High quality ground glass recommendations

[chametzoo]

Hi All... I'm looking for a high quality ground glass for my 5x7 Rittreck field camera. Any sources you can recommend? I've already gone through two I purchased through USA dealers on eBay. The first one was atrocious! The second one was a little better... but nothing is as good as the ground glass that came in my 4x5 reducing back for the Rittreck. It is labeled "Wista" (Wista made Rittreck cameras for a while). It's beautifully bright corner to corner. It appears to be fresnel and GG integrated made from one piece. I need something just as good for my 5x7 back. The exact size for Rittreck 5x7 is 128mm x 175mm.

[Vaughan]

Rittreck the company became Wista.

I have a couple of Rittreck View 5x7 and have replaced the ground glass a couple of times. There isn’t much difference between the ground glass replacements a have bought. The Wista 4x5 ground glass is moulded acrylic that incorporates a fresnel screen, so it will look brighter than any ground glass without a fresnel. Toyo made a similar fresnel for 5x7, finding one might be a challenge. It won’t be a simple drop-in replacement.

I prefer NOT having fresnel screens, particularly as the formats get bigger. I like clipped corners to check vignetting.

[Rick A]

Several years ago I purchased a 5x7 replacement GG from Keith Canham (KB Canham Cameras) in Arizona. You could also try Fred Newman at The View Camera Store, also in Arizona.

[Greg]

I am of the opinion that the OEM GG that came with Sinar's Norma cameras are second to none. Obviously impossible to find in in newish condition (though I did acquire one GG for my 8x10 in all but new condition several years ago). The GG that comes with Chamonix cameras, I feel is the best currently available. FYI: If you acquire a GG that is ever so slightly larger that what you need - take it to a professional glass cutter to cut.// trust me on that.

[Peter De Smidt]

I recommend making one. There are plenty of 'how-to's' on this site. It's not hard.

[chametzoo]

Thanks Rick.... I've sent emails to each of those recommendations.

[John Layton]

Thing about 4x5 is that the format is small enough that a single piece of acrylic can stay flat without making it unduly thick. Combine this aspect with the skills of someone like Bill Maxwell...and you have one heck of a screen. And yes...that Wista screen is also very wonderful - but not quite so much as the Maxwell.

What works great for my 5x7 is a combination of a Maxwell (acrylic) fresnel (with a "wide-ish" focal length as this works best for overall use) with a Canham (glass) focussing screen. Glass helps to ensure the flatness of the acrylic, and also...as this glass is placed outside of the acrylic, protects the much softer plastic from the elements.

But as I look around these days...it seems that everyone and their uncle carries a single piece, acrylic focussing screen/fresnel combo - in sizes up to huge...at what look like very attractive prices (yes, the Maxwell is a bit pricy). But as I've not experienced any of these other combo-screens personally, I cannot vouch for their quality.

[Peter De Smidt]

I agree with John. I haven't used a better screen than the Maxwell, but I doubt I'd replace mine given the cost.

[Drew Wiley]

I personally prefer just the glass by itself with an appropriate grind. Supplementary screens annoy me, and under certain conditions, even get condensation trapped between them and the glass itself. The right grind pattern is key; if it's too fine, you'll get a hot spot. That being said, I never use very wide angle lenses, which introduce quite a bit of illumination falloff to contend with.

Acrylic is not dimensionally stable; it expands and contracts with humidity cycles, and bows towards heat. The degree of that issue might be minor in the case of something as small as 4x5; but all these seemingly little variables seem to add up.

An exception to what Greg noted about Sinar Norma ground glass - the earlier version of that was not ground at all, but relied on an applied frosting layer, which not only transmits less light, but yellows over time (not recommended). I do like the subsequent Sinar actual ground glass, but prefer Satin Snow gg even better; too bad it's no longer being made.

[John Layton]

For my larger (8x10 and 11x14) DIY screens, I've only used a 500 grit media - and would be very curious about others experiences/recommendations for other grit sizes I might also consider. Thanks!

[chametzoo]

What works great for my 5x7 is a combination of a Maxwell (acrylic) fresnel (with a "wide-ish" focal length as this works best for overall use) with a Canham (glass) focussing screen. Glass helps to ensure the flatness of the acrylic, and also...as this glass is placed outside of the acrylic, protects the much softer plastic from the elements.

Thanks John.... In the "order" of layers you describe, you are putting the fresnel in between the focusing screen and the lens. Wouldn't that require modifying the camera's "seat" for the ground glass so as to attain correct focus (assuming the camera was not designed for the two layers in that order)? I doubt my Rittreck was designed for multiple layers; just a single piece. (The camera's 4x5 back is fitted with an original Wista GG/Fresnel single piece).

Also, can someone direct me to Maxwell's website? I can't seem to find via search.

Thanks!

[John Layton]

Yes...I indeed needed to modify the (5x7 inch) film back to allow the ground glass frame to set forward just a bit - as I remember about a third of the total thickness of the fresnel.

...and its been a few years since I've contacted Bill Maxwell - but if I have a chance I'll dig around a bit to see if I can find this info. In the meantime - maybe someone else can chime in. Bill has been a great person to chat with about fresnel screens as he is intimately connected to their optical physics, and help you get the best possible product for your application.

[JMO]

Bill Maxwell provided me one of his HI-LUX screens designed for my wide-angle 4x5 view camera toward the end of last year, and even put me in touch with another expert who modified my camera so the new screen would focus precisely on the film surface within the holder. So net/net it was a good overall experience again for me (I had purchased a couple of his screens several years ago).

But he told me that his source (in Europe I think) for those screens was no longer willing to make them to his specs and at the quantities he would need, so anyone who might want to purchase one of Bill's screens would need to contact him directly (by phone at +1 *(404) 317-6825, or email at maxwellprecisionoptics@yahoo.com). I think the supply chain issues surrounding the whole COVID saga were the source of that decision by his preferred supplier.

[Doremus Scudder]

As far as I know, Wista is still in business. You can likely get the Fresnel/ground glass screen as a replacement part directly from them or a larger retailer like B&H.

Update: B&H shows the 4x5 Fresnel screen as a special order item - $309.

Best,

Doremus

[chametzoo]

Bill Maxwell provided me one of his HI-LUX screens designed for my wide-angle 4x5 view camera toward the end of last year, and even put me in touch with another expert who modified my camera so the new screen would focus precisely on the film surface within the holder. So net/net it was a good overall experience again for me (I had purchased a couple of his screens several years ago).

Thanks JMO! I just had a conversation with Bill Maxwell and he filled me in on the nature of his product which sounds pretty extraordinary. I'm also considering Keith Canham's product which is a more conventional technology. The viewing system for the Rittreck is important to me for the project I am considering and therefore so is the choice of screens.

Any experience with Mr. Canham's screens?

[JMO]

I have no experience with Canham’s screens.

[John Layton]

Chametzoo...again - my screen for the 5x7 (what you are after, I think) is a combination of Bill Maxwell's fresnel screen plus a Canham ground glass screen. But did you discuss this combination with Bill?

Oh...and nice to know that you were able to contact Bill. I'll do so myself soon to see how he's doing.

[chametzoo]

Chametzoo...again - my screen for the 5x7 (what you are after, I think) is a combination of Bill Maxwell's fresnel screen plus a Canham ground glass screen. But did you discuss this combination with Bill?

Oh...and nice to know that you were able to contact Bill. I'll do so myself soon to see how he's doing.

Thank you John. Bill and I did indirectly discussed that combination. He referred me to Canham if I was not willing to go for the Maxwell screen price tag which is over $1000 now. I'm on the fence about that. On one hand it would give me a screen that I could use in virtually any ambient light situation... on the other it might be overkill and Bill's fresnel along with a decent GG could meet my needs. Bill and I discussed that thoroughly.

I have on hand a modestly priced ground glass that I got from a USA seller that makes them. It has reasonable characteristics and a very smooth grind, but I would definitely want something better to meet the varied ambient light scenarios I am preparing for. To me, a clear view of the scene is very important before exposure. Perhaps investing in Bill's fresnel and using this GG I just described might be a way to proceed.

It seems that Bill's superior light gathering comes from his unique fresnel design... AM I CORRECT IN THAT ASSUMPTION? It seemed that way from the discussion. In either case, Bill recommends I use Bill Moretz to accurately modify my camera's film back.

[Maris Rusis]

The theory of focussing screens has been one of compromise after compromise.

The brightest possible screen is plain un-ground glass but it necessitates aerial image focussing in line with the exit pupil of the lens. I've used such a thing for astro-photography at night.
The next brightest is a coarse ground screen but this exhibits hot-spotting and some focus ambiguity for fine detail.
A "medium" grind screen is a compromise between even illumination and fine detail resolution. I've used such screens in various cameras over the last 50 years.
A very fine grind screen is beautifully even, good for fine focussing, but dim because of its light scattering power.

Fresnel lenses, because of their strong positive power, can turn oblique rays of light which would otherwise miss the observers eye back to that eye thus yielding a brighter image.
A downside of Fresnels is the visibility of lines which may interfere with fine image detail.
For optimum performance the Fresnel is matched to the focal length of the imaging lens. Wide angle lenses need a strong Fresnel, long focus lenses a weaker Fresnel. Change the lens, change the Fresnel ... or compromise.

As per usual I chose the cheap way out of the focussing screen problem by making a really good light-proof focussing cloth.
Ambient light plays out in front of the camera while the back of the camera lives in darkness and the only light I see is the focussing screen.
Given a few seconds of dark adaption I'm reasonably confident of focussing even at f45.

I suspect the technology of focussing screens has room to advance. Do tell, chametzoo, what you finally come up with.

[chametzoo]

The theory of focussing screens has been one of compromise after compromise.

I suspect the technology of focussing screens has room to advance. Do tell, chametzoo, what you finally come up with.

Thank you Maris. I will report back when I make a move. For now, researching and covering all of the bases. I am looking closely at Keith Canham's set of glass and fresnel. That's about $400. I'm also looking at throwing $900 into Bill Maxwell's HI-LUX focusing screen. Admittedly Bill has a certain "figurative tax" on his product because at this point in his career, the number of these screens that he is fabricating for large format shooters is nil. But you can't get it anywhere else. It's a different technology entirely than conventional focusing screens and I'm intrigued by it. Think of it in terms of the contemporary digital sensor technology of pixel sized "micro lenses" in front of the sensor that correct the angle of incidence of light landing on each and every sensor site. That technology has completely solved the aberration problems found in early digital cameras. That's the treatment that is involved in the HI-LUX; it just gathers light in a similar way that you cannot get with grinding and scoring glass and plastic. The demands of my project I am setting up for with 5x7 I think will really require quick and painless viewing and focusing so I'm basing my decision on that. I've spent lots on detailed oriented photographic equipment when I judge that it will smooth the path out for me and my work flow. For instance, a pricey tripod head can really make life easier every single time you have to mount and manipulate the position of your camera.

For me and my photography, there's no more sensual camera experience than seeing your future photograph projected on to glass, clearly and boldly. That view even informs my printing style. In the field it provides the confidence to move forward. For my medium format film cameras it was Beattie screens that did that for me. I'm not a shutter bug; I consider and study each view intently, whether it's a split second decision or an hours long search.

[Vaughan]

I suspect the technology of focussing screens has room to advance.

The only two options are different methods to grind/etch/cut the glass surface, and improving the fresnel screen. A zoom fresnel would be interesting.

[chametzoo]

The only two options are different methods to grind/etch/cut the glass surface, and improving the fresnel screen. A zoom fresnel would be interesting.

Mr. Maxwell would argue that there is more than just those two manual methods. As he describes it, it's more of a nano treatment. That's why it is utilized in the optics world where simple techniques will not meet highly technical demands of science and industry. I'm just telling you what he told me and the many in this forum who benefit from that in their large format photography.

[tom43]

Bill Maxwell and Bill Moretz adapted a „Maxwell“ screen for my Chamonix 45-H1 with the 5x7 back last year. This is really a dream configuration of a light and flexible camera which can be used in challenging light situations. Bill Moretz had to adapt the frame, as Chamonix has quite an uncommon 5x7 screen size. Costs are indeed quite high with around $1.000. To my understanding the supplier (from Germany) is no longer providing the material and there is only few remaining material available for 5x7 screens. If at all…

[chametzoo]

Bill Maxwell and Bill Moretz adapted a „Maxwell“ screen for my Chamonix 45-H1 with the 5x7 back last year. This is really a dream configuration of a light and flexible camera which can be used in challenging light situations. Bill Moretz had to adapt the frame, as Chamonix has quite an uncommon 5x7 screen size. Costs are indeed quite high with around $1.000. To my understanding the supplier (from Germany) is no longer providing the material and there is only few remaining material available for 5x7 screens. If at all…

Hi Tom43.... My screen is on order from Bill Maxwell and my back will be modified by Mr. Moretz. How are you enjoying your HiLux screen?

[phdgent]

I had the famous BOSSCREEN on my Linhof Kardan GT, it is the best, yet delicate, ground glass I ever had. It's made by a Dutch manufacturer but I doubt they are still active, but sometimes you can find them used.

Perhaps it could be an interesting DIY job as a BOSSCREEN isn't grounded, but is made of two very thin sheets of clear glass stuck together with paraffin wax. As the paraffin is thinly matt it acts as grounded glass, not having the typical grain due to grounding.

Be aware that meticulously calibrating when installing this screen is mandatory as the focussing field is in the middle of the focussing glass not on the surface facing the lens, so I had it done by the Linhof service shop (pricey).

The sole disadvantage is that the paraffine melts at 40°C, so working in the open sun (landscapes and architecture) might be a problem, a parasol is an answer on this, but it is worth the effort!

I have one in the Linhof Kardan GT 4"x5" kit that I offer for sale on this forum.

[tom43]

Hi Tom43.... My screen is on order from Bill Maxwell and my back will be modified by Mr. Moretz. How are you enjoying your HiLux screen?

Can´t complain: The screen is as bright as it can get on a large format camera and you can use it quite well also in dimmer environments. The modifications at the frame done by Bill Moretz are excellent. I was first a bit sceptical if the modifications can be detected (different wood color etc.), but it is perfectly done. Unfortunately the screen is not available for 8x10 to my understanding, but only 4x5 and 5x7.

[tom43]

I had the famous BOSSCREEN on my Linhof Kardan GT, it is the best, yet delicate, ground glass I ever had. It's made by a Dutch manufacturer but I doubt they are still active, but sometimes you can find them used.

Perhaps it could be an interesting DIY job as a BOSSCREEN isn't grounded, but is made of two very thin sheets of clear glass stuck together with paraffin wax. As the paraffin is thinly matt it acts as grounded glass, not having the typical grain due to grounding.

Be aware that meticulously calibrating when installing this screen is mandatory as the focussing field is in the middle of the focussing glass not on the surface facing the lens, so I had it done by the Linhof service shop (pricey).

The sole disadvantage is that the paraffine melts at 40°C, so working in the open sun (landscapes and architecture) might be a problem, a parasol is an answer on this, but it is worth the effort!

I have one in the Linhof Kardan GT 4"x5" kit that I offer for sale on this forum.

Interesting. Looking back in some other comments you can find very mixed opinions around the BOSSCREENs. Most people were disappointed as the brightness was behind the promises the company made. It is without a Fresnell and the advantage was more with the surface structure: Without grain, as you correctly wrote. Depends a bit on the needs of the photographer, what to choose here.

[Peter De Smidt]

I had a Boss screen for awhile. Overall, I liked it. I can't remember what happened to it, though. I probably sold the camera I was using it on.

[phdgent]

Indeed a BOSSCREEN coms without a Fresnel lens (with one 'l', it's the name of the French inventor).
Linhof sells a Fresnel you can put over the Ground Glass on the viewing side, which I did when using (very-) wide angles, wider than the S-A 90mm.

The BOSSCREEN I had was at least twice as brighter than the original Linhof Ground Glass...

A pity is doesn't exists for the Silvestri...

(that Fresnel is included too in the Linhof set I am selling)