Lee Jay

Lives in United States CO, United States
Works as a Electrical Engineer / Wind Energy Research
Joined on Oct 17, 2003

Comments

Total: 865, showing: 21 – 40
« First‹ Previous12345Next ›Last »
In reply to:

Old Cameras: This is why we can't have nice things.
A drone could damage or take down a plane, its deadly dangerous. All so some jackass with no respect for rules can put pretty pictures in his website. Throw him in jail, fine him heavily and crush his toys. Fire fighting is dangerous and dam expensive.

"Best I can tell you think it is ok to damage an airplane long as it doesn't fall out of the sky."

More reading comprehension problems? I was answering one thing - the OP's statement that "A drone could damage or take down a plane, its deadly dangerous". The "damage" part is true, the rest is such a low possibility that it can be safely ignored.

Got it now? I'll spell it out - a consumer multi-rotor is not "deadly dangerous" to a full-scale airplane. It's possible but highly improbable that a collision will occur, and if one does occur, it's again highly improbable that anyone would be hurt.

In many decades of millions of model-aircraft flights per year, how many humans in full-scale airplanes have been killed by a model aircraft? Answer: ZERO.

The one collision I know of was a worst case - a small, wooden home-built struck in the worst place (wing root leading edge) by the engine of a 50 pound model aircraft. Plane landed safely, no one hurt.

Link | Posted on Jul 5, 2017 at 22:17 UTC
In reply to:

Old Cameras: This is why we can't have nice things.
A drone could damage or take down a plane, its deadly dangerous. All so some jackass with no respect for rules can put pretty pictures in his website. Throw him in jail, fine him heavily and crush his toys. Fire fighting is dangerous and dam expensive.

If a C-130 can be taken down by one bird, then it's way, way too fragile to fly into thunderstorms where it might encounter hail, and at far higher speed than when near the ground. But they use C-130J's for hurricane hunters and hurricanes are the most powerful thunderstorms.

I've seen 172's get a bird right through the windshield and land safely. These things are not a significant safety-of-flight risk. There are over 600 bird strikes just on commercial aircraft every year just in the US. How many single-bird strikes cause a human fatality? If it's not zero, I'd like to hear about it.

Link | Posted on Jul 5, 2017 at 21:30 UTC
In reply to:

Old Cameras: This is why we can't have nice things.
A drone could damage or take down a plane, its deadly dangerous. All so some jackass with no respect for rules can put pretty pictures in his website. Throw him in jail, fine him heavily and crush his toys. Fire fighting is dangerous and dam expensive.

People here seem to be unable to read or something.

The OP of this comment said, "A drone could damage or take down a plane, its deadly dangerous" the second 2/3 of which is simply false. That's all I answered. And I did say, "no one should violate a TFR and everyone flying R/C aircraft of any type should be reading their local applicable NOTAMs" so there's no cause for comments about following the rules.

Further:

A modern jet engine is designed to take a bird strike from a large bird without losing more than 50% of its thrust at any time over the next 14 minutes.

A duck is exceptionally unlikely to bring down a commercial plane all by itself.

Flight 1549 didn't hit a bird, it hit an entire flock of Canadian Geese, which are large birds. This is not relevant to a single consumer multi-rotor.

Link | Posted on Jul 5, 2017 at 21:20 UTC
In reply to:

Old Cameras: This is why we can't have nice things.
A drone could damage or take down a plane, its deadly dangerous. All so some jackass with no respect for rules can put pretty pictures in his website. Throw him in jail, fine him heavily and crush his toys. Fire fighting is dangerous and dam expensive.

I didn't say they wouldn't cause damage - they will. I just said they wouldn't take them down. And 10-20 pound ones won't either, they'll just cause more damage.

Again, the risk of downing a full-scale aircraft with consumer multi-rotor aircraft is exceptionally over-blown, but that doesn't mean operators should violate TFRs. If a TFR is in place, don't fly there, period.

Link | Posted on Jul 5, 2017 at 19:38 UTC
In reply to:

Old Cameras: This is why we can't have nice things.
A drone could damage or take down a plane, its deadly dangerous. All so some jackass with no respect for rules can put pretty pictures in his website. Throw him in jail, fine him heavily and crush his toys. Fire fighting is dangerous and dam expensive.

The chances of a small consumer multi-rotor bringing down a full-scale airplane are minuscule. If full-scale aircraft were that fragile, birds and hail, both of which are struck by full-scale aircraft every day, would be bringing them down by the hundreds. But they aren't.

Still, no one should violate a TFR and everyone flying R/C aircraft of any type should be reading their local applicable NOTAMs.

Link | Posted on Jul 5, 2017 at 19:15 UTC
In reply to:

Lee Jay: Your travel usage couldn't be more different than mine.

First of all, hauling USB chargers is, for me, a much bigger hassle than hauling camera battery chargers. This is because they are slow, you need a lot of them for a lot of devices, and it's hard to charge while you are using the device.

Second, hauling a dSLR and full lens kit has never been a problem for me. I've done it since I was a little kid and don't see any reason to stop. I've only left it in the hotel room when on the way to the hotel pool. Walking 10-16 miles a day with a 10+ pound kit is no problem at all.

Finally, I need focal length range. A fixed 35mm-equivalent lens on travel would be so restrictive to me that I wouldn't bother bringing the camera. I travel with 180° horizontal fisheye through 640mm equivalent, and use most of that range very frequently.

Really?

The article says, "You never know what you're going to end up shooting, when traveling."

That's the exact reason I need focal length range and low-light performance, and exactly the reason I carry a bunch of gear.

Link | Posted on Jun 28, 2017 at 19:45 UTC

Your travel usage couldn't be more different than mine.

First of all, hauling USB chargers is, for me, a much bigger hassle than hauling camera battery chargers. This is because they are slow, you need a lot of them for a lot of devices, and it's hard to charge while you are using the device.

Second, hauling a dSLR and full lens kit has never been a problem for me. I've done it since I was a little kid and don't see any reason to stop. I've only left it in the hotel room when on the way to the hotel pool. Walking 10-16 miles a day with a 10+ pound kit is no problem at all.

Finally, I need focal length range. A fixed 35mm-equivalent lens on travel would be so restrictive to me that I wouldn't bother bringing the camera. I travel with 180° horizontal fisheye through 640mm equivalent, and use most of that range very frequently.

Link | Posted on Jun 28, 2017 at 14:03 UTC as 61st comment | 3 replies
On article Video: a quick introduction to panning photography (17 comments in total)
In reply to:

Lee Jay: I got sick of watching him because he looks like he's had a gallon of coffee, but did he really not make any mention of ND filter use in this type of photography?

It's common for me to choose a shutter speed which requires more than f/22 at ISO 100 (and so did the guy in the video - 1/10th at ISO 100 requires f/45 in bright sunlight). It's also common for me to want both shallow DOF and panning blur at the same time. As such, it's common for me to use a 3 or 4 stop ND filter for this type of shooting.

Link | Posted on Jun 17, 2017 at 01:26 UTC
On article Video: a quick introduction to panning photography (17 comments in total)

I got sick of watching him because he looks like he's had a gallon of coffee, but did he really not make any mention of ND filter use in this type of photography?

Link | Posted on Jun 16, 2017 at 13:31 UTC as 7th comment | 2 replies
On article First pictures from the new Nikon 8-15mm fisheye (139 comments in total)
In reply to:

quietrich: "on the (mistaken) assumption that they will always create unnaturally distorted images"
'Distortion' surely refers to scale and perspective, as well as lines. Ultra-wide and fisheyes will always result in distorted images, distortion which we might or might not like; but it is unavoidably there.

virtualreality - the world is spherical from the point of view of the camera aperture. This is utterly obvious. The camera aperture is a small point and the world is all around it.

Link | Posted on Jun 14, 2017 at 16:16 UTC
On article First pictures from the new Nikon 8-15mm fisheye (139 comments in total)
In reply to:

quietrich: "on the (mistaken) assumption that they will always create unnaturally distorted images"
'Distortion' surely refers to scale and perspective, as well as lines. Ultra-wide and fisheyes will always result in distorted images, distortion which we might or might not like; but it is unavoidably there.

And you're wrong, since rectilinear lenses have exactly the same problem (mapping a spherical world onto a flat plane). And as I already said, at least for me, most of the time rectilinear distortion is *worse* on ultrawides. To put it another way, when I got my fisheye, I nearly stopped using my rectilinear ultrawide.

Toselli above said it right - those 180 degree IMAX domes use a fisheye lens with the image projected onto the inside of a half-sphere. That's really the only way to do imagery without distortion.

Link | Posted on Jun 14, 2017 at 15:16 UTC
On article First pictures from the new Nikon 8-15mm fisheye (139 comments in total)
In reply to:

quietrich: "on the (mistaken) assumption that they will always create unnaturally distorted images"
'Distortion' surely refers to scale and perspective, as well as lines. Ultra-wide and fisheyes will always result in distorted images, distortion which we might or might not like; but it is unavoidably there.

From the point of view of the lens aperture, which is small relative to the world, the world is spherical. The aperture is a point looking around from the center of the sphere (let's ignore macro and telecentricity for this discussion). The mapping of that spherical world onto the flat plane of the sensor or film (called "projection") is the same problem as trying to map the spherical globe onto a flat map - something has to give.

Link | Posted on Jun 14, 2017 at 14:47 UTC
On article First pictures from the new Nikon 8-15mm fisheye (139 comments in total)
In reply to:

GlobalGuyUSA: What focal length is a 15mm fisheye, if de-fished? 16mm? 17mm? 18mm?

More like 6mm equivalent.

Link | Posted on Jun 14, 2017 at 13:23 UTC
On article First pictures from the new Nikon 8-15mm fisheye (139 comments in total)
In reply to:

quietrich: "on the (mistaken) assumption that they will always create unnaturally distorted images"
'Distortion' surely refers to scale and perspective, as well as lines. Ultra-wide and fisheyes will always result in distorted images, distortion which we might or might not like; but it is unavoidably there.

All lenses cause distortion. This is because they are smashing a spherical world onto a flat surface. Since long lenses are smashing only a tiny portion of that sphere, the distortion isn't very noticeable. Ultrawides always create noticeable distortion because they are capturing so much of the sphere.

This issue is, what type of distortion is preferable for a given shot?

Rectilinear ultrawides keep straight lines straight but turn circles into ovals and stretch the heck out of anything near the corners.

Fisheye ultrawides keep circles circular and don't stretch the corners but they turn curved lines that don't point at the center of the image frame into curves.

Personally, I find fisheye distortion preferable to rectilinear distortion on about 98% of my ultrawide shots, and I absolutely love my Canon 8-15 on my crop camera where it's wider than the 11-24 on full-frame and can be fisheye or defished, in part or in full, to rectilinear.

Link | Posted on Jun 14, 2017 at 13:21 UTC

What would I use it for? I'm a fisheye-guy who has shot over 40,000 shots with a fisheye cameras precisely because such images make me feel more like I was there than any other. However, I also shoot at 200-1000mm very often.

In round numbers, you eyes can resolve like a 35mm lens on a 12MP full-frame camera, and they have digital zoom (you can see 180 degrees around you or focus on a small, fixed point and see details there). These VR gadgets don't come anywhere close to that, but that's what it would take to really make it feel real. And that's gigapixel level video if you do it 360x180.

Now where's my petabyte microSD card?

Link | Posted on Jun 6, 2017 at 20:16 UTC as 41st comment
In reply to:

DesmondD: It will be interesting to see what the results look like on dx.

I use my Canon 8-15L exclusively on crop. It's an incredibly flexible combination.

Think of the 8mm end as a single-shot 180 degree panorama.

Then, 9 to about 11mm is like a full-frame fisheye with variable focal length.

Then 11 to 15mm is something like a 14-22mm equivalent rectilinear zoom after defishing.

One of my favorite lenses and I use it all the time.

Link | Posted on May 31, 2017 at 12:18 UTC
In reply to:

AstroStan: As regards Bayer and astro-imaging (the following is of little or no interest to general photographers):

For serious astro-imagers there are additional problems and failures of Bayer not mentioned in the article. For example, non-terrestrial colors of astro-objects are poorly rendered by the Bayer filters. Green is arguably the least interesting astro color (esp for pretty pics) but green is over-represented by Bayer to the detriment of red (very significant Hydrogen-Alpha nebula emission). The Bayer filters themselves are absorption dyes with poor transmission and non-optimal passbands compared to optimised interference or dichroic astro-filters. The permanent Bayer filters virtually preclude science grade narrow band filters. There are other important issues but not enough space here to go into further detail.

Bayer is OK for casual nightscape/starscape using camera lenses or small fast scope but Bayer is poisonous for deep space imaging via real scopes.

Bayer doesn't do too bad for planetary imaging also.

Link | Posted on Mar 29, 2017 at 16:21 UTC

This is a really good article, but I would have liked to see a discussion about both types of dichroic filter approaches to solving this problem (multiple sensors, and filters at the pixel level) to make it more complete.

Link | Posted on Mar 29, 2017 at 14:54 UTC as 60th comment
In reply to:

Lee Jay: Simple - if I could only have one focal length for the rest of my life, I'd give up photography as a hobby.

Been married for a long time. An individual isn't one-dimensional the way a single prime lens is.

I have nothing against primes, as long as you have many of them. I used to have many, but zooms and sensors have improved to the point where I sold all but one of my primes (and then bought a different one so I have two now).

Focal length range is a HUGE deal to me. My basic carry-everywhere kit includes 180° horizontal fisheye through 640mm equivalent with no gaps. My total range goes much longer than that, out to something like 9,000mm equivalent before cropping in post.

Link | Posted on Mar 27, 2017 at 18:16 UTC

Simple - if I could only have one focal length for the rest of my life, I'd give up photography as a hobby.

Link | Posted on Mar 27, 2017 at 14:54 UTC as 161st comment | 3 replies
Total: 865, showing: 21 – 40
« First‹ Previous12345Next ›Last »