Focusing Screen

Here are some grabs, can you see any spots?

I am quite happy with the look and the way it renders he DOF, but got to get an other achromat.
The one I have sucks.
 

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Would it be now the right time for us to say: " Frank, you lucky bastard"?

:)

You got a perfect / cinemek style GG for 40€ ??

What else man can say?

p.s. can I borrow it for a while.. :)))
 
Very nice Postmaster !!! For a static DIY adapter. Perfect ! Congratulations!

Off topic : Do you know where i can find Cavision Rods in Germany or Europe?
:-)
 
What do you mean "only" ?

Most (super)35mm film formats are less than that.
What you see in theaters is often made with a gate of 21.95 x 8.47.

Frank
 
looks promising.
would you mind shooting the sky at f16 and maybe some christmas tree lights out of focus.
that would be great.
 
cool, danke.
Vielleicht wenn Du Zeit hast statt der unscharfen Lichterkette
eine andere Punktlichtquelle - Straßenlaternen oder so..
das wär super!

grüße
Matze
 
"only" meaning it will be incredibly difficult for you to focus on an image that small, more vignetting and a really powerful achromat and possible condenser to go with it. that's what "only" meant. otherwise, if all these don't get in the way, I'd like to order a piece and try it out. would you order one for me and I'll pay you?
 
Diffuser? Condenser ?

Diffuser? Condenser ?

Hi postmaster. One thing I'm still confused about.. For a DOF adapter you need
a) Macro Lens
b) Plano-convex lens
c) Focusing screen
d) 35mm lens

Is the fiberscreen a combination of the focusing screen and plano-convex lens ?? Like the Canon EE-a screen ?

In your assembly you only seem to have a macro lens and a 35mm lens besides the fiberscreen..

Postmaster said:
That backfocus issue was driving me nuts.

So I sloughtered one of my old Zeiss Lenses and used the housing - verry elegant micro collimation now hehehe (picture 1)

The components: +10 Achromat in a tube, Zeiss housing with ARRI GG and my trusty Petri 1.7/50 Prime (picture 2)

As you can see I have to hold everything by hand. (picture 3)

This is not represantative since nothinmg is lined up in the propper angles, light drops in and what not but it gives you an idea of no visible grain in an static adapter. ( Picture 4)

With a housing that helds everything together it would give a marvelous picture.

You can see a grid on the ARRI screen - that is dependand of the light angle.
If you got it 100% square to the HVX lens it disapeers.

Frank
Click to expand...
 
You are right, I only have a 10 diopter achromat and the GG, wich works fine till you stop down the 35mm lens - then I get an significant hot spot.

So I probably need an other lens in front of the GG.

Frank
 
Hotspot

Hotspot

Hi Frank,

I read about this ground glass in a German blog (hab die Adresse leider nicht mehr). The guy who tried to use this GG had an enormous hotspot. How much did you had to zoom in to avoid a hotspot and which condenser lense would you recommend (stronger than your 10 diopter lens? Or maybe two 5 diopter on each side of the GG?). I found a German shop with some interessting lenses: http://www.lupenshop.de/ I ordered there once an 20 diopter biaspherical lense which was surprisingly good. So maybe the 13 diopter lense would fit? (http://www.lupenshop.de/content/lup...982742d43f4702060f/Product/Variation/1841&2D2)
Frohe Ostern:-)

Bye David
 
With open lens it´s fine, but as I stop down I get that hotspot petty bad.
A condenser is my next try. Thanks for the Lupenschop link.

Frank
 
Hi,

I was wondering if the condenser has to be plan convex, directly fitting to the GG, or if a bi convex lense would work to. On the page http://www.astroselbstbau.de/achromate.htm you see the "Achromat Zeiss-Hensold Ø 50 mit f 250 mm (which has 4 diopter)" which would maybe work if two of them are being used, one in front and one behind the GG.

Bye David
 
The first black spots where dust, debris and hair. I yust HAD to tryout it and no nerves to clean it before. In the "rose" pictures I cleaned it.

I have some dead fibres in my GG but not in the visible area.

I think there is no way to fix that problem. Don´t know what will happen if you scrape the dead spots with a sharp instrument... probably ruin the whole shabang.

Frank
 
Frank your screen grabs look great! Did I hear you right that this is a static adapter? I've got a Letus Flip and I'd like to convert it into a static adapter if possible. Looks like you've got some great results!

David
 
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