centrax

Joined on Oct 8, 2019

Comments

Total: 9, showing: 1 – 9
In reply to:

Boss of Sony: Who is going to buy a desktop computer with 256GB storage in 2021? This is the one thing I dislike about Apple. The reasonable pricing of their base models is intended to draw the attention of buyers, until the buyer realizes the base model is a toy and they will need a higher model if they want to use the computer for what it’s intended (serious work).

>Who is going to buy a desktop computer with 256GB storage in 2021?
My wife, my mother, my children, my boss... should I continue?

Link | Posted on Jul 15, 2021 at 19:50 UTC
In reply to:

Tom Goodman: A maximum of 16GB Ram will hamper anyone with creative needs right out of the box.

OS X is considerably more memory efficient than MS Windows. With 16 GB you can as much as with 32 GB in Windows.

Link | Posted on Jul 15, 2021 at 19:49 UTC

I heard a rumour that they are working on a new version of USB-C that will allow fast charging for electric cars. :-)
And seriously, I wonder how many insertions the contacts/sockets will withstand under a 240W load. This can be a very unreliable solution, and costly to repair.

Link | Posted on May 28, 2021 at 16:29 UTC as 7th comment
In reply to:

centrax: Note that the Hubble telescope has a focal length 57600mm and f/24.

@mehdi78
It appears from my calculations that the Hubble's 16 Mpix Wide Field Camera 3 crop factor is about 100. The sensor is square. Note that for NASA this is "wide angle".

Link | Posted on Oct 10, 2020 at 18:27 UTC
In reply to:

centrax: Note that the Hubble telescope has a focal length 57600mm and f/24.

@mehdi787
Crop factor? This is terribly complicated because the telescope has several light paths and for each wavelength range it has one or more sensors with different crop size, number of megapixels and other parameters. Probably the picture in the article is a superposition of raw images captured by several sensors. It's a scientific instrument, not a normal camera.

Link | Posted on Oct 10, 2020 at 17:59 UTC

Note that the Hubble telescope has a focal length 57600mm and f/24.

Link | Posted on Oct 8, 2020 at 21:23 UTC as 2nd comment | 3 replies

Interesting. Doctors could get a detailed 3D model of the patient's interior from several X-rays.

Link | Posted on Aug 13, 2020 at 17:20 UTC as 6th comment | 1 reply

Poor man's Magic Lantern? :-)

Link | Posted on Oct 10, 2019 at 16:37 UTC as 15th comment | 1 reply
On article Sony a7R IV review (1482 comments in total)

It's a nice camera, with plenty of pixels. But does it make sense? IMO, not.

Because of the diffraction, the minimum aperture for a 61 Mp full-frame camera is f/5.6. Given that the sweet spot of a typical lenses is f/8, the max. sharpness can never be reached. Even if we have quality lens where the sweet spot is not a problem, we are still limited to rather shallow depths of field. In reality, most of the time, the pricey 61 Mp camera will take no better photos than a 30 Mp camera.

From my practical experience, I learned that there is (almost) no benefit of having more than 24 Mp in a full-frame (here the min. aperture due to the diffraction is f/9). Some people prone to illusions (and camera sellers too) have a different opinion.

There is only one method of having more real pixels - go medium format.

Link | Posted on Oct 8, 2019 at 15:45 UTC as 235th comment | 5 replies
Total: 9, showing: 1 – 9