VLreviews

VLreviews

Joined on Mar 5, 2015

Comments

Total: 4, showing: 1 – 4
In reply to:

misterpepper: It seems so easy if you want to prove the "flat-earthers" wrong about climate change to just show some before and after shots. Not a few cherry picked shots, but some good sized areas showing a significant reduction in snow coverage. We can get past the resolution differences from 50 years of camera advancement. Let's say same week, every 10 years for 50 years. Make it 1970/1980/1990/2000/2010/2020 to avoid the temptation to choose the highest and lowest snowfall years. It should be easy to prove climate change that way, right? If not snowfall why not do the same with the coastlines? Surely 50 years of sea level rise should show us what kind of crisis we're facing. Why is it that the easiest, most convincing ways to show the real effects of climate change get ignored?

The data you are looking for does exist. A lot of it is publicly available, some is commercially available. Some examples of public data:
https://earthobservatory.nasa.gov/world-of-change/AralSea
https://earth.google.com/web/@37.57432243,45.55410048,1388a,268373d,35y,0h,44t,0r/data=CjYSNBIgM2ZkOTk3YWI0Njk4MTFlYTlkZWUyZGUyNWIyYWZmNjkiEHNocmlua2luZy1sYWtlczE
https://climate.nasa.gov/vital-signs/arctic-sea-ice/
https://earth.google.com/web/@61.05987082,-147.05927869,5a,22434d,35y,-23h,70t,0r/data=CjYSNBIgM2ZkOTk3YWI0Njk4MTFlYTlkZWUyZGUyNWIyYWZmNjkiEGNvbHVtYmlhLWdsYWNpZXI
https://earth.google.com/web/@80.6452526,-24.11033144,4a,237832d,35y,74h,54t,0r/data=Ci0SKxIgM2ZkOTk3YWI0Njk4MTFlYTlkZWUyZGUyNWIyYWZmNjkiB2ljZWxhbmQ

Link | Posted on Nov 13, 2021 at 15:15 UTC
In reply to:

trainingpants: Landsat 9 will produce stunning images and a wealth of new data about our planet, but please stop with the "climate crisis" and "devastation" nonsense unless you take the time to review the data yourself. Neither is true. You're just repeating the demonstrably incorrect climate-model-based hyperbole without examining the (lack of) evidence of any crisis or devastation. Measured global temperature rise since the late 1800's is about 1° C and measured global sea level rise since 1860 has been about 0.4 meters. The current rate of global temperature rise is about 1.4° C per century and sea level rise is about 0.3 m per century, far below the projections of the CMIP climate models and in line with their "no big deal" RCP2.6 scenario. I invite you to look at the global temperature and sea level datasets yourself to see that there is no crisis; just the glacially slow pace of natural climate change with perhaps some modest human influence from CO2 emissions.

https://www.carbonbrief.org/analysis-why-scientists-think-100-of-global-warming-is-due-to-humans

TLDR: Human influence is >=100% with very high confidence (earth would have cooled slightly without us).

Link | Posted on Nov 12, 2021 at 17:34 UTC
In reply to:

brycesteiner: The great myth perpetuated once again. Climate change? sure, it always has. There is nothing new. Droughts, blizzards, heat waves, cool waves. I remember when by 2020 Britain was going to be in a new ice age. I remember when the earth was all going to be burning up by now according to Bill Nye. Al Gore: "by 2013 there will be no arctic ice". By 2000 three states were giving up significant land to the ocean.... It just makes people disbelieve because we have yet to see any the predictions of the self-proclaimed experts.
Look back at the predictions of 40 years ago and see which were true.
Worldwide We don't have more storms, we don't have more rains, in fact how could there be if you have any concept of physics.
Now take the predictions of today's "experts" and laugh because the one prediction we know will be right is they will be wrong.

Just gonna leave this here:

https://www.carbonbrief.org/analysis-how-well-have-climate-models-projected-global-warming

Link | Posted on Nov 12, 2021 at 17:26 UTC
On article Why are modern 50mm lenses so damned complicated? (911 comments in total)
In reply to:

KrisAK: Pardon the interruption: is there a writeup somewhere for how one reads the OLAF charts? Is 0 on the x-axis (horizontal) the center of the frame, and -20/+20 the edges?

Also, with respect to edge sharpness: are test shots FOCUSSED at the edge? Or is edge sharpness based on shots focussed at the center? (I frequently put subject matter at the edges of the frame, and would like to judge edge sharpness when focussed at the edge; is that what I'm seeing here?)

0 Is the image center, +-20 mm is 20 mm away from the center, which would be very close to the extreme corner on a full frame camera (21.6 mm would be the tip of the corner). Left and right edge of the frame would be +-18 mm, top/bottom are +-12 mm.

Not totally sure about the lens orientation. I think all lenses are tested in the default orientation, where +-20 mm is to the left and right side and then additional tests are done rotated 90°, where +-20 mm would be up/down in a regular image. Resulst would then be then averaged for the graph. Might remember that incorrectly, though.

Lenses are focussed at infinity for all tests. There is no actual camera involved - only a detached mount and a special sensor behind it. I would have to search for the post where OLAF testing was explained in more detail, but if you are interested, check out http://www.lensrentals.com/blog/

Link | Posted on May 9, 2021 at 15:21 UTC
Total: 4, showing: 1 – 4