Site Sponsors
Page 3 of 3 FirstFirst 1 2 3
Results 101 to 105 of 105

Thread: P25 Plus noise test/ Very Boring sorry

  1. #101
    Administrator, Instructor Guy Mancuso's Avatar
    Join Date
    Oct 2007
    Location
    Arizona
    Posts
    23,623
    Post Thanks / Like
    Images
    2555

    Re: P25 Plus noise test/ Very Boring sorry

    Jack and I are planning a shooting getaway hopefully in a couple weeks . Jack has a P45 plus and i have the p25 Plus. We also noticed when we where shooting in San Juan the P25 Plus had a touch more DR. But we will try a few things
    Photography is all about experimentation and without it you will never learn art.

    www.guymancusophotography.com

  2. #102
    Senior Member
    Join Date
    Apr 2008
    Posts
    280
    Post Thanks / Like
    Images
    62

    Re: P25 Plus noise test/ Very Boring sorry

    Guy,

    Any chance of you doing the side by side exposure bracketing DR test between the P25+ and your D300. I'd love to see how much of a difference there is between the two.

    Thanks,

    Greg

  3. #103
    Administrator, Instructor Guy Mancuso's Avatar
    Join Date
    Oct 2007
    Location
    Arizona
    Posts
    23,623
    Post Thanks / Like
    Images
    2555

    Re: P25 Plus noise test/ Very Boring sorry

    Maybe in a week or two Greg on a book project that i need to get to printer by next thursday. Honestly It maybe as much as 3 stops but let's see what we get
    Photography is all about experimentation and without it you will never learn art.

    www.guymancusophotography.com

  4. #104
    Senior Member
    Join Date
    Apr 2008
    Posts
    280
    Post Thanks / Like
    Images
    62

    Re: P25 Plus noise test/ Very Boring sorry

    Quote Originally Posted by Guy Mancuso View Post
    Maybe in a week or two Greg on a book project that i need to get to printer by next thursday. Honestly It maybe as much as 3 stops but let's see what we get
    Sounds good, looking forward to it.

  5. #105
    Panopeeper
    Guest

    Re: P25 Plus noise test/ Very Boring sorry

    Suggestions for the comparison of the DR of cameras

    I see another thread started by Jack, which is becoming a comparison, even though Jack probably did not intend it as such.

    A comparison does not have to be objective, but if it is intended to be, then I suggest following tests in order to achieve measurable and directly comparable results.

    1. Scenery (of course with very constant illumination): it should include

    a. a smooth, uniformly colored (the best is some greyish), uniformly illuminated surface. It does not need to be large, even 100x100pix is enough, but if larger, then better, for one has to pick a clean and really uniform patch n it. This spot serves for measuring the noise in terms of standard deviation.

    b. something fine textured whatever, the best if if is not uniformly lit, i.e. it has transitional shades. Example: silk flower; some vowen greyish cloth. The distance should be such, that the fine details are very clear in good illumination.

    2. the lenses and/or the distance should be chosen so, that the pixel size of the fine structure is the same in the participating cameras. This spot has to be in focus as good as possible.

    This spot serves to determine how much details are captured at the dark end.

    3. Do not bother with fake ISOs; use only 100 with the Sinar and P25+. The P45+ has real ISO up to 800, if someone is interested on the ISO performance, one should shoot separate for each ISO with the P45+.

    4. Make one shot based on metering. This does not serve for comparison between the cameras, but for the measurement.

    5. Make one shot far (but FAR) above metering, at least two-three stops. This is to determine the saturation levels. It is mostly 65535 with the 16bit sensors, but with some cameras at some ISOs it can be substantially lower. This shot can be of anything, even a lamp.

    g. Now the core: underexposed shots, by 1/3 or 1/2 stops (whatever the camera supports), lower and lower. The evaluation will find the darkest shot, in which the noise is still acceptable and the details are good enough. For the DR it is irrelevant, which exposure this will be, the pixel values count. However, the shutter times should not be very far apart between the cameras, that's not fair. I mean if one camera shoots with f/2.8 and shutter speed in the range of thousandths, while the other camera shoots with f/22 and shutter in the range of tenths, then the noise comparison is not valid.

    h. Do not care for the highlights.

    If such shots become available, I volunteer to analyze the raw images and to demonstrate it, so that others can do the same. I do the analysis based on the adultered raw pixels, i.e. the result does not depend on which raw processor and how is used.

    Of course, this does not exclude any other method, and particularly, subjective aspects are important as well.

    Gabor

    P.s. please do not think, that I am asking for this. I do not plan to purchase any MFDB; I have not used my tank called Zensa Bronica for years, for it became too heavy for me (or perhaps I became too weak to carry it?).

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •