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rdenney
31-Aug-2009, 21:42
I use a Sinar F, usually with 6x9 or 6x12 rollfilm holders. Being that I'm a wide-angle aficionado, being able to use a 47/5.6 Super Angulon (pre-XL) and a 65/5.6 SA was a requirement of the setup. I have installed that lens in a cheapie recessed lens board, and with the bag bellows it focuses easily without having to do anything inconvenient like moving the standards to one side of the tripod mount.

But there is one significant pain the butt with that lens: I couldn't see anything more than the central spot. The ground glass on the Sinar is deeply recessed, and getting to the edges of the frame with a loupe, considering that the loupe had to be pointed at a shallow angle into the lens, was nearly impossible.

Sinar makes a Fresnel and I have a couple of them. I find that with lenses shorter than 90, it causes a range of visual artifacts, such as ghosted images at the edges, the render it useless for the 47 and the 65. It was, of course, probably optimized for something like a 120.

After a lot of research, I finally bit the bullet and bought a standard Hi-Lux screen from Bill Maxwell. This is (yet another) mini-review of that screen and how it works on a Sinar.

The screen comes in two parts. The working part is a plastic focus screen with a ground surface on one side and a micro-Fresnel on the other. The ground surface is, I think, molded--it shows none of the surface damage that comes with grinding or acid etching use for standard glass focus screens. The micro-Fresnel is just that--in a 4X loupe, the Fresnel lines are virtually invisible. They do not interfere with focusing in the slightest. Because the frosted surface is where it usually is, this installs at the same plane as regular ground glass, without any extra fiddling. Some cameras put a Fresnel on the front side, and calibrate for the change in light path. This screen will require calibration to be accurate with those cameras. For cameras where the ground glass sits on hard stops, however, it's a drop-in replacement.

To protect the Fresnel (which faces the user), the second part is a glass cover. The markings are printed onto the cover glass. Mine is a grid with outlines for roll-film formats, which is what I ordered. Other markings are available. You can also make your own markings using a Sharpie pen on the backside of the cover glass. Make a line, let it dry, make another line, let it dry, and repeat until it looks right. Use a fine-point Sharpie and a proper straightedge like a drafter's triangle.

The two parts are sandwiched together and mounted in place of the factory ground glass. The sandwich is a bit thicker. The Sinar clips were fine without modification, but the Sinar Fresnel holder is now a fiddly fit because the new screen consumes some of the space under a clip that the Fresnel needs. In practice, it's not a problem because I doubt I'll ever use the Sinar Fresnel again.

Maxwell makes a screen optimized for very short lenses, but I find that I am now able to view the 47 reasonably using this standard screen.

"Reasonably" means "fighting chance." Before, I couldn't see well enough with that lens to compose the image--now I can compose even in dim light. I can also focus using a loupe right to the edge of the frame. I would say that the 47 is about as good as a 180 was using the standard screen. (And this with a lens that has a two-stop falloff even at f/22.) I can even see the limits of coverage on that lens, which is a very soft edge at f/5.6. In the dimness of my living room, I found that I could actually use that lens without frustration.

A 180 on the Maxwell screen shows no falloff in light intensity on the screen whatever. The scene is evenly illuminated across the screen.

This is a real option for those who want to use ultra-wide lenses that are nearly impossible to see outside the central spot on a standard screen. At just under $300, it's not cheap, but I've sure spent more and gotten less.

Rick "highly recommended" Denney

Brian Ellis
1-Sep-2009, 08:08
I've used many different viewing screens on a wide variety of LF cameras - Maxwell, Beattie, BosScreen, Fresnels that were original equipment on Ebony, Tachihara, and Chamonix cameras, Linhof super screen or whatever they called it, and plain ground glass that came with two Deardorffs and other cameras. The Maxwell is IMHO the best of the bunch, followed fairly closely by BosScreens. The rest weren't worth fooling with. I'm not sure BosScreens are still made, I've seen different information about their present status.

Mike1234
1-Sep-2009, 10:14
Good information, guys. Thank you. I currently have two camera kits... one for sheet film and another small/lightweight kit dedicated to shoot roll film for when I can't carry the former. These both have ultra-wide lenses equal to .28 to .30 times the image diagonal of the film area. But I also have normal and long lenses.

QUESTIONS:
1. Can one use the ultra-wide Maxwell screen for normal/long lenses or is it better to have two backs equipped with corresponding screens?
2. Is the wide (not ultra-wide) screen a better overall choice? This seems to be your finding, Denney, if I followed your post correctly.

rdenney
1-Sep-2009, 12:08
QUESTIONS:
1. Can one use the ultra-wide Maxwell screen for normal/long lenses or is it better to have two backs equipped with corresponding screens?
2. Is the wide (not ultra-wide) screen a better overall choice? This seems to be your finding, Denney, if I followed your post correctly.

I have never handled or looked through Maxwell's screen that is optimized for wide lenses. The Sinar Fresnel does not work for ultra-wide lenses--you get ghosting and double images out at the edges. The focal length of that Fresnel is designed for normal lenses and moderate wides. The Maxwell standard Hi-Lux screen does not exhibit these issues, and it does brighten the image usefully even with the 47.

I suspect that the Maxwell screen optimized for ultra-wides would provide more even illumination, but Maxwell himself does not recommend it for use with longer lenses. He suggested that I start with his standard screen and see how that worked, and if I decided to add the ultra-wide screen, I should do it in a second ground-glass frame. I probably won't do that--the standard screen seems to have solved my problem.

The BosScreen is made from two sheets of glass with a wax material in between. The wax material provides the diffusion and also the focusing surface, and it has to be mounted such that the diffusion layer is in the right place. That requires some fiddling. And there has been concern expressed about the heat stability of the wax for sunbelt-photographers who keep their cameras in their hot cars. I've never handled one so I don't know.

What I personally know is that the Maxwell standard screen provides about the same illumination across the image with a 47mm lens as does a plain ground glass when used with a 180. That is not perfectly even illumination by any means, but it's enough to compose and focus, which is a big improvement over the previous condition.

Rick "call me Rick" Denney

Robert Fisher
1-Sep-2009, 12:56
Rick, to each his own BUT I have owned a number of Maxwell screens and would never consider purchasing another. IMHO they are GROSSLY overpriced and equally over rated.

Steve Hopf IMO offers a superior product at a fraction of Maxwell’s prices.

Hopf provides near instant shipment. Ordering can be done via email without having to endure endless telephone conversations as with Maxwell.

This has been my personal experience - others may and probably will differ.

rdenney
1-Sep-2009, 13:12
Steve Hopf IMO offers a superior product at a fraction of Maxwell’s prices.

Steve Hopf's screens are just plain ground glass, aren't they? If so, that seems to me a different product for a different purpose. I had no complaints with the Sinar plain ground glass, which is acid-etched and very high quality. It was just the wrong solution for the wide-angle-lens problem I had, though it was fine for lenses of 120mm and longer.

Have you used such a screen on a 4x5 camera with a 47mm Super Angulon?

Rick "who would gladly buy them for any situation requiring a plain ground glass" Denney

Brian Ellis
1-Sep-2009, 14:02
Rick, to each his own BUT I have owned a number of Maxwell screens and would never consider purchasing another. IMHO they are GROSSLY overpriced and equally over rated.

Steve Hopf IMO offers a superior product at a fraction of Maxwell’s prices.

Hopf provides near instant shipment. Ordering can be done via email without having to endure endless telephone conversations as with Maxwell.

This has been my personal experience - others may and probably will differ.

Hopf makes a plain ground glass. It may be an excellent ground glass but it's still just a ground glass, which is an entirely different product from a Maxwell screen. I'm surprised that despite thinking the Maxwell screens are overpriced and overrated you nevertheless have owned "a number" of them. Seems like it would have been wise to stop at one if they're overpriced and overrated.

Robert Fisher
1-Sep-2009, 14:24
Brian, please correct me if I am mistaken, but did I ask anywhere in my post for your personal opinion of my actions? I clearly stated that I was expressing my opinion from having used Maxwell screens. I reserve the right as anyone else to buy and sell any product without you public personal observations or receiving your approval.

Rick, yes I have used two different Maxwell screens on a 47 - personally I did not like it and it was counter productive on normal lenses. But I am glad that you are pleased with your purchase.

rdenney
1-Sep-2009, 14:34
Rick, yes I have used two different Maxwell screens on a 47 - personally I did not like it and it was counter productive on normal lenses.

Actually, I was asking if you had used a the Hopf plain ground glass screen with a 47. I assume that you have, based on the above. If so, how the heck could you see the edges well enough to know what was in the picture, let alone well enough to adjust the camera movements and check focus? I sure couldn't do that with the Sinar screen.

Rick "who evaluates products in terms of requirements fulfilled" Denney

Mike1234
1-Sep-2009, 15:04
OFF TOPIC: Has anyone tried making a ground glass by centering new glass on a rotating sander (ultra-fine grit) and letting the spinning action/grinding do the work? I know the patern will be random compared to a fresnel but I'm curious as to how the circular grinding pattern would work directly on the glass. It's just something oddball to try.

Jeffrey Sipress
2-Sep-2009, 09:51
Glad to hear that you survived the aural onslaught that comes with dealing with Mr. Maxwell. Yes, his glass is fine,but it took a few weeks for my ear to heal.

George Hart
2-Sep-2009, 10:28
Yes, his glass is fine

Glass?!! Plastic, and I agree with others that it's definitely overpriced. Very good, but in my opinion, his charges are too high.

rdenney
2-Sep-2009, 11:41
Glass?!! Plastic, and I agree with others that it's definitely overpriced. Very good, but in my opinion, his charges are too high.

Well, you know, that depends on one's perspective.

There is a difference between price and cost. I don't know, nor do I care, what it costs Maxwell to make these screens. For any product, there is a relationship between market price and production quantity. One price might result in 1000 sales, and another price might result in 10,000 sales. It is possible that the former could actually result in greater total profit. And if the production capacity is 1000 anyway (at least at a particular quality model), he be offending his investors to sell for less.

The fact is that I was willing to spend that for a screen, because the existing screen (which is of unassailable quality but a different design) wasn't good enough. There are no alternatives available that I have been able to find. The Beattie screen (no longer made) is not as good to my eyes. The BosScreen (no longer made) is reported to be pretty good, but may have other issues. Those were not always that much cheaper, but whatever their price, their business model ultimately failed. Maxwell is still in business after a long time, so his pricing must not be that out of line. Was the price worth it to me? I refer you to Post #1. I have spent a lot more and gotten a lot less value many times during my photographic experience.

Rick "who does not believe a seller owes the customer a low price" Denney

JosephBurke
2-Sep-2009, 12:31
My Two cents on Bill Maxwell's Screens.... I have a standard Hi-Lux screen on both of my 4x5's....one on my Deardorff and one on my Linhof MT......I also have a Bossceen for my Deardoff.....it ( the 4x5 Bosscreen) is back in it's box.......Note that my widest 4x5 lens is my CZ 75 mm 4,5 Biogon....I can easily make do with the Maxwell screen though not optimum for a rather wide lens but wide open the Biogon is a breeze to focus......the Bosscreen is worthless on a wide lens.....I use a Linhof 4 way reflex viewer and can easily get critical focus achieved without a loupe on the Linhof....the Hi-Lux screen is that sharp......the Bossceen is sharp too but not bright enough and is much much harder with a wider lens......so to me you are getting a very finely rendered image and brightness with Bill's Hi-Lux screen.....the Bosscreen lacks the brightness of the two....I'll take the Hi-Lux.......OTOH...I have a Bosscreen on my 8x10 DD and love it....Bill has an 8x10 screen (He'll tell you it will not be as good as the 4x5 Hi-Lux) but the 4x5 Hi-Lux is as good as it gets in my book.....well...as good as it has gotten for me...........For 8x10 Plain GG I think my original GG on my Kodak Master is the best standard GG I have ever seen.....If Steve Knopf's GG is as good as the KMV GG then he has a terrific product.....

Mike1234
2-Sep-2009, 16:17
What's with the bickering and accusations on otherwise perfectly good forums? We sound like a bunch of old bitty's with nothing better do do than b!tch and accuse each other of foul play.

Joanna Carter
3-Sep-2009, 00:55
For any product, there is a relationship between market price and production quantity.
This is a problem that I can see for my anticipated film envelopes. Nowadays, so many people expect the kind of prices that mass production in China has given us; but when it comes to a small manufacturer and low volumes or custom made parts, these things simply cannot be made for the kind of prices to which we have become accustomed.

ljsegil
3-Sep-2009, 03:22
Joanna,
Though this is OT, I hope you do understand (and I'm sure that you do) that there is a cadre of us on this forum that will welcome whatever envelope system you are able to develop at whatever price you need to charge to fairly recoup your efforts and support your enterprise over time. Analogously, there are many of us who are willing to pay Bill Maxwell for the obvious quality that his product delivers (if we can just get past the phone call). May your work bear fruition, and we will bear the cost (especially if you can see a way for larger formats! (yet another gratuitous dig)) as its expected quality and utility will deserve.
Best,
Larry

Joanna Carter
3-Sep-2009, 03:34
...if we can just get past the phone call
Ah yes, the phone call.......... and I had to order two screens at separate times :eek: ;)

I have been rather busy preparing for an exhibition but I am hoping to get back on the envelopes soon.

Daniel Unkefer
3-Sep-2009, 04:20
After half an hour, I tell him I'm at work, on my lunchbreak, and I have to cut the conversation short, to get back to work. Worked for me. ;) ;) ;)

I bought a pile of "seconds" from him, to use in the medium format system I was using at the time. Still have the screens, I won't be selling those.

Mike1234
3-Sep-2009, 09:15
This is a problem that I can see for my anticipated film envelopes. Nowadays, so many people expect the kind of prices that mass production in China has given us; but when it comes to a small manufacturer and low volumes or custom made parts, these things simply cannot be made for the kind of prices to which we have become accustomed.

Sad but true.

Peter De Smidt
3-Sep-2009, 10:16
I've been very happy with my Maxwell screen. I prefer it to a Bosscreen, Beattie intenscreen plus, or Linhof super screen, at least with my lenses. If you think Bill is a little talky on the phone you should try Peter Gowland :)

pocketfulladoubles
4-Sep-2009, 16:43
I rather enjoyed my conversation with Bill. How often do you get that kind of customer service where the guy who actually makes the product is willing to sit down and explain the finer details of his field and product. I consider it a value added service. At any rate, I purchased his Ultra-Brilliant screen and it's second to none. I don't use a 47, but I can focus my 65 inside in questionable light just fine. I can focus my 90 at night just fine. It is well worth the money.

Nathan Potter
4-Sep-2009, 17:36
Rick, thanks for your splendid description of the Maxwell screen. I've been wondering how this is made and he seems to have it right with the integral Fresnel and ground surface. The glass backing plate needs to be there to protect the plastic Fresnel. I take it that the pitch of the Fresnel is quite high per your description of it being nearly invisible with a loupe. I'd be interested in what the pitch is and what the thickness of the assembly is also.

I also assume that the angle of the molded Fresnel prisms (the Fresnel focal lengths) are different for the wide, normal and tele lenses.

Nate, in a focusing screen fixing mood, Potter Austin TX.

Bill_1856
5-Sep-2009, 06:24
About the price: Think of it as a lens for the rear of your camera -- you'd certainly be paying more for a conventional lens for the front.
(Incidentally, the reason that he charges so much is because half of the cost is lost due to acromonious divorce proceedings, and he never sees any of it. After what he went through, we're lucky that he's still in business at all.)

Bob McCarthy
5-Sep-2009, 06:35
(Incidentally, the reason that he charges so much is because half of the cost is lost due to acromonious divorce proceedings, and he never sees any of it. After what he went through, we're lucky that he's still in business at all.)

Thats certainly doesn't make me want to pay a higher price. So half (?) of what i pay goes to the Ex.

What state is that. I agree all states require sharing assets. But a division of the revenue going forward??

Besides price is based upon features and the competitive field, not one's debt service.

Gezzz, I need a new fresnel for the newly acquired Sinar too.

bob

Bob McCarthy
5-Sep-2009, 06:59
So what does he charge?

It not on the site where his products reside.

I was reasonably happy with the Linhof Super-screen on the Tech 2k I owned.

That's not much more than $100 as I recall.

It there a significant difference for the money, what ever that is?

bob

David Rees
5-Sep-2009, 07:14
Bob,

In July I contacted Bill Maxwell concerning a screen for my Ebony 45SU. He sent me a very informative email by return. His HI-LUX Brilliant Matte 4.7 screen was $295, and the Ultra Brilliant was $395.

Being based in the UK, shipping + customs duty + VAT would convert these costs from $295 to Ł295, etc., so at that time I didn't place an order. I decided to continue to use my Walker 45 XL with my 47XL and 58XL (the Walker has been fitted with a BosScreen, which works very well with those lenses for landscape use).

I did originally try to get a BosScreen for my Ebony, but as others have said, they are no longer in production.

Len Middleton
5-Sep-2009, 07:31
Bill,

That is unfortunate that he has those obligations, but as mentioned the market determines the price. What are the available options and expected benefit, and what is it worth to the individual purchaser?

Besides, if we take that perspective, then I should get special consideration as I have an addiction that causes me to purchase stuff that I do not absolutely need and spend over $4 a sheet each time I use it, and...

Oh right, so does everyone else on this site...

Never mind,

Len

P.S. Was his divorce a result of him spending all his time on the phone and not talking to her? :D

David Karp
5-Sep-2009, 08:36
I guess it is good sport to make fun of Mr. Maxwell and his desire to converse with customers and potential customers.

When I was thinking about buying one of his screens, I had a long, very enjoyable, very informative conversation with him. I learned a lot about his product. Ultimately, I decided not to buy his product. I also had another screen that was allegedly one of his that I purchased through Ebay. He spent a significant amount of time explaining how to sand down the edges so that it would fit in my camera. He was very concerned that I would damage the screen, and so explained what to do in great detail. Based on his description, I later determined that the item was not a Maxwell, but something else. It sure was nice of him to spend the time on something like this, where he did not stand to make on penny, even though I was an interested potential buyer of another screen. Certainly, if I decided to purchase, I would not hesitate to contact him again.

I suppose that we would prefer sellers who sell poor products, don't communicate, don't back up their products, and treat us poorly.

Len Middleton
5-Sep-2009, 08:56
David,

In all fairness, I have not talked to Mr. Maxwell and taken advantage of his sage and generous council on the subject of his screens.

My off hand comment was related to a number of comments made by others and related to my own situation. My wife and children warn first time visitors not to talk to me about cameras and photography, as apparently I can go on for some time on the subject...

I am otherwise considered somewhat closed mouth...

It was just intended as a humourous observation on what may be a virtue to some, may be viewed differently to others.

And yes, (presumeably like you) I prefer to deal with sellers who sell good products (from my perspective), who will provide the needed information, and stand behind their product. I think there are a number of individuals who have a reputation for those virtues and their praises are sung loudly on this site.

Hope that helps to clarifies things,

Len

Bill_1856
5-Sep-2009, 08:58
The point I thought that I was making was that the very high price of Maxwell screens is not because he is greedy, but due to unfortunate factors beyond his control. It's almost like the guvrnmet put a 100% tax on the things.
Mr. Maxwell is, in fact, one of the Really Nice Guys in the photo industry and as we've seen, there ain't enough of them left (such as the Satin Screen guy who was apparently hounded out of business when trying to deal honestly with some of our LF breathern)!

David Karp
5-Sep-2009, 09:09
Len,

My comment was not directed at you. There are comments farther up the thread, and these comments seem to be made every time Maxwell's name comes up. I guess I was thinking that if I was Maxwell I would not appreciate the regular ridicule from part of his client base.

And you are right, it is not just Maxwell. I spoke to Keith Canham once. The call went on forever, and it was at least as much my doing as his.

My comment is just trying to look at our dealings with him from a different perspective than we usually get.

Len Middleton
5-Sep-2009, 09:22
And you are right, it is not just Maxwell. I spoke to Keith Canham once. The call went on forever, and it was at least as much my doing as his.

My comment is just trying to look at our dealings with him from a different perspective than we usually get.

Exactly!!

If it is a phone conversation, then both parties impact its duration...

And if you are calling for advise, then it is just common courtesy (and common sense) to listen to the advise you asked for, even if it may be in more detail than you intended or wanted. There may be more to the subject than you thought...

oris642
5-Sep-2009, 11:41
I'm about to order a Maxwell screen for my Chamonix. It just occurred to me why I need one for my 90/f8 - I think it's because of my laser eye surgery a couple of years ago. While I have 20/10 vision during the day, my night vision has decreased considerably since the surgery (and they warned my that it was one of the side effects). My point is, I'm wondering if that is why some people see a lot of difference with their Maxwell screen, while others don't seem to notice much difference?

rdenney
6-Sep-2009, 20:40
Okay, folks, here's the field report:

While standing in shade, I am able to clearly focus and compose with 180mm (f/5.6) and 240mm (f/6.8) lenses without using a dark cloth at all. While standing in the sun, I can still see to rough focus and compose, and used the focus cloth only for fine adjustments of tilt.

With a 65/5.6 Super Angulon, I was able to see and compose roughly, even in sun, without the focus cloth. I could put the loupe on the screen and focus to the edges. The screen is not optimized for this focal length, and there is still a bright central spot. But I could still see quite a lot even without a dark cloth.

With the 47/5.6 Super Angulon (which does not have coverage for 4x5), I needed the dark cloth to see the limits of coverage and to compose the image. But I was able to clearly compose the image using the dark cloth.

With all the lenses, I was able to focus right to the edges using a straight-on 4x loupe at taking aperture (which ranged from f/16 to f/32).

I was working with the 6x12 format, so I did need to see to the edges of the frame.

To answer some questions, the standard Hi-Lux screen is optimized for a normal lens--about 150mm. If that caused any problem at 240 I could not see it. And though the 47 and 65mm lenses still showed a very bright central spot, the screen made possible what had not been possible with the Sinar standard screen.

Other answers: I don't know the frequency of the Fresnel. But I don't think it's so much the frequency as the precision of the Fresnel shape. The points are so sharp that they disappear. The ground side is so fine that you see no grain, even stopped down. The images is completely smooth and bright, and you really have to look (with a loupe) to see the Fresnel lines at all. There is absolutely no problem with critical focusing using a loupe with this screen.

If being able to do those things is worth $300 to you, then you know what to do.

Rick "calling it like he (finally) sees it" Denney

Joanna Carter
6-Sep-2009, 23:22
Excellent report Rick. You have managed to put into words just how good these screens are. It is the amazing combination of features that gives you the sharpness and brightness of image, over such a wide range of focal lengths, without the obvious fresnel lines that something like the Ebony fresnel gives you.

Uri A
7-Sep-2009, 00:07
Has anyone out there got one of these on a 8x10 Deardorff (or whatever 8x10 - I'm not sure the camera matters does it)? I'd love to know what you thought of it as far as using wide lenses (150mm) goes.

rdenney
12-Nov-2009, 23:52
I'm sitting here in my home office needing to do books for an organization that I'm treasurer of, and looking for an excuse to procrastinate a little longer. I look over and see the Sinar sitting on a tripod, and in the other direction I see that my old Tamron 90mm macro lens is mounted on my 5D, and so to hell with the books.

(This is what it's like to be an engineer, by the way.)

So, I mounted a lens on the Sinar and set up Tripod #2 to hold the Canon, and took some pictures of the Maxwell screen.

I have attached two photos. The first is a general view of the back of the Sinar, pointed at my messy desk. The room is very dark--this exposure was 1/25 at f/2.5 (wide open on the Tamron) at ISO 1600. As you can see, the image on the ground glass is quite viewable without a dark cloth, even when the ambient light properly exposes the camera back. The lens on the view camera is a 210/5.6 APO-Sironar-N, wide open. It is focused on the lamp, which is the blown-out spot towards the right of this image. I have bag bellows on the camera, sticking out around the camera.

The second photo is a different exposure, made at 1:1 with the macro lens focused on the Maxwell screen. I cropped away everything but the lamp, which in the raw digital image was 1100 pixels tall (or 9.1mm on the image plane--you can see that the lamp image just fits in the 1-cm square on the focus screen cover glass). If my arithmetic has any meaning, this enlargement is something like looking at the ground glass through a 20x-ish loupe. My intent with this image was not to show how sharp the Maxwell screen is, though it does that, but to show how clear it is and how subtle the Fresnel lines are. This photo exaggerates them considerably--you can just see them with a more normal 4x loupe. In no way to the Fresnel lines on the screen prevent sharp focus using a loupe.

One interesting thing was that the Fresnel lines required a slightly different focus of my macro lens than did the focused image itself. The focus in the image is on the Fresnel lines, which rendered the focused image slightly unsharp, even though I stopped this photo down to f/16. The exposure was 1/6 at f/16 at ISO1600, and it was given about three stops less exposure than the first image to keep the lamp from blowing out completely.

Then, for a final measure, I took my Pentax spot meter and measured the EV of the computer monitor visible on the ground glass. From the camera position, it measured EV 9 in real life, and EV 5 on the Maxwell screen, projected by an f/5.6 lens.

You can see from the first image the edges of the focus screen and the different edges of the cover glass. They are sandwiched but not cemented, so it is possible to make any marks you want on the back side of the cover glass. I bought the screen with the 1-cm grid and format marks for roll-film formats, which I use quite a lot.

Not too shabby, eh? People keep challenging the value of this screen because of its admittedly high price, but I've sure paid more and gotten less with many of my still-successful photographic purchases.

Rick "who'll do this again sometime with a 65mm lens and add to the thread" Denney

rugenius
13-Nov-2009, 10:17
It's interesting that here, in this thread, people took a pretty open look at improving performance on the Sinar screen by installing a 3rd party screen intensifier (Maxwell). If I understood the first post, the original GG/Fresnel from Sinar combined with short focal length wide angle lenses was useless. And I think many people understand limitations of certain screens, and why the physical optics causes a problem of this nature.
Conversely, a similar thread on the screen for the Chamonix 045N was all about how screwed up the manufacturer was,... because people couldn't focus worth a darned in those same conditions as described by rdenny. Chamonix has actually posted a strange apology on the website for this issue. I see it as an obvious shortcoming of placing a thick Fresnel between the lens and GG. I'm not going to complain about it. If the factory setup isn't satisfactory,... there are solutions...

Anyway, it's really good information, and clearly a tangible benefit of switching to another screen like Maxwell.

Many thanks for the feedback.:)

Steve Hamley
13-Nov-2009, 13:35
Has anyone out there got one of these on a 8x10 Deardorff (or whatever 8x10 - I'm not sure the camera matters does it)? I'd love to know what you thought of it as far as using wide lenses (150mm) goes.

Uri,

I have a Maxwell screen on a 8x10, installed by the previous owner.

It works O.K. with short lenses, which probably doesn't help you a lot. Bill can optimize the fresnel to the focal length range of you're interested in, so I assume one optimized for short lenses would work even better.

How well it works (ie, is it worth the money?) depends on more things than you might at first realize, including the lens' maximum aperture, what your old screen was like, and not the least, what you want and expect out of the screen.

Mine's very nice with a 150mm f/5.6 Schneider SS XL, but I doubt I'd pay the premium for it. The screen is considerably more useful with smaller aperture lenses like the 165mm f/8 WA Dagor. So there's a greater argument for such a screen if you're using small aperture lenses. However, the camera I usually use the 165mm on actually has a Steve Hopf ground glass in it (Keith Canham also makes a very good glass), and it works fine too although like all plain GG versus fresnels, it gets quite dark in the corners with wider lenses.

A fresnel is also an upgrade to many vintage and other older ground glasses. Quite a few people I know have upgraded Sinar screens to various alternatives, and a lot of us have upgraded vintage screens in 2Ds and so on. The older screens were generally coarser than more modern screens, and there's a reason for it although some of it at least is current preference. Finer screens are brighter, but harder to focus and have more of a "hot spot" (fall off). Coarser screens are dimmer, some times a lot, but "pop" into focus more easily and have less of a hot spot. My advice is if you have a screen you find too dim for your tastes or lenses and have decided to upgrade to a fresnel, get a Maxwell. I wouldn't go half way.

Finally, I've discovered via this forum, that there are other uses for bright screens! Apparently to some folks, a bright GG image is as much a part of the LF experience as the negative/transparency is, even to the point of being bright to the point of being more difficult to focus, and fresnel lines seem to bother them. Personally I could care less as long as I can focus critically, but to each his own. The Maxwell seems to have less pronounced fresnel lines.

So there you go, I don't know if this answered your question, but I hope it helps.

Cheers, Steve

Robert Fisher
13-Nov-2009, 15:16
Steve, i just purchased an Ebony 810 fresnel to go on my SW810 on top of a Hopf boro ultra bright screen - wow it is like ultra, ultra bright at f22 for critical fine focus. Currently I only use a 240 Sinaron SE on my 810. Today I took a few shots without using a loupe - a piece of cake.

My quest has always been for a mega bright screen - not only for the LCD quality but mostly to compensate for having vision in one eye only (my world is darker than most).

I ordered and paid for my Ebony fresnel last Friday (11/6) and received it this morning (11/13) from Japan - no drama just results.

rdenney
13-Nov-2009, 15:20
Finally, I've discovered via this forum, that there are other uses for bright screens! Apparently to some folks, a bright GG image is as much a part of the LF experience as the negative/transparency is, even to the point of being bright to the point of being more difficult to focus, and fresnel lines seem to bother them. Personally I could care less as long as I can focus critically, but to each his own. The Maxwell seems to have less pronounced fresnel lines.

Focusing critically, including in the corners, is indeed issue number 1. But so is being able to compose the image, which for me requires being able to see all of it at once.

That's where Maxwell's screen shines. It provides the brightness without in any way limiting the ability to focus critically.

Rick "and all that in return for mere dollars" Denney

Steve Hamley
13-Nov-2009, 15:32
Robert,

If you don't mind me being nosy, how much was the Ebony fresnel? PM if you don't want to post.

Cheers, Steve

matteoprez
4-Feb-2010, 11:59
Hi everyone,

I just wanted to share my experience on Maxwell screens. I know this is a large photography forum, and although I do not have one (yet), I am an analog photographer nevertheless and am planning to get a large format camera soon (Calumet, I think).

I recently bought a Rolleiflex 3.5F Planar and the viewfinder was rather dim. So, after investigating a bit I decided to go for the Bill Maxwell screens. I ended up buying two, one for the above-mentioned camera, and the other for a Rolleiflex 3.5 Automat MX model.

Both models are 'Hi-Lux Brilliant Matte', and I could not be happier. Such amazing screens, they're bright as hell. Moreover, before buying them I have contacted Bill, who explained me at length the benefits of each individual model.

I cannot express enough my gratitude for such incredible glasses. Top notch!

Matteo
www.flickr.com/matteoprezioso

Robert Hughes
4-Feb-2010, 12:31
Focusing critically, including in the corners, is indeed issue number 1.
Especially when using those Galli- style meniscus and petzval lenses! :p

ambroz
24-Mar-2010, 00:18
Is there any producer in Europe who makes similar screens like Maxwell?

If not, does anybody has his e-mail address (if he has one)?
maxwellprecisionoptics@toast.net is not valid.
I don't want to have a long phone conversation from Europe.

Ambroz

lloyd
24-Mar-2010, 09:40
I just put an ultra fine GG from photofixation (ebay) together with a fresnel from apalert (ebay) on my 5x7. $80. total. The fresnel is kind of thick but very fine lines, 200mm focal length. GG is very nice, v. fine. A HUGE low priced improvement to my regular GG.

The fresnel is thick enough to overfill the slot in my Deardorff but it works out ok anyway. 40. for a new fresnel is an excellent price imho.

lloyd

CarstenW
27-Mar-2010, 06:19
Is there any producer in Europe who makes similar screens like Maxwell?

If not, does anybody has his e-mail address (if he has one)?
maxwellprecisionoptics@toast.net is not valid.
I don't want to have a long phone conversation from Europe.

Ambroz

To my knowledge he doesn't deal through the internet. You could use Skype to make the call, however, and keep the cost very low.