Dim Gound Glass Image

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I bought a 16.5" Red Dot Apo Artar for my Deardorff 8X10 View. The image on the ground glass is uncomfortably dimmed even with the aperture opened up to its maximum of F9.5. Would adding a fresnel or a replacement Brightscreen make a distinct difference for easier focussing on outdoor shots? I'm new to this format and would appreciate any practical suggestion.

-- Paul Chan (janpo@tm.net.my), December 06, 1999

Answers

yes fresnel screens make the image brighter, however i would ask, are you using a dark cloth to block out unwanted light for viewing. when it's not raining (i live in seattle) i use and old calmet for outdoor shooting and it has a terrible ground glass, compared to modern GG

For a dark cloth i use a piece of duviteen. you can find this heavy black cloth at grip shops.

if you have more questions or my answer is confusing feel free to e-mail me.

-- Richard Hill (richdee@drizzle.com), December 06, 1999.


I have to assume you are using a focusing cloth. It's doubtful you would see anything outdoors otherwise. If you aren't, get one of those first! As far as Fresnels go, I believe you will have to use a removeable type on the outside of the ground glass. Putting one between the gg and the lens will create film plane alignment problems. I don't believe the Deardorffs were designed for this anyway. Some modern cameras have a set of shims under the gg allowing addition of a Fresnel between the lens and ground glass, but without shims to remove, the camera would have to be re-machined to get proper ground glass/film plane coincidence. My best suggestion is to get a good quality modern ground glass such as the optically coated ones you can buy from Darkroom Innovations. With one of these, an amply sized focusing cloth and a 4-6x loupe, you should have everything you'll need. If it's still too dark, winter is nigh upon us and with it will come nature's brightener. Best of luck!

-- Robert A. Zeichner (razeichner@ameritech.net), December 07, 1999.

Get a Linhoff superscreen. Replaces ground glass. Very bright, can see corner to corner. Only difference from GG is they are a bit harder to focus. Image does not snap into focus like with GG, but it's worth the little extra time to be able to see everything. B&H carries them. Get the no-name brand, they're a bit cheaper, around 75 bucks last time I looked.

-- John Laragh (jwl@taconic.net), December 08, 1999.

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