Best Fresnel Lens/Screens

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Hi!

Just acquired a minty Linhof Color 45S with reflex mirror hood. It has a plain ground glass. Who makes the best screen/fresnel lens system?? How about installation - if it goes under the ground glass does that change focal plane and cause focus probelms?

New at this - thanx for any help!!!

John

-- John B. Kowalski (John.Kowalski@verizon.net), December 03, 2000

Answers

Yes, if you place the Fresnel between the gg and the lens, you will alter the plane of focus by an amount roughly equal to 1/3 of the thickness of that Fresnel screen. Some cameras are better suited to adding such an accessory than others. One thing I must say is that Linhof goes to a great deal of trouble to align the gg. Their cameras have a sophisticated system of pads that can be micro adjusted to put the focusing screen in the perfect plane. This is not easy to do! If you are unwilling to live with the Fresnel between the gg and your eyes, it's probably best that you ask HP Marketing if they offer a modification for your 45S. Personally, I think too much is made of brighteners. A little practice and patience is all you need to master focusing with an ordinary gg assuming it's not a piece of junk. Your's is certainly not that. I have Kardan Color with just the stock gg and have no trouble with it at all.

-- Robert A. Zeichner (info@razeichner.com), December 03, 2000.

Linhof's "Super Screen" is a great improvement. They often come up brand-new on eBay at quite reasonable prices. I dislike the 1 cm. grid on the Fresnel screen, but apparently many people prefer it. Linhof's printed directions are extremely good, and changing it out is a piece of cake. Whatever you do, pay strict attention to the shims when you remove the old plain ground glass.

-- Bill Mitchell (bmitch@home.com), December 04, 2000.

I've replaced the ground glass on two Linhofs, a Technikardan and a Technika V, with the Bosscreen. I had the replacement done by Steve Grimes just to be sure I didn't end up with focusing problems. It cost about $50 - $75 but for me the peace of mind was worth it.

-- Brian Ellis (bellis60@earthlin.net), December 04, 2000.

i spent years using a plain ground glass with a fresnel behind it before trying a better screen. i first tried the "supersharp" screen but found it comprised two pieces mounted together with some kind of waxy material. the screen had tiny bubbles in it due to imperfections in the wax binder, and came with warnings about using it in very hot situations that could affect the wax. shipped that one right back to calumet and got a beattie intenscreen, which supposedly did not require a fresnel - wrong. the screen is just fine, but it was immediately apparent that i still needed the fresnel, so i popped it in (behind the screen), and have been quite pleased, though it doesnt seem that it is a great improvement over my original ground glass w/fresnel - maybe a little brighter. so, i would suggest that you start by just adding a fresnel and see if that solves your problem all by itself.

-- jnorman (jnorman@teleport.com), December 04, 2000.

Ebony make a wide angle fresnel screen that fits a variety of camera makes - not sure about Linhof though. The screen is reasonable (price) too. regards Paul

-- paul owen (paulowen_2000@yahoo.com), December 04, 2000.


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