PDA

View Full Version : How to stack a Ebony Ground Glass?



Tim Meisburger
6-Sep-2017, 15:02
169407 169408When I bought my Ebony 45s it came with an after-market ground glass lined for roll film holders and polaroid, but the original glass was included as well. I kept the after market glass on the camera, as I shoot roll film and what Fuji I have left, but now that I have decided to sell the camera, I need to put the original on, and I'm not sure how. When I opened old film box the glass was in, I found one piece of plain glass and three fresnels.

(see photos) I would assume it should be just one fresnel and the glass. So, so I just have extra fresnels, or am I supposed to stack all four together somehow? I'm confused...

Paul Cunningham
6-Sep-2017, 17:46
I know Ebony had at least two different Fresnels. One for most focal lengths and one for wide lenses.

Drew Wiley
7-Sep-2017, 13:10
I would just sell it as is, and include the optional elements well-packed separately, and explain that up front. Let the end user reconfigure it to their own needs. The first thing I did when I purchased a new Ebony was to get rid of the Fresnel and replace the glass itself.

John Layton
7-Sep-2017, 16:19
Was this camera's ground glass frame configured to take the fresnel lenses in front of the ground glass? If so, then be aware that you cannot simply drop in a ground glass without a fresnel lens and expect accurate focus. If, on the other hand, this camera's ground glass frame was configured to accept a fresnel behind the ground glass (closer to the user), then no problem.

Tim Meisburger
7-Sep-2017, 16:52
Okay. I looked at everything again. There are two fresnels, one piece of plain glass, and one piece of plastic with concentric rings. I cannot tell the difference between the two fresnels. I mounted one fresnel with the ground surface to the lens (easy orientation because "Ebony" is marked on the screen), the the concentric ring thing, which seemed to brighten the screen, then the plain glass. This seems to work fine, and the screen is quite bright (much brighter than a pain ground glass).

Sound right?

mpirie
8-Sep-2017, 04:40
Fresnels are effectively concentric rings forming a flat lens used to align the light passing through the ground glass, thus appearing to give a brighter image.

Opinions are split over the effectiveness of using fresnels. My Ebony came with a combined GG/fresnel, which, like Drew, i removed and in my case, replaced with a Maxwell screen.

My suggestion is to put the Ebony screen back in (the buyer will be expecting a standard configuration Ebony) and either include or sell the other fresnels.

Mike

Tim Meisburger
8-Sep-2017, 13:57
Thanks Mike. I remounted the Ebony glass with the fresnel. Its a very nice and bright image.

Tim

mpirie
9-Sep-2017, 04:59
TBH, i didn't notice a big difference moving to the Maxwell screen......to the point where i have the Ebony screen fitted again.

Mike

Steve Hamley
16-Sep-2017, 09:37
The Ebony fresnel/screen is a good general purpose screen and hard to beat. We have to remember that the same amount of light hits the screen (for a given lens and aperture) and the only thing fresnels and fancy screens do is re-distribute that light. That's not to say that you may not like a fresnel screen better than a plain one but there's no magic going on.

Cheers, Steve


TBH, i didn't notice a big difference moving to the Maxwell screen......to the point where i have the Ebony screen fitted again.

Mike