Ground glass dillema!!!!!!!!!

[ruilourosa]

having using several LF cameras i bought a shen hao TZ45-IIB as it seemed very portable, versatile and reasonably build, although it seems that itīs ground glass is a tad dark. I havenīt received the camera yet...

1š - is it so dark as people say?
2š - should i buy a expensive replacement? (maxwell boss or ebony?)
3š - Should i buy a cheaper alternative, if so which one (hopf or yanke??)
4š - To frenel or not to fresnel (related to the previous question)?
5š - should i try to make my own with abrasives?

Thanks

Rui Lourosa

[ruilourosa]

One more:
is the idea of the frenel loupe viable?

[LJH]

I put a cheap fresnel in my XPO. It's a good option. Mind you, the screen is not that bad without it, but it is much better with it.

Mind you, in a perfect world, I'd have a Maxwell et al screen in it, as well as on all of my cameras!

I use a loupe with it.

[Bill Burk]

Does anyone use the parallax method to focus? This is where you have a clear spot in center of groundglass that you mark an x with grease pencil. Then with a loupe you focus on something and move your head sideways. The image is in focus when the image doesn't move in relationship to the grease pencil x as you move your head.

Just tried this trick on a 35mm RF camera that I suspected of being out of whack, and sure enough it was wacked

[Discoman]

Don't Fresnel the camera unless they actually sell a Fresnel lens for that camera. I don't know about your specific camera, but putting a Fresnel lens on some cameras ends up shifting the plane of focus out of the plane the film resides in. If a Fresnel is offered by the company for your camera, it is probably okay.
I have a screen that isn't exactly the brightest in my graflex, but I've usually just focused it at wide open then stopped down for the exposure. If the ground glass is fairly unevenly illuminated or too dark, I would suggest a boss screen. I heard some people had issues with the beat tie screens, and the bosscreen is usually pretty recommended, even though it dislikes temp extremes.
Just my $.02

[Steve Smith]

but putting a Fresnel lens on some cameras ends up shifting the plane of focus out of the plane the film resides in.

This is only true if the Fresnel goes between the lens and the ground glass. If it goes on the back of the ground glass, i.e. towards the user, it doesn't make any difference.


Steve.

[Ian Grant]

Personally I prefer a fresnel, the best combinations are the one piece fresn/screen (& cover glass0 sold with Wistas, or the Beattie screens in my experience. A Maxwell screen would be similar. I use a fresnel on the rear of my Crown Graphic and that's not too far behind in terms of brightness and usability.

As Steve says if the camera comes with a plain screen then a fresnel has to go behind not lens side of the screen. I've made screens for Shen Hoa's and they are brighter than the originals.

Ian

[LJH]

This is only true if the Fresnel goes between the lens and the ground glass.

Isn't this only if you have to move the GG back to accommodate the Fresnel (i.e. so that the Fresnel is held in place by the GG) as you are changing the relationship between the ground image and the film holder?

I have several cameras with a fresnel in between the lens and the GG and there is absolutely no issue with their focus.

[Ian Grant]

Isn't this only if you have to move the GG back to accommodate the Fresnel (i.e. so that the Fresnel is held in place by the GG) as you are changing the relationship between the ground image and the film holder?

I have several cameras with a fresnel in between the lens and the GG and there is absolutely no issue with their focus.

That's because the backs were designed that way to accomadate the fresnel. Take it out and the screen would be out of register in many cases.

Ian

[Laurent]

I put a cheap fresnel in my XPO. It's a good option. Mind you, the screen is not that bad without it, but it is much better with it.

Mind you, in a perfect world, I'd have a Maxwell et al screen in it, as well as on all of my cameras!

I use a loupe with it.

My Tachihara has a great screen, but a cheap fresnel (got it from a junked video proj from the previous century) still makes using the 90/8 SuperAngulon WAAAAYYY easier. Considering the cost of plastic fresnel, I'd try this option before any other thing.