Lives in Germany Germany
Works as a Physicist
Joined on Jan 10, 2010


Total: 2, showing: 1 – 2
On article Throwback Thursday: Sigma SD1 (239 comments in total)
In reply to:

MrImprovement: Have used the similar dp2 Quattro (yes, sensor is slightly different) and what I can say is that the image quality at ISO 100 is superb, although there are caveats, as others mention.

Re: mrgum's continual slagging of Foveon sensor: absorption of colors at different layers of silicon is well-studied, and used in many other applications, not just Foveon. Google "silicon spectral transmissivity image sensor" for instance.

You can see that the sensor does reproduce color, so exactly what is being absorbed at what depth is a false criticism: the sensor does reliably reproduce colors.

Metameric errors go together with color resolution. If you want fine graded colors, you have to accept that metamerism can occur.

You are wrong here, real RGB sensors with very little spectral overlap are not able to distinguish colors which are in the spectral bands without overlap. Color accuracy goes down. Not that great!

You see the Foveon in a wrong way. It is a 15MP sensor which acquires all three colors at each pixel site. Therefore, it has a resolution advantage of factor 2 for G and 4 for R and B. But because the de-mosaicing algorithms for Bayer are quite good, the resolution advantage "overall" is just a factor of 2.

Anyway, back in time when the SD1 was released, a 30MP camera was at the top of what you could buy.

Link | Posted on Sep 29, 2017 at 15:50 UTC
On photo Memento mori in the Pictorialism challenge (8 comments in total)

Memento mori? A bit far-fetched in my opinion.
Pictorialism? For sure not! Interesting that it was accepted as an entry.
BTW, I don't like the composition (with that dark part of the foot in the foreground).

Link | Posted on Feb 17, 2010 at 11:30 UTC as 4th comment
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