Erik's web

  • Increase font size
  • Default font size
  • Decrease font size

My MFD Journey, summing up - Dynamic Range

E-mail Print PDF
Article Index
My MFD Journey, summing up
Dynamic Range
An odd comparison
Some thoughts on real world images vs. formal testing
On economy and feasibility
Raw images and links
Comparison P45+ vs. Sony Alpha 99 (raw images)
All Pages
Dynamic range

The raw histograms of these two images processed by RawDiger are shown below:

Full size JPEG
fill in info please
Full size JPEG
fill in info please

We can see that the histograms are similar. But we can also see that the histogram on the SLT drops much more rapidly on the SLT99 compared with the P45+. The P45+ has counts down to -12 EV, but the Sony (SLT99) goes only to -8EV. That difference is probably caused by the P45+ having more readout noise. We can see that -8EV corresponds to about 30-40 counts. Each count may correspond to an electron charge, by and large, assuming 60000 electron charges of FWC. If we assume something like 16-20 electron charges of readout noise we would expect the noise spreading down to a couple of EVs, this is what I think we see.


The images below are shown "as is". Exposure was increased 4EV and the noise reduction paramaters are set to zero but I am still using sharpening, without sharpening the noise is even more ugly. In my view the Sony image has less and better noise.

 

Full size JPEG
P45+ in LR5, no noise reduction but sharpened
Full size JPEG
Sony 99 SLT, no noise reduction but sharpened

Colour rendition

A more extensive aticle on colour rendition is posted here.
I have created DNG profiles using an Xrite ColorChecker, using Adobe's DNG Profile Editor and with QPCard card and software. The images below show a P45 image processed using LR5.3, Capture One 7 and RawTherapy, an image from my Son Alpha SLT 99 is include for comparison.  The images in LR5 were processed to my taste. The Capture One image was processed as well as I could, on RawTherapee I am just a beginner. Color balance interpretation differs. C1 is warmer than LR5. Other than that I don't think it is a world of difference.

 

Full size JPEG
P45+ and Capture One
Full size JPEG
P45+ and LR5
Full size JPEG
P45+ RawTherapee
Full size JPEG
SLT99 + LR5

Below I compare LR5 rendition of the P45+ and the SLT image side by side, both use camera white balance, and both are processed to my taste, so they are not suppoed to be identical.

 

Full size JPEG
P45+, with dual illuminant profile created by Adobe DNG Profile Editor
Full size JPEG
Sony Alpha 99 with Adobe Standrad profile

Aliasing

The main article is: here.

Aliasing arises when lens resolution exceeds the resolution of the sensor. Aliasing creates false detail, mostly observed as moiré. What I see is that a very significant part of my images show some color aliasing or moiré. This is a disadvantage of today's medium format, where sensors don't match the resolution of the lenses and the sensors lack OLP filtering.

 
Full size JPEG
P45+, f/8, max sharpness but significant colour aliasing
Full size JPEG
P45+, f/11 aliasing little affected by diffraction
Full size JPEG
P45+ Aperture f/16, most aliasing gone



Last Updated on Thursday, 13 February 2014 13:29  

Statistics

OS : Linux u
PHP : 5.2.9
MySQL : 5.0.67
Time : 08:16
Caching : Enabled
GZIP : Disabled
Members : 1510
Content : 72
Web Links : 1
Content View Hits : 403608

Login

Banner1

J!Analytics