Once, not so for near sighted people. My wife can see my GG very clearly at 6 inches away without glasses. Several other LFers I know same deal and it has its convenience. Of course my wife is half blind at infinity without her glasses. Leonards case of an unaided one inch viewing distance from eye to GG is unusual - he must have been spectacularly nearsighted.
Nate Potter, Austin TX.
If you had read everything I said, you would have seen that I discussed that too. As it is, you completely misunderstood what I said.Originally Posted by Once
Neither of us has any idea whether beemermark can see clearly at 8 inches. He certainly can't in his corrected eye. Whether or not he can in his `bad' nearsighted eye would depend on his degree of myopia. Before I had my cataracts removed, I was so myopic that without my glasses I could see clearly at about 1 inch. Having started getting nearsighted at age 10, I've been able to see things clearly very close up until at age 70. The plastic lenses inserted during the surgery corrected my distance vision to 20-20, so now I need glasses to see anything at all close-up.
My guess from what he said is that he can't see things clearly at 8 inches, but I have no way to be sure. He would probably need some aid such as a magnifier or reading glasses to do that.
The point of his so doing would be two-fold. First, and less important, 8 inches, being close to the diagonal of the format, is the proper distance from the point of view of perspective. Second, by getting somewhat closer, he would be able to focus better. Whether he would be able to focus well enough at 8 inches would depend on how he went about it. I think he probably wouldn't, so I suggested he get a loupe for focusing purposes.
About 8 diopters correction plus astigmatism. My daughter is even more nearsighted. But cataract surgery and the resulting implanted lenses can work miracles. Of course, I still have the underlying eye structure that led to the myopia, so I'm at risk for retinal detachments and other problems. I've also, of necessity, learned quite a lot about vision over the years.
Sorry Leonard, it's just one big nonsense. How could "the proper distance from the point of view of perspective" to evaluate the scene be a distance at which one cannot focus with normal good vision - that is beyond me. As I said - this advice is just plain nonsense because it cannot be practiced. Your illness aside (goodness, it's not a normal vision!) - the normal vision cannot follow your "rule" at all. And a 6x6 format - you would like to "correctly" see it licking the film, perhaps?
Because your wife doesn't have the normal vision she cannot be a proof that a rule impossible to follow for people with a normal vision is a correct rule. The rule Leonard gives as advice is nonsense for people with a normal vision - therefore it cannot be a general rule.
Whew! Once! Many of my LF compatriots with normal 20/20 vision use plus diopter drugstore glasses to view the GG image at distances similar to what Leonard suggests. I use a plus 3 diopter at about 8 inches. This gives me a global view of the screen for the initial composition and initial standard adjustments. I then will remove the glasses and use a 5X loupe to ascertain critical focus in places where I need a critically sharp image.
I hadn't thought about the perspective deal mentioned by Leonard but it seems to make sense. If I'm using a 150 mm FL lens on 4X5 then I'll get a good sense of the scene by viewing the GG at 6 inches. Hmmm. maybe there's something to that. Although when using my 500 or 75 mm.I still view at 8 inches.
Nate Potter, Austin TX.
I agree with what Leonard has been saying. However, in two respects it was not as clear as it might have been. The first is that we have to recognize that most adults do require magnifier glasses (drugstore readers) to achieve the close focus he recommends. The second clarification necessary has to do with the word "perspective". I would argue that when the subject is flat as in an image on a ground glass, perspective is entirely defined by the angle that one views from. That is, if I am directly behind the center of the image, the relationships between the objects making up the image do not change if I am 6 inches away or if I am 10 feet away.
To me, the "correct" viewing distance for the ground glass is approximately the negative diagonal because that is analogous to how I like to view prints. That is, I view prints from a distance about equal to the print diagonal. This allows me to evaluate the total composition while still seeing as much print detail as possible. Closer than that distance and I can no longer view the composition as a whole.
I do recall some author suggesting that all prints should be viewed from the taking focal length multiplied by the print magnification, but I was not convinced. That viewing distance may render the print's perspective as natural, but in doing so it robs the print of the power of the exaggerated perspective which is often the reason for choosing a near or a distant perspective on the subject. (No to mention the awkward interchange required to compel each gallery visitor to move to the single designated viewing position for each print.)
You see, even you contradict yourself.
Have you ever seen people reading a magazine? Do they lick the paper when looking at a small, 6x6 picture to have "the correct perspective" or to follow Leonard's rule of normality that, for people with normal vision, cannot be followed without special optical means? And when they look at a paper spread they ask the neighbor to hold the picture so that they can back away? That's the normality that Leonard sells to photographers. No wonder, he doesn't believe that a photographer can easily focus at something 600 y far away or more...
Once,
I believe that all the near sighted / far sighted, proper perspective etc. etc. might have thrown you off a little. I read what Leonard wrote and interpreted it differently and hopefully I can rephrase things correctly as my method of focusing is the same as Leonard described, as quoted farther below. Leonard also wrote specifically for beermarks needs which I think is what may be confusing.
My vision is good at near 20/20. To initially evaluate a scene I keep my head back from the ground glass and try to place all the elements in the whole scene in a nice composition on the ground glass. I can do this without any magnification as I know by looking at the scene what the elements are when looking at the ground glass. All the parts of the scene are sharp on the ground glass but they still look far off. If I use reading glasses (3 X is what I use) the overall scene on the ground glass is brought in to closer focus which is very helpful. The desired scene can now be easily be composed looking at the whole ground glass.
Now that I have the scene composed and want to more closely focus on the far elements, and then the near elements, to set the best depth of field and focus spread, I use the loupe which is even more powerful.
This is probably a typical means of focusing for most people with normal vision.
I hope this rewording is helpful.
Leonard wrote
“For evaluating the scene, you should put your eye at about the diagonal of the format from the ground glass. I don't have a 5 x 7 to measure, but I would guess that would be about 8 inches. If you can get that close with your uncorrected eye, then use it for framing and generally evaluating the scene. If not, you would need some sort of magnifier or special glasses. (A loupe usually won't work for this because it has too narrow a view.) Viewing the scene with the proper perspective is often ignored, and I find it helps me enormously to do it.
For focusing, on the other hand, you should put your eye closer to the ground glass, and I would doubt that you can get it close enough on the basis of what you say. A loupe lets you in effect put your eye closer, so in principle you should use as powerful a loupe as you can find. But if the loupe is too powerful, you won't be able to distinguish surface features of the focusing screen from the image. The usual advice is not to go much higher than 4 X, and for many purposes 2 X will suffice.
Dave,
your rephrasing is not what Leonard gives as advice and your method of focusing isn't either.
Leonard's "rule" to see the gg at a distance impossible for people with a normal vision to use without a special optical device is nonsensical. You too you don't look at the gg from that distance. What kind of glasses you use is completely irrelevant to the "rule" Leonard proclaims as -a "correct" one.
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