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Pawlowski6132
1-Aug-2017, 12:56
So, back to shooting 8x10 after a break. I don't remember it being so hard to focus on the GG. I've used two different types today and I just can't see anything really sharp on the GG.

I don't believe it's a function of the loupe, or my eyesight and I can't believe both GG I used are BOTH crappy (but, I guess it's possible.)

Has anyone else run into this??

thanx as always.

Jac@stafford.net
1-Aug-2017, 13:12
So, back to shooting 8x10 after a break. I don't remember it being so hard to focus on the GG. I've used two different types today and I just can't see anything really sharp on the GG.
I don't believe it's a function of the loupe, or my eyesight and I can't believe both GG I used are BOTH crappy (but, I guess it's possible.)
Has anyone else run into this??
thanx as always.

Yes, when I developed some kind of condition for which my doctor suggested mild boric acid eye washes. Simply, the surface of my eyes clouded with some kind of fluid. I did the treatment, and it went away. In fact, at this moment the clouding is back in a minor way and makes it difficult to see the monitor.

You may also have experienced, hopefully, a transient neural issue. Was the ambient light unusual in any way?

Best of luck!

plaubel
1-Aug-2017, 14:00
My first ideas for troubleshooting:

changing the lens
washing the GG
using a dark cloth
checking for flare/light dropin (seals, bellows).

Instead of a loupe, I feel more comfortable with strong reading glasses.
Maybe you only need some diopter plus, after your break ?

Best,
Ritchie

alkman
1-Aug-2017, 14:09
This might sound odd, but you might want to check that the elements of your loupe are screwed together well. I have a Rodenstock 4x loupe where the elements sometime get a little bit unscrewed with jostling and the like, making it impossible to focus on the GG. Just a thought...

Jac@stafford.net
1-Aug-2017, 14:14
This might sound odd, but you might want to check that the elements of your loupe are screwed together well.

!!! Good Idea !!!

Luis-F-S
1-Aug-2017, 15:46
No I can focus a view camera

Pawlowski6132
1-Aug-2017, 15:55
No I can focus a view camera

So can i. Still having a problem. Thanks for insightful comment though.

John Kasaian
1-Aug-2017, 17:32
What lens is up front?
Racking the bellows out to the equivalent focal length should get you close---could the lens elements be off?
Is the aperture open wide for focusing?
What were you focusing on? You might try using a printed page as a target.

Two23
1-Aug-2017, 18:19
So can i. Still having a problem. Thanks for insightful comment though.


LOL!!!!!!



Kent in SD

Luis-F-S
1-Aug-2017, 19:03
You asked if anyone else "has run into this"; and I answered No! Without looking through your camera/lens, I have no idea what you're doing wrong, because I and thousands of others can focus an 8x10 view camera on the ground glass! I'd start by getting my eyes, glasses, focusing loupe checked. If they're all ok, I'd then try a different lens/camera/ground glass. I don't use a focusing loupe, I use a 5x readers. Those are all the variables, but YOU are going to have to be the one to figure it out. That assumes your equipment is working as designed, but to make a statement that "8x10 Ground Glass Focus is Crap" is garbage in itself.

dasBlute
1-Aug-2017, 20:39
so, what do you mean by "I've used two different types today..."
Are you swapping GGs into a single camera, or are these from two 8x10s
that have worked well in the past?

AtlantaTerry
1-Aug-2017, 22:11
So, back to shooting 8x10 after a break. I don't remember it being so hard to focus on the GG.


Maybe it is time to have your eyes checked by an ophthalmologist.

Vaughn
1-Aug-2017, 22:23
Well, I would suggest having someone else see if they can focus it.

Lachlan 717
2-Aug-2017, 00:07
Start by eliminating variables - starting with the lens.

Was it the same one on both cameras? If so, was it a similar optical result on both cameras? If so, check the lens.

Contrary to the slightly acidic suggestion of Luis-F-S, I would start with the things that you can do for yourself, rather than starting with getting your eyes tested... This approach requires more effort than checking the lens.

Additionally, it seems a strange theory to blame vision/glasses if you haven't had any issues with your vision prior to looking at a ground glass.

Keith Pitman
2-Aug-2017, 03:39
A couple of years ago I was having trouble focusing and finally tied it to a change in my eyeglass prescription. When I refocused my loupe, focusing on the GG got back to normal. Make sure your loupe is focused.

Jerry Bodine
2-Aug-2017, 12:16
I know I've posted this before, but it's been awhile. Decades ago, my backpacking buddy had been complaining about his Linhof trannies not being as sharp as they used to be. I asked him if he'd had his vision checked lately; he said his eyes were fine. Then we were on our way to Wyoming for a vacation trip to the Wind River Wilderness; he was driving and had left his sunglasses in his pack in the back of the car but didn't want to stop to get them, so I offered him my prescription sunglasses and said I wanted to nap anyway. He put them on and was aghast "OMG!! I can see every tree on that ridge. Everything is so SHAAAP" (he was from Boston). When we got back home he had his eyes checked; it turned out we both used the same optometrist to make our glasses, and when I went in to pick up my new lenses, the optometrist started telling me about this guy who ordered BIFOCALS but wanted the close distance part placed in the TOP of the lenses so it'd be more comfortable for him when working under the darkcloth since he had to lean forward to see the groundglass. I said I think I know that guy.

Pawlowski6132
2-Aug-2017, 12:42
Ok. Thanx for the helpful suggestions.

Again, the issue is that the image on the GG doesn't get sharp or appear in focus. At least not to the degree that I would expect.

At 50 years old, my eyes are not good but, I can focus on everything else (books, phone screen, prints, negatives, etc.) and also the ground glass. That's how I know the image on the GG is not sharp. As I rack the bellows in and out, I can see details (say in a tree) begin to come into focus, get to the "most" sharp it gets on the screen and then leave that point and move to out of focus again as I continue to focus the bellows.

I don't think it's the lens. It's a Nikkor 450 M. It works because I can get negatives that are perfectly sharp.

I replaced the ground glass using two different examples - same problem on each.

When I look at the GG just using reading glasses it looks sharp from about 6 or so inches away.

But when I use a higher power loupe, it's impossible to focus critically on a minor detail (say eye lashes for example).

In conclusion, I'm chalking this up to:

1) Quality of the Ground Glass
2) Expectations

I wont continue to worry to much about it. I will continue to feel my way to optimum focus.

Jac@stafford.net
2-Aug-2017, 12:55
I wish you good luck with this issue and hope you share a conclusion if there is one.

I had a loupe that went out of whack due to heat (standing in sunlight too long) and tested it by placing it on my LCD screen laptop. Sure enough it could not possibly resolve. It is more likely a loupe problem rather than your eyes suddenly changing.

Best,
Jac

Colin Graham
2-Aug-2017, 12:56
I've had a similar problem with homemade screens if I grind them with a grit too fine. For me things seems to pop into focus a little easier on a coarser ground glass. But it's also harder to resolve very fine details on a coarser screen, and they are a bit dimmer as well, so it's a trade off.

Bob Salomon
2-Aug-2017, 14:22
Ok. Thanx for the helpful suggestions.

Again, the issue is that the image on the GG doesn't get sharp or appear in focus. At least not to the degree that I would expect.

At 50 years old, my eyes are not good but, I can focus on everything else (books, phone screen, prints, negatives, etc.) and also the ground glass. That's how I know the image on the GG is not sharp. As I rack the bellows in and out, I can see details (say in a tree) begin to come into focus, get to the "most" sharp it gets on the screen and then leave that point and move to out of focus again as I continue to focus the bellows.

I don't think it's the lens. It's a Nikkor 450 M. It works because I can get negatives that are perfectly sharp.

I replaced the ground glass using two different examples - same problem on each.

When I look at the GG just using reading glasses it looks sharp from about 6 or so inches away.

But when I use a higher power loupe, it's impossible to focus critically on a minor detail (say eye lashes for example).

In conclusion, I'm chalking this up to:

1) Quality of the Ground Glass
2) Expectations

I wont continue to worry to much about it. I will continue to feel my way to optimum focus.

Are you using a loupe with a focusing eyepiece or one without? If you are have you adjusted it to be in focus on the grain side of the ground glass? If not, or if your loupe does not have an adjustable eyepiece then your loupe is not focusing on the image plain.

Ari
3-Aug-2017, 07:01
I've had some GGs that did not "snap" into focus because they were coarsely ground for a better aerial view.
The coarse grind shows its shortcomings when a high-powered loupe is used (8x or higher).
Since I use a 10x loupe, I had my existing Gas ground even finer so that the grain was very minuscule.
This gave me a darker GG, i.e., I couldn't see much in the corners from 18 inches away, but focusing with my loupe was great.

Pere Casals
3-Aug-2017, 07:40
So, back to shooting 8x10 after a break. I don't remember it being so hard to focus on the GG. I've used two different types today and I just can't see anything really sharp on the GG.

I don't believe it's a function of the loupe, or my eyesight and I can't believe both GG I used are BOTH crappy (but, I guess it's possible.)

Has anyone else run into this??

thanx as always.


If your loupe is a focusable magnifier, you know... there is a ring to adjust it for your sight and for the GG thickness, if no ring...


My loupe is a cheap one, without a focus ring, so I've to separate it some 2mm from GG to see it sharp, I make contact at one side and I tilt it to separate it from GG. If your loupe is x8 you should see the glass grains, if you don't see the grains then problem is in the loupe, not in the camera lens.


Regards

Bob Salomon
3-Aug-2017, 08:46
It
If your loupe is a focusable magnifier, you know... there is a ring to adjust it for your sight and for the GG thickness, if no ring...


My loupe is a cheap one, without a focus ring, so I've to separate it some 2mm from GG to see it sharp, I make contact at one side and I tilt it to separate it from GG. If your loupe is x8 you should see the glass grains, if you don't see the grains then problem is in the loupe, not in the camera lens.


Regards

A 4x loupe will easily show the gg grain if the loupe is properly adjusted to do so.

Pere Casals
3-Aug-2017, 09:12
It

A 4x loupe will easily show the gg grain if the loupe is properly adjusted to do so.

Hello Bob, thanks for pointing it. My Cambo GGs are coarser than my Sinar ones, I was not sure that an smooth GG could show grains with x4, in special with f/9 glasses or low light. I've ben focusing with x8, but as I get more experience I perhaps consider x4 a better choice for most situations.

Old_Dick
3-Aug-2017, 09:15
How about a fresnel GG?

Bob Salomon
3-Aug-2017, 10:47
Hello Bob, thanks for pointing it. My Cambo GGs are coarser than my Sinar ones, I was not sure that an smooth GG could show grains with x4, in special with f/9 glasses or low light. I've ben focusing with x8, but as I get more experience I perhaps consider x4 a better choice for most situations.

It doesn't matter what speed lens you are using. You focus the eyepiece of the loupe on the grain of the gg, best and easiest to do with no lens on the camera. Once adjusted it stays adjusted unless you change the gg or Fresnel. Nothing to do with your lens.

Pere Casals
3-Aug-2017, 11:28
best and easiest to do with no lens on the camera. Once adjusted it stays adjusted unless you change the gg or Fresnel.

thanks for the tip !