Sigma 120-400mm f/4.5-5.6 for Pentax

**Aristophanes** · 05-18-2010, 07:25 PM

You might have noticed this announcement here:

Sigma releases 120-400mm f/4.5-5.6 for Sony & Pentax: Digital Photography Review

And wondered (as I am) is this the big zoom for me?

A nice, honest, objective field test here from a Canon sample:

Gear Darwin Wiggett

High praise. The Amazon review corps appear to like but for those who downgrade their rating wit Sigma's QC issues that crop up often enough to give a consumer pause. ONe nice thing about Pentax being late to the party is that early releases have perhaps not been tweaked for optimum design and assembly, so we may avoid a lot of earlier errors other brands are exposed to.

Considering this lens is going on pre-order for US$899, might be a lens to keep an eye on where genuine Pentax brand is simply not there.

(Side-note: Anyone else note how the newer Sigma's do not work with their existing K-mount teleconverters? Could someone please make a decent TC that works for the K-mount?)

pinholecam · 05-18-2010, 07:48 PM

I don't understand this lens as to how it fits in when there is already the 150-500 and 50-500 for absolute reach. For shorter there are the many 70-300, DA55-300mm options.

**Aristophanes** · 05-18-2010, 08:07 PM

Originally posted by pinholecam

I don't understand this lens as to how it fits in when there is already the 150-500 and 50-500 for absolute reach. For shorter there are the many 70-300, DA55-300mm options.

Didn't you just answer your own question?

Slightly better IQ as it reaches less, and better range with equivalent IQ to the 300's (aperture being near constant between them). The 120-400 looks to get better reviews than either of the other Sigma's mentioned and is less expensive by a considerable amount over the 50-500. The 120-400 appears to be considerably more compact as well. The DA 55-300 is really not in the same category. This looks to complement a 70-200 2.8, also on my list.

pinholecam · 05-18-2010, 10:38 PM

Originally posted by Aristophanes

Didn't you just answer your own question?

Slightly better IQ as it reaches less, and better range with equivalent IQ to the 300's (aperture being near constant between them). The 120-400 looks to get better reviews than either of the other Sigma's mentioned and is less expensive by a considerable amount over the 50-500. The 120-400 appears to be considerably more compact as well. The DA 55-300 is really not in the same category. This looks to complement a 70-200 2.8, also on my list.

Ahh! I think I missed the comparisons point initially that its a Sigma 100-300/4 or DA*300/4 like replacement based on the review you posted. Well it could be...

I was thinking more in the line that if I needed a 400mm, I'd most likely need 500mm (eg.birds); which is how a 50-500 comes in. If I needed shorter, I'd opt for a cheaper 55-300mm type lens (of course the image quality my differ a bit)

JP_Seattle · 06-19-2010, 10:53 AM

Originally posted by Aristophanes

This looks to complement a 70-200 2.8, also on my list.

Why would someone get both a 70-200mm 2.8 and the 120-400mm lenses, when you could just put a 2x TC on your 70-200mm 2.8 and make it a 140-400mm 5.6?

I am interested in buying a new lens that covers the extra reach of 400 or 500mm so this is one question I have come across myself. Is the image quality superior of using a Sigma 120-400mm or even the old 135-400mm over a Sigma 70-200mm 2.8 with a 2x TC. Is the image quality identical? ... or maybe even better leaning towards the 70-200 with TC?

The 70-200mm with TC would definitely give you more flexibility and a really fast zoom without the TC, but there has to be a reason why they would market the 135-400mm and now the 120-400mm lenses. Someone help me out and let me know what it is.

Lastly, anyone used any of these Sigma -400mm zooms and compared them to the Sigma APO AF 400mm prime or Tokina AT-X 400mm AF prime? I already own the DA 55-300mm and I am pretty happy with that, just could use a little more reach.

RichardLev · 06-25-2010, 09:42 AM

Sigma has issued a notice warning customers of a 'potential autofocus defect' in some of its recently released telephoto lenses. The problem affects a some examples of the APO 50-500mm F4.5-6.3 DG OS HSM, APO 120-400mm F4.5-5.6 DG OS HSM and APO 150-500mm F5-6.3 DG OS HSM lenses. The company has listed the serial numbers of lenses that could be affected - owners experiencing problems with any of these lenses are being offered a free collection, inspection and service.

Press Release: Auto focusing issue affects limited number of
Sigma telezoom lenses

After thorough investigation, we have ascertained that some APO 50-500mm F4.5-6.3 DG OS HSM, APO 120-400mm F4.5-5.6 DG OS HSM and APO 150-500mm F5-6.3 DG OS HSM lenses, produced recently, may have a potential autofocus defect.
This issue could possibly occur in some lenses within the following range of serial numbers:
List of lenses requiring the modification
APO 50-500mm F4.5-6.3 DG OS HSM: Serial Numbers between 10633051 and 10972000
APO 120-400mm F4.5-5.6 DG OS HSM: Serial Numbers between 10574001 and 10972000
APO 150-500mm F5-6.3 DG OS HSM: Serial Numbers between 10674301 and 10972000
This is a limited problem that will not occur in any lenses other than those specifically listed above.
Support for this problem
To overcome this issue, we will be offering our customers a modification service, free of charge. If one of our customers is experiencing an autofocus issue with one of the above lenses, we will rectify the situation through the help of our local authorized Sigma Service Stations.
We deeply apologize if any inconvenience has been caused to our customers.　
For further information, please contact your nearest authorized Sigma Service Station.
World Network - SIGMA CORPORATION

reeftool · 06-26-2010, 09:27 AM

Well, thats probably the answer to the question brought up on some other threads as to why there are no new Bigma's available. At least they are addressing the problem. It may be worthwhile to make a note of those serial numbers as many of these lenses probably won't get returned in the recall but will end up on Ebay or Craigslist.

05-18-2010, 07:25 PM	#1
Aristophanes Site Supporter Join Date: Jul 2008 Location: Rankin Inlet, Nunavut Photos: Albums Posts: 3,948	Sigma 120-400mm f/4.5-5.6 for Pentax You might have noticed this announcement here: Sigma releases 120-400mm f/4.5-5.6 for Sony & Pentax: Digital Photography Review And wondered (as I am) is this the big zoom for me? A nice, honest, objective field test here from a Canon sample: Gear Darwin Wiggett High praise. The Amazon review corps appear to like but for those who downgrade their rating wit Sigma's QC issues that crop up often enough to give a consumer pause. ONe nice thing about Pentax being late to the party is that early releases have perhaps not been tweaked for optimum design and assembly, so we may avoid a lot of earlier errors other brands are exposed to. Considering this lens is going on pre-order for US$899, might be a lens to keep an eye on where genuine Pentax brand is simply not there. (Side-note: Anyone else note how the newer Sigma's do not work with their existing K-mount teleconverters? Could someone please make a decent TC that works for the K-mount?)

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05-18-2010, 07:48 PM	#2
pinholecam Pentaxian Join Date: Oct 2009 Location: North Photos: Gallery Posts: 4,706	I don't understand this lens as to how it fits in when there is already the 150-500 and 50-500 for absolute reach. For shorter there are the many 70-300, DA55-300mm options.

05-18-2010, 08:07 PM	#3
Aristophanes Site Supporter Join Date: Jul 2008 Location: Rankin Inlet, Nunavut Photos: Albums Posts: 3,948 Original Poster	Originally posted by pinholecam I don't understand this lens as to how it fits in when there is already the 150-500 and 50-500 for absolute reach. For shorter there are the many 70-300, DA55-300mm options. Didn't you just answer your own question? Slightly better IQ as it reaches less, and better range with equivalent IQ to the 300's (aperture being near constant between them). The 120-400 looks to get better reviews than either of the other Sigma's mentioned and is less expensive by a considerable amount over the 50-500. The 120-400 appears to be considerably more compact as well. The DA 55-300 is really not in the same category. This looks to complement a 70-200 2.8, also on my list.

05-18-2010, 10:38 PM	#4
pinholecam Pentaxian Join Date: Oct 2009 Location: North Photos: Gallery Posts: 4,706	Originally posted by Aristophanes Didn't you just answer your own question? Slightly better IQ as it reaches less, and better range with equivalent IQ to the 300's (aperture being near constant between them). The 120-400 looks to get better reviews than either of the other Sigma's mentioned and is less expensive by a considerable amount over the 50-500. The 120-400 appears to be considerably more compact as well. The DA 55-300 is really not in the same category. This looks to complement a 70-200 2.8, also on my list. Ahh! I think I missed the comparisons point initially that its a Sigma 100-300/4 or DA*300/4 like replacement based on the review you posted. Well it could be... I was thinking more in the line that if I needed a 400mm, I'd most likely need 500mm (eg.birds); which is how a 50-500 comes in. If I needed shorter, I'd opt for a cheaper 55-300mm type lens (of course the image quality my differ a bit)

06-19-2010, 10:53 AM	#5
JP_Seattle Senior Member Join Date: Jan 2010 Location: Seattle, WA Photos: Albums Posts: 206	Originally posted by Aristophanes This looks to complement a 70-200 2.8, also on my list. Why would someone get both a 70-200mm 2.8 and the 120-400mm lenses, when you could just put a 2x TC on your 70-200mm 2.8 and make it a 140-400mm 5.6? I am interested in buying a new lens that covers the extra reach of 400 or 500mm so this is one question I have come across myself. Is the image quality superior of using a Sigma 120-400mm or even the old 135-400mm over a Sigma 70-200mm 2.8 with a 2x TC. Is the image quality identical? ... or maybe even better leaning towards the 70-200 with TC? The 70-200mm with TC would definitely give you more flexibility and a really fast zoom without the TC, but there has to be a reason why they would market the 135-400mm and now the 120-400mm lenses. Someone help me out and let me know what it is. Lastly, anyone used any of these Sigma -400mm zooms and compared them to the Sigma APO AF 400mm prime or Tokina AT-X 400mm AF prime? I already own the DA 55-300mm and I am pretty happy with that, just could use a little more reach.

06-25-2010, 09:42 AM	#6
RichardLev New Member Join Date: May 2010 Location: Northern New Jersey Posts: 5	Sigma has issued a notice warning customers of a 'potential autofocus defect' in some of its recently released telephoto lenses. The problem affects a some examples of the APO 50-500mm F4.5-6.3 DG OS HSM, APO 120-400mm F4.5-5.6 DG OS HSM and APO 150-500mm F5-6.3 DG OS HSM lenses. The company has listed the serial numbers of lenses that could be affected - owners experiencing problems with any of these lenses are being offered a free collection, inspection and service. Press Release: Auto focusing issue affects limited number of Sigma telezoom lenses After thorough investigation, we have ascertained that some APO 50-500mm F4.5-6.3 DG OS HSM, APO 120-400mm F4.5-5.6 DG OS HSM and APO 150-500mm F5-6.3 DG OS HSM lenses, produced recently, may have a potential autofocus defect. This issue could possibly occur in some lenses within the following range of serial numbers: List of lenses requiring the modification APO 50-500mm F4.5-6.3 DG OS HSM: Serial Numbers between 10633051 and 10972000 APO 120-400mm F4.5-5.6 DG OS HSM: Serial Numbers between 10574001 and 10972000 APO 150-500mm F5-6.3 DG OS HSM: Serial Numbers between 10674301 and 10972000 This is a limited problem that will not occur in any lenses other than those specifically listed above. Support for this problem To overcome this issue, we will be offering our customers a modification service, free of charge. If one of our customers is experiencing an autofocus issue with one of the above lenses, we will rectify the situation through the help of our local authorized Sigma Service Stations. We deeply apologize if any inconvenience has been caused to our customers.　 For further information, please contact your nearest authorized Sigma Service Station. World Network - SIGMA CORPORATION

06-26-2010, 09:27 AM	#7
reeftool Pentaxian Join Date: Dec 2007 Location: Upstate New York Photos: Gallery \| Albums Posts: 9,554	Well, thats probably the answer to the question brought up on some other threads as to why there are no new Bigma's available. At least they are addressing the problem. It may be worthwhile to make a note of those serial numbers as many of these lenses probably won't get returned in the recall but will end up on Ebay or Craigslist.