4x5 loupe

[John DeFazio]

I have read an article re: making a home made loupe that has fantastic results, but I do not understand if I'm to use one lens or if two are needed. If anyone is familiar with such a home made loupe, please update me on its constuction. Thank you, John D. jdefazio6076@gmail.com

[Leigh]

At a minimum I would use an achromat (cemented doublet).
A single lens (like a magnifying glass) would yield pretty poor performance.

- Leigh

[Bob Salomon]

Do you mean a loupe to see the entire gg at one time or part of the gg? If the entire gg it will not be strong enough to see critical detail. If part of the gg why waste the time and money? There are lots of very high quality 4, 5, 6 and 7x loupes available. And many are fully coated, if not multi coated and some are aspheric.

[Drew Bedo]

There aught to be a lot of film-SLR lenses available for pennies on the pound. An f/2 50mm should be well corrected enough to use as a loup.

But, why build a loup?

I have at times used an "Optivisor" jeweler's head set. For more mag put on reading glases under the heqd set.


Years ago, I talked my optomitrist into perscribing a set of high magnification "reading" glasses. Don't remember the mag factor, but the working distance was ~4 inches. Worked well and corrected for my vision too.

[Former Member 27732]

What Drew said....
I use a single pair of x6 readers, freeing up both hands to do all the camera tweaking stuff, while I'm watching the GG. Couldn't be easier.
/Frank

[Leigh]

I have at times used an "Optivisor" jeweler's head set. For more mag put on reading glases under the heqd set.
The Opti-Visor is an excellent product. The lenses are interchangeable without tools, available up to 10x IIRC.

- Leigh

[Dan Dozer]

What Drew said....
I use a single pair of x6 readers, freeing up both hands to do all the camera tweaking stuff, while I'm watching the GG. Couldn't be easier.
/Frank

I do this too. I got a pair of clip on/flip ups that I use on my regular glasses. Only issue is that they don't work with bi-focals (lenses in the two pairs don't line up) so I use my distance viewing lenses for camera work.

[StoneNYC]

I've discovered I need a loupe too, mostly at night time when focusing for long exposures in very little light (sometimes absent of moonlight).

Now I have very good night vision and I have been able to see the ground glass and an image very faint, but enough to tell when I put it from in focus to out of focus, but not PERFECT focus simply because I have bad close vision now. So what loupe would not lower the light throughput since its already so faint... I've seen some 6x and 8x sell on ebay from china for $75 is this good enough? Or should I get something more brand named?

It's a light transmission issue, I don't want the image even dimmer than it is if possible.

I feel like a home made or 50mm reversed would introduce light loss.

Or am I wrong?

[AtlantaTerry]

I buy cheap reading glasses from the dollar store in my view camera kit.

Made in China they are ... USD $1.

[StoneNYC]

I'm testing out a cambo 7x loupe, it's ok but I wish it were longer so my face and hands were father from the ground glass.

We'll see :) I certainly wouldn't want any less than 7x

[Ian Gordon Bilson]

You could consider a cheap laser pointer. It is pretty hard to mis-focus on that red dot.

[StoneNYC]

You could consider a cheap laser pointer. It is pretty hard to mis-focus on that red dot.

Huh? I'm confused please elaborate, I'm not familiar with this technique.

[AtlantaTerry]

When working in low light you aim a laser pointer at the subject from the camera position. The red dot shows brightly on the ground glass. Of course, if people are involved you never want to shine a laser of any kind into their eyes.

When I am working on a movie as director of photography or cinematographer we use a similar technique in low light. I have an assistant stand next to the actor and holding a flashlight, aim it back toward my camera. It is quite easy to focus on the spot of light. The actor will be in focus until they move.

[StoneNYC]

When working in low light you aim a laser pointer at the subject from the camera position. The red dot shows brightly on the ground glass. Of course, if people are involved you never want to shine a laser of any kind into their eyes.

When I am working on a movie as director of photography or cinematographer we use a similar technique in low light. I have an assistant stand next to the actor and holding a flashlight, aim it back toward my camera. It is quite easy to focus on the spot of light. The actor will be in focus until they move.

You must not be on movies very often, they do use lasers but they are lazer measures that measure the distance till the laser stops, I work on movies so I'm always putting my hand next to my eyeline so they can measure (I'm a stand in often).

Either way that doesn't help me when I'm focussing on an island off the coast...

[AA+]

I got my eye doctor to give me my eyeglass prescriptions with +5 diopters each eye. This works well for the ground glass, but walking around is a problem with such blurry far vision.

Best wishes --- Allen

[AtlantaTerry]

Stone,

My IMDB: www.imdb.com/name/nm1669504/board/thread/100119963

[Racer X 69]

But, why build a loup?

I have at times used an "Optivisor" jeweler's head set. For more mag put on reading glases under the heqd set.

This is an excellent idea. Thanks Drew!