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axs810
18-Jun-2015, 02:17
Out of the various types of ground glass YOU might have tried what is the absolute best ground glass and/or fresnel available today?


I bought a Steve Hopf's borosilicate ground glass to see what it would be like on my Speed Graphic, but since the fresnel needs to be in between the lens and ground glass so I feel as though I'm not getting the full potential? :confused: (if that makes sense) It's still a heck of a lot better than it was but I guess I was just expecting more of a "wow" factor on the brightness scale

Phil Hudson
18-Jun-2015, 03:48
Fo general use I'm very happy with my Beattie Intenscreen. The cover glass coatings scratch easily but they are replaceable.

To some extent the "right" glass for you might depend on the strength of lupe that you are using - at least that's what I found.

axs810
18-Jun-2015, 04:31
I'm using an x8 lupe which I believe works well for me...only reason I ask about the "best ground glass" is because the ground glass on my Wehman 8x10 seems soft on the edges. Meaning when something is in focus it doesn't "pop" into focus really well like previous cameras I have owned. If that makes any sense?

dave_whatever
18-Jun-2015, 04:31
Maxwell screens are great, but despite the hyperbole surrounding them I do think that they are too expensive for what you get.

I used a Hopf plain ground glass for a while which was nice, but for wides I still needed to find a decent fresnel. For long lens work this could be all you ever need.

The ebony combo gg/fresnel I found great for general use. Add to this their wide angle fresnel and you have an unbelievably bright and even view, right into the corners, on lenses around 90mm and wider, although goes weird with big rise/fall, need to move your head around a bit.

I've heard good things about the Yanke eBay combo gg/fresnel screens to. Should be very similar to the Ebony screens.

axs810
18-Jun-2015, 04:36
I haven't seen ebony gg/fresnel for sale...would you mind directing me to a link so I can check it out?

dave_whatever
18-Jun-2015, 05:32
I haven't seen ebony gg/fresnel for sale...would you mind directing me to a link so I can check it out?

http://www.robertwhite.co.uk/ebony-5x4-focusing-screen-cover-glass.html

Jac@stafford.net
18-Jun-2015, 06:19
http://www.robertwhite.co.uk/ebony-5x4-focusing-screen-cover-glass.html

From Robert White co. "The unique bright screen effect combines properties of a fresnel with a focusing screen in one piece."

Now that is interesting! How do they combine a fresnel into the ground glass? I ask because I stopped trying to use a fresnel long ago when the ones I got were flexible, and couldn't decide upon what side of the glass it should go (I put it on lens side).

axs810 - the GG in your new-to-you Technika is my favorite. YMMV.

Ari
18-Jun-2015, 06:20
I think it depends on the format and lenses used.
For 4x5, the best I ever used was the Wista screen on my RF and SP cameras (long gone).
I've been through a number of screens for 8x10, the Yanke was the best right out of the box for normal and longer lenses.
Since I use a 10x loupe, I found that commercially-available screens were too coarse for 10x focusing, so I bought a plain GG off eBay, and had a friend going it down further.
The result is a very fine-grained screen, perfect for 10x focusing, but it's darker for aerial viewing than a Yanke.
I have yet to try a Maxwell screen.

Jac@stafford.net
18-Jun-2015, 07:04
For 8x10 the best I've found were made by Kodak, packed ten to the box.
I'm down to seven. Don't know if they are still available, but if you find
one, try it.

OK, posting too much. I'll stop for the day.

dave_whatever
18-Jun-2015, 07:16
How do they combine a fresnel into the ground glass?

I've no idea how they are manufactured but the Ebony and Maxwell type screens are a sheet of plastic, with the "ground" side facing the lens, and a set of fresnel ridges on the other side, presumably moulded in. Hence they come with a clear cover glass so your loupe doesn't trash the relatively delicate fresnel ridges.

EdSawyer
18-Jun-2015, 11:20
The Canham gg/fresnel is the same design and manufacturer I believe as the Maxwell and Ebony ones.

Drew Wiley
18-Jun-2015, 11:44
As much as I praise Ebony cameras in general, the first thing I did was get rid of that wretched GG/fresnel sandwich. It easily gets condensation and fogs up in between. I replaced it with a Satin Snow GG, though a Sinar GG nearly fits, with just a bit of resizing.

cdholden
18-Jun-2015, 16:21
I replaced it with a Satin Snow GG...

Are those still available? I'd like to get a few more for 8x10 and 5x7.

Drew Wiley
18-Jun-2015, 16:26
He's out of business, but somebody else is making something analogous I think, and there are some past threads telling you how to properly grind your own. Somebody will chime in, or try a thread search. They were the best GG's I've ever had, and ironically, the least expensive.

Bob Salomon
18-Jun-2015, 16:44
From Robert White co. "The unique bright screen effect combines properties of a fresnel with a focusing screen in one piece."

Now that is interesting! How do they combine a fresnel into the ground glass? I ask because I stopped trying to use a fresnel long ago when the ones I got were flexible, and couldn't decide upon what side of the glass it should go (I put it on lens side).

axs810 - the GG in your new-to-you Technika is my favorite. YMMV.

Old technology that has been available for decades. Among other screens both the Linhof Super Screen and the Beattie Screens used this technology. For these two the largest Fresnel screen manufacturer in the world made a frosted acrylic screen with Fresnel grooves on one side and a smooth, frosted surface on the other side. The plain, smooth, plain side was the focusing side and faced the lens. The grooved Fresnel side faced the user. In the case of the Super Screen a choice of a grid or a plain glass plate was offered to add protection to the grooved Fresnel side.
The Minolta designed Acute Matte screen which was also sold by Hasselblad, Rollei and, most recently, Linhof, was easily the brightest and most evenly illuminated focusing screen but it was never made in 45 and larger sizes and would be prohibitively expensive if it would have been available. Probably costing more then most 45 camera and lens combinations.

Tim Meisburger
18-Jun-2015, 18:14
The Maxwell that came on my Ebony is by far the nicest screen I've ever used, and much brighter than the plain ground glass on my Ikeda. I also have the original Ebony screen, but have never mounted it. I might try it sometime on the Ikeda, then I can test side by side.

BrianShaw
18-Jun-2015, 18:50
He's out of business, but somebody else is making something analogous I think, and there are some past threads telling you how to properly grind your own. Somebody will chime in, or try a thread search. They were the best GG's I've ever had, and ironically, the least expensive.

Steve Hopf is who you are thinking about.

DG 3313
18-Jun-2015, 19:05
I picked up an 8x10 GG from Steve Hopf Feb 5, 2015. I am very happy with it.....


Steve Hopf is who you are thinking about.

axs810
18-Jun-2015, 20:08
DG 3313 - Are you just using the Steve Hopf GG or are you using it in combination with a fresnel? I bought a borosilicate GG from Steve Hopf for my speed graphic and while it is good it's not the best I've used. Most likely the fresnel before the GG is darkening the view slightly...I used to have a different speed graphic with a GG that was plastic like a fresnel but just one solid piece and that was SUPER bright. As in bright enough to be able to focus in lighting that meters f.1.4-2.8

Wayne
18-Jun-2015, 20:35
This thread is kinda confusing. Use this, use that, no this here is best. Maxwell is out of my price range so that's one choice I don't have to make. But I'd like to get something reasonably priced that works for my 8x10 Ansco. All of my 8x10 lenses are f9 or worse, I like to work fairly close, and I don't want to fork out even $150-$250 for something that isn't comparatively brilliant.

axs810
18-Jun-2015, 20:40
^^^I'd like to find something reasonably priced for 8x10 too...it's hard to come by. The cheapest I've found so far (with the best quality) is Steve Hopf's borosilicate. But I feel like there has to be other options that are just as good but slightly cheaper?

Randy Moe
18-Jun-2015, 21:01
Make your own. I do.

I prefer to, as it's so cheap and my vision is only good 2 inches from GG, so I don't use loupes.They don't improve my view.

Over at APUG are great instructions for making a GG. I use small framing glass from Home Despot, which is sized perfectly for 8x10 and 11x14. $2-3 and some grit. Takes 2 hours, while you watch a movie.

Maybe not THE absolute best, but it sure feels great to DIY and SEE how good it is for you. For me, it is my personal best, and that is all that counts. ymmv

fuegocito
18-Jun-2015, 21:14
On 4x5 the best I have seen is Beattie Intense screen and Maxwell. On 810 my favorite is Boss screen. Of all the other fresnel glass I found the bright center/dark corner to be annoying, I almost rather stick with regular ground glass for a truer representation of the scene. These day I care a lot less of about the "best GG" as seemingly most regular will do the job nicely.

jose angel
19-Jun-2015, 01:07
I'm using an x8 lupe which I believe works well for me...only reason I ask about the "best ground glass" is because the ground glass on my Wehman 8x10 seems soft on the edges. Meaning when something is in focus it doesn't "pop" into focus really well like previous cameras I have owned. If that makes any sense?
An 8x loupe seem too much magnification to me. Personally, I use to prefer 4x, 6x at the most.
But I also wonder if it makes sense. Maybe lens` field curvature or edge softness is what makes that softer edges. A "better" screen doesn`t fix it. Also, If you use a "straight view" loupe, things become a bit more difficult towards the edges; a tilting loupe is a nice accessory to have in this respect.
Have you checked it with other lenses? I may be wrong, but I think that with a thin-grittted GG you should have no other problems that even illumination for easy viewing (hot spot). I by far prefer to use a "nude" GG for the finest focusing, and if so, to have a "cheap", thin plastic removable fresnel to check composition.
Notice that fresnels are lenses, they have to be made for different focal length ranges and formats, so one cannot fit all.
My experience with bright screens (like the one mentioned above) has been not that great; they are certainly brighter and *easier to focus* with the naked eye (big "focus pop"), but also tend to be bent along the years, and the grit is much coarser under the loupe.

BTW, it`s not that hard to get used to a "naked" GG. After using a bright screen it looks like there isn`t any other way to go... it will take a little time to work without them, but at the end, I found that nothing like a good, thin gritted plain GG.
(Dedicated press or technical cameras are another topic, the fresnel-in-front configuration of my Technika works like by charm).

axs810
19-Jun-2015, 01:57
Yeah I've tried other lenses on my Wehman 8x10. I've tried a 210mm, 300mm, and 420mm. I think the problem isn't with my loupe but maybe the thickness of the ground glass? The ground glass on my Wehman is very thick...like the width of a q-tip. My other ground glass + fresnel that "popped" things into focus was 1/3 of the thickness.

AtlantaTerry
19-Jun-2015, 02:22
If one wants to be very technical, a Fresnel needs to be made to match each focal length lens.

In other words, a Fresnel that is made to work with your wide angle lens will not be the best one to use with a telephoto.

jose angel
19-Jun-2015, 02:46
Axs810, it`s not the thickness of the glass, but the "roughness" of the surface.
I think coarser surfaces have more "pop" than softer surfaces. They are also slightly brighter. Obviously, fresnel brightness help to perceive that "pop". Without them, and specially the wider the lens, the more obvious "hot spot".
Maybe your Wehman have the "typical" simple GG, finely gritted, quite the opposite to that bright (fresnel+coarse GG) acrylic (plastic) screens.
I`d say you cannot expect to have the same brightness and evenness as on smaller format cameras. We LF users have to live with it.
Personally, I think the best solution could be to buy ($$$) a well proven GG and detachable fresnel form a "modern" system, say Sinar ones (don`t know Linhof), and to adapt it if possible, but I`d not be surprised if you don`t find a difference with the one you are already using. As mentioned, I have almost all my cameras with the original glass screens, they use to be medium to fine grained surfaces. The only permanently attached fresnel I have is the one on my Technika (very old and calibrated one in front of a fine etched GG) which I love. All the other bright screens I have are on the closet.
Funny, my favorite screen these days is a darker, softer simple GG made on a very thin glass that I can use even with a 8x loupe... don`t ask me why. Maybe it gives me the feel of an "extreme" focus accuracy level.
As usual, one or another choice implies a compromise, each design have its own drawbacks and advantages. There are no "best" focusing screen.

axs810
19-Jun-2015, 02:50
Alright I think I get it now

Wayne
19-Jun-2015, 05:54
I'd be happy to try it but can this really compete with the commercial options in terms of brightness?


Make your own. I do.

I prefer to, as it's so cheap and my vision is only good 2 inches from GG, so I don't use loupes.They don't improve my view.

Over at APUG are great instructions for making a GG. I use small framing glass from Home Despot, which is sized perfectly for 8x10 and 11x14. $2-3 and some grit. Takes 2 hours, while you watch a movie.

Maybe not THE absolute best, but it sure feels great to DIY and SEE how good it is for you. For me, it is my personal best, and that is all that counts. ymmv

Ari
19-Jun-2015, 06:08
There seems to be a trade-off with most screens: either you get a bright screen with coarse focusing, or you get a dark(er) screen that is capable of fine focusing.
Perhaps the Maxwell offers both advantages, I don't know.
I do know that my brightest screens were also the most difficult to focus using a strong loupe (8x-10x). For me, using a weaker loupe sometimes resulted in missed focus.

IanG
19-Jun-2015, 06:13
This thread is kinda confusing. Use this, use that, no this here is best. Maxwell is out of my price range so that's one choice I don't have to make. But I'd like to get something reasonably priced that works for my 8x10 Ansco. All of my 8x10 lenses are f9 or worse, I like to work fairly close, and I don't want to fork out even $150-$250 for something that isn't comparatively brilliant.


I make my own screens and make around 100 a year for others, I ca focus my f16 151mm WA (a Ross Protar) indoors in tungsten room lighting quite easily on my 2nd Agfa Ansco 10x8. Same goes for my B&L f9 360mm Tessar on my 24x18 (mm) Reisekamera the lens. A fresnel or combo screen helps less with wide angle lenses, the wider the less effective.

Beattie screens are brighter, I have one that came new in it's box never used when I bought my Aga Ansco 10x8 Commercial View.

About 7 or 8 years ago I spent quite a time experimenting and testing screen combinations with a Crown Graphic compared to my Wista 45DX which has a Wista factory fittedCombo screen which I find superb. I got to within 1/2 a stop with my own GG and a fresnel fitted to the rear, initially the original Graflex screen was over 3 stops (closer to 4) dimmer. This was actual measurements and visual comparisons.

I'm happy with my scrren/fresnel combinations now with my Crown, Speed & Super Graphics, they all allow easy focussing without a dark cloth which is important as I often use them hand-held.

Ian

N Dhananjay
19-Jun-2015, 06:46
I don't think there is a magic bullet here. In part because there are a number of factors (fine detail, even illumination, contrast etc.) that we experience as focusing screen issues. Some of these issues get further exacerbated by individual differences.

1. Fine detail: Coarse grinds provide a more even surface but fine detail becomes difficult to see. The optimal grind also seems to vary for different people.

2. Evenness: You cannot fight cos^4 falloff. The Kodak 8x10 Masterview cameras came with a hairline that let you focus on the aeriel image and it was instructive to see the effect of going from the center to the corner, especially with a wide angle lens. This is a real issue and not a GG issues - otherwise, we would not need center filters.

3. Subject: Some subjects are difficult to focus. For e.g., if you judge focus by resolution, low contrast scenes will be experienced as difficult to focus - a blank, texture-less wall would be impossible to focus.

4. How do you judge focus?: Do you judge focus by resolution (i.e., fine detail) or by contrast (i.e., the image 'popping into focus') or some combination? Fine grinds will yield more resolution but a dimmer image.

5. What condition are your eyes in?: As we age, our ability to focus close degrades (presbyopia) - that messes up our ability to resolve fine detail and changes the characteristics of the GG that works best for us.

So, I think the best you can do is try to understand how you judge focus and the types of things you like to photograph and then try to get a GG that will be most helpful with those issues and resign yourself to the fact that you will occasionally run into things that your current setup will make difficult for you. It is much more crucial that you ensure the GG/fresnel is in the right spot so that rays of light are focused on the film when the holder is put in. This can become doubly crucial if you use a fresnel, espeically when the fresnel is on the lens side of the GG.

Cheers, DJ

BrianShaw
19-Jun-2015, 06:47
This thread is kinda confusing. Use this, use that, no this here is best. Maxwell is out of my price range so that's one choice I don't have to make. But I'd like to get something reasonably priced that works for my 8x10 Ansco. All of my 8x10 lenses are f9 or worse, I like to work fairly close, and I don't want to fork out even $150-$250 for something that isn't comparatively brilliant.

Yup, that's the way it is... unfortunately. I've used a few GGs over the years and found the Steve Hopf GG to be a good substitute for the SatinSnow, which was a good substitute for any dim or dirty GG. Boht seem brighter and both were shown to be brighter by their manufacturers. For some people even the brightest is too dim and, perhaps, only cataract surgery could correct that problem. If Maxwell is out of the question (I certainly understand!) then suggest you try to Hopf GG. With f/9 lenses you are going to squinting no matter what. :)

Drew Wiley
19-Jun-2015, 09:14
I have Satin Snow both on my Ebony 4x5 and Phillips 8x10 (which came equipped with it). None of the lenses I typically travel with are faster than f/9. I have no problem whatsoever with general composition or critical fine focus. I'll be in deep shade in the redwoods tomorrow. No problem, even with an f/12 max aperture lens. The factory GG on my Sinar is almost as good. A good darkcloth is all you really need. Dark. Screen brighteners might appeal to those who just want a folding viewing hood instead, but I never cared for the manner in which any fresnel interferes with acute focus. Where they can be helpful is when photographing architectural interiors with very wide lenses prone to a lot of illumination falloff. So naturally, addicts of super-wides will have a different opinion from mine.

Pete Roody
19-Jun-2015, 09:34
I doubt there is a single answer that fits everyone's needs. As I get older, my near vision has improved. For this reason I stopped using a lupe for focusing. My natural 'built-in magnification" is fine for focusing. Many of my lenses are slower than F9 and I have no problem focusing with them. I prefer a finely ground glass such as the Satin Snow (not made anymore). I am sure the Hopf is similar. My Arca's have the best system with a Fresnel that I have seen. The Fresnel is in front of the ground glass. Bright, even light and easy to focus with. I never liked the 'hot spots' you get with screens such as the Beattie Intenscreen. I use BTZS hoods and these block stray light and make it easier to focus.

Someone mentioned they use a 10x lupe for focusing. He must be Far Sighted! :-)

Bill_1856
19-Jun-2015, 09:40
Maxwell still seems to be the standard.

Ari
19-Jun-2015, 09:44
Someone mentioned they use a 10x lupe for focusing. He must be Far Sighted! :-)

That's me; actually, I'm near-sighted, and in general, poor-sighted.
I use the stronger loupe mostly for wider lenses, as a normal loupe works less well for me in those situations.
I like it, so as a result, I've sought out finer-grained screens, these work better with stronger loupes.

Drew Wiley
19-Jun-2015, 10:16
High-powered loupes are generally going to be dimmer (unless they are huge), and can be counterproductive by bringing too much of the grind pattern itself into
focus. I prefer around 4X for 8x10 and 7X for 4x5. That's like looking nose-to-print at the pretty darn big print! I do have a tiny little 10X Emo scope which I carry only for emergency backup, esp with roll film backs. With 8x10, the backup can simply be a cheap magnifying glass or even my reading glasses. I did once dropa loupe off a small cliff. I salvaged it. But that taught me a lesson, including how to always tether one to the tripod hook with a long strong. I always tend to drop
filters from time to time, so always carry a spare of my favorite one. Fumbling around with sweatly fingers in storm and wind has both its rewards and penalties.

Pete Roody
19-Jun-2015, 11:12
well maybe i do need a loupe to help with my spelling :-)


That's me; actually, I'm near-sighted, and in general, poor-sighted.
I use the stronger loupe mostly for wider lenses, as a normal loupe works less well for me in those situations.
I like it, so as a result, I've sought out finer-grained screens, these work better with stronger loupes.

BrianShaw
19-Jun-2015, 11:40
well maybe i do need a loupe to help with my spelling :-)

agree... and for me there's more needed:

i need one to help with my capitalization and punctuation

i sure hope somebody makes a 'tri-focus' loupe so we can get everything resolved at the same time

:o

axs810
19-Jun-2015, 11:58
High-powered loupes are generally going to be dimmer (unless they are huge), and can be counterproductive by bringing too much of the grind pattern itself into
focus. I prefer around 4X for 8x10 and 7X for 4x5. That's like looking nose-to-print at the pretty darn big print! I do have a tiny little 10X Emo scope which I carry only for emergency backup, esp with roll film backs. With 8x10, the backup can simply be a cheap magnifying glass or even my reading glasses. I did once dropa loupe off a small cliff. I salvaged it. But that taught me a lesson, including how to always tether one to the tripod hook with a long strong. I always tend to drop
filters from time to time, so always carry a spare of my favorite one. Fumbling around with sweatly fingers in storm and wind has both its rewards and penalties.


*slaps head* I'm a little embarrassed that I didn't know that! I thought a stronger loupe would make it easier to focus or at least brighter....hmm that's good to know!

Wayne
19-Jun-2015, 15:16
You mean Gold Standard, right?


Maxwell still seems to be the standard.

Wayne
19-Jun-2015, 15:20
I rarely use a loupe. They just don't seem to help me focu in most cases, and I have a 4x and an 8x. Maybe if I could actually see the GG I'd find them more helpful. I'm probably in the "focus by contrast" group.

consummate_fritterer
10-Jun-2017, 19:31
From Robert White co. "The unique bright screen effect combines properties of a fresnel with a focusing screen in one piece."

Now that is interesting! How do they combine a fresnel into the ground glass? I ask because I stopped trying to use a fresnel long ago when the ones I got were flexible, and couldn't decide upon what side of the glass it should go (I put it on lens side).

axs810 - the GG in your new-to-you Technika is my favorite. YMMV.

Canham uses a similar design, as does Maxwell. The screen is plastic with a Fresnel on the front and a very finely frosted side facing the back. A piece of clear tempered glass protects the outer surface. I believe there are other companies with similar designs but I can't remember which ones... some of the Linhof offerings perhaps?