PDA

View Full Version : Sinar P2 Bright screen w/ Fresenl replaced with OEM Sinar GG


nbagno
22-May-2020, 15:33
My P2 came with a BrightScreen glass and a fresnel. I wanted to try an OEM Sinar GG because I like the grid pattern better. The BrightScreen glass is clear with a fresnel installed. The OEM Sinar GG is frosted. So, if I want to use the Sinar GG do I keep or remove the fresnel and if removed, won't I need to shim the Sinar GG?

Thanks,
B.S.Kumar
22-May-2020, 15:53
The fresnel on Sinar cameras is installed on top of the focusing screen.

Kumar
nbagno
22-May-2020, 16:02
So the brightscreen gg has the fresnel on the lens side and the gg on the eyeball side, so you’re saying that if I use the Sinar oem GG I should have the GG on the lens side and the fresnel on the eyeball side?


Sent from my iPhone using Tapatalk
B.S.Kumar
22-May-2020, 16:05
Yes. The OEM fresnel can be installed and removed in a second. It has hooks that are latched on to the back.
There is no way to install the OEM items any other way.

Kumar
nbagno
22-May-2020, 16:18
Yes. The OEM fresnel can be installed and removed in a second. It has hooks that are latched on to the back.
There is no way to install the OEM items any other way.

Kumar

The fresnel I have must not be OEM, it has no hooks. I put the fresnel towards me, then OEM GG on the lens side, does not seem right to me. Just seem like I'm looking at frosted glass.
B.S.Kumar
22-May-2020, 16:20
Is your Brightscreen a sandwich of a focusing screen and fresnel? If you're using an OEM GG, you need an OEM fresnel.

Kumar
nbagno
22-May-2020, 19:26
Is your Brightscreen a sandwich of a focusing screen and fresnel? If you're using an OEM GG, you need an OEM fresnel.

Kumar

It’s two separate pieces.


Sent from my iPhone using Tapatalk
B.S.Kumar
22-May-2020, 20:27
The fresnel I have must not be OEM, it has no hooks. I put the fresnel towards me, then OEM GG on the lens side, does not seem right to me. Just seem like I'm looking at frosted glass.

On re-reading this statement, I'm confused. The OEM GG is installed first in its designated location under the clips and the screws tightened. Remember, the ground side is the image forming plane and faces the lens. The fresnel is placed on top, with the grooves towards the lens.

Kumar
nbagno
22-May-2020, 21:21
On re-reading this statement, I'm confused. The OEM GG is installed first in its designated location under the clips and the screws tightened. Remember, the ground side is the image forming plane and faces the lens. The fresnel is placed on top, with the grooves towards the lens.

Kumar

Here are some pictures,first the back.https://uploads.tapatalk-cdn.com/20200523/fc6e43e05f4d1a2bd69c20cc1a99352d.jpg
The way it came to me was with the fresnel on the left installed first the the Brightscreen GGhttps://uploads.tapatalk-cdn.com/20200523/1741cb89ab09a89b804792a1ede670de.jpg
Now with the OEM GG which is on the left and looks slightly frosted. https://uploads.tapatalk-cdn.com/20200523/fa2af66fa45a442567eb45e7cc443879.jpg
So I’m not sure if that Fresnel will work with the OEM GG? If so put the OEM GG in first, the Fresnel on top them, which I tried but it didn’t seem right.


Sent from my iPhone using Tapatalk
nbagno
22-May-2020, 21:50
Ok so after more testing, the OEM GG does not work with the fresnel I have, but the BrightScreen does. I’ll try to use the oem GG without a fresnel and see if the actual images are in focus. I don’t have any shims, it’s just sitting on the back and the clips on top.


Sent from my iPhone using Tapatalk
Bernice Loui
22-May-2020, 22:12
Aftermarket fresnel is not gonna work with the OEM Sinar ground glass. The Sinar fresnel clips in at the long end of the viewing side of the GG.

There should be no shims with the Sinar OEM ground glass to it's seating surface. Direct fit to the precision machined flats with the clips held in place by screws.

Have OEM Sinar frensel for both 4x5 & 5x7 when these cameras were purchased used. They were the first item to be removed before the camera was check and prepped for being used. Over the decades, just never found the fresnel to be much of a focusing aid. It tends to be a focusing and viewing impediment with wide angle lenses.

The far more important GG focusing tool is a loupe.


Bernice
nbagno
22-May-2020, 22:20
Aftermarket fresnel is not gonna work with the OEM Sinar ground glass. The Sinar fresnel clips in at the long end of the viewing side of the GG.

There should be no shims with the Sinar OEM ground glass to it's seating surface. Direct fit to the precision machined flats with the clips held in place by screws.

Have OEM Sinar frensel for both 4x5 & 5x7 when these cameras were purchased used. They were the first item to be removed before the camera was check and prepped for being used. Over the decades, just never found the fresnel to be much of a focusing aid. It tends to be a focusing and viewing impediment with wide angle lenses.

The far more important GG focusing tool is a loupe.


Bernice

Thanks for the confermation on the OEM GG mounting. I'm going to try it like that and see how I like it.

Cheers,

Ned
B.S.Kumar
22-May-2020, 22:28
Judging by your first photo, to me it looks like the item on the left is a GG/fresnel and the item on the right is a cover glass. Does the item on the right have circular grooves? And what is the text on it?

Kumar
nbagno
22-May-2020, 22:30
Judging by your first photo, to me it looks like the item on the left is a GG/fresnel and the item on the right is a cover glass. Does the item on the right have circular grooves? And what is the text on it?

Kumar

You mean the second photo... The glass on the left is the fresnel, to the right of that is the BrighScreen GG. It says BrightScreen on it.
B.S.Kumar
22-May-2020, 22:44
Sorry, yes, the second photo.

Can you focus using only the item on the left, without installing the other item?

Kumar
Bernice Loui
22-May-2020, 23:52
FYI,

Sinar OEM 4x5 ground glass mounting. This one is a meter back for P2, with the plastic GG retainers. Earlier ones have metal retainers. Function and mount is essentially the same.
204018

No shims between the film holder frame machined surfaces to GG.
204019


Bernice
cowanw
23-May-2020, 06:46
Judging by your first photo, to me it looks like the item on the left is a GG/fresnel and the item on the right is a cover glass. Does the item on the right have circular grooves? And what is the text on it?

Kumar

I agree. the Bright Screen labelled glass is possibly just a cover screen laid over the Fresnel/ GG sandwich. The Bright Screen labelled glass is just too clear to be a GG.
nbagno
23-May-2020, 10:16
Is your Brightscreen a sandwich of a focusing screen and fresnel? If you're using an OEM GG, you need an OEM fresnel.

Kumar

You were right on this one. I didn't realize that it was a sandwich... and the brightscreen labeled glass is just a clear cover with the grid lines taped onto it.

Cheers,


Ned