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New: SD Q Color Match to Established Style (high res target)

Started Apr 3, 2018 | Discussions thread
D Cox Forum Pro • Posts: 32,979
Re: Pixel Size. Crop Factor: Image Size Riddle.

Paul Thacker wrote:

Neither crop factor nor pixel size explains what I am presenting.

Imagine we have an 8x10 camera focused and framed on some western landscape with a normal 300mm lens. We load a holder. Slide into to place. Pull the darkslide. Trip the shutter. Replace the darkslide. Pull the film holder.

Now we take off the 8x10 film plate holder and replace it with a 4x5 reducing back and make a picture. Once processed, we will be able to exactly register the details from those two negs on a light table. This is why crop factor is not what is being discussed.

Film doesn't have pixels. (Until you digitize it.)

And none of us would ever consider or think reasonable that as pixel size decreased and pixel count increased that the actual optical image size would change. Get smaller.

What is in your computer is not the optical image but a list of the brightnesses recorded by an array of pixels. Change the number of pixels and the length of the list changes.

These two pictures should register perfectly like the sheet film example above. Why there is such a huge difference between these two exposures is beyond me.

SD14 white. SD Q black. Same lens. Same focus. Tripod mounted 70-210/2.8.

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Paul Thacker
www.paulthacker.com

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