DA* 55mm/1.4--Erratic focusing

RonHendriks1966 · 02-21-2011, 01:39 PM

Well it is a wonderfull lens, so getting a good copy is something that you will enjoy for years to come.

robgo2 · 02-23-2011, 02:11 PM

Well, I just finished testing a third copy of the DA* 55/1.4 from Amazon. It backfocuses more severely than the first two. I cannot correct it with +10 AF adjustment. So, back it goes, this time for a refund. As I said in an earlier post, I have not experienced this problem with any of my other Pentax lenses, so I think that Pentax has a serious QC issue with this particular lens. Too bad, as I really need something like it for portraiture. If only the Sigma 50/1.4 were not so big.

Rob

Class A · 02-23-2011, 05:08 PM

Too bad it didn't work out.

The Sigma is only 2mm longer (well and quite a bit fatter in diameter).

RonHendriks1966 · 02-24-2011, 11:47 AM

Voightlander Nokton 58mm is also an option if you can find one. Or FA43mm or FA77mm.

robgo2 · 02-24-2011, 04:56 PM

Originally posted by RonHendriks1966

Voightlander Nokton 58mm is also an option if you can find one. Or FA43mm or FA77mm.

The Nokton is manual focus, and the 43 Limited is relatively close in focal length to my 31 Limited and also a bit short for a portrait lens (although certainly not bad.) I already own the 77 Limited. I have decided to give the DA* 55/1.4 one more chance and have ordered one from B&H. I am also giving more consideration to the Sigma 50/1.4, despite its large size and weight. I am really pissed and disappointed that Pentax cannot produce a lens that focuses accurately, especially one that is super fast and not inexpensive.

Rob

Egg Salad · 02-25-2011, 07:57 AM

I'd also recommend the Sigma because it's the closest choice next to the DA* 55. But unfortunately QC is no better than with Pentax, more likely worse.
I bought my copy used, so QC was already done by the previous owner who had to get through 3 lenses himself...
Quality wise the Nokon is probably the best choice - but well, no AF.

RonHendriks1966 · 02-25-2011, 09:02 AM

Originally posted by robgo2

The Nokton is manual focus, and the 43 Limited is relatively close in focal length to my 31 Limited and also a bit short for a portrait lens (although certainly not bad.) I already own the 77 Limited. I have decided to give the DA* 55/1.4 one more chance and have ordered one from B&H.

So you actually have no need at all for an extra lens

Or to complete it get next to all those fine lenses the FA*85mm/f1.4 just for fun.

robgo2 · 02-25-2011, 10:03 AM

Originally posted by RonHendriks1966

So you actually have no need at all for an extra lens

Or to complete it get next to all those fine lenses the FA*85mm/f1.4 just for fun.

Ron,

My interest in a 50ish lens is to fill the portraiture sweet spot of 75-85mm in terms of 35mm format. I do own a DA* 16-50, but I would like a faster, better prime lens for this special purpose. I guess I have a case of LBA, which is not like me, as I have never been much of a gear head. I just like to take pictures and then work the hell out of them in PP. To me, that is the fun part of photography.

www.rgoldsteinphotography.com

Rob

robgo2 · 02-25-2011, 10:08 AM

Originally posted by Egg Salad

I'd also recommend the Sigma because it's the closest choice next to the DA* 55. But unfortunately QC is no better than with Pentax, more likely worse.
I bought my copy used, so QC was already done by the previous owner who had to get through 3 lenses himself...
Quality wise the Nokon is probably the best choice - but well, no AF.

If you read the user reviews of the Sigma 50/1.4 (Nikon and Canon mounts) over at B&H, you will find some complaints about focusing accuracy, but overwhelmingly, people love this lens and compare it favorably to anything that Nikon and Canon have to offer. I may ultimately give it a try, but it seems ridiculously large and heavy.

Rob

**Rondec** · 02-25-2011, 11:54 AM

Originally posted by robgo2

If you read the user reviews of the Sigma 50/1.4 (Nikon and Canon mounts) over at B&H, you will find some complaints about focusing accuracy, but overwhelmingly, people love this lens and compare it favorably to anything that Nikon and Canon have to offer. I may ultimately give it a try, but it seems ridiculously large and heavy.

Rob

Particularly considering that the DA *55 is also a full frame lens.

Egg Salad · 02-25-2011, 01:09 PM

I forgot about the focus issues. But I'd file them under poor QC as well.
It's not like I had an assistant who carries my stuff for me but I don't care about its size or weight. At all.
I don't have it too long yet but from what I already can say is that this lens doesn't create anything you have never seen before. But yeah, it does a very nice job being a great performer.
Shaprness/resolution is there - even wide open (at intermediate distances) - the only thing that spoils it are its rather visible CAs.

Since no one has mentioned it yet, I'll also add that it focuses considerably faster than the Pentax. The DA* is even said to be clearly slower than the F/FA version (ok, I have to admit that my F 1:1.7 50mm focuses crazily fast - but it's also loud).
I haven't seriously compared the F to the new Sigma but if anything then the Sigma isn't much slower. May very likely be just as fast as the F/FA.

Also incomprehensible to me is that no one has (ever) metioned the Sigma HSM lenses offer a gear transmission ratio of 1:2. Turning the focus ring for 20° actually moves the distance scale 10°. A thing of genius.
Since I saw Sigma has this feature the focusing on my DA* 16-50 totally sucks to me. And the DA* 55 may not be any different.
On my Sigma 50, the focus ring moves rather stiff but that's still better than this dead feeling on the 16-50.

RonHendriks1966 · 02-25-2011, 01:53 PM

Originally posted by Egg Salad

Since no one has mentioned it yet, I'll also add that it focuses considerably faster than the Pentax. The DA* is even said to be clearly slower than the F/FA version

This is true, the DA*55mm is the slowest of all my lenses in focussing. Since I got the K-5 the difference is even greater because all other lenses gaint speed on the new body. Part of the problem is also a big turn of the focusring.

But it can be very good on the spot.

Originally posted by robgo2

My interest in a 50ish lens is to fill the portraiture sweet spot of 75-85mm in terms of 35mm format. I do own a DA* 16-50, but I would like a faster, better prime lens for this special purpose. I guess I have a case of LBA, which is not like me, as I have never been much of a gear head. I just like to take pictures and then work the hell out of them in PP. To me, that is the fun part of photography.

Nice pictures. Then again I would make a break for adding the FA*85mm to your lens-line-up since this is also an excellent portraitlens (on the long site).

K-7 and FA*85mm at f2.0

Egg Salad · 02-25-2011, 02:29 PM

Being slow doesn't mean it can't be good. But in certain circumstances fast AF just may be critical (most complaints were about focus speed from MFD to infinity which isn't that important in actual use, though).

I couldn't find a definite number so can anybody tell me what the actual focus throw is on the DA* 55?
On the Sigma it is 90° (+-2°) but for the AF it's just 45° focus throw which makes it so fast. Moving cats are still a challenge it can't win...

RonHendriks1966 · 02-25-2011, 03:27 PM

I think it is some 110-120 degrees. Not messured it.

Egg Salad · 02-25-2011, 03:44 PM

No wonder it's slower than the Sigma then.
Just checked: the F 1:1.7 50mm offers ~160°, the SMC Pentax 1:1.4/50 190-200°.
Thanks.

02-23-2011, 02:11 PM	#17
robgo2 Veteran Member Join Date: Jan 2007 Location: New Mexico Photos: Albums Posts: 1,125 Original Poster	Third copy no better than the others Well, I just finished testing a third copy of the DA* 55/1.4 from Amazon. It backfocuses more severely than the first two. I cannot correct it with +10 AF adjustment. So, back it goes, this time for a refund. As I said in an earlier post, I have not experienced this problem with any of my other Pentax lenses, so I think that Pentax has a serious QC issue with this particular lens. Too bad, as I really need something like it for portraiture. If only the Sigma 50/1.4 were not so big. Rob Last edited by robgo2; 02-23-2011 at 03:32 PM.

02-25-2011, 10:03 AM	#23
robgo2 Veteran Member Join Date: Jan 2007 Location: New Mexico Photos: Albums Posts: 1,125 Original Poster	Originally posted by RonHendriks1966 So you actually have no need at all for an extra lens Or to complete it get next to all those fine lenses the FA85mm/f1.4 just for fun. Ron, My interest in a 50ish lens is to fill the portraiture sweet spot of 75-85mm in terms of 35mm format. I do own a DA 16-50, but I would like a faster, better prime lens for this special purpose. I guess I have a case of LBA, which is not like me, as I have never been much of a gear head. I just like to take pictures and then work the hell out of them in PP. To me, that is the fun part of photography. www.rgoldsteinphotography.com Rob Last edited by robgo2; 02-25-2011 at 10:10 AM.

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02-21-2011, 01:39 PM	#16
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Well it is a wonderfull lens, so getting a good copy is something that you will enjoy for years to come.

02-23-2011, 05:08 PM	#18
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Too bad it didn't work out. The Sigma is only 2mm longer (well and quite a bit fatter in diameter).

02-24-2011, 11:47 AM	#19
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Voightlander Nokton 58mm is also an option if you can find one. Or FA43mm or FA77mm.

02-24-2011, 04:56 PM	#20
robgo2 Veteran Member Join Date: Jan 2007 Location: New Mexico Photos: Albums Posts: 1,125 Original Poster	Originally posted by RonHendriks1966 Voightlander Nokton 58mm is also an option if you can find one. Or FA43mm or FA77mm. The Nokton is manual focus, and the 43 Limited is relatively close in focal length to my 31 Limited and also a bit short for a portrait lens (although certainly not bad.) I already own the 77 Limited. I have decided to give the DA* 55/1.4 one more chance and have ordered one from B&H. I am also giving more consideration to the Sigma 50/1.4, despite its large size and weight. I am really pissed and disappointed that Pentax cannot produce a lens that focuses accurately, especially one that is super fast and not inexpensive. Rob

02-25-2011, 07:57 AM	#21
Egg Salad Veteran Member Join Date: Jul 2009 Location: Berlin, Germany Posts: 344	I'd also recommend the Sigma because it's the closest choice next to the DA* 55. But unfortunately QC is no better than with Pentax, more likely worse. I bought my copy used, so QC was already done by the previous owner who had to get through 3 lenses himself... Quality wise the Nokon is probably the best choice - but well, no AF.

02-25-2011, 09:02 AM	#22
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Originally posted by robgo2 The Nokton is manual focus, and the 43 Limited is relatively close in focal length to my 31 Limited and also a bit short for a portrait lens (although certainly not bad.) I already own the 77 Limited. I have decided to give the DA* 55/1.4 one more chance and have ordered one from B&H. So you actually have no need at all for an extra lens Or to complete it get next to all those fine lenses the FA*85mm/f1.4 just for fun.

02-25-2011, 10:08 AM	#24
robgo2 Veteran Member Join Date: Jan 2007 Location: New Mexico Photos: Albums Posts: 1,125 Original Poster	Originally posted by Egg Salad I'd also recommend the Sigma because it's the closest choice next to the DA* 55. But unfortunately QC is no better than with Pentax, more likely worse. I bought my copy used, so QC was already done by the previous owner who had to get through 3 lenses himself... Quality wise the Nokon is probably the best choice - but well, no AF. If you read the user reviews of the Sigma 50/1.4 (Nikon and Canon mounts) over at B&H, you will find some complaints about focusing accuracy, but overwhelmingly, people love this lens and compare it favorably to anything that Nikon and Canon have to offer. I may ultimately give it a try, but it seems ridiculously large and heavy. Rob

02-25-2011, 11:54 AM	#25
Rondec Loyal Site Supporter Join Date: Mar 2009 Location: Gladys, Virginia Photos: Gallery Posts: 27,653	Originally posted by robgo2 If you read the user reviews of the Sigma 50/1.4 (Nikon and Canon mounts) over at B&H, you will find some complaints about focusing accuracy, but overwhelmingly, people love this lens and compare it favorably to anything that Nikon and Canon have to offer. I may ultimately give it a try, but it seems ridiculously large and heavy. Rob Particularly considering that the DA *55 is also a full frame lens.

02-25-2011, 01:09 PM	#26
Egg Salad Veteran Member Join Date: Jul 2009 Location: Berlin, Germany Posts: 344	I forgot about the focus issues. But I'd file them under poor QC as well. It's not like I had an assistant who carries my stuff for me but I don't care about its size or weight. At all. I don't have it too long yet but from what I already can say is that this lens doesn't create anything you have never seen before. But yeah, it does a very nice job being a great performer. Shaprness/resolution is there - even wide open (at intermediate distances) - the only thing that spoils it are its rather visible CAs. Since no one has mentioned it yet, I'll also add that it focuses considerably faster than the Pentax. The DA* is even said to be clearly slower than the F/FA version (ok, I have to admit that my F 1:1.7 50mm focuses crazily fast - but it's also loud). I haven't seriously compared the F to the new Sigma but if anything then the Sigma isn't much slower. May very likely be just as fast as the F/FA. Also incomprehensible to me is that no one has (ever) metioned the Sigma HSM lenses offer a gear transmission ratio of 1:2. Turning the focus ring for 20° actually moves the distance scale 10°. A thing of genius. Since I saw Sigma has this feature the focusing on my DA* 16-50 totally sucks to me. And the DA* 55 may not be any different. On my Sigma 50, the focus ring moves rather stiff but that's still better than this dead feeling on the 16-50.

02-25-2011, 01:53 PM	#27
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Originally posted by Egg Salad Since no one has mentioned it yet, I'll also add that it focuses considerably faster than the Pentax. The DA* is even said to be clearly slower than the F/FA version This is true, the DA55mm is the slowest of all my lenses in focussing. Since I got the K-5 the difference is even greater because all other lenses gaint speed on the new body. Part of the problem is also a big turn of the focusring. But it can be very good on the spot. Originally posted by robgo2 My interest in a 50ish lens is to fill the portraiture sweet spot of 75-85mm in terms of 35mm format. I do own a DA 16-50, but I would like a faster, better prime lens for this special purpose. I guess I have a case of LBA, which is not like me, as I have never been much of a gear head. I just like to take pictures and then work the hell out of them in PP. To me, that is the fun part of photography. Nice pictures. Then again I would make a break for adding the FA85mm to your lens-line-up since this is also an excellent portraitlens (on the long site). K-7 and FA85mm at f2.0

02-25-2011, 02:29 PM	#28
Egg Salad Veteran Member Join Date: Jul 2009 Location: Berlin, Germany Posts: 344	Being slow doesn't mean it can't be good. But in certain circumstances fast AF just may be critical (most complaints were about focus speed from MFD to infinity which isn't that important in actual use, though). I couldn't find a definite number so can anybody tell me what the actual focus throw is on the DA* 55? On the Sigma it is 90° (+-2°) but for the AF it's just 45° focus throw which makes it so fast. Moving cats are still a challenge it can't win...

02-25-2011, 03:27 PM	#29
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	I think it is some 110-120 degrees. Not messured it.

02-25-2011, 03:44 PM	#30
Egg Salad Veteran Member Join Date: Jul 2009 Location: Berlin, Germany Posts: 344	No wonder it's slower than the Sigma then. Just checked: the F 1:1.7 50mm offers ~160°, the SMC Pentax 1:1.4/50 190-200°. Thanks.