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Untitled

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My goal on this page is to be able to set up a sample calculation of system resolution. I still have some of the charts from my Master's thesis that can be put here as original artwork. User:Ehusman 21:45 26 November 2005 (UTC)

I changed the MTF page to a redirect, the original content is here:

The Modulation Transfer Function (MTF) is a property of imaging systems. It is the transfer function of a lens: that is, it is the amplitude of the Fourier transform of the response of a lens to a point source. Ideally, this is flat, but due to diffraction and aberrations it decreases with increasing frequency in all optical systems. The MTF also depends on how far from the optical axis it is measured, and tends to be worse further off the optical axis.
Equivalently, the MTF is the response of an imaging system to a series of black and white bars at a given frequency: the contrast between white and black bars of the imaged system is equal to the MTF of the optical system.

This seems like a ubtopic to the main discussion of optical resolution in general. --User:Ehusman 21:45 26 November 2005 (UTC)

Transmission resolution

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The addition of the transmission resolution information by 203.4.236.77 does not fit in with the rest of the page. That information belongs where it already exists: on the display resolution page. The purpose of the Transmission resolution section on this page is to explain how analog transmission impacts image resolution (i.e. by acting as a low pass filter). I am open to suggestions on how to incorporate both, but I believe the display resolution (especially digital display, e.g. HDTV) is a separate subject that belongs on a separate page. Unless anyone objects, I am going to revert the edit and change the section heading to "Analog transmission bandwidth effect on image resolution", or something like that. Ehusman 17:04, 30 January 2006 (UTC)[reply]

It is done, I hope you like it. If someone would like to get into the discussion about the effect of changing digital resolution by sub- or super-sampling (i.e. from XGA to VGA, etc.), I think that deserves a new section. Ehusman 20:37, 4 February 2006 (UTC)[reply]

Ultra-high resolution cameras

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I'm not enough of a specialist to decide where (which Wikipedia article, which paragraph) and how to cite it, but I think the Gigapixl Project could deserve at least mentioning, if not its own article. --Olivier Debre 13:04, 28 August 2006 (UTC) I found another similar curiosity: Clifford Ross' R1/i3[reply]

I create the stub for Gigapixl Project. --Olivier Debre 09:58, 8 September 2006 (UTC)[reply]

Technical

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I moved the technical tag to here. Whoever placed it would do well to join the discussion and say why or what is suggested. Dicklyon 18:40, 12 April 2007 (UTC)[reply]

Does this Wiki need or wants photos?

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Would it be appropriate to add photos of various test charts to this wiki? (such as is shown on the USAF 1951 wiki page)Greif 20:32, 23 May 2007 (UTC)[reply]

Yes, of course, assuming you don't have licensing issues. Dicklyon 00:45, 24 May 2007 (UTC)[reply]
Ditto that. Of course, a photo of a 1951 chart should not have a licensing issue, but scraping one off of the page of a manufacturer would be problematic. On the other hand, it is a well-known chart and it shouldn't be too much trouble to draw one from scratch. The same may be true of other charts (Siemens Star, etc.). Ehusman 01:04, 26 May 2007 (UTC)[reply]

I added a link at the end (external links) to my page with a vector format (EPS & PDF) of the EIA 1956 chart, done by George Ou based on a scan I did of a physical copy of the chart from Edmund Scientific. The PDF is quite precise; more accurate than any photo, I believe. Bealevideo 22:04, 7 November 2007 (UTC)[reply]

Resolutions, comparisons, and non-square pixels

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A discussion concerning the issue of comparing analog and digital resolutions and comparing non-square pixel resolutions with others and square-pixel resolutions has been started here as part of the Broadcast Engineering and Technology Taskforce of WikiProject Television. Please discuss these issues there so that as a community we can come to a consensus. --tonsofpcs (Talk) 18:04, 16 July 2008 (UTC)[reply]

Spatial Frequency and Resolution

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It seems to me that resolution should have units of inverse length, such that high resolution has the appropriate meaning. That is, it should be a spatial frequency, not a length. Digital devices are commonly quoted in DPI, dots per inch, not in inches. I could dig out my old optics books to see how they did it. Gah4 (talk) 22:39, 19 September 2011 (UTC)[reply]

I was going to say something about this, but it seems that I wrote about it 8 years ago, with no comments since. I suspect that it is the WP:RS that start this confusion, so I suppose we are stuck with it. Gah4 (talk) 01:47, 6 December 2019 (UTC)[reply]

MTF problems...

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The sections about the OTF is overly simplified and makes the implicit assumption that the point-spread-function is shift invariant - that is the requirement for transfering the problem to Fourier-space. Parenthetically that basic assumption also makes it impossible for MTF to account for aberration since aberrations lead to spatial variations in the size and shape of the point-spread-function. In my opinion this simplifying assumption should be made clear. (I've had to work with aberration-limited optics, but I'm not at the moment ready to change the text.) — Preceding unsigned comment added by 129.242.167.30 (talk) 21:00, 4 November 2014 (UTC)[reply]

angular frequency

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This article sometimes mentions angular frequency, sometimes parenthesized such as spatial (angular) frequency. This is confusing. Angular frequency is often used to describe frequencies measured in radians/(unit) instead of cycles/(unit), but I don't think that is the case here. Optical imaging systems are commonly described using spatial frequency, often in line pairs/(length unit). I suspect that in some places they are considering the angle at which light comes through an optical system, and hasn't yet formed an image. In any case, it is confusing as written. Gah4 (talk) 14:23, 13 August 2018 (UTC)[reply]