Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-17-2022, 03:48 AM   #121
Pentaxian




Join Date: May 2015
Photos: Albums
Posts: 3,304
QuoteOriginally posted by ChatMechant Quote
Some interesting flare on this one:
Does it have a maze pattern when you zoom in like 300% into purple area of the raw file? It looks a little bit like the sensor crosstalk that's very common on Fuji amongst others. I've once produced it on my K-3 II with the DA15. UWA lenses can make the rays come at steep angles making the light bleed across sensor "pixels". Light that forms flare can have even more extreme angles as it's coming from outside the normal path.

I see some flare that looks like sensor flare, ie those dotted/striped flares, in your image which makes me suspect it is indeed the sensor purple effect. DSLR's are more resistant to it thanks to the flange distance but it can happen. Seems much more common on milcs though.

So you have UWA making rays come in at low angles to the sensor plane, then you have flare enabling even more extreme angles, this causes light come it at super low angles and reflection off the sensor as well as green pixels being affected by light coming through the adjacent red and blue pixel filters.

A quick internet search gave this article
Why and How Fuji Cameras Produce a Strange Purple Flare/Grid Artifact | PetaPixel

Edit: oh by the way I could make it go away in Rawtherapee by changing the demosaicing algorithm and the Green equiliberation setting. If I'm not mixing things up that is.


Last edited by house; 05-17-2022 at 04:07 AM.
05-17-2022, 06:56 PM - 1 Like   #122
Pentaxian
ChatMechant's Avatar

Join Date: Jun 2010
Location: Matsuyama
Photos: Gallery
Posts: 1,284
Yes, I think I see what you mean, it looks kind of like woven fabric when I zoom into the purple area. Never seen that before. I admit that my processing deliberately emphasized the purple because I thought it looked interesting.





QuoteOriginally posted by house Quote
Does it have a maze pattern when you zoom in like 300% into purple area of the raw file? It looks a little bit like the sensor crosstalk that's very common on Fuji amongst others. I've once produced it on my K-3 II with the DA15. UWA lenses can make the rays come at steep angles making the light bleed across sensor "pixels". Light that forms flare can have even more extreme angles as it's coming from outside the normal path.

I see some flare that looks like sensor flare, ie those dotted/striped flares, in your image which makes me suspect it is indeed the sensor purple effect. DSLR's are more resistant to it thanks to the flange distance but it can happen. Seems much more common on milcs though.

So you have UWA making rays come in at low angles to the sensor plane, then you have flare enabling even more extreme angles, this causes light come it at super low angles and reflection off the sensor as well as green pixels being affected by light coming through the adjacent red and blue pixel filters.

A quick internet search gave this article
Why and How Fuji Cameras Produce a Strange Purple Flare/Grid Artifact | PetaPixel

Edit: oh by the way I could make it go away in Rawtherapee by changing the demosaicing algorithm and the Green equiliberation setting. If I'm not mixing things up that is.
05-19-2022, 11:28 AM - 4 Likes   #123
Site Supporter
Site Supporter
acoufap's Avatar

Join Date: Jan 2011
Location: Munich, Germany
Photos: Gallery | Albums
Posts: 4,159


K-1 | FF-mode | 29.4mm (DFA21Ltd+DA TC1.4x) | ISO100 | f/3.5 | 1/13s
05-21-2022, 12:05 AM - 6 Likes   #124
Site Supporter
Site Supporter
Digitalis's Avatar

Join Date: Mar 2009
Location: Melbourne, Victoria
Photos: Gallery
Posts: 11,694

Pentax K1MKII D-FA21mm f/2.4 ED ASPH Limited @ f/2.4 ISO 100 1/1250th



Pentax K1MKII D-FA21mm f/2.4 ED ASPH Limited @ f/2.4 ISO 100 1/320th


05-21-2022, 10:06 AM - 3 Likes   #125
Pentaxian




Join Date: Nov 2010
Location: Pacific Northwest
Photos: Gallery
Posts: 913
Today I received my new D FA 21mm Ltd in the mail. Some of you may recall my tale of woe, described earlier in this thread, about falling and bending the hood back in February. I sent it to PM2S in France and, for one reason or another, they sent me an entirely new lens. The "repair" cost me 475 Euros and my credit card company covered me. Since they didn't actually repair the original lens I can't comment on their repair quality, but they managed the issue well and I have my lens back. Life is good!
05-21-2022, 02:22 PM   #126
Pentaxian
Paul the Sunman's Avatar

Join Date: Aug 2011
Location: Melbourne
Photos: Gallery
Posts: 4,836
Original Poster
QuoteOriginally posted by nosliwmit Quote
Today I received my new D FA 21mm Ltd in the mail. Some of you may recall my tale of woe, described earlier in this thread, about falling and bending the hood back in February. I sent it to PM2S in France and, for one reason or another, they sent me an entirely new lens. The "repair" cost me 475 Euros and my credit card company covered me. Since they didn't actually repair the original lens I can't comment on their repair quality, but they managed the issue well and I have my lens back. Life is good!
A wonderful result. I am sure you will be very careful with it from now on. I can imagine it being a very useful lens for Irish scenery.

---------- Post added 22-05-22 at 07:29 AM ----------

QuoteOriginally posted by Digitalis Quote
Pentax K1MKII D-FA21mm f/2.4 ED ASPH Limited @ f/2.4 ISO 100 1/1250th



Pentax K1MKII D-FA21mm f/2.4 ED ASPH Limited @ f/2.4 ISO 100 1/320th
Nice one Digitalis. I see you have nailed a particular muted look with this lens that is particularly suited to autumn/winter. The bokeh is just right for it.
05-22-2022, 12:06 PM - 5 Likes   #127
Site Supporter
Site Supporter
acoufap's Avatar

Join Date: Jan 2011
Location: Munich, Germany
Photos: Gallery | Albums
Posts: 4,159
x-post


K-1 | FF mode | 21mm


05-25-2022, 12:56 PM - 1 Like   #128
Site Supporter
Site Supporter
acoufap's Avatar

Join Date: Jan 2011
Location: Munich, Germany
Photos: Gallery | Albums
Posts: 4,159


K-1 | FF mode | 21mm
05-25-2022, 08:53 PM - 2 Likes   #129
Site Supporter
Site Supporter
Digitalis's Avatar

Join Date: Mar 2009
Location: Melbourne, Victoria
Photos: Gallery
Posts: 11,694


Pentax K1 MKII D-FA21mm f/2.4 ASPH Limited @ f/2.4
05-26-2022, 01:30 AM   #130
Site Supporter
Site Supporter
RobA_Oz's Avatar

Join Date: Nov 2008
Location: Tasmania, Australia
Photos: Gallery
Posts: 8,182
QuoteOriginally posted by Digitalis Quote


Pentax K1 MKII D-FA21mm f/2.4 ASPH Limited @ f/2.4
Nice rendering! It looks like it’s floating on the air.
05-26-2022, 01:40 AM - 6 Likes   #131
Pentaxian
Paul the Sunman's Avatar

Join Date: Aug 2011
Location: Melbourne
Photos: Gallery
Posts: 4,836
Original Poster
That time of year

05-28-2022, 08:34 AM - 7 Likes   #132
Pentaxian




Join Date: Nov 2010
Location: Pacific Northwest
Photos: Gallery
Posts: 913
A couple from me, now that I have my lens again:

From a visit to Windmill Lane Studios in Dublin:



On Great Saltee Island:
06-15-2022, 12:18 PM - 1 Like   #133
Site Supporter
Site Supporter
acoufap's Avatar

Join Date: Jan 2011
Location: Munich, Germany
Photos: Gallery | Albums
Posts: 4,159
x-post

Olympic Park, Munich - Sun, Tree, Roof


K-1 | 21mm

06-15-2022, 04:55 PM - 4 Likes   #134
Site Supporter
Site Supporter
Digitalis's Avatar

Join Date: Mar 2009
Location: Melbourne, Victoria
Photos: Gallery
Posts: 11,694
The DFA21 isn't officially supported on the K10D as the mount isn't KAF4, AF works surprisingly well but no aperture control.

The rich colours are a trait of CCD images, with no need to post processing the Bokeh is superbly smooth.



Pentax K10D D-FA21mm f/2.4 @ f/2.4 ISO 400 1/125th
06-19-2022, 12:41 PM - 1 Like   #135
Site Supporter
Site Supporter
acoufap's Avatar

Join Date: Jan 2011
Location: Munich, Germany
Photos: Gallery | Albums
Posts: 4,159

x-post


K-1 | FF mode | DFA21Ltd. + DA TC1.4x = 29.4mm | f/3.5

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!
asph, beach, club, clubs, f/2.4, fa, fa 21mm f/2.4, hood, iso, k-mount, k1mkii, lens, pentax, pentax lens, pentax-d, pentax-d fa 21mm, post, repair, shot, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax-DA 21mm Limited, DA 35mm Macro Limited and Pentax-M 200mm F4 7.62lew Sold Items 4 06-26-2021 09:18 PM
For Sale - Sold: DA Limited 21mm / DA Limited 35mm Macro / DA Limited 70mm top-quark Sold Items 3 04-23-2013 05:01 AM
For Sale - Sold: DA 10-17mm fisheye, 21mm Limited, FA 35mm, FA 50mm, DFA 100mm Macro (Worldwide Albert Siegel Sold Items 8 09-18-2010 06:08 PM



All times are GMT -7. The time now is 02:01 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