Joined: 02 Jun 2016
Location: Bellevue, WA
|Posted: Fri May 19, 2017 4:37 pm Post subject: Line scan sensors - has anybody tried this for macro?
|In other threads I and others have been discussing the SK 85mm f/4.5 macro varon lens. It is an example of a modern macro lens designed to be used with high resolution line sensors.
The simplest line sensors are a single row of pixels, but there are fancier ones that have 3 or 4 rows so they can do color. The highest resolution line sensors these days have 16K pixels, which are typically 5 microns across, but they exist in all sizes.
Here are some examples
They are used for machine vision systems - an example is quality control inspection of manufactured circuit boards. The line sensors are cost effective because they are MUCH cheaper than a rectangular sensor of the same size. In these systems the subject to be photographed is mechanically scanned past the line sensor.
Well it finally dawned on me that instead of buying lenses made for line sensors to use with my camera sensor (for me these days PhaseOne 100 mpixel), I could also use one of these line sensors to make a scanning stacking camera.
This would mean moving the camera very accurately across the subject. But the requirements do not seem very difficult - on a single line camera, it would mean moving by one pixel width, which is 5 microns. Many of us have built stacking systems that have much more resolution (in depth).
With a multiline camera, it would be a multiple of that.
In the past there have been scanning backs for large format cameras like this. The Seitz 6x17 digital does something like this:
The difference is that this would be made for stacking, so it would be stepping in two axes - the depth axis as for normal stacking, and the side-to-side axis.
Obviously it would only work for static subjects, but stacking is already like that. One would need to figure out a way to focus and compose efficiently.
Has anybody on the forum tried something like that?