Bosscreen-more comments and experiences-

[andrea_milano]

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 it might the wax and paraffine layer might cristallize or bubble(several degree below 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 valley(you wouldn't go youself withot as much as a strw hat would you? Why do you leave 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 meet people who take you seriously and are prepared to custom make products for you, 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_slavitt2]

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]

Howard,

does Bill have a website with pricing?

[andrea_milano]

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]

My typing notoriously stinks and makes the weardest mistakes seem

funny, I apologize.

[armin_seeholzer]

Hi Andrea

 

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I also have a Rollei GX since some weeks and I use it allmost for

pictures in the dark. Would it be helpfully for me with the Bosscreen

to have the sharpness on the right place and how much would it cost me

an were can I get one here in Switzerland?

 

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Good light!

[wilhelm]

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_ellis3]

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]

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]

It was Calumet-KJP.......1

[mark_minard]

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!!!

[alpshiker]

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 bad 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_slavitt2]

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_eerala1]

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]

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]

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.

 

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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.

[Doctorpepe]

I know this is an old thread, and the Boss screen may no longer be available, but I am making one with a slightly different set of materials.

 

IMPORTANT: Work under subdued light that has no known UV in it.

 

Materials:

1. Purchase a sheet of clear glass that fits into the frame of the view camera, just as the original ground glass.

2. Purchase a sheet of clear glass that fits into the INSIDE of the frame, just against the first one above.

3. Obtain a bottle of Optical UV curing cement (I get mine from Thor Labs, it is the one used to cement lenses, glass to glass, hard bonding.

4. Buy a Bottle of titanium dioxide pigment (finely ground, obtain from artist painter's supply house like Kremer in NYC).

Procedure:

1. Mix a small quantity of TIO2 with the optical cement in low light.  Mix thoroughly to disperse pigment thoroughly.  The amount you use will depend on how much opacity you want, but it should look about as translucent as paraffin (which is what the Boss screen uses to create the focusing layer).  The actual amount of pigment will probably be determined by the size of your GG and the amount of optical cement you use.  

(Optional:  If you have an ultrasonic cleaner, sit the entire container of optical cement plus TiO2 into the cleaner and let it run for about 5-10 minutes more or less until  any of the air bubbles disperse.)

2. Set the camera viewing frame and insert the top (larger) glass (where the groundglass would have been) and clip it in with the GG clips.

3. Turn the frame over and carefully pour in the mixed optical cement and TiO2 on one side of the glass in the frame.  Might work best to pour a line along the short side of the glass (8" side of an *x10) about an inch from the edge.  Take the smaller clear glass and, starting at the edge where the optical cement has been poured, "tip" the smaller class in from the cement side to the other side.  

4. Allow the smaller glass to "settle" onto the larger glass.  You can gently push about and if any cement leaks over the top, you can just wipe it off with a paper towel.  Excess cured cement will clean up easily later. The optical cement should flow smoothly underneath the smaller glass, much like when you put a glass cover on your cell phone.

5. When you are satisfied that the cement is equally distributed and you have a "hazy" layer between the pieces of glass, then...

6. With the back of the frame (Clip & GG)  facing DOWN, your smaller piece of glass facing UP, expose the sandwich to your UV light source for 10-30 minutes.

7. Once cured, your sandwich is complete, you have a focusing screen that will not melt in the heat.

Cleanup:

1. Take a razor blade and remove any excess cement from the inside of your frame and you can use acetone on the glass to clean up any other residuals.

2. Windex front and back of your new screen and install the frame back onto your camera. 

 

I can send some pix later on.

[dan_fromm2]

Hmm.  Bossscreens are camera specific, are delivered with tape strips on the edges whose thickness places the paraffin layer (used for focusing) at the right distance from the film.

Your idea is cute, but how do you insure that the focusing surface will be in register with the film?