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11-22-2015, 03:24 AM - 1 Like   #46
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QuoteOriginally posted by stevebrot Quote
The CFO at a company I worked for once remarked, in regard to QA, "We prefer to let our fruit ripen in other people's baskets".
Ah, product development "in partnership with our customers"

11-22-2015, 04:14 AM - 1 Like   #47
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QuoteOriginally posted by pathdoc Quote
I ever get back to Adelaide, God knows when, I seriously need to come look you up and see how you do what you do
I'm nothing special, I put my camera straps on one lug at a time...
11-22-2015, 06:53 AM   #48

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QuoteOriginally posted by stevebrot Quote
That is unless you were planning on printing and put the negative in an enlarger. Grain focusing was and remains the standard. That being said, I would routinely evaluate negatives with a loupe prior to attempting an enlargement. Depending on the loupe, the magnification is about the same as viewing at full resolution on screen.

A 24M FF sensor is providing 4233 dpi, a typicall desktop screen is providing 100dpi. So a 100% crop is a displaying the picture magnified 42 times. With a 50MP this magnified 60 times.

Want to see better theses little pixels? Well you are just a slider away from 200% meaning you have 80-120X magnification.

This is quite significant. While I don't doubt a few were looking at their negative with such high level of magnification back in time, I don't think this was common usage.

Now the guy with the most basic tool ever is going to be a able to see what a 100% crop look like on his screen.
11-22-2015, 07:34 AM   #49
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QuoteOriginally posted by Sandy Hancock Quote
Make sure you look me up too....
By all means. At this stage we'll be gathering to take photos of the frozen core of Hell, but you never know.

Melbourne, on the other hand, is a far easier "ask" as I have business there once a year. Only problem is weather at the departure end makes it difficult sometimes to be sure of my exact arrival date.

11-23-2015, 10:04 AM   #50
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QuoteOriginally posted by Nicolas06 Quote
A 24M FF sensor is providing 4233 dpi, a typicall desktop screen is providing 100dpi. So a 100% crop is a displaying the picture magnified 42 times. With a 50MP this magnified 60 times.
As you said, it depends on the resolution of the display. For example, on the K-3 rear LCD full resolution is 8x. The human eye is able to resolve detail to about 1 arc-minute. I am not going to bother with the calculations as to what that might be with an 8x loupe on a light table or with a 20x grain magnifier on a 35mm frame magnified to 16"x20". The point I made was that critical evaluation of image quality is nothing new and that the usual tools provided a comparable means to measure. Anyone in the business of purchasing photos for publication as well as those selling knew how to assess quality and the standards were as high then as they are today.

As you point out, the main difference is the ease with which someone with nothing better to do might assess an image.

11-23-2015, 11:06 AM   #51
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I have a calendar on the wall near my desk that I use to test newly acquired lenses. I usually stand back about 10-15 feet and take several shots of this calendar including the small print to see how well the lens is rendering. I also use a clock that is hanging on the wall in my living room. If try to find a lens with a reasonable focal length to compare against the new lens. For example I'm not going to compare a 50mm lens against 100mm lens that's ridiculous. However sharpness is not the only thing to compare against, there is also contrast, color rendition and flare resistance. Once all that is settled I either keep the lens or send it back...

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