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05-17-2022, 03:48 AM   #121
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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
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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 - 2 Likes   #123
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K-1 | FF-mode | 29.4mm (DFA21Ltd+DA TC1.4x) | ISO100 | f/3.5 | 1/13s
05-21-2022, 12:05 AM - 5 Likes   #124
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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
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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
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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 - 3 Likes   #127
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K-1 | FF mode | 21mm


05-25-2022, 12:56 PM   #128
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K-1 | FF mode | 21mm
05-25-2022, 08:53 PM - 1 Like   #129
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Pentax K1 MKII D-FA21mm f/2.4 ASPH Limited @ f/2.4
05-26-2022, 01:30 AM   #130
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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 - 4 Likes   #131
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That time of year

05-28-2022, 08:34 AM - 6 Likes   #132
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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   #133
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Olympic Park, Munich - Sun, Tree, Roof


K-1 | 21mm

06-15-2022, 04:55 PM - 2 Likes   #134
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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   #135
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K-1 | FF mode | DFA21Ltd. + DA TC1.4x = 29.4mm | f/3.5

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