focusing loupe?

How good are your eyes?

Seriously, I have used the 7x Horseman loupe for 30 years. I actually use a Jeweler's head piece more now, since I can't see close up as well. The lower power on the goggles part lets me see the whole ground glass magnified and then I have a swing down magnifier for critical focus. It looks funny, but it really works well when you eyes start to go! I still carry and use the loupe, but use it more for harder to see situations where focus is more difficult.

I prefer about x4 power, perhaps up to x6. I find that higher powers don't let you see more. They tend to magnify the grain of the ground glass and make a dimer image, more than they reveal finer detail in the image.

A 4 to 6x focusing eyepiece loupe. Although Linhof's one is 8x.

I use Fuji 4X loupe and it is great. You can find them brand new on ebay for $25.

I like old slide projector lenses. Some touch the glass and some stand off a bit (good for wide angle lenses because you can tilt the loop to check focus on the edges of the image.) They are easy to come by because people are moving to digital for home viewing. You may already have one.
They have the added advantage of being a larger diameter than most loops and allow you to view a larger area. They don't have anything to protect the ground glass from scratches, so put some tape on the front edges for padding. Their biggest disadvantage is weight. they are a lot heaver than a regular loop, Those big glass anastigmat lenses come at a cost.

I posed this question several years ago and the consensus was a 4X loupe was an excellent choice. I ended up buying a Toyo loupe that I believe is 3.6 or 3.8. It has worked perfectly for me. Several of the threads discussed the problems of too much magnification and warned me to stay away from loupes that were 10X or higher.

Paul

My favorite loupe is a 50mm lens from a 35mm camera. Look through the rear and they make nice bright, well corrected loupes and can be found very inexpensively. I think I paid $5.00 for my last one that was mechanically challenged, but optically good. I put on a rear cap that I have drilled out with about a 1 inch diameter hole to protect my eyes from the metal lens mount. The 50mm Nikon Series E lenses are my favorite because of their nice light-weight construction. I also use one in the darkroom for inspecting negatives.

Recently, I tried my fathers reading glasses (-4 diopt or so) and I was pleasantly surprised. I had to move my head closer to the ground glass, but my view was not limited to the area of the loupe and at a certain distance everything was big, clear and sharp, kind of 3D... I'm seriously considering those glasses as my only magnifier and will eventually end up leaving my loupes at home.

To answer your question, the vast majority of my work is focused with a 4x Schneider loupe, on rare occasions I use a Horseman 7x loupe for critical focusing with wide angle lenses (90mm and shorter).

Believe it or not, the best thing I've used was a hand held magnifying glass of unknown magnification that I bought at The Dollar Store. I liked it because it would work even w/ the focusing hood on my Crown Graphic. Now I use an old Polaroid reflex viewer and not only does it flip the image right side up, it also has a built in magnifier in it.

I second the jeweler's goggles as suggested by John A. but a strong set of reading glasses will do just as well as indicated by John L. The problem with the latter is, AFAIK, the really strong ones are prescription only. I don't think I've ever seen stronger than +2.75 OTC.

EDIT: Heh... just looked and the very first site I came to has +6. I'll have to order a set. :-)

cheers for the responses guys, i should have checked this thread earlier as i went into calumet and the guy recommended a x8 loupe!

so the general consensus is x4 to prevent the problem of magnifying the grain of the ground glass?

the loupe only cost me £3 or something, so i might give it a go and see if i have any problems.

those reading glasses sound like a fantastic idea!

in reference to the reading glasses, is +4 i the same as x4 magnification?

Some one fill me in. I have been a 4x5 shooter for 20 years. I shoot at F45 or F64. I never use a loupe. All my pictures are in focus. i enlarge up to 40x36 with no problems. Am i missing something ?

Joe; as +4 reading glasses is the diopter. A positive number means you can mage a real image; burn ants/bugs; start a fire with the sun too. A +4 is nominally a 250mm lens; a +1 is a 1000mm lens; a +3 is a 333mm len in focal length. If ones eyes focus ok at infinity; but not close up; a +4 lens (diopter) means your eyes think the book at 250mm away is at infinity; thus it is in focus. These diopter numbers are for dime store reading glasses at Walgreen and Walmart; where reading glasses are positive. In a few cases stores have negative lenses; this is rare in the USA; and more common in other countries. Here I have a full set of diopter lenses in briefcase; like old eye doctors used.
For a handheld magnifer the basis for magnification is abit different; one has the lens or loupe not always at the eye.