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02-10-2020, 06:13 AM - 6 Likes   #1051
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QuoteOriginally posted by biz-engineer Quote
I have pixel peeped these image samples at 400% and corners don't look tack sharp even with the lens stopped down to f8, even at the long end. Damn , I think I'm going to hold on my purchase order until we have more test charts available. From memory I think my DFA*70-200 is sharper in corners. Was the camera / lens 100% at a 90 degre angle with the book shelf? (DoF can have an out of focus effect at the edges of the frame).
Is this a serious comment or are you poking us for reactions again? I have to ask because I'm not always able to tell the difference...

I'd love to see the 70-210 f/4 lens (from any manufacturer) that's tack sharp in the corners at 400% reproduction. This a D FA 3x tele zoom... not a D FA* prime. I understand some folks need want images that are tack sharp across the frame and into the corners, but - with respect - I think you're setting a new bar of expectation and assessment for this class of lens


Last edited by BigMackCam; 02-10-2020 at 06:26 AM.
02-10-2020, 07:08 AM - 4 Likes   #1052
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400% doesn't show the lens's sharpness, only how the scaling/interpolation algorithm behaves.
02-10-2020, 07:09 AM - 10 Likes   #1053
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QuoteOriginally posted by biz-engineer Quote
I have pixel peeped these image samples at 400% and corners don't look tack sharp even with the lens stopped down to f8, even at the long end. Damn , I think I'm going to hold on my purchase order until we have more test charts available. From memory I think my DFA*70-200 is sharper in corners. Was the camera / lens 100% at a 90 degre angle with the book shelf? (DoF can have an out of focus effect at the edges of the frame).
You have to go deeper. 400% is for amateurs
Everyone knows pixel peeping only starts at 500%
02-10-2020, 07:22 AM   #1054
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QuoteOriginally posted by biz-engineer Quote
I have pixel peeped these image samples at 400% and corners don't look tack sharp even with the lens stopped down to f8, even at the long end. Damn , I think I'm going to hold on my purchase order until we have more test charts available. From memory I think my DFA*70-200 is sharper in corners. Was the camera / lens 100% at a 90 degre angle with the book shelf? (DoF can have an out of focus effect at the edges of the frame).
Good chance that image quality is excellent on this lens as most recent lenses are. But I'm pretty confident that it won't be perfectly sharp across the entire frame – although I wish it would. It seems to be positioned as a smaller and lighter alternative to the 2.8 version which usually comes with a trade off in optical performance. The question is how much.

02-10-2020, 07:23 AM - 2 Likes   #1055
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QuoteOriginally posted by mee Quote
Still seeing a little fringing in the snow, as one might with the Tamron variant, but its minor and likely easily correctable in post. Extreme case however.



What is that place? It looks like a public farm of some sorts on Google Maps.
Tess and I have often seen purple fringing out in nature looking with just our eyes. I could show you magazine images with purple fringing. "Purple fringing is always bad and always needs correction " people seem to me to be kind of a cult. Sometimes, it's part of nature. It has to be really bad, before I bother correcting it.

---------- Post added 02-10-20 at 09:31 AM ----------


QuoteOriginally posted by Mistral75 Quote
400% doesn't show the lens's sharpness, only how the scaling/interpolation algorithm behaves.
Exactly.... and it's also really hard to tell if an image is sharp on a 200 plus DPI monitor. At 109 DPI, on my old 2010 iMac 27 inch display, at 100% you can clearly see the level of sharpness.
Even though I have a 4k display for my laptop, I still find the 10 year old tech better for evaluating images at 1:1.

IMHO evaluating at 400% is a waste of time, although it is conceivable that if you did all your evaluation at 400% you could learn to see the differences. But I'd put the odds of that being true at maybe 50/50, do you feel lucky?

I used to have a demo of upscaled images, showing that good upscaling software actually cleans up messy details in the photo, making it look artificially crisp, but that may look better to you. I had a test chart printed on an inkjet printer that had some fuzzy places with what looked like ink splatter. Upscaling then downsizing cleaned them right up.

The upscaled image looked better, but it wasn't an accurate reproduction of what was there. This being just one of the reasons I feel most sharpness comparisons are overrated. Tack sharp doesn't always produce the most pleasing results. I don't know if it's just the photographers not understanding how to get the most out of a lens, but most of the examples I've seen of ridiculously sharp Zeiss lenses, have not been pleasing images. I'm not sure if that's because sharp images are less than pleasing, or people who own them are crappy photographers. IN the case of the the DFA*50 1.4 and the comparable Zeiss, I'd take the Pentax straight up, even if they were the same price.

If you want to get serious about all this stuff, you can kill a lot of time for not much better results.

Last edited by normhead; 02-10-2020 at 08:18 AM.
02-10-2020, 11:46 AM - 2 Likes   #1056
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QuoteOriginally posted by ZeljkoS Quote
You have to go deeper. 400% is for amateursEveryone knows pixel peeping only starts at 500%
I agree

---------- Post added 10-02-20 at 19:50 ----------

QuoteOriginally posted by normhead Quote
people seem to me to be kind of a cult. Sometimes, it's part of nature. It has to be really bad, before I bother correcting it.
It's like vignetting. I enjoyed the vignetting effect of b&w vintage shots forcing the eyes attention onto the subject. Now I have to add some vignetting on digital images because the new digital lenses don't produce much vignetting anymore.
02-10-2020, 12:21 PM - 9 Likes   #1057
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Well kids, it's no longer a rumour. I got an email from my pusher today.
My lens is waiting for me. I will be picking it up tomorrow.

02-10-2020, 12:23 PM - 2 Likes   #1058
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QuoteOriginally posted by normhead Quote
Tess and I have often seen purple fringing out in nature looking with just our eyes.
Isn't purple fringing supposed to be a digital sensor only aberration? Are you telling us your are a robot normhead 🤔

Lot's of people love the bubbly helios or vignetting etc. but I've never heard of purple fringe lovers. Perhaps lensbaby pf is coming next. I somehow doubt it.

Read this fairly interesting article about creating film looks for digital movies.
Knives Out, Last Jedi DP has a plan to end the film-vs-digital debate - Polygon
It does mention halation which can I guess be compared to pf. Purple fringing however is a sort of eighties neon version of halation. Removed purple fringing does leave a halation like halo around edges.

Fringing seems to be the class of aberration pentax is least likely to correct. Perhaps because it adds a filmic look?
02-10-2020, 12:32 PM   #1059
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QuoteOriginally posted by Wheatfield Quote
Well kids, it's no longer a rumour. I got an email from my pusher today.
My lens is waiting for me. I will be picking it up tomorrow.
Enjoy!!
02-10-2020, 12:35 PM - 1 Like   #1060
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Pf is the one abberation I get rid of everytime I encounter it (which is a lot with my FA77). I do not like the look of skin with purple fringing.
On a very snowy scenery it may not bother me that much, but if the hands of my model look like she is holding the holy spirit itself, no thanks.
02-10-2020, 01:36 PM - 1 Like   #1061
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QuoteOriginally posted by house Quote
Isn't purple fringing supposed to be a digital sensor only aberration? Are you telling us your are a robot normhead 🤔

Lot's of people love the bubbly helios or vignetting etc. but I've never heard of purple fringe lovers. Perhaps lensbaby pf is coming next. I somehow doubt it.

Read this fairly interesting article about creating film looks for digital movies.
Knives Out, Last Jedi DP has a plan to end the film-vs-digital debate - Polygon
It does mention halation which can I guess be compared to pf. Purple fringing however is a sort of eighties neon version of halation. Removed purple fringing does leave a halation like halo around edges.

Fringing seems to be the class of aberration pentax is least likely to correct. Perhaps because it adds a filmic look?
QuoteOriginally posted by WorksAsIntended Quote
Pf is the one abberation I get rid of everytime I encounter it (which is a lot with my FA77). I do not like the look of skin with purple fringing.
On a very snowy scenery it may not bother me that much, but if the hands of my model look like she is holding the holy spirit itself, no thanks.
The full size image @mattt posted has the tiniest amount of fringing along the very edge of the snow - and I do mean the tiniest. It's an extreme situation - many a modern lens will show this or considerably worse. If this is how the 70-210 f/4 performs in an extreme situation, I don't think we've much to worry about...
02-10-2020, 01:41 PM   #1062
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QuoteOriginally posted by BigMackCam Quote
The full size image @mattt posted has the tiniest amount of fringing along the very edge of the snow - and I do mean the tiniest. It's an extreme situation - many a modern lens will show this or considerably worse. If this is how the 70-210 f/4 performs in an extreme situation, I don't think we've much to worry about...
I did not see a proplem with pf on that lense. Iven if there were a lot of pf, it is easiely adjusted in postprocessing. Just the general idea posted in this threat, that pf is part of the image is nothing I can relate to. That's all.
02-10-2020, 01:51 PM - 2 Likes   #1063
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QuoteOriginally posted by mattt Quote
Here's a private album..... --> Right Here <--
Maaan, I have a 4K monitor and this DFA 70-210mm on K-1 is badass!
02-10-2020, 04:28 PM   #1064
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QuoteOriginally posted by BigMackCam Quote
The full size image @mattt posted has the tiniest amount of fringing along the very edge of the snow - and I do mean the tiniest. It's an extreme situation - many a modern lens will show this or considerably worse. If this is how the 70-210 f/4 performs in an extreme situation, I don't think we've much to worry about...

I wasn't commenting on the performance of the lens.
02-10-2020, 06:20 PM   #1065
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QuoteOriginally posted by house Quote
Isn't purple fringing supposed to be a digital sensor only aberration? Are you telling us your are a robot normhead ��

Lot's of people love the bubbly helios or vignetting etc. but I've never heard of purple fringe lovers. Perhaps lensbaby pf is coming next. I somehow doubt it.

Read this fairly interesting article about creating film looks for digital movies.
Knives Out, Last Jedi DP has a plan to end the film-vs-digital debate - Polygon
It does mention halation which can I guess be compared to pf. Purple fringing however is a sort of eighties neon version of halation. Removed purple fringing does leave a halation like halo around edges.

Fringing seems to be the class of aberration pentax is least likely to correct. Perhaps because it adds a filmic look?
I've only seen CA's with reading glasses that are using a higher index plastic and/or don't have decent coatings (beyond photography gear). This but only at largely side angles due to the design of lenses in glasses. I've never seen CA or any type of color fringing with my bare eyes. I didn't even think it was possible for human eyes to be affected!

Last edited by mee; 02-10-2020 at 06:31 PM.
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