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andrea milano
10-Feb-2001, 06:12
Dear Friends and contributors, as some of you know I am very much in favour of this unique focussing screen and keep on wondering why it isn't provided from camera producers as a wothy option to their , sometimes very poor, focussing screen. The only itch that anyone could find id that in extrime temperature conditions i t might the wax and paraffine layer might cristallize or bubble(several degree b elow 0 centigrades and above+ 60-70 degrees centigrades) in most cases all you have to do is protect you camera fron the sun if you are shooting in death valle y(you wouldn't go youself withot as much as a strw hat would you? Why do you lea ve the camera cooking in the sun in your Black car?). However every medal has its side and apart from this debateble point the screen is near perfect. I visit their factory every now and then and it is so nice to m eet people who take you seriously and are prepared to custom make products for y ou, the best thing is that they are prepared to think together with you like in realizing a bosscreem for my Rollei GX 2,8 Edition . I like to promote the use of this screen among large format aficionados and make it known to all those who don't. If you have ever used a screen with a Fresnel lens built in like Wista, you know that they are really badly though and are almost impossible to use with a loupe , try the Bosscreen and wouldn't want anything else. This is my third screen and I'll probably will buy more.

Howard Slavitt
10-Feb-2001, 13:05
Another great option is a fresnel screen made by Bill Maxwell of Maxwell Precision Optics. They are very easy to focus with a loupe and very brigh. A different story altogether than the manufacturer's fresnel that I had used previously. The camera shop owner who helps me customize aspects of my view camera told me he preferred the Maxwell screen to the Boss screens. The Maxwell screens really come into their own with very wide lenses and if you are going to have Bill make one for your widest lens and one for use with your other lens (which I did). Bill also will listen to you and is very patient in trying to satisfy your particular needs.

Dave Anton
10-Feb-2001, 14:04
Howard, does Bill have a website with pricing?

andrea milano
10-Feb-2001, 15:30
Thanks for your answers, I am naturally curious about this Maxwell's Otics focussing screen and would like the contributors who are familiar with it to elaborate on the way this ground glass is mad, infact the comment made about bosscreen being able to be used with a 7x loupe is crucial to explain the qualities of a good screenm any screen which is matted bya a mechanical proces is bound to be made of minute mat dots, bosscreen instead has a layer of uniform (at least for our purposes....) beewax and paraffine enclosed between two glasses (hence the problematic behaviour with extreme temperatures. If Maxwell is the product of a mechanical process or a chemical one this can radically change its performance. Plastics have been used very oftem but to my impression with very poor results. If Arca has a Fresnel towards the lens then its structure will be a part of the image formed on the ground glass , thereefore any loupe would enhance the fresnel lines making the precise focussing almost impossible. In my experience Bosscreen has no need for further fresnell, however maybe with extreme wideangle it might need it, up until 75mm I've never needed any! Getting in touch with Bosscreen can prove tricky. At present they have no Internet site, they are a small company with very few people working there, this is both their stength and their limitation. They will work for you and be flexible but orders might take some time to be fulfilled because of too big a workload. However, you can call them at +31 (0)70 3970061 or write at Stabilix B.V. BurgmeesterHofylaan 84 The Hague The Nehterlands. they sell to privates and they also sell surfave mirrors (for reflex cameras) and they will also polish or coat lenses.

andrea milano
10-Feb-2001, 15:33
My typing notoriously stinks and makes the weardest mistakes seem funny, I apologize.

M.
10-Feb-2001, 17:34
Wouldn't replacing the ground glass screen presently in my camera with a Boss Screen shift the focal plane rearward by the thickness of the front glass of the Boss Screen?

Brian Ellis
10-Feb-2001, 18:50
I suspect the reason camera manufacturers don't supply the Bosscreen as original equipment is at least partly a matter of economics. My 4x5 Bosscreens cost around $150 as I recall. I presently have an 8x10 on order and it cost around $220. With respect to focusing after installing a Bosscreen, I don't know for sure. However, I know that the Bosscreens vary from camera brand to camera brand and I've always assumed this was because they manufacture them so that no focus shift will occur as compared to the camera's original screen. In other words, you don't just order a 4x5 Bosscreen, you order a 4x5 Bosscreen for a Wisner, or a Technika, or a Canham, or whatever. Of course if you've replaced the original screen with something else, I guess they can't take that into account.

andrea milano
10-Feb-2001, 20:07
Brian, It is not exactly correct that camera manifacturers don't supply bosscreen as a standard feature of their camera because Walkers actually do. However the ground glass is positionded so that the wax layer is exactly where the mat glass would normally have been (They use a spacer stip with the same thickness of the layer to insure that, details might be obtained from the directly if you write to the address I gave previously). concerning the second glass it is very thin and smaller than the outside glass, so it is laying inside the camera and wouldn't shift the position of your ground glass. Prices: The price the importers normally charge about bosscreen is almost double of the original price a 4x5 would be around $75 at the souce and a 8"x10" around $120 (must include sending and taxes), in the U.S.A. I am aware of them being imported from Bromwell and I know that Cakume-KJP carrys them too (must check in their american catalogue, I've got it somewhere else).

andrea milano
10-Feb-2001, 20:12
It was Calumet-KJP.......1

Mark Minard
11-Feb-2001, 01:21
For ordering info on the boss screen go to bromwell.com No I am not affiliated with the company in any way - I'm shopping as well as you all are!!!

Paul Schilliger
11-Feb-2001, 05:59
The people there are extremely courteous (contact F. Schroeder). I agree it's an excellent product. After 3-4 years, a very cold day produced some small bubbles into the paraffin, but not ba d and still usable. Would they still sell directly to customers? I remember paying around $ 60 for a 4x5 made on measure for my Technika.

Howard Slavitt
11-Feb-2001, 12:50
Bill Maxwell does not have a website. Call him up and leave him a message. He called me back right away but I've heard it sometimes takes a few days. When you do speak to him, he'll likely talk to you for at least half an hour explaining the physics of the fresnel screens he sells and, based on what focal lengths you plan on using one with, what is the best solution for you. Bill Maxwell (404) 244-0095; Maxwell Precision Optics; P.O. Box 33146; Decatur, GA 30033-0146.

Jan erala
11-Feb-2001, 13:30
Also Dick Phillips who makes the famous Phillips LF cameras recommend the Bosscreen as the best gg-option. He said that the folk in Bosscreen will know exactly what to deliver if you order one for a Phillips. I purchased a Compact II, but didn't take the Bosscreen because I operate often in very cold weather here in Finland. Instead I found the Tachihara screen beeing very fine machined. You can look at the Tachi screen with a loupe without beeing disturbed by the normal fresnel structure. But I sure believe the Bosscreen is outstanding all machined fresnels.

andrea milano
11-Feb-2001, 17:27
Again, Bosscreen sells to private customers so it might be convenient buying direct, I do. American contributors might, but I doubt it find it more convenient to buy through Bromwell. I don't want to infringe anybody's right to make a living but they charge twice as much as the Company which makes the actual GG. The choice is yours..........I rest my case!

Peter Shier
14-Feb-2001, 19:56
Before I ever saw this thread, I ordered Bill Maxwell's screen for both my 'Blad and 4x5. I just installed the 4x5 today and I must say that it makes a huge difference. I had been working on a studio shot with strobes using a Super Symmar XL 110 and had trouble checking focus around the edges despite plentiful modeling light. I just redid the same shot with Maxwell's screen and now there is no problem at all. IMHO this is a great product.

For the record, I am not related to or a personal friend of Bill. I just received a recommendation from someone on the Hassy list for his 6x6 screen and decided to try his 4x5 as well.