made of special glass which helps to correct CA -- Chromatic Aberration (color fringing, caused when a lens focuses different colors (frequencies) at slightly different points in the image.

APO (or LD, etc) glass is considerably more expensive than standard optical glass, so this shows an extra effort by the lens manufacturer to control CA, but different designs succeed to different degrees.

The Tamron and Sigma lenses that you named are rated very similarly (and pretty highly), AFAIK, so you're probably good with either. IIRC, the FA J Pentax lens is not considered to be as sharp as either the Sigma or Tamron, and its build quality is not as good (it's offered as a budget class lens).

I'd go with either the Sigma or Tamron.

Scott
snostorm is offline   Reply With Quote
Old Mar 3, 2008, 5:00 PM   #7
Senior Member
 
Trojansoc's Avatar
 
Join Date: Jan 2007
Location: Hot Springs, AR
Posts: 3,723
Default

snostorm wrote:
Quote:
GrahamM wrote:
Quote:
I am in kinda the same boat. I am trying to choose between:


Tamron - AF70-300mm F/4-5.6 Di LD Macro 1:2

Sigma 70-300mm F4-5.6 APO DG MACRO Lens

What does the APO mean? The Tamron is $80 less then the Sigma. This will be my first new lense besides the 18- 55 kit lense.
Hi Graham,

Sigma's APO (Apochromatic)= Tamron's LD (Low Dispersion)= Tokina's SD (Super low Dispersion)= Pentax's ED (Extra low Dispersion).

When you see these terms, it means that the lens design includes at least one lens element made of special glass which helps to correct CA -- Chromatic Aberration (color fringing, caused when a lens focuses different colors (frequencies) at slightly different points in the image.

APO (or LD, etc) glass is considerably more expensive than standard optical glass, so this shows an extra effort by the lens manufacturer to control CA, but different designs succeed to different degrees.

The Tamron and Sigma lenses that you named are rated very similarly (and pretty highly), AFAIK, so you're probably good with either. IIRC, the FA J Pentax lens is not considered to be as sharp as either the Sigma or Tamron, and its build quality is not as good (it's offered as a budget class lens).

I'd go with either the Sigma or Tamron.

Scott
I have no experience with the Sigma or the Pentax, but I do have the Tamron 70-300, and it does have a serious problem with CA, particularly when shooting up into trees for birds. I might just have a bad copy of it, but I've been disappointed on this score.

So, I'd probably suggest the Sigma, based on the recommendations I've read on this forum.

Paul
Trojansoc is offline   Reply With Quote
Old Mar 3, 2008, 6:50 PM   #8
Senior Member
 
bigdawg's Avatar
 
Join Date: Feb 2005
Location: Thach Alabama
Posts: 14,981
Default

I have been posting quite a few photos with a vivitar lens made in the 70's and it has no APO lens..Lots of CA in those photos...I have been posting a lot of photos with the Sigma 50-500 APO DG EX lens and the CA is almost totally controlled by that lens...Check my recent posts from Big Spring Park in huntsville. Like this one

http://forums.steves-digicams.com/fo...mp;forum_id=80



Dawg
bigdawg is offline   Reply With Quote
Old Mar 3, 2008, 7:54 PM   #9
Member
 
Join Date: Nov 2007
Posts: 71
Default

I want to get a nice big lense like that also Dawg, but gotta break the wifey in slowly :lol:.

My main purpose for this lense will be wildlife and ships out in the lake ( I live at the mouth of the St. Clair river ).

I am fairly new to this stuff, so what does CA mean?
GrahamM is offline   Reply With Quote
Old Mar 3, 2008, 11:32 PM   #10
Senior Member
 
Join Date: Jul 2006
Location: Tumbleweed, Arizona
Posts: 1,381
Default

Hi GrahamM,

On your question concerning the SMC PENTAX FA J 75-300mm F4.5-5.8 AL. I was originally looking for the Pentax FA 80-320 f4.5-5.5 and made a mistake and wound up with bidding on and winning the FA J 75-300mm F4.5-5.8 AL. Its an ok lens, however I would have rather had the 80-320.

Actually, I am hunting for the Tokina 80-400, but that is another story (and yes, I still like the wide end rather than the telephoto end).

So, the story is - that last Saturday a bit after 5pm, I had just sat down and was watching some whatever on TV when there was this roar overhead and my wife, out in the kitchen, said that - what was that? I went out side, knowing exactly what it was and here are are two F-18's wing on wing, with their gear down on final going into the small airport nearby. Its very rarely that we get any traffic from the municipal airport, so I got in the truck - picking up my camera to get some pictures of the "birds on ground" in that I missed the "birds in flight".

Here are some pictures of the 75-300 at 300, so you can decide. The light was poor, as the sun was setting, and these were just targets of opportunity.



Attached Images
 
interested_observer is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 10:28 AM.