Memorial day in McFarland

More as an experiment than anything else I shot this from the hip. Or more accurately from hanging down around the neck where I pointed my D7000 is the general direction of the girls and tapped the shutter while I was walking.  As soon as they passed, Charlotte's mother caught up with me and said quietly, "I hate to think about it, but those two are Charlotte in a couple year.  Cute, popular, and walking around with the latest high tech toys."

Charlotte now.  Her high tech toys are upstairs waiting to be unpacked. She moved into a new home in McFarland this weekend.  So how high tech is this kid? A few years back when she was five and three quarters, she sat me down and told me I needed a new computer with more bandwidth. Her online games were playing 'tooo tooo sloow.'  And if I also tossed in some Barbie dolls, she might let me babysit again.

End result--if she's not hogging the big screen TV downstairs, she is cycling between her Barbie cluttered bed/toy room and this computer.  Kids rule in this house.

Now a pairing of images:

The first one was a for-sure flickr post but I didn't know what to do with the second one.

A few days ago during  Half Price Books  20% off sale I picked up a copy of 'the photograph as contemporary art' , Charlotte Cotton, Thames&Hudson, world of art.  This morning I was reading Chapter 2 "Once upon a time." To quote: "This area of photography practice is often described as tableau or tableau-vivant photography, for pictorial narrative is concentrated into a single image, a stand-alone picture."

This image certainly isn't museum grade art (like some I've seen hanging in museums)  and pairing the two is sort of cheating.  They were, however, taken a few minutes apart.  First the popcorn girl, then across the street to Charlotte and her ice cream, and finally inside to check out the Historical Society's bake sale.  A sequence that was meant to be.

But, given this high tech world, I didn't want to embarrass the overweight girl in the unlikely but not impossible event she saw it.  She might even flickr mail me an enraged complaint.  (Which did happen a few years ago but that is another tale.)

So into the blog it goes.  Where I know she and anybody she knows will never see it.

A new look

For years I've been looking a my blog and telling myself I should do something about the format that forced me to post ridiculously small images. After this was a blog about photography.  But I never did anything except add a line saying 'click and thou shall see large.'


Part was 'procrastination thy name is scribble.' Part was an ancient fear from olden days that I might end up having to edit some HTML code.  Been there. Done that. And folks I do know how to mess up HTMl code big time.Then, in the spirit of spring cleaning, I poked around a bit in Blogger and saw how simple it was. A new template, a few slider adjustments and done. 


Might even do a post or two with just photos and no theoretical  stuff.  Now that is a wild idea.

D7000 noise- part 2

Quick question.  Which patch has the least amount of noise. The one with the line profile under the image? Or the one with the line profile beside the image?

Actually nether. It's the same patch. In the bottom graph I measured 125 pixels. In the side graph I dragged the line out so I measured 1200 pixels.  Because ten times more noise wiggles were compress together the line is darker and looks noisier. This complicates things especially when comparing cameras with differing numbers of pixels.

From now on graphs are for info only.  I'll be posting result boxes showing the rms mean value (signal) and sdev (standard deviation or noise) Using these numbers I'll calculate the S/N numbers for any comparisons.

Yesterday I ate a few crow feathers in the D7000 thread. I'd blindly taken imaging-resource's word that they had measure the lighting for the D700 ISO6400 image. One look at the EXIF info and it was obvious that instead of  11 lumens, the lighting you find on a well lite street at night--the lighting used was more like 30 lumens.

My only excuse for such a stupid mistake is up to now I have been using my blog as an online lab notebook.  So I was free to changed my mine latter if I goofed.  After all nobody read my theoretical posts. Until this one caught peoples' attention. So my apologies for any confusion and on to what really is happening.

A way to correct for the lighting differences was to search out for areas in the images that had the same signal and then compare the noise. When I did it for the highlights, the black circled areas, it was definitely Oops.  The D700 beat out the D7000 by coincidentally 1.44--the magic noise number for a pixel twice bigger than the D7000's pixel.

Things become more interesting when I did the same thing for the shadows. I chose the second dark patch for the D700 (blue) and an area on the frame of the Dave Box for the D7000 (red).  The result box says it all.  Down in the shadows the S/N was identical.

I suddenly had some interesting ideas on what was going on, but since I was dealing with one set of suspect data, I certainly didn't have a convincing case. Even in my own mind.

Then d.brodsky posted a link to his images of the same scene, one taken with a D7000 and one with a D700. He provided a second data set.
(Click on the clips for full size and readable images)

The EXIF info says the  images were taken with two different lens so the exposures weren't exactly identical but I did find areas where the signal values were close.  The result boxes show that with real world images the noise reduction in the two cameras can smooth the noise out to were the signal to noise is nearly identical.

So my current thinking that Nikon's noise reductions routines are sophisticated.  Besides the obvious settings-- off, low, normal and high-- the algorithm looks at the S/N in the various areas of the image.  If it is in a highlight were the S/N is high it uses little or no noise reduction. If it is the shadows it uses a lot.

So if you compare images by looking at the bright areas where the noise is easy to see, the pixel size difference is important. But if you are digging detail out of the shadows the two camera may give the same results.

My plans are to uses my D7000 to figure out what is going on. But it might be a while before I post again since the computer I'm working with is going back to the shop for warranty repairs. Who knows how long that will take.

And finally a special thanks to d.brodsky for sharing his images.