lupes & failing eye sight

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Having hit the 56, my eye sight is not as sharp up close as it once was---as the world turns------What are some suggestions re: lupes, power, for focussing on ground glass for my age group? I'm questioning my present lupe, it's power & it's shape which is a round Omega purchased from Calumet years ago (power??). Thank you--Raymond A. Bleesz

-- RAymond A. Bleesz (bleesz@vail.net), September 03, 2000

Answers

Raymond - One thing to consider is the purchase of a focusable loupe. Loupes are best used in combination with one's distance spectacles, or if you remove your specs to view the image, with a loupe that can compensate for the absence of the distance prescription by altering the power. If you are somewhat farsighted, you may be experiencing some increasing difficulty viewing the loupe's image clearly unless additional (+) power can be dialed into the ocular. HMF

-- Henry Friedman (friedlew@worldnet.att.net), September 03, 2000.

Have an optometrist fit you with glasses that allow you to read comfortably at a short distance, say 4-5". Then get a 4x focusing magnifier with adjustable eyepiece, and use it in conjunction with these glasses for focusing. The eyepiece setting is determined at home and taped in permanent position.

So in the field you will find yourself with a viewingfilter, magnifier,close-up glasses hanging from cords around your neck. Then add to that the bi- or trifocals you are going to take off under the dark cloth.

The close-up glasses are also useful for print spotting, contactprint inspection etc. I have pair in the darkroom as well as in my LF camera back pack.

You can also switch to a medium (or 35 mm!) rangefinder, if you want easier focusing.

-- Hans Berkhout (berkhout@cadvision.com), September 03, 2000.


I bought 2 pair of "drug Store" glasses +2 diopter and popped the lenses out of on pair and siliconed them to the intact pair-Viola! +4 close up glasses. For me they focus @4" enough to view the entire 6x7 cm gg. For critical work I use a 3.8 Toyo loupe afterward. George Nedleman

-- George Nedleman (gnln@thegrid.net), September 03, 2000.

You might like a loupe that clips on to your glasses and swings into and out of your line of sight. Behr Manufacturing of Wisconsin makes and sell the ones I have used. Don't know the web address but a search for Behr Manufacturing will find them.

-- John Hennessy (northbay@directcon.net), September 03, 2000.

Here's the address for Behr. I use one of their units. It works great!

http://www.excel.net/~behr/

-- Alec (alecj@bellsouth.net), September 03, 2000.



Ramond, I am seven days away from the big 63, so I know what you are talking about. I bought a pair of cheap +4 diopter glasses at a dollar store that let's me focus quite close to compose the picture. I made a loupe out of a piece of PVC pipe and a 50mm cheapie enlarging lens that outperforms any I have ever seen. You can measure the distance from the lens to the ground glass with the lens held to your eye and then cut the pvc to length. Cut the pvc a touch long and then you can carve and sand it to perfect focus. It is the best one I have ever used. I made mine to focus without the reading glasses. I am very fortunate that my distant vision has held up remarkably well, I just can't focus close.

Hope this helps, Doug.

-- Doug Paramore (dougmary@alanet.com), September 03, 2000.


Although I don't need glasses, yet, I find using a 4X Loupe from Schneider to be a helpful tool. The loupe is also "focusable". When choosing a loupe for use on the ground glass, be sure to choose one with an opaque housing, and NOT one suitable for viewing prints. The transparent portion of such loupes allow too much ambient light in thereby making focusing more difficult.

-- William Levitt (light-zone@operamail.com), September 03, 2000.

I bought a jewelers headband/visor style loupe from a local electronics store. It flips up and down and I can wear my regular glasses if I want underneath it. There are several diopters of lenses that snap into the visor. Total cost was ~ $20. The visor also shades the sun so I don't alway need to be under the dark cloth. Got the idea from my dentist who uses one when working on my fillings!

-- Glenn Kroeger (gkroeger@trinity.edu), September 03, 2000.

Raymond: In 4X5 LF photography you need to see things at two different magnifications. To compose I find it best to limit the view to what is in the GG so you I can see the whole image as big and sharp as possible. That means you need to bring the eyes to about 150 mm from the GG and for that you need a prescription. The view through prescription glasses will be sharper than that from drugstore glasses because any of your eyes aberrations will be corrected by the prescription. Additionally, drugstore glasses have the same dioptre on both eyes and with yours, as with mine, you may need different dioptres. Prescription glasses are more expensive than the drugstores but for me they have been worth every penny. It is amazing how sharp things look on the groundglass with these glasses. For these whole-image glasses pick a style that is fairly narrow (vertically) and have the frames adjusted so that you can drop them down your nose a bit when you need to see farther out. (For that you may still require your regular glasses; that will depend on your eyesight) Do not pick reading style frames, the ones with the glasses way down the nose because with those you would need to raise your head very high when viewing the GG.

I find it more convenient to separate this whole view from that required for precise focusing. For that I remove the whole image glasses and use an 8X adjustable loupe. The 5X and 6X loupes magnification I find not enough, while the 8X I find just right. More than 8X can be troublesome as it conflicts with the grain in the GG.

With regard to loupes, designs vary. Some 8X loupes are very shallow and require you to bring your nose right against the GG, which is cumbersome and may cause fogging of the GG. Others are of longer design and permit keeping your eyes further out from the GG. Some loupes consist of several elements and can provide very sharp images. I use a Horseman 8X loupe, perfectly adequate although not of the latest several element design.

The above will have you wearing two kinds of glasses plus a loupe. You get used to it. At our age, Raymond, that is the price to pay. Good luck.

-- Julio Fernandez (gluemax@ora.auracom.com), September 04, 2000.


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