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View Full Version : Fujinon SWD 90mm f5.6 on 5x7" vignette - too wide lens for Lee wide angle adapter?



tsiklonaut
5-May-2019, 03:22
Made first shots with my Rittreck 5x7" with Fujinon SWD 90mm f5.6 and when I used some reasonable motion (not extreme) there was LOTs of vignette, unbareable.

On my medium format camera I never could make the same Lee filters (which I love!) with the same wide angle adapter to vignette, even with the widest of the lenses, but now in 5x7" 90mm LF it vignettes too easily. Note the special wide angle adapter mounts the holder the closest to lens as possible.

Only when shooting straight with no lens movement there is (barely) no vignette. I have 2 filter slots + a very thin circular polariser mounted on top. This is clearly too much for SWD 90mm on 5x7" to handle. I took away one filter slot (thus leaving just 1 filter slot on the Lee hollder) then I can do some very small movements, but barely livable like this.

I wonder if it's just way too wide lens to use filters on OR it is the speciefics of Fujinon's SWD 90mm f5.6 with HUGE front element (82mm filter thread) that is on the limit for the 100x100mm square filters?

Anybody else have the same experience with Lee wide angle adpater on very-wide lenses on their LF?

slavatokar
5-May-2019, 04:16
This lens just dont have enough coverage, i tried same combination, Rittreck 5x7 and SWD 5.6/90, with plain screw-in filter, movement very restricted, useless for me
https://live.staticflickr.com/871/27597915608_ea92b7e91b_z.jpg (https://flic.kr/p/J3JwPb)Scan-180414-0002 (https://flic.kr/p/J3JwPb) by Вячеслав Филатов (https://www.flickr.com/photos/115618176@N08/), on Flickr

Pere Casals
5-May-2019, 04:51
then I can do some very small movements, but barely livable like this.



Max rise (landscape) at f/22 is 21mm. If the lens is not stopped you have less... https://www.largeformatphotography.info/lenses/LF5x7in.html

So you should frame with the lens stopped, if you frame with the lens wide open then you may not use all the circle, because you don't see the circle growth for the taking aperture if you frame at f/5.6.

It is quite easy to see if the adapter casts a shadow, just shift the back until you see the circle bundary and then place the filter on the lens... Also consider that the circle grows when you stop the lens and when you give bellows to focus close subjects. You should check if the filter limits the circle at the different apertures.

Bernice Loui
5-May-2019, 07:36
Possible to post that specific image to get a rough idea of what has happened?


Bernice

Leigh
5-May-2019, 08:03
The image circle of the 90 SWD is 236mm, while the diagonal of 5x7 is 218mm.
That would allow very small movements with the lens and no filters.

- Leigh

Bernice Loui
5-May-2019, 09:17
OK to use a 105 degree 90mm lens on 5x7, but there is not much allowance for camera movement. The Schneider 90mm Super Angulon XL has a larger image circle of 259mm @ f22 which is better if more camera movement is required.

More difficult is the light fall off at these extreme angles, in some images the light fall off is OK, other images total disaster. Adding the proper center filter can help a LOT.

Filters are fine long as they are larger than the front element. In this case, using a step ring from 82mm to no smaller than 95mm close to the front element or better yet 105mm. Alternative is to put the filter on the rear element of the lens. This often causes focus shift which is easy to compensate for if they filter is in place then image focused-set up as usual. If the square filter holder is any signifiant distance from the front element, it can cause an image cut-off problem due to filter holder margins required to support a 100mm square filter and attachment to the front of the lens.

As previously mentioned, all this is conjecture and speculation until an image of the problem in question can be assessed.



Bernice



The image circle of the 90 SWD is 236mm, while the diagonal of 5x7 is 218mm.
That would allow very small movements with the lens and no filters.

- Leigh

tsiklonaut
7-May-2019, 03:29
Cheers guys for the info, makes lots of sense but I didn't expect the optical filter to factor in vignette that much. I guess 150mm filter system would be better suited for the 90mm SWD with such a large front element.

Here's one example of rather extreme vignette with quite a front rise (roughly over 30mm) with 100mm filter stack in front on a WA adapter:

191041

191042

Lessons learned:

No to very little movement with 5x7" back as pointed out with image circle of this lens.

Filters even with WA adapter will steal even more space from the corners.

Had to crop alot to make it a usable:

http://yhelteljel.ee/wp-content/uploads/2019/05/SMX5409_s.jpg


Will use it more with the 4x5" rotating back, lots of more movement.

Bernice Loui
7-May-2019, 07:28
This filter set up not gonna work with 30mm of rise applied. As exampled, part of the filter holder will be involved with the image. The 100mm square filter holder will be smaller than the 100mm square filter, add the filter holder distance to the filter and lens then apply rise or drop or shift or other camera movement produces part of the filter holder into the image. Using a lens with a larger image circle will produce much the same results, except the 100mm square filter system as the Schneider 90mm SAXL has a 95mm front filter size.

Alternatively, move the 100mm square filter system to back of the lens inside the camera bellows. This has the advantage of reducing flare due to stray light on the filter. Or do the step ring up to a larger filter size.


Bernice



Cheers guys for the info, makes lots of sense but I didn't expect the optical filter to factor in vignette that much. I guess 150mm filter system would be better suited for the 90mm SWD with such a large front element.

Here's one example of rather extreme vignette with quite a front rise (roughly over 30mm) with 100mm filter stack in front on a WA adapter:

191041


Lessons learned:

No to very little movement with 5x7" back as pointed out with image circle of this lens.

Filters even with WA adapter will steal even more space from the corners.


Will use it more with the 4x5" rotating back, lots of more movement.

Eric Leppanen
7-May-2019, 10:50
You can reduce filter holder vignetting by using a press-on filter holder, which fits over the lens barrel, rather than a wide angle adapter ring which screws onto the filter thread:

https://www.bhphotovideo.com/c/product/162980-REG/LEE_Filters_FK100_Foundation_Kit_100_4x4.html

Since your Fuji lens has an 85mm front lens barrel diameter, you would need an 85-to-100mm "doughnut" ring to adapt this holder to your lens. I offhand don't know if Lee makes anything like this (they make a 90-to-100) but SK Grimes could fabricate one for you.

This admittedly is an expensive solution. Alternatively if you are handy in the workshop you could craft a home-made version using Lee side guides.