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12-15-2018, 04:17 AM   #76
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QuoteOriginally posted by Des Quote
I don't use in-camera NR Dan. DxO does it fine.
Now that raises another question: my understanding is that the software built into the camera actually takes two pictures and goes through a process of "subtracting" one from the other (on the assumption that what's in one but not the other must be noise) and then adding the parts that do belong to compile one relatively noise-free image - but the software in the computer doesn't have that second image, so it must be performing some kind of pixel-by-pixel analysis of the image in order to determine what belongs and what doesn't - and then fills in the "what doesn't" by interpolation. In other words, a "scientific wild-assed guess". So I'm wondering what is it about the resultant images you've taken that persuades you that the software in the computer is best?

QuoteOriginally posted by Des Quote
Nice image, but maybe a little under-exposed. Try 400 ISO - you might be surprised. :-)
Good point - I used to always keep ASA 400 film in my camera because it offered the most flexibility (and I was stingy with film, hated partially exposed rolls having to be swapped out because of changes in lighting conditions). And since there are no silver nitrate granules to cluster up, it makes perfect sense to go for a "faster film" number.

12-15-2018, 06:28 AM - 2 Likes   #77
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QuoteOriginally posted by dlh Quote
Now that raises another question: my understanding is that the software built into the camera actually takes two pictures and goes through a process of "subtracting" one from the other (on the assumption that what's in one but not the other must be noise) and then adding the parts that do belong to compile one relatively noise-free image - but the software in the computer doesn't have that second image, so it must be performing some kind of pixel-by-pixel analysis of the image in order to determine what belongs and what doesn't - and then fills in the "what doesn't" by interpolation. In other words, a "scientific wild-assed guess". So I'm wondering what is it about the resultant images you've taken that persuades you that the software in the computer is best?
That's only for a very specific type of noise that is introduced by long exposures. The technique is called dark frame subtraction and can be done manually by taking one dark frame (at several points during the session for best results) to avoid taking 2x time for every single shot when allowing the camera to do it.

Normal noise reduction Doesn't do this. The processor makes decisions about how to apply nr, which is often better when done with the power of a computer. Time and processing power are more limited on the camera.

DXO prime noise reduction is excellent. (Requires RAW files)
12-15-2018, 02:49 PM - 1 Like   #78
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QuoteOriginally posted by dlh Quote
Now that raises another question: my understanding is that the software built into the camera actually takes two pictures and goes through a process of "subtracting" one from the other (on the assumption that what's in one but not the other must be noise) and then adding the parts that do belong to compile one relatively noise-free image - but the software in the computer doesn't have that second image, so it must be performing some kind of pixel-by-pixel analysis of the image in order to determine what belongs and what doesn't - and then fills in the "what doesn't" by interpolation. In other words, a "scientific wild-assed guess". So I'm wondering what is it about the resultant images you've taken that persuades you that the software in the computer is best?
That sent me looking through the manual and e-book for the K-3, as I'd never heard of it before. I found nothing about it. Thanks to UV for confirming that the in-camera NR doesn't operate by dark-frame subtraction.

As UV says, DxO software does excellent noise reduction, while preserving detail (its feature is called PRIME, available only in the Elite version of PhotoLab or its precursor OpticsPro). You can adjust it manually, but I tend to leave on Auto.
12-31-2018, 10:17 AM - 3 Likes   #79
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D FA 100 Portrait

Portrait use for D FA 100 on K-1ii. I'll be adding this to my bag for portraits. I was really happy with the results it gives in this mode.



01-08-2019, 09:16 PM - 4 Likes   #80
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01-13-2019, 05:05 AM   #81
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02-03-2019, 06:13 AM - 2 Likes   #82
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first real macro shot

I've used the DFA100 for portrait and landscape, but this is my first real experience with macro work. As a whole the set was a little soft due to my lack of experience in the depth of field when in macro mode, but I had fun.

DFA100 on a K-1ii / handlheld yongnuo flash with trigger on camera. Just winter sticker weeds in the yard the flower was about nickel sized.



04-08-2019, 04:42 AM   #83
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flowers are probably about 5-6mm diameter, taken from about six inches.
04-14-2019, 06:00 PM   #84
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kwanzan
05-04-2019, 10:33 AM - 2 Likes   #85
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at f2.8


at f16
05-23-2019, 09:25 AM   #86
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Do you suffer from "reptile dysfunction"?

Young blacksnake, also called "Eastern black racer" - eat everything from crickets to rats. Good luck to have one in your crawlspace.
06-01-2019, 06:11 PM - 4 Likes   #87
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06-02-2019, 06:00 PM   #88
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QuoteOriginally posted by Des Quote
Those are great shots, Des: wings are so clear - almost looks like leaded glass.
06-02-2019, 08:49 PM   #89
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QuoteOriginally posted by K2 to K50 Quote
Those are great shots, Des: wings are so clear - almost looks like leaded glass.
Thanks very much for that. Fill flash helps bring out details like that. As has been said here, the hardest part with insect macro in the field is getting the focus right, because you usually need to shoot handheld and the DOF is very thin, even at narrow apertures.
06-03-2019, 12:32 AM   #90
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QuoteOriginally posted by Des Quote
Thanks very much for that. Fill flash helps bring out details like that. As has been said here, the hardest part with insect macro in the field is getting the focus right, because you usually need to shoot handheld and the DOF is very thin, even at narrow apertures.
Des, do you mind me asking,
1: Did you use any tele-converter or magnifier for those bee (wasp??) shots, or just the 100mm Macro?
and

2: With the 100mm Macro, how close would you have to get to get that kind of shot ( and is what we see here the original, or cropped?)

I am planning, end of June, on a new KP body, and the 55-300 PLM, and either the 16-85mm F3.5-5.6zoom, and/or the 100mm F2.8 Macro, to get some good modern lenses (the bulk of my lens are film-era Pentax M lenses) and am wondering for instance, how close the100mm Macro needs to get compared, say, to my old Pentax M 50mm Macro (which is still doing its job well, subject to how well I use it!!!)

The only working flash I have at the moment is the built-in flash on my K50: probably not that useful for close-ups. Way back in the late 1970s I bought the then very impressive Vivitar "auto-thyristor" 283 Flash with its own (removable) built-in sensor. You could leave the sensor on the camera's hot shoe, and have the flash away from the camera, connected via a cable.
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