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gabain
19-Dec-2019, 03:48
Hello fellow photographers,

I hope you may have some suggestions how to use a lens shade.

I have been using a lens shade with a Linhof Technika.
I was using a 500mm lens, composed the picture with aperture wide open and focused to infinity, then added the lens shade, image was clear and shade did not seem to be in the way.
I stopped down the lens F64 and took the shot.
The lens shade perfectly cropped the image to square format. Needless to say that was not the expected result.
I assume it has to do with the different focus points - one very close and therefore out of sight and the other one far away in focus.

My question is:

Has any of you used the lens shade / compendium from Linhof and what is your strategy to use it without getting it in the way?

Thanks

Klaus

Bob Salomon
19-Dec-2019, 04:07
Use the compendium made for the Technika. Lens hoods do not belong on fully adjustable cameras.

gabain
19-Dec-2019, 04:21
Hello Bob,


I do have in fact a lens hood from Linhof made for the Technika.

I figured If Linhof ist make a lens hood for their cameras there must be a technique to use them right.


Sent from my Pixel 4 XL using Tapatalk

Huub
19-Dec-2019, 05:23
When i doubt i look into the lens from the frontside and check if i can see all the edges and corners of the ground glass. When i can see them with some margin, i know i am right.

gabain
19-Dec-2019, 08:01
Thanks for the reply Huub,
I know this work to check extreme movements but would this work as well with the compendium considering it is upfront the lens. I will certainly give it a go.

Sent from my Pixel 4 XL using Tapatalk

Andreas
19-Dec-2019, 08:48
This is one of the reasons many groundglasses are clipped at the corner; the aerial image tells you if movements are too extreme (not all blades of the diaphragm are visible) or if the shade is in the picture. It is also a good way to adjust the shade as tightly as possible.

Bernice Loui
19-Dec-2019, 09:19
If the set up is used outdoors, consider using the film holder dark slide, hat, sheet card board or similar to cast a shadow on the front of the lens. This is often more than enough to reduce flare that can lower image contract. Only times I'm willing to use anything more than the film holder dark slide is in a very controlled lighting and subject set up. In this case, the Sinar 4-way adjustable curtain shade on a extra bellows and front standard properly set up works really good, but takes time and care to set up.

~Why the image taking aperture of f64?



Bernice

Vaughn
19-Dec-2019, 11:29
This is one of the reasons many groundglasses are clipped at the corner; the aerial image tells you if movements are too extreme (not all blades of the diaphragm are visible) or if the shade is in the picture. It is also a good way to adjust the shade as tightly as possible.

This is what I do, also. I prefer GG with cut corners. I can use the aerial image to see exactly what is in the corners. There are many times I can not stand in front of the camera to check from that direction (Huub's suggestion).

Glare can come from many angles -- and can be worse on bright foggy days with glare coming into the lens from all angles. Or glare can come in strongly from other directions other than the light source (off snow or light granite on the ground in front of the camera, for instance). I'll 'build' a shade by putting the darkslide on top of the bellows and extended over the lens a ways -- then droop the darkcloth over the camera and the darkslide -- still not good for light reflecting off the ground towards the lens, but does a nice job otherwise.

Doremus Scudder
19-Dec-2019, 11:46
Klaus,

The obvious answer is to check for vignetting at the taking aperture; i.e., stop down first and then check. Checking the ground glass at the smaller aperture should show you if the lens hood is intruding into the image. If the ground glass is too dark, use the techniques described above: checking the corners from the front (at taking aperture!) and/or checking corners from the back. Whether the vignetting is caused by extreme movements or the lens hood makes no difference.

FWIW, I sometimes remove the camera back and check sight lines from the four corners, making sure I can see all of the aperture (stopped down first). That works too.

FYI: if you are viewing with your aperture wide open, you can get an image in the corners when the aperture is only partially vignetted. This image is dimmer, but often hard to distinguish from the rest of the image. The part of the image that reaches the corner is cast from the opposite side from where the vignetting is taking place. So, when you stop down, you reduce the size of the aperture circle to where it is completely blocked and you end up with very visible vignetting. (Hope that makes sense...)

Best,

Doremus

ic-racer
19-Dec-2019, 12:18
The obvious answer is to check for vignetting at the taking aperture;
This is in all the beginner books. Usually dealing with 35mm and stacking filters and lens hoods, but as Doremus points out, it applies to LF too.

cowanw
19-Dec-2019, 13:12
Not sure if your Technika supports a 500mm lens. The Master Technika's spec say 430 mm is maximum length at infinity. At f 64 I would not have expected vignetting to a degree that "perfectly cropped the image to square format". I wonder if something else is going on.

Arne Croell
19-Dec-2019, 13:19
Not sure if your Technika supports a 500mm lens. The Master Technika's spec say 430 mm is maximum length at infinity. At f 64 I would not have expected vignetting to a degree that "perfectly cropped the image to square format". I wonder if something else is going on.

I use a Nikkor T-ED 500mm on my Master Technika. Works fine.

gabain
19-Dec-2019, 13:20
I do consider changing my ground glass since the coreners of the Linhof are not clipped.
Thanks for your remark.

gabain
19-Dec-2019, 13:21
I can confirm as well. I am also using the T-ED 500mm.

gabain
19-Dec-2019, 13:23
Klaus,


FYI: if you are viewing with your aperture wide open, you can get an image in the corners when the aperture is only partially vignetted. This image is dimmer, but often hard to distinguish from the rest of the image. The part of the image that reaches the corner is cast from the opposite side from where the vignetting is taking place. So, when you stop down, you reduce the size of the aperture circle to where it is completely blocked and you end up with very visible vignetting. (Hope that makes sense...)

Best,

Doremus

Hi Doremus,

makes all perfect sense to me . Thanks for taking the effort.

Klaus

Mark Sawyer
19-Dec-2019, 14:37
If the vignetting is on one side of the negative only, I'd suspect bellows sag over the shade. If it's on both edges, yep, the shade. But with the narrow angle of view of a 500mm on 4x5, I'm surprised it vignetted from the shade.