Lightnings taking a ride

by ceinmart

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756 reputation
46
bio website marksblog.com
location Minnesota
age
visits member for 5 years, 1 month
seen 2 days ago
I've been a software developer for a lot longer than I'm willing to admit. My current interests are C++ and Python on Windows, but I've been known to dabble in Linux and I try to be language agnostic when I can.

2d
comment Is the anti alias filter really a blurring filter?
@joojaa the answer is complex. As noted by this answer, only half of the problem is the anti-aliasing filter, the other is the Bayer filter demosaicing. The anti-alias will send some of the information that should have gone into one color pixel into a different color pixel instead. Modern demosaic filters are not simple beasts, and I doubt their response can be modeled consistently.
2d
comment Is the anti alias filter really a blurring filter?
@RogerKrueger you can theoretically get full resolution if the input is monochrome, the output doesn't matter. I think many modern de-Bayering filters attempt to approach this ideal, but I don't know how close they come.
Apr
27
comment How can I compare 'super-zoom' lenses to make up my mind which one I should buy?
Beware that there are different aspects to image quality, there's no easy way to rank lenses unequivocally. And there are other things to consider, such as speed (F-stops), range, and close focus abilities.
Jan
19
comment What is the 'Golden Ratio' and why is it better than the 'Rule of Thirds?'
@Julian 1/1.61 is approximately 0.62, which is the proportion given in the answer.
Jan
19
comment Does the right calibration temperature for my monitor depend on season?
The appropriate white point is based on the color of the light in the room where you'll be viewing the picture, not on any conditions where the picture was taken.
Jan
19
comment Does the right calibration temperature for my monitor depend on season?
@mattdm there's no seasonal effect. The time of day might matter, but not the time of year.
Jan
19
comment How do I fix a dog's wrong colored eyes in flash photos?
Older versions of Paint Shop Pro were unique in having red-eye removal that works on pet eyes.
Jan
19
comment Should I be shooting in RAW even though I'm a beginner that doesn't know how to retouch photos yet?
@Designer023 thinking before each shot does give you better outcomes, but only if you have enough experience to do the right kind of thinking. See the story at the beginning of blog.codinghorror.com/quantity-always-trumps-quality
Oct
14
comment Should I use JPG or TIFF for high-quality prints?
Your sample link didn't work for me. And is the damage you see in JPEG caused by artifacts, or is it just due to being an 8-bit format?
Aug
30
comment What are the best peak-fall landscape photography locations in the US?
Don't forget the polarizing filter.
Apr
11
comment What happened to Foveon sensors?
@Kendall, just to be clear I'm using the term "pixel" here to represent the smallest addressable area on the image plane. I believe this is the definition from the dawn of digital imaging. The definition is independent of the color information available at each address. I hadn't realized the SD-1 was competitive in pixel addressing, I'd love to see the output.
Apr
11
comment What happened to Foveon sensors?
@Kendall, although each pixel of a Bayer array has a filter in front of it, they are still individual pixels with their own spatial characteristics. Sophisticated interpolation allows the red channel to incorporate information from the green and blue channels as well.
Apr
9
comment What happened to Foveon sensors?
Early Sigma cameras used JPEG compression settings (subsampling) that didn't show their sensor to the best advantage, but they fixed this. I wish I could remember where I had seen a quite graphic demonstration of the problem.
Apr
8
comment How do I get a photo of the required 300dpi or for a 24x36" vinyl banner?
The resolution field is intended for devices which have an actual physical resolution, such as scanners. The EXIF 2.2 spec is at exif.org/Exif2-2.PDF, have a look at page 19 (which is page 25 of the PDF).
Apr
8
comment How do I get a photo of the required 300dpi or for a 24x36" vinyl banner?
The value of 72 is actually mandated by the EXIF standard. Who lets you change it?
Mar
25
comment How do camera body motors compare to in-lens motors for focusing?
Can't agree with the assertion that an in-body motor means all lenses work at the same speed. Don't know if it's due to gearing or what, but some lenses are faster than others even within the same category.
Mar
20
comment What is the difference between the two Pentax 50-200mm DA lenses?
@mattdm, it's understandable that the factory would be stuck with old stock when a better version came out at the same price. I'd guess they're forced by contractual obligation to offer them at list price.
Feb
11
comment How is the YCbCr color space represented in a JPEG image?
Sorry, I didn't mean to imply that the subsampling causes the artifacts. It's just that the existing errors from quantization get blown up 2X, making them much more visible. I think it's important to know that the visible effect of subsampling is more than just a little added fuzziness.
Feb
8
comment How is the YCbCr color space represented in a JPEG image?
Chroma-subsampling doesn't just result in "loss of resolution". It introduces very noticeable artifacts especially in the red channel.
Feb
8
comment How is the YCbCr color space represented in a JPEG image?
@thomasrutter, Photoshop picks the subsampling based on the quality setting you choose. It's not an independent option.