Bosscreen with Fresnel - Has anyone tried it?

[david_karp]

I have been using a Bosscreen that I purchased from Calumet for my

Cambo camera. Calumet also promotes a package of both a Bosscreen and

a Fresnel lens. Has anyone tried the Bosscreen/Fresnel combination?

Does this combination help when using wide angle lenses? Does it help

with dark corners in dim light? I have used a plain ground glass and

the Bosscreen, but never a Fresnel lens.

 

I found a lot of information in the archives about Bosscreens or

Fresnels, but not the combination.

 

Thanks in advance.

[brian_ellis3]

I tried to find the promotion of this combination by Calumet on its web site to see why they recommended it but couldn't find anything about BosScreens at all there. A search for the word "BosScreen" and "Bosscreen" produced nothing. Of course Calumet has one of the worst organized web sites of any major retailer in the world so just because I spent twenty minutes trying to figure out whether a BosScreen was a "dedicated accessory" or a "general accessory" or was a "view camera accessory" or a "field camera accessory" and why within those and all other categories everything was organized by brand name rather than type of product doesn't mean it isn't there, only that it requires more effort than I was willing to expend to find it.

 

I'd certainly bow to Calumet's presumably superior expertise if I could find out why they recommended this combination but I can't. FWIW I've never heard of combining anything - ground glass or Fresnel screen - with a BosScreen. The principal advantage of a BosScreen over a Fresnel is that it is easier to focus because you don't see the lines that you get with a Fresnel screen when you use a loupe. Also, it is easier to use with wide angle lenses because it doesn't introduce the dark perimeter with a wide angle lens that a Fresnel often does. Introducing a Fresnel on top of a BosScreen would seem to eliminate these advatnages. Plus it would give you one of the potential disadvantages of a BosScreen, which is that the wax can melt in very high temperatures and do other bad things in very low temperatures. In other words, it would seem to combine the worst of both worlds. So I don't offhand see why this would be a good combintation but presumably there's something Calumet knows that I'm missing. If so, it's very well hidden somewhere in the morass of their web site.

[brian_ellis3]

Since combining a BosScreen with a Fresnel lens seemed like such a strange combination, I looked in a current Calumet catalog to see what I could find. Unlike the Calumet web site, you can actually find things in the catalog. However, I still see nothing about BosScreens there. They do refer to combining a Fresnel lens with what they call a "Super Sharp Screen" (for $259.95 - ouch!). I don't know what a "Super Sharp Screen" is but it doesn't sound like it's a BosScreen. Are you sure you're using the right terminology when you refer to Calumet promoting a "Bosscreen" and Fresnel combination? It doesn't look like Calumet even sells BosScreens.

[david_karp]

Thanks for the response Brian. Sorry for the confusion. Calumet calls a Bosscreen a "Super Sharp Screen" so that is the name it is under on their website. (Back before I bought it, I did not realize it was a Bosscreen. When I went to the store to investigate, I saw "Bosscreen" on the box, and the name of the manufacturer, Stabilix. The one they carry is the version made to fit Cambo cameras, so I grabbed it.) I referred to it as a Bosscreen in my post because that is what it really is.

 

Calumet sells a combination they call a "4x5 Super Sharp Screen/Fresnel Lens Kit." Here is what they say about it: "This combination of our Super Sharp focusing screen and Fresnel lens produces an extremely bright and incredibly sharp image that can't be beat."

 

My understanding of the advantages of a Bosscreen are similar to those you related in your response. That is why I am curious about the combination and Calumet's claims.

 

By the way, I really like the Bosscreen. My curiosity is raised because I just came back from a trip where the light was often pretty subdued, and I was constantly fighting to see into the corners of the screen with my 90, 75, and even my Fujinon W 125mm f/5.6. (And also because if the combination is worthwhile, Calumet has Cambo Fresnel lenses on sale for $79.99.)

[holger pfriem]

>>The principal advantage of a BosScreen over a Fresnel is that it is

>>easier to focus because you don't see the lines that you get with

>>a Fresnel screen when you use a loupe

 

I use a Peak 15x loupe due to high magnification and the resulting narrow deep of field you barely notice the lines of the fresnel.

 

 

>>Since combining a BosScreen with a Fresnel lens seemed like such a

>>strange combination

 

Why is this a strange combination ? As a user of Sinar P2 fitted with a Bosscreen i can tell you that the fresnel is still very usefull. I think a fresnel lens is allways good to have, but its important that it is removeable e.g. for shoots with great amount of shift.

[brian_ellis3]

David - Thanks for the clarification. I saw the same blurb you did in the catalog.

 

Holger - I didn't say anthing against Fresnels. I said combining a BosScreen with a Fresnel sounded like a strange combination. I gave the reasons why in my original message.