Confused, Subject blurred, background sharp!

[10speeduk]

Hi all, I have had two shoots with a Speed Graphic and Ektar Aero. Both times all shots show the background pin sharp and the subject blurred, like the complete inverse of the shot I thought I took.

The 1st shoot was portrait so I thought maybe it was user error. Today I shot my car on a tripod and used a loupe to focus on the glass. I made sure the tripod movements were looked off tight and made sure that the focus rail was locked. Everything looked perfect before I slid the film in.

So I am baffled.

Is it possible that this can happen? or am I cocking it up? I wonder as the focus is completely the opposite, not a little bit off but completely the opposite of my intention!

Cheers

Paul

 

[jcc]

Severe backfocusing issue from misaligned ground glass vs. film holder? That, or your loupe might have a correction that you don't know about.

 

[10speeduk]

Severe backfocusing issue from misaligned ground glass vs. film holder? That, or your loupe might have a correction that you don't know about.

Thanks jcc, I will post a shot once they are dry. Thought I was going mad!

 

[10speeduk]

I used this loupe:

KAISER 2334 8X LOUPE STAND LUPE MAGNIFIER SLIDES FILM VIEWING K2334
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[bdial]

The GG may be installed backwards. Is this camera new to you?
Is it plain ground glass or is there a fresnel?

 

[Dr Croubie]

If your background is sharp and foreground not, then your film is closer to the lens than the ground glass when you slide the filmholder in. Is there any play in the GG? Are there any shims between the GG and its holder? Do you have a Fresnel or other screen installed?
If you're using an f/2.5 Aero Ektar wide open, every micrometer out is going to have a huge effect on the photo, only f/16 or deeper can cover focussing mistakes (depending on FL and distance, of course)

 

[AgX]

Severe backfocusing issue from misaligned ground glass vs. film holder? That, or your loupe might have a correction that you don't know about.

If the loupe is only used on the ground part of the screen any mis-setting would not give that effect, it only would affect the maximum sharpness of the screen image viewed by it, not the fore-/background relation.

 

[gone]

Right, probably a fresnel/G.G. issue. Make sure they're properly oriented.

 

[10speeduk]

Cheers guys, on the fresnel (ribbed glass?), which way should the ribs be pointing?

here I was focusing on the nearest headlight!

 

[10speeduk]

Ok, well, I replaced the fresnel and glass recently. I just followed the orientation of the fresnel that was in there. It has the ribbed glass facing the lens. I guess this was wrong, and explains how both shoots (with diff fresnels) had the same issue! Thanks all who posted. I will do a test shot later and fingers crossed that's it

 

[Dan Fromm]

If your Graphic has a factory-installed fresnel, it should go in front of the glass (lens side), circular ridges facing the glass. If it has an after-market fresnel, it should go behind the glass (photographer side), circular ridges facing the glass.

Are you sure you reassembled the gg and fresnel as they had been?

 

[mopar_guy]

It is also possible to have the fresnel correct and the ground glass reversed.

 

[10speeduk]

If your Graphic has a factory-installed fresnel, it should go in front of the glass (lens side), circular ridges facing the glass. If it has an after-market fresnel, it should go behind the glass (photographer side), circular ridges facing the glass.

Are you sure you reassembled the gg and fresnel as they had been?

Dann Fromm, thankyou so much for this help. It turns out it was an aftermarket type. With your instructions working perfectly!