Chamonix 45-F2: scheimpflug for landscapes?

[Bernice Loui]

From the Ebony guide..


Another reference to why chronic f22 or smaller exposure aperture is not a good habit. Use an exposure aperture no smaller than absolutely needed. Similar/identical note is found in the Sinar user guides and others.. This why learning how to properly apply view camera movements is SO important as it is one of the primary reasons to use a view camera.

Controlled selective focus is an extension of using camera movements at full to large lens exposure apertures.. A feature specific to using a view camera..
Or, putting the point/plane of lens focus precisely where the image maker intends the point/plane of focus in the image needs to be.

Horseman had "focus plane rise" as a feature on some of their L series monorail cameras. Idea being once tilt has been applied and set, the image can be re-framed as needed using the focus plane rise feature on the front or rear standard.

"Easy Reframing with Focus Plane Rise (F.P.R.)
Reframing after focusing was quite a chore in the past --- every readjustment of the frame area necessitated refocusing, which in turn required reframing, which in turn... But now, the Horseman "focus plane rise" feature permits reframing after focusing in one easy step. The camera back can be raised and lowered along the focal plane. By the same token, the front can be moved along the lens plane. Focusing is not disturbed by these operations, making last second frame adjustments a quick and painless process."
https://www.bhphotovideo.com/c/produ....html/overview

Previously discussed on LFF:
https://www.largeformatphotography.i...s-Re-Movements

https://www.largeformatphotography.i...ovements/page2

If the field folder does not allow that "rise" movement on both front & rear standards, this could be a limitation..


If the guide lines are used to the point of habit to aid in setting those specific camera movements, there is a possibility of affecting the image composition due to the limiting nature of always using those guide lines to aid in setting camera movements. Awareness of this limitation can go a ways to prevent this.



Bernice

Here's Ebony's guide to asymmetrical movements. The principles apply to any camera with asymmetrical movements. https://www.mr-alvandi.com/downloads...el-cameras.pdf .

Doremus

I read through that. Thanks. One comment. Sometimes the far object isn't on the far line at the bottom where the axis is. So I do a rise or drop on the front standard to line the subject on the axis line and focus. Then I return the front standard to where it was originally compositionally and do the asymmetrical tilt on the read for the front subject. Someone confirmed that the rise and fall won't change the focus or tilting results.

[Alan Klein]

Alan,

You can use front rise/fall to position a far object on the axis line as long as you haven't tilted it beforehand. That way, the lens plane the same distance from the axis line on your ground glass regardless of the lens' vertical position. It should be obvious that if you tilt and then use rise/fall, the lens plane's position will move forward or backward relative to the axis line, which you don't want.

Alternatively, you can just forget the axis line and use the iterative method of applying rear tilt, i.e., focus on the far, tilt till the near and far are equally unsharp, refocus on the far, check the near and repeat if needed.

FWIW, center axis tilts have the same shortcoming to a greater extent: you can't always get a reference point on your desired plane of sharp focus to fall on the axis line. With base tilts, there's never a reference point that falls on the axis (since it's below the ground glass!), so it's really worth learning the iterative method for those times when your axis markings aren't helping any.

Best,

Doremus

I didn't know that. So although I have checked the focus after moving the front standard up or down and it looked focus, I can see that even if it;s initially tilted just a little, using this rise and fall could throw off the focus. What if I use rise and fall on the rear standard first to line up the axis line on the far subject? ___________________?

The more I try to finesse asymmetrical operation, I think I'm getting to the point that I should just learn the iterative approach. A few questions about that.

When you say tilt until both are out of focus, how much? ___________? Do you tilt past the focus point or before? __________________?

What's the best procedure for this multi iterative approach? ____________________?

Anything I should be aware of regarding rise and falls and other stuff when doing it?________________?

[Doremus Scudder]

This is beginning to look more and more like a test... I hope it is helpful to you and others too. So, here goes. Let me know if I pass

... I can see that even if it's initially tilted just a little, using this rise and fall could throw off the focus. What if I use rise and fall on the rear standard first to line up the axis line on the far subject? ___________________?

If you reframe by using the back rise/fall after applying back tilt, you will need to refocus. Be aware that if you use rise/fall on the same standard after you've applied tilt, you're changing focus. But, since you've already applied the tilt, your tilt shouldn't need adjusting. So just reframe the image using rise/fall if you need to and then refocus, making sure your original points are in focus. If you can reframe using rise/fall on a standard that hasn't been tilted, then use that (e.g., use front rise with the front standard in zero position to get your focus point on the axis line, apply tilt, reframe using front fall).

The more I try to finesse asymmetrical operation, I think I'm getting to the point that I should just learn the iterative approach. A few questions about that.

When you say tilt until both are out of focus, how much? ___________? Do you tilt past the focus point or before? __________________?

What's the best procedure for this multi iterative approach? ____________________?

Okay... When you get one focus point sharp and the tilt toward the other, the first point goes out of focus and the other begins to get sharper. Tilt until they look about the same; it's not that critical. The closer a point is to the tilt axis, the less it's going to change focus in relation to the other point. Just do a rough first tilt, then refine. But, you don't want to tilt past the point where the second point is sharp and then starts to go out of focus. So, don't "tilt past the second focus point" (to use your words), but stop before it gets sharp. Then refocus the first point, check the second and repeat. It may take two or three iterations. That's really all there is to it.

If you do tilt past the second point, or if you've tilted in the wrong direction (it happens sometimes), then you need to tilt in the opposite direction when refining. To prevent this, you can do a simple check: Focus a point at the bottom of the ground glass (which is normally the top of scene). This is point one. Look at point two (top of ground glass/bottom of scene) under the loupe and tweak focus in one direction only just a tiny bit while watching point two (I like to focus nearer; i.e., make the bellows longer). If the second point gets a bit sharper, then you need to tilt the same direction (i.e., if you tweaked focus to make the bellows longer, then you need to tilt the back backward or the front forward). If the second point gets less sharp, then you need to tilt in the opposite direction.

Anything I should be aware of regarding rise and falls and other stuff when doing it?________________?

If you use rise/fall on the same standard after the tilt has been applied, you will need to refocus as described above. Usually the amount of rise/fall used for reframing is small, so refocusing isn't hard. The real use of front rise/back fall is for architectural work where you want to preserve vertical parallel lines and include the top of the building. Then the camera back needs to be plumb. Any tilting needed in this case needs to be front tilt. FWIW, I use front tilt a lot in architectural work; just a tiny bit is often all it takes to really optimize depth of field, especially if there's a lot of foreground in the frame.

Don't use the tripod head tilt to reframe after you've applied tilt with the camera; it will throw things off.

Visualizing what you want to do with the PoSF before you start applying movements is really helpful. Find the points you want the plane to intersect first, then tilt.

Best,

Doremus

[Rod Klukas]

The rules are the opposite: For Base tilt, Focus far and tilt near.

For Axis tilt for near and tilt far.

Remember: Far is always tallest nearest of far objects. If, for example, you were photographing across a meadow, with some tall trees and 100 meters on the other side. Through the trees a mountain is visible, but shorter as you view the ground glass, than the trees. Then, the top of those trees is your far, for using tilt.

If you have front and rear focus, use the back focus to first focus the trees. Next use the front tilt to clear up, sharpen, the foreground. Now recheck the tree tops and tweak. Go back and forth as many times as needed to get your near and far sharp. Having a MM focus scale to show focus movement helps the next part. Some cameras have them, but they are available in adhesive tape to add to other cameras.

Assume you do. On my Arca it does have a scale. So after doing the above, note the focus position on the ruler/scale. Say it was on 32mm. Next search the ground glass between the tree tops in our example and below down to the foreground object you used. What is the softest/least sharp object? In this example, probably the base of the trees. Now focus the base of the trees. Say you moved from 32 to 35mm. So you moved 3mm. For a 4x5 multiply the total displacement by 5. 5 x 3 = 15. Change the. unit to apertures and you have a minimum aperture of F 15 to have all sharp. One last step: refocus 1/2 way between the near(32) and the far(35)--to 33.5 and you are done. Meter for the first shutter speed combo, that works with at least F15, in our example, and set it and expose.

It works.

(For 6x9 use 7.5 as the multiple, 5x7 use 3.5, 8x10 uses 2.5)

Hope some people use it and it helps them.

Rod

[Alan Klein]

The rules are the opposite: For Base tilt, Focus far and tilt near.

For Axis tilt for near and tilt far.

Remember: Far is always tallest nearest of far objects. If, for example, you were photographing across a meadow, with some tall trees and 100 meters on the other side. Through the trees a mountain is visible, but shorter as you view the ground glass, than the trees. Then, the top of those trees is your far, for using tilt.

If you have front and rear focus, use the back focus to first focus the trees. Next use the front tilt to clear up, sharpen, the foreground. Now recheck the tree tops and tweak. Go back and forth as many times as needed to get your near and far sharp. Having a MM focus scale to show focus movement helps the next part. Some cameras have them, but they are available in adhesive tape to add to other cameras.

Assume you do. On my Arca it does have a scale. So after doing the above, note the focus position on the ruler/scale. Say it was on 32mm. Next search the ground glass between the tree tops in our example and below down to the foreground object you used. What is the softest/least sharp object? In this example, probably the base of the trees. Now focus the base of the trees. Say you moved from 32 to 35mm. So you moved 3mm. For a 4x5 multiply the total displacement by 5. 5 x 3 = 15. Change the. unit to apertures and you have a minimum aperture of F 15 to have all sharp. One last step: refocus 1/2 way between the near(32) and the far(35)--to 33.5 and you are done. Meter for the first shutter speed combo, that works with at least F15, in our example, and set it and expose.

It works.

(For 6x9 use 7.5 as the multiple, 5x7 use 3.5, 8x10 uses 2.5)

Hope some people use it and it helps them.

Rod

How would you describe your methods for cameras with asymmetrical tilt, Rod? The line on the axis on the bottom is focused on the far and then you tilt the rear standard back to get the near in focus. How then do you subsequently apply your method for determining aperture and moving the focus?

[Rod Klukas]

By the way, to have the corners close to the center in terms of sharpness, you need also to shoot standard lenses--135mm and longer in most cases-- at least 2 stops down from wide open.

For Wide angle lenses, due to curvature of field, you need to stop down at least 3 stops for even full frame/sheet coverage.

Hope this helps.

Rod

[Rod Klukas]

Focus far and tilt near is only correct for Base tilt, and Arca-Swiss Orbix tilt.

Axis tilt cameras should use the rule: Focus near and tilt far.

Also tilt has issues shooting below your feet. This is beacause the far plane of apparent focus is above what you can see. So the items below your feet will fall out of focus. So no tilt really for canyon shooting or, from one building to others in the city.

Contact me if you would like a quick cheat sheet on this.

Rod

[Rod Klukas]

You will still have a middle that may be soft after using rear tilt. So after attaining near and far focus points. Hunt the middle of your glass for the soft spot and before you move check the start point. Then refocus on the softest area in your image. Note new position. For 4x5 multiply the total displacement by 5, and the number is your minimum aperture. Now refocus back to 1/2 the total displacement. All set.

[Doremus Scudder]

Rod,

I have to disagree with your assessment about applying axis (and asymmetrical) tilts. With center axis tilts, it's usually easiest to find something on the axis line, i.e., in the center of the image, to first focus on and then tilt to get either end in focus. With asymmetrical tilts on most cameras, it is usual to use the bottom reference line first, which means finding a far object to focus on in most cases, and then tilting to bring the near in focus. Ebony, Chamonix and even Sinar asymmetrical tilts are designed this way.

At least the above is what I find easiest.

Best,

Doremus

[Alan Klein]

You will still have a middle that may be soft after using rear tilt. So after attaining near and far focus points. Hunt the middle of your glass for the soft spot and before you move check the start point. Then refocus on the softest area in your image. Note new position. For 4x5 multiply the total displacement by 5, and the number is your minimum aperture. Now refocus back to 1/2 the total displacement. All set.

why 1/2 between the soft spot and the far Focus point? Shouldn't it be to 1/2 between the soft focus point and the near focal point due to the 1/3 2/3 aperture relationships and depth of field?