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tron_
8-Oct-2014, 12:36
Hello,

My name is Suraj and I'm a 25 year old photographer from Detroit Mi. I have been shooting film for about 6 years now and got into large format photography last winter after picking up a Toyo 45CX with a Fujinon 135mm lens.

I have had focusing problems and was wondering if someone here could give me some tips. Right now I am using a Nikkor 50mm 1.8 lens as a loupe. I place the lens filter threads on the ground glass and look through the lens (from the lens mount side) to check focus. From here I use the fine focus on the front standard to make sure everything looks good.

This hasn't been working well and my photos are many times out of focus.

Do you guys know what I am doing wrong? I've heard of people taking the lens off the camera to focus, some people say using a reverse lens like mine will result in the photograph being out of focus by the thickness of the ground glass since the image is made on the grain side of the glass, etc.

Any tips on what I can do to remedy the problem?

Bob Salomon
8-Oct-2014, 12:59
First make sure that your ground glass is properly installed and in proper register. Then return the lens to the camera and get a proper, focusing eyepiece loupe and adjust its focus so it is focused on the grain side of the ground glass.

tron_
8-Oct-2014, 13:15
First make sure that your ground glass is properly installed and in proper register. Then return the lens to the camera and get a proper, focusing eyepiece loupe and adjust its focus so it is focused on the grain side of the ground glass.

Thank you very much for the reply. So the loupe will allow me to adjust it's focus such that it will focus on the grain side of the gg?

Also is there any way I can get by with my current setup in the mean time?

Bob Salomon
8-Oct-2014, 13:29
Thank you very much for the reply. So the loupe will allow me to adjust it's focus such that it will focus on the grain side of the gg?

Also is there any way I can get by with my current setup in the mean time?

Not if you want to eliminate the problems that you are currently having.

BrianShaw
8-Oct-2014, 13:44
Try focusing without a loupe. You may be surprised at how well it works. (or is that, how GOOD it works?) Some folks report good success using drug store magnifying spectacles.

cowanw
8-Oct-2014, 14:10
I don't think your using the lens as a loupe will be the problem. You cannot make a Ground glass that is out of focus come into focus with a loupe. Incorrect use of a loupe will make a out of focus Ground Glass even more blurry.
Eyeball your focus on a ruler laid out long ways as a subject; write down the number you are focussed on. When that neg is developed you can measure how far you are out by looking at what is the best focus on the ruler.
If nothing is in focus you have a bad lens. If you are out by x amount the GG and your film are a different distances or you are misfocussing.
Remember you are looking for the best focus of your subject on the GG not necessarily perfect focus. After all your eyes may be bad too.

Jon Shiu
8-Oct-2014, 14:31
Your problem is due to placing the lens against the ground glass, not any "calibration" errors. First practice with the magnifier/lens by holding it a few inches from your eye and then moving it close to some print like a newspaper or something until in sharp focus. Note that the lens will be not in contact with the newspaper when in focus! Now that you have a feel for how far away from the ground glass to be it should be easy to use the "loupe" lens.

Jon

Neal Chaves
8-Oct-2014, 15:52
When using a lens like that for a loupe, and I have several surplus copier lenses for that purpose, first focus the loupe on the grain of the ground glass first and hold it there. Then focus the image on the ground glass.

tron_
8-Oct-2014, 21:41
Unfortunately I think you guys are correct saying using my reversed lens may be causing my focusing error. I did some testing today and wound up with blurry negatives again, very disappointing.

I decided I should just get a dedicated loupe. Are these steps correct for "calibrating" the loupe?

1. Remove lensboard
2. Put loupe against ground glass
3. Adjust the loupe so the grain of the ground glass is focused

Also, can someone recommend a loupe that is <$75? I was looking at the Toyo 3.6x loupe but it appears it is not made anymore.

Respectfully,
Suraj

Alan Gales
8-Oct-2014, 22:17
http://www.bhphotovideo.com/c/product/40719-REG/Peak_1302038_4x_Loupe.html

A little above your price range. You can check Ebay for a used loupe in your price range or buy some new reader glasses at your local drug store.

Doremus Scudder
9-Oct-2014, 03:26
There's no great mystery to this. Whatever you use to magnify the image with needs to focus on the plane where the image is projected, and that is the frosted side of the ground glass.

So, try it out with several things. Remove the lensboard from you camera and then, by changing position of whatever you use to magnify with, position it so the frosted grain of the ground glass is in focus. That then is the correct position, i.e., distance from the ground glass, for that magnifier. Your Nikkor lens should work too (it just seems rather bulky to use as a focusing aid, and a bit risky too, since they are easy to drop...).

Sure, a nice loupe is great to have. That said, I use regular, rather cheap 8x or 10x loupes intended for viewing 35mm slides (Peak/Nikon, etc. are good quality and not too expensive). For my travel kit in Europe, I have a nifty 8x flat magnifying loupe that slides into it's own plastic cover, really just a small single-lens magnifier. It works great and is very small. A Sherlock-Holmes-style magnifying glass will work too. Just focus on the right area of the ground glass.

FWIW, I use 3-4 diopter reading glasses for rough focusing and then use the loupe to finely focus the areas I've chosen as focus points.

Best,

Doremus

Struan Gray
9-Oct-2014, 03:45
Your eyes are too young.

I use a 50 mm lens as a loupe too (although it's one from a Pentax 110, which makes it a more handy size). 'Real' loupes have a skirt or a spacer (often adjustable) which puts the loupe at the right distance from the ground glass when the skirt comes into contact with it. Lenses held freehand don't have this, and unless you are careful, they can drift in and out with respect to the ground glass.

Ground glass scatters some, but not all of the light. If you have eyes which easily accomodate (young ones, under 35 or so) it is very easy to end up with the lens at the wrong height above the ground glass, and your eye focussed on the unscattered light forming an image somewhere behind or in front of the ground surface of the ground glass. You then naturally have a focussing error, because the film does not end up in the right place.

The trick, as Neal said, is to make sure your lens is focussed on the ground glass plane before you start trying to focus the projected image. You can move the lens back and forth until the texture of the glass is as clear as possible, or, if your ground glass has markings on it, focus on those. Some people add a mark with a soft pencil for precisely this purpose. Once you are sure that the lens/loupe is at the right place, then start to adjust focus on the camera *whilst keeping the lens the same distance from the ground glass*.

It sounds like a hassle, but it's really not. I just rest the edge of the hand holding the lens/loupe on the ground glass and hold it still once I am sure I am focussed on the right place. I often use rear focussing so as not to move the lens, and it's not at all difficult to keep my hand still enough.

tron_
9-Oct-2014, 08:41
First off, thank you to everyone who posted in this thread. I very much appreciate you guys taking the time to answer a question which might seem pretty stupid to a lot of the experienced guys on here. But I am excited to be shooting large format and can't thank you guys enough.

So you guys are saying that since a loupe has a skirt on it that positions it off the ground glass, it will focus on the grain side of the ground glass? And by having my Nikkor lens set against the back of the ground glass I am focusing on the wrong side of the ground glass. I will try holding the lens off the ground glass today to reinforce the concept but feel like purchasing a loupe will be a good idea for me.

Right now I'm leaning towards a square loupe to check corner focus a little easier. The Peak 4x one looks very nice, I'll poke around online and see what will work best. If you guys have any further recommendations I would be really grateful!

Respectfully,
Suraj

Luis-F-S
9-Oct-2014, 09:22
You could just get a strong pair of reading glasses. I had a 5x pair made around 30 years ago which is what I still use............L

tron_
9-Oct-2014, 09:28
I thought about it and read they work beautifully but considering I already wear glasses it would feel a little cumbersome having to change between glasses in the field! Also I think a loupe might be handy for inspecting my 35mm and 120 negatives :)

Jac@stafford.net
9-Oct-2014, 09:43
Also, can someone recommend a loupe that is <$75? I was looking at the Toyo 3.6x loupe but it appears it is not made anymore.

Don't laugh, but for years I used one like this (http://www.amazon.com/Dot-Line-Corp-DLC-Loupe/dp/B002R8CYY8/ref=sr_1_1?ie=UTF8&qid=1412872897&sr=8-1&keywords=8x+loupe). $12 USD! However, I used inverted and adjusted distance from the ground glass as necessary.

Used it in the normal manner for examining negatives on the light box.
.

djdister
9-Oct-2014, 10:27
Don't laugh, but for years I used one like this (http://www.amazon.com/Dot-Line-Corp-DLC-Loupe/dp/B002R8CYY8/ref=sr_1_1?ie=UTF8&qid=1412872897&sr=8-1&keywords=8x+loupe). $12 USD! However, I used inverted and adjusted distance from the ground glass as necessary.

Used it in the normal manner for examining negatives on the light box.
.

Ah yes, the classic loupe. Sometimes the simple things work best...

ic-racer
9-Oct-2014, 12:27
An out of focus loupe will not make an out of focus ground glass image in focus. Check proper film loading, proper film holder insertion, rule out camera movement, etc, etc...

Jac@stafford.net
9-Oct-2014, 13:02
An out of focus loupe will not make an out of focus ground glass image in focus.

Yes, that has been my experience, but the point of using a camera lens confused me. Could it be that the OP was focusing on an aerial image instead of the GG?
.

Struan Gray
9-Oct-2014, 14:26
Focussing on the aerial image is what my long-winded post was meant to be about. It's surprisingly easy to do, especially if most of the detail lies in one plane - your eyes accommodate and 'see' the aerial in-focus image without you noticing that the ground glass texture has become unsharp. With dense detail at lots of different distances, there is less tendency for your eye to jump 'off' the ground glass.

Suraj, try putting a small pencil mark on the ground glass. Focus on that with the loupe, and keep it in focus as you then focus the image. Go shopping only if that fails.

brucetaylor
9-Oct-2014, 14:31
What Struan says. If you do that and you still have focus problems you have other issues.

Jac@stafford.net
9-Oct-2014, 15:21
Thank you for that. Such is one issue, besides my uncorrectable vision I choose 4X max for a loupe now.

Ari
9-Oct-2014, 17:01
Or try this one: http://www.bhphotovideo.com/c/product/40687-REG/Peak_1301960_5x_Loupe.html

No focusing required.
I used it for a few years without problems.

Keith Fleming
9-Oct-2014, 18:44
Struan's recommendation to put a pencil mark on the ground glass is great advice. For me, the pencil mark allows me to check my focusing loupe and make sure it is in focus.

Keith

Andrea Gazzoni
9-Oct-2014, 23:57
pencil mark has to be on the internal side of the gg, right? I mean the side that faces the lens rear element

Struan Gray
10-Oct-2014, 00:14
It needs to be on the focussing surface - the ground, partially opaque surface of the ground glass. On most cameras that is the side facing the lens.

hoffner
10-Oct-2014, 04:35
Or try this one: http://www.bhphotovideo.com/c/product/40687-REG/Peak_1301960_5x_Loupe.html

No focusing required.
I used it for a few years without problems.

No focusing is required for viewing slides on a light box (that's what this loupe is for). On a gg the frosted side (where you want the focus to be) is several mm away from that point!

Jim Jones
10-Oct-2014, 04:44
25-year-old eyes should focus fairly well, if not perfectly, on a ground glass without a loupe. When one wears glasses that correct for much astigmatism, replacing them with strong reading glasses might make accurate focusing difficult. In this case, a good loupe is certainly better. If it is accurately focused on the ground surface of the ground glass, one possible cause of unsharp images on film is eliminated. Having to maintain that accurate focus by hand is less convenient, but can otherwise work as well. Large format photography is not about convenience; it is all about image quality. In many decades of large format photography, I've never had a really good loupe.

Camera problems should be checked as Bill describes in post #6 and in more detail elsewhere. Sometimes the ground glass has been removed and improperly reinstalled. Also, focus can shift if the camera adjustments are not securely locked down.

greenbank
10-Oct-2014, 05:48
If you want a cheap loupe to start with, try an electronics store (Maplins in the UK has a 6x loupe for 8, or about $12) or even a haberdashery. Look for something called a "linen tester" - clothiers use them to check thread-per-inch counts, and electronics people use them to examine tiny components and circuit-boards. Mine - made in China - has a thin square frame, so it can get into the corners of the ground glass; and it folds down neatly into a flat wallet. The frame sits on the surface at the focal distance of its lens, so it's actually checking the focus of the rear (outside, flat) face of the GG; but for 8 that's an adjustment I'm prepared to put up with.

tron_
10-Oct-2014, 11:17
Again, thank you all again for the kind replies. I will try out the pencil mark trick tonight. I'll put a small pencil mark on the side of the ground glass facing the rear lens element and focus as I usually do and see if the pencil mark is also in focus.

I'll go ahead and include some photos of the process so we can ensure I am installing the ground glass correctly!

Respectfully,
Suraj

Andrew O'Neill
10-Oct-2014, 13:52
Either by a loupe or pick up some cheap reading glasses from the drugstore. I even used a junky pair from the dollar store that worked very well.

tron_
1-Dec-2014, 23:44
Hey guys, thought I would update this thread as to what was happening.

I was planning to go out and use my new Peak loupe and spent some time practicing the sequence of shooting with the Toyo. I realized (not for the first time haha) that I'm a huge idiot and I was loading the film from the wrong side. This caused the film to load crooked so it was not parallel to the standards.

I rotated the film holder part of the camera (the name escapes me) and went out to shoot.

It was super dark and I was rushed but my focus appears to be much better! Ilford Delta 100 pushed to 800 and developed in a 1:1 dilution of Xtol for 16:45.

Again my focus isn't perfect but I'm chalking that up to it being super dark. I was having a hard time focusing.

https://farm8.staticflickr.com/7546/15927909042_394e193b18_o.jpg

djdister
2-Dec-2014, 05:34
If you are having really basic problems like focus or exposure, you should do some shooting in clear daylight, not under "super dark" conditions. Start with a normal shooting scenario of a sunny day, and get your focusing and exposing down under ideal conditions before shooting under challenging conditions.

And one more note about focusing with a loupe (or whatever) pressed against the groundglass - just make sure you aren't pressing the rear standard forward with the loupe to focus. If you are pressing too hard, once you release the pressure on the groundglass, the rear standard will relax back to the shooting position which is no longer in the same plane of focus.

BrianShaw
2-Dec-2014, 07:18
... +1

tron_
2-Dec-2014, 11:07
If you are having really basic problems like focus or exposure, you should do some shooting in clear daylight, not under "super dark" conditions. Start with a normal shooting scenario of a sunny day, and get your focusing and exposing down under ideal conditions before shooting under challenging conditions.

And one more note about focusing with a loupe (or whatever) pressed against the groundglass - just make sure you aren't pressing the rear standard forward with the loupe to focus. If you are pressing too hard, once you release the pressure on the groundglass, the rear standard will relax back to the shooting position which is no longer in the same plane of focus.

I'm aware that shooting in low light is not idea.. We were walking around the woods when the sun began to go down so I had to improvise and push my film while making a longer exposure. Not my first time shooting film in low light so I'm aware of things like reciprocity. It just made focusing a bit harder but I was confident I fixed the problem by loading my film correctly.

The point about pushing against the rear standard is a good tip, definitely something to keep in mind.

Tracy Storer
2-Dec-2014, 11:35
If no one else has suggested it yet, make a small "X" on the textured side of your ground glass, making sure it is properly installed, frosted side towards the inside of the camera and towards the shooting lens. Adjust your "loupe" or whatever you're using, so that the "X" is sharply focused, this may just be holding your reversed lens the right distance from the GG, THEN adjust the camera to focus the image on the GG.

Failing that, I have been using +3 diopter reading glasses for focusing my 8x10 for about five years with no problems, though I find smaller formats a little more challenging. (I'm 50, so my eyesight is not good for close work unassisted anymore)

Liquid Artist
3-Dec-2014, 09:16
Personally I have problems with reading glasses since both my eyes are different strengths now. It will look fine with 1 eye, but blurred with the other. I am hoping on getting a prescription set soon to cure this.

However I've used 35mm camera lenses, hardware store loupes, simple dollar store magnifying glasses, and even elements removed from a couple lousy 35mm lenses I had. They all work, and I keep at least 2 choices in every camera bag.

What I usually do now is just start out under the darkcloth usually a foot away from the ground glass and bring the scene into view using just my eyes. I then take out the dollar store magnifying glass, until I see sharp details, and then use my dedicated (Zeiss) loupe for the finishing touches.

Oh, one more thing I haven't seen mentioned.
The wider the lens, the harder it is to focus. I've been shooting LF for around 2 years now, and still have issues focusing with my 90mm.
If your using a 135mm or longer lens this won't be your issue, if your using a shorter lens it may be.

Timothy Blomquist
3-Dec-2014, 20:18
I've been shooting large format since 1977, before I had to wear prescription glasses. These days I have to use my glasses while doing general course focus, then remove them to use the focusing loupe for fine focus. I use a loupe with a diopter adjustment and sometimes it will shift, resulting in not having to place the loupe against the ground glass to to obtain critical focus. This is unnerving but still works, and saves having the ground glass or Fresnel getting scratched by contact with the loupe.

Having done this for 37 years, all I can say is practice, practice, practice. Set the camera up, get a chair to sit on, and play with focusing the camera with no movements. Perfect that, then practice with simple front tilts. Perfect that then play with back tilts. Get good with that then learn simple front swings, etc, etc. Do this before you ever buy your first box of sheet film. The stuff is too expensive to waste while learning camera manipulation.

Do the same type of practice with hand held light meters. I use two most of the time. An incident Gossen Luna pro digital and a Pentax digital spot meter. I shoot chromes most of the time so I use a version of the zone system by exposing for the highlights. I am limited to zone VII 1/2 for the highlights and I scan the scene for objects I wish to place at that level, or if they naturally fall at that level. If you're still learning, practice the exposure with the hand held meter then take a digital SLR and input the same exposure info with that camera's manual setting and see what it looks like.

Dan Dozer
4-Dec-2014, 16:41
Rather than a loupe, you can get very inexpensive magnification type of glasses at your local pharmacy that I've heard work. However, I wear glasses and constantly switching pairs around was not a good option for me. My optometrist got me a pair of flip up magnifiers (about 4 - 5 x) that I just clip on my glasses and flip down when focusing on the ground glass. They work extremely well and focus with my eyes about 4" from the back of the ground glass (perfect when under the focusing cloth). One problem is that they don't line up with the bifocal lenses in my normal glasses, so I need to use them with non-bifocal glasses.