Win a Pentax Limited Lens: Raffle Now Live!

timo · 04-19-2010, 08:34 AM

Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here.

The impression I got before mine was pinched was that f/1.2 was perfectly useable if I got the focus spot-on, and that's a big if. Stop down one click and the contrast in the detail improved dramatically - a bit like the f/1.4 in that respect. It wasn't so much that f/1.2 was soft, more that with high contrast edges the white would bleed into adjacent dark areas with a kind of glow. The trick was to avoid high-contrast highlights. My K105 f/2.8 is very similar wide open in that respect, and both lens suffer a bit from longitudinal CA with highlights (red in front of, green behind, the plane of focus). It was a great lens though.

Tim

photogerald · 04-19-2010, 10:16 PM

Originally posted by rparmar

That could be, but I'm not likely to get it any more in focus. I do think it is down to the subject. Being a print of a woodcut, this has highly contrasting lines placed closely together. It is probably a worst-case scenario. Some subjects show this aberration more than others. See the cat photo where it is just not a problem!

The K55/1.8 is a lens I would love to have to compare with this.

Since timo mentioned that this lens suffers from some longitudinal CA (many ultra-fast lenses have this problem), the purple edges could just indicate that your shot was very slightly back-focused.

Anyways, thanks for the detailed writeup of this interesting lens.

**rparmar** · 04-20-2010, 07:15 AM

Originally posted by timo

The impression I got before mine was pinched was that f/1.2 was perfectly useable if I got the focus spot-on, and that's a big if. Stop down one click and the contrast in the detail improved dramatically - a bit like the f/1.4 in that respect. It wasn't so much that f/1.2 was soft, more that with high contrast edges the white would bleed into adjacent dark areas with a kind of glow. The trick was to avoid high-contrast highlights.

Tim, that is an exact description of my experience. Well said!

Originally posted by photogerald

Since timo mentioned that this lens suffers from some longitudinal CA (many ultra-fast lenses have this problem), the purple edges could just indicate that your shot was very slightly back-focused.

I shot several and took the crispest one. But yes, this could still be a case of operator error.

Originally posted by Jimfear

I'll contribute with another real world example, plus a crop for the pixel-peepers.

Thanks everyone for their contributions. This sort of thread would have helped me in my purchase decision. I do hope it helps others.

axl · 04-22-2010, 05:19 AM

Here is one street shot at f1.2:

Nass · 10-29-2010, 03:29 PM

I'm just about to have delivery of one of these. It should be a fun exercise to work with it.

yeatzee · 10-29-2010, 04:47 PM

Im with axl, mine shows absolutely zero PF..... it has a bit of red fringing but thats about it. I've actually been EXTREMELY impressed by how little fringing it displays for being F/1.2

axl · 10-30-2010, 12:16 AM

can't wait for my to be fixed.... Really miss this lens.. I've tried 43/77 combo on my holiday as a replacement but it doesn't work... I might even be selling those two in favor of 50/1.2

yeatzee · 10-30-2010, 12:21 AM

Originally posted by axl

can't wait for my to be fixed.... Really miss this lens.. I've tried 43/77 combo on my holiday as a replacement but it doesn't work... I might even be selling those two in favor of 50/1.2

And I remember not long ago you just about to sell it.... and I told you not to

axl · 10-30-2010, 12:36 AM

Originally posted by yeatzee

And I remember not long ago you just about to sell it.... and I told you not to

as much as I don't like to admit it: YOU WERE RIGHT

by now I think, it's optically the best lens I've shot! It kills 43 and pairs nicely with 31....77? I just don't use it so much...

yeatzee · 10-30-2010, 01:29 AM

Originally posted by axl

as much as I don't like to admit it: YOU WERE RIGHTby now I think, it's optically the best lens I've shot! It kills 43 and pairs nicely with 31....77? I just don't use it so much...

Oh how I love that

**rparmar** · 10-31-2010, 12:25 PM

I have now sold my K50/1.2 with some regret. Financial pressures. For me keeping FA43/77 combo makes more sense, since they are smaller and cover a wider focal range.

On the upside, Robbie from this forum now has a lovely new toy to play with!

axl · 10-31-2010, 12:39 PM

funny enough Robin, I've been thinking of doing exactly the opposite way! For me it's all about OOF. And 50/1.2 just blows 43 off the water. It matches perfectly with 31. 77 fit's the line up but it's tad too long for me.... I'll see...

Fl_Gulfer · 10-31-2010, 12:44 PM

But over $600 on fleabay for a A 50 1.2, I think I would rather spend that on a new F-DA 100 2.8 WR.

Fl_Gulfer · 10-31-2010, 12:48 PM

How about a Brand New one.
Brand New Pentax smc A 50mm F1.2 Lens MF K-7 LX MX MZ - eBay (item 180570083156 end time Nov-02-10 19:20:22 PDT)

axl · 10-31-2010, 01:40 PM

Originally posted by Fl_Gulfer

But over $600 on fleabay for a A 50 1.2, I think I would rather spend that on a new F-DA 100 2.8 WR.

I think you are kidding here...
Have you shot K or A 50/1.2?
Even the MF K series destroys anything (and I mean ANYTHING) in it's way IQ wise!!!
But then again I think it's about priorities, if you need WR 100 ish lens than fine...

04-22-2010, 05:19 AM	#19
axl Veteran Member Join Date: Mar 2007 Location: Nove Zamky, Slovakia Photos: Gallery \| Albums Posts: 7,183	real life shot at f1.2 Here is one street shot at f1.2:

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
The real world difference f/1.4 -vs- f/2	Oscar1	Pentax SLR Lens Discussion	13	02-06-2010 10:33 PM
Some K-7 Real World images	yakiniku	Pentax DSLR Discussion	12	08-02-2009 09:13 PM
Snowflakes in the real world	MightyMike	Post Your Photos!	6	12-23-2008 06:40 AM
CA in the DA*16-50 vs Tamron 28-75 in real world	123K10D	Pentax SLR Lens Discussion	10	02-23-2008 02:44 PM
Real world use.	Rob.K	Pentax DSLR Discussion	29	02-12-2007 01:26 PM

04-19-2010, 08:34 AM	#16
timo Veteran Member Join Date: Nov 2006 Location: former Arsenal football stadium Photos: Gallery Posts: 431	Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here. The impression I got before mine was pinched was that f/1.2 was perfectly useable if I got the focus spot-on, and that's a big if. Stop down one click and the contrast in the detail improved dramatically - a bit like the f/1.4 in that respect. It wasn't so much that f/1.2 was soft, more that with high contrast edges the white would bleed into adjacent dark areas with a kind of glow. The trick was to avoid high-contrast highlights. My K105 f/2.8 is very similar wide open in that respect, and both lens suffer a bit from longitudinal CA with highlights (red in front of, green behind, the plane of focus). It was a great lens though. Tim

04-19-2010, 10:16 PM	#17
photogerald Senior Member Join Date: Sep 2009 Posts: 253	Originally posted by rparmar That could be, but I'm not likely to get it any more in focus. I do think it is down to the subject. Being a print of a woodcut, this has highly contrasting lines placed closely together. It is probably a worst-case scenario. Some subjects show this aberration more than others. See the cat photo where it is just not a problem! The K55/1.8 is a lens I would love to have to compare with this. Since timo mentioned that this lens suffers from some longitudinal CA (many ultra-fast lenses have this problem), the purple edges could just indicate that your shot was very slightly back-focused. Anyways, thanks for the detailed writeup of this interesting lens.

04-20-2010, 07:15 AM	#18
rparmar Site Supporter Join Date: Jan 2008 Photos: Gallery Posts: 8,823 Original Poster	Originally posted by timo The impression I got before mine was pinched was that f/1.2 was perfectly useable if I got the focus spot-on, and that's a big if. Stop down one click and the contrast in the detail improved dramatically - a bit like the f/1.4 in that respect. It wasn't so much that f/1.2 was soft, more that with high contrast edges the white would bleed into adjacent dark areas with a kind of glow. The trick was to avoid high-contrast highlights. Tim, that is an exact description of my experience. Well said! Originally posted by photogerald Since timo mentioned that this lens suffers from some longitudinal CA (many ultra-fast lenses have this problem), the purple edges could just indicate that your shot was very slightly back-focused. I shot several and took the crispest one. But yes, this could still be a case of operator error. Originally posted by Jimfear I'll contribute with another real world example, plus a crop for the pixel-peepers. Thanks everyone for their contributions. This sort of thread would have helped me in my purchase decision. I do hope it helps others.

10-29-2010, 03:29 PM	#20
Nass Veteran Member Join Date: Aug 2009 Location: The British Isles Photos: Gallery Posts: 2,402	I'm just about to have delivery of one of these. It should be a fun exercise to work with it.

10-29-2010, 04:47 PM	#21
yeatzee Veteran Member Join Date: Feb 2009 Location: Temecula Photos: Gallery \| Albums Posts: 3,675	Im with axl, mine shows absolutely zero PF..... it has a bit of red fringing but thats about it. I've actually been EXTREMELY impressed by how little fringing it displays for being F/1.2

10-30-2010, 12:16 AM	#22
axl Veteran Member Join Date: Mar 2007 Location: Nove Zamky, Slovakia Photos: Gallery \| Albums Posts: 7,183	can't wait for my to be fixed.... Really miss this lens.. I've tried 43/77 combo on my holiday as a replacement but it doesn't work... I might even be selling those two in favor of 50/1.2

10-30-2010, 12:21 AM	#23
yeatzee Veteran Member Join Date: Feb 2009 Location: Temecula Photos: Gallery \| Albums Posts: 3,675	Originally posted by axl can't wait for my to be fixed.... Really miss this lens.. I've tried 43/77 combo on my holiday as a replacement but it doesn't work... I might even be selling those two in favor of 50/1.2 And I remember not long ago you just about to sell it.... and I told you not to

10-30-2010, 12:36 AM	#24
axl Veteran Member Join Date: Mar 2007 Location: Nove Zamky, Slovakia Photos: Gallery \| Albums Posts: 7,183	Originally posted by yeatzee And I remember not long ago you just about to sell it.... and I told you not to as much as I don't like to admit it: YOU WERE RIGHT by now I think, it's optically the best lens I've shot! It kills 43 and pairs nicely with 31....77? I just don't use it so much...

10-30-2010, 01:29 AM	#25
yeatzee Veteran Member Join Date: Feb 2009 Location: Temecula Photos: Gallery \| Albums Posts: 3,675	Originally posted by axl as much as I don't like to admit it: YOU WERE RIGHTby now I think, it's optically the best lens I've shot! It kills 43 and pairs nicely with 31....77? I just don't use it so much... Oh how I love that

10-31-2010, 12:25 PM	#26
rparmar Site Supporter Join Date: Jan 2008 Photos: Gallery Posts: 8,823 Original Poster	I have now sold my K50/1.2 with some regret. Financial pressures. For me keeping FA43/77 combo makes more sense, since they are smaller and cover a wider focal range. On the upside, Robbie from this forum now has a lovely new toy to play with!

10-31-2010, 12:39 PM	#27
axl Veteran Member Join Date: Mar 2007 Location: Nove Zamky, Slovakia Photos: Gallery \| Albums Posts: 7,183	funny enough Robin, I've been thinking of doing exactly the opposite way! For me it's all about OOF. And 50/1.2 just blows 43 off the water. It matches perfectly with 31. 77 fit's the line up but it's tad too long for me.... I'll see...

10-31-2010, 12:44 PM	#28
Fl_Gulfer Veteran Member Join Date: Jul 2007 Location: Florida Gulfer Photos: Albums Posts: 3,054	But over $600 on fleabay for a A 50 1.2, I think I would rather spend that on a new F-DA 100 2.8 WR.

10-31-2010, 12:48 PM	#29
Fl_Gulfer Veteran Member Join Date: Jul 2007 Location: Florida Gulfer Photos: Albums Posts: 3,054	How about a Brand New one. Brand New Pentax smc A 50mm F1.2 Lens MF K-7 LX MX MZ - eBay (item 180570083156 end time Nov-02-10 19:20:22 PDT)

10-31-2010, 01:40 PM	#30
axl Veteran Member Join Date: Mar 2007 Location: Nove Zamky, Slovakia Photos: Gallery \| Albums Posts: 7,183	Originally posted by Fl_Gulfer But over $600 on fleabay for a A 50 1.2, I think I would rather spend that on a new F-DA 100 2.8 WR. I think you are kidding here... Have you shot K or A 50/1.2? Even the MF K series destroys anything (and I mean ANYTHING) in it's way IQ wise!!! But then again I think it's about priorities, if you need WR 100 ish lens than fine...

Real World Tests of the SMC K 50 f/1.2

Win a Pentax Limited Lens: Raffle Now Live!