My second 8x10

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soupdragon

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Sorry about the samey subject but it is my test bed for new toys.
Techy stuff: Tachihara field stand 8X10, Schneider 240 APO symmar, Kodak Portra 160, home dev in Cinestill CS41 using a Stearman tank, Epson V850 scanned at 2400 dpi.

2nd.JPG
 
I have an issue that I'm sure somebody here can help with.
Whilst it's difficult to see from the image, the point of focus is sharp (the windowed section of the tower) but the top and bottom of the tower are not in focus.

I intentionally did not use any movements although the camera was pointed slightly upwards.

I was hoping the structures at sea level and the top of the tower would have been in focus at f32.
What did I do wrong?
 
A lens aberration seems unlikely.
The verticals appear almost vertical so the back was close to vertical. The most likely cause is some unnoticed tilt on the front standard, added to the upward tilt of the whole camera. The plane of sharpness would then extend from in front of the tower at the top, through the windows and then backwards towards the harbour wall (?) in the background.
Is the lens quite heavy? Could either of the standards have been a little bit loose? I’m not suggesting any lack of diligence on your part, but these are the questions that should be asked, rather like TV cops asking where everyone was at the time of the murder.
 
David M said:
A lens aberration seems unlikely.
The verticals appear almost vertical so the back was close to vertical. The most likely cause is some unnoticed tilt on the front standard, added to the upward tilt of the whole camera. The plane of sharpness would then extend from in front of the tower at the top, through the windows and then backwards towards the harbour wall (?) in the background.
Is the lens quite heavy? Could either of the standards have been a little bit loose? I’m not suggesting any lack of diligence on your part, but these are the questions that should be asked, rather like TV cops asking where everyone was at the time of the murder.
Click to expand...
I have to admit, I'm not sure the front and rear standards are parallel when using the engagement slots.
Do you think some front tilt would have overcome this problem?
 
I wasn’t there of course, but it does seem reasonable to check with the loupe and make adjustments. As you say, using some front tilt. Sometimes it’s necessary to choose the best compromise possible. In this case, I suppose you’d want to have the whole of the tower sharp and then decide what‘s acceptable elsewhere.
It’s certainly a spectacular scene.
 
I take it that you've viewed the negative with a loupe to confirm that it's a film and not a scanning issue?

From what you describe, 'a part in the middle in focus with both top and bottom out of focus', 2 things spring to mind;

1. The film being curled or curved and not sitting flat in the film holder at the time of exposure. Possible but perhaps not so probable.

2. The front standard and rear standard tilted/situated in opposite directions. (The same can happen with opposing swing movements.)
This should be visible when viewing the ground glass with a loupe and can be used to creative effect, if, you only wish to have 'a slither' in focus.

When you set-up and 'zeroed' the camera, you noticed that the camera was tilted up slightly. So then I presume you tilted both the front and the rear standards so they were parallel with the subject plane. This means that your camera is now plumb, with a little bit of indirect rise, and everything should be in perfect focus. See image.
Screenshot_20241025_024655_Firefox.jpg
 
What holder are you using in the scanner, the negative holder in the 850 is not good, I bought and use a Epson wet plate holder and use it dry with a piece of AN glass on top to keep the neg flat.
Martin Henson has a very similar setup on YT.
 
After much head scratching the problem transpires to be operator error.

I could not find the correct manual for my camera so just unfolded it in the same manner as my Toyo 45.
On closer inspection I found there is a slot in the verticals of the front standard. Looking at the brass assembly that holds the lens board, there is a tang that should be fitted to the slot before cenetring the rise.

This is what was causing the front and rear standards to be not parallel.

I feel like and idiot now.
 
We’ve all done something very similar. As Flack says, it’s how we learn.
Thank you for sharing your adventures with us.
 
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