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View Full Version : Best Fresnel Lens/Screens



John B. Kowalski
3-Dec-2000, 23:52
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

Robert A. Zeichner
4-Dec-2000, 00:37
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.

M.
4-Dec-2000, 01:31
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.

Brian Ellis
4-Dec-2000, 10:21
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.

james norman
4-Dec-2000, 12:41
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.

paul owen
4-Dec-2000, 19:30
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

Handcrafts
13-Sep-2022, 15:12
For my Horseman Angle Viewer, I have two new screens made by Bill Maxwell, and they perform well.
The "special" version I got for my wide angles is genuinely exceptional, however the "regular" version is better (more contrasty) with longer lenses.
With my 75mm and 100mm lenses, the illumination is even greater than when I use it for my Rodenstock 55mm.
On my 150mm, it performs much the same as the "regular" version, and it's only from 210mm and higher that I see a noticeable improvement with the "standard" screen.
Given your lens configuration, I'd just buy one of the "special" models and specify the 65mm/135mm combination as the intended use so Bill can fine-tune the screen.
you can read more in this article: Is Fresnel A Type Of Mirror (https://www.handcraftstips.com/2022/07/is-fresnel-a-type-of-mirror.html).

Pieter
13-Sep-2022, 16:15
I bought a new Linhof factory fresnel for my Technika III from Laflex. If I remember correctly, it was a pretty striaghtforward swap, and much brighter. You could co ntact Austin at Laflex and see if he has something for your camera.

Pedro_fiz
14-Sep-2022, 10:35
Hi. I changed my Linhof focus screen by a Rick Oleson one. Rick has a 4x5 model that could be adapted to my camera. I am very happy because is very very bright and the focus is perfect

David Lindquist
14-Sep-2022, 14:31
The original question was asked nearly 22 years ago by someone whose last activity was nearly 22 years ago. :D

Having said that, the three recent replies certainly can be useful to present day readers.

David