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by Glenn NK on Fri Jun 08, 2012 3:34 pm
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I'm trying to find a thread/post from within the past year or so wherein someone on this forum outlined a method of obtaining the correct tilt for a flat landscape (without the use of tilt tables - which are a nuisance).

As I recall, the method consisted of focusing at infinity, then using LV at max magnification, the foreground was brought into sharp focus using the tilt. The method avoided the use of tables.

Glenn
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by E.J. Peiker on Fri Jun 08, 2012 3:40 pm
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See this article in the section titled Focusing :)
http://www.luminous-landscape.com/tutor ... g-ts.shtml
 

by Glenn NK on Sat Jun 09, 2012 1:09 am
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I found it (by Royce Rowland). He was commenting on an image I had posted in the Landscape forum 06 Nov 2010. In part he said:

"I looked at the high res file. I think the distance is slightly not quite in focus. I can't tell what camera body you're using, but if you have a live view capable body I recommend using it dialed up to 10X view to nail infinity focus first, with the TS-E centered out -- no tilt or shift. Get your baseline exposure and focus first, then shift to compose, and finally tilt for DOF -- again using live view @ 10X to determine how much tilt is needed to bring the foreground into the range of DOF at your selected aperture.
"


This method he describes (and which I've been using) does not require any charts or calculations for the Tilt angle. Virtually all references describe the Scheimpflug principal in some detail. It's a good concept to master, but in the field with the sun setting fast, measurements and charts can be a bit of a hassle.

What I had done with the image submitted was obtain infinity focus, then shifted, then using LV, tilted to get the FG into focus. Mistakenly, I hadn't checked infinity focus again, and used f/3.5 (wide open), which accounted for the lack of DOF he pointed out. As I recall, I used f/3.5 as a test to see what this lens and technique could do.

Glenn
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by richard bledsoe on Sat Jun 09, 2012 9:54 am
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Glenn,

I think you may be trying to over simplifying the focusing process. Here is a quote from the link below, it helps to understand the tilt process.

"The reason focusing can become so difficult is because the focusing distance and the amount of tilt do not independently control the focus plane's location. In other words, changing the focusing distance changes the angle of the focus plane in addition to changing its distance. Focusing can therefore become an iterative process of alternately adjusting the focusing distance and lens tilt until the photo looks best." http://www.cambridgeincolour.com/tutori ... enses2.htm
 

by Glenn NK on Sat Jun 09, 2012 1:00 pm
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Lately I've been using the iterative process.

Glenn
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by Tom Robbins on Sat Jun 09, 2012 8:23 pm
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Glenn NK wrote:Lately I've been using the iterative process.

Glenn
Me too. Focusing at infinity is occasionally difficult, examples include moving water and reduced contrast due to fog and etc. In these instances I'll start with a modest amount of tilt and focus on something in the middle of the frame, and then fine tune the amount of tilt and focus until both the foreground and the middle are in focus. At that point elements in the background (infinity) should also be in focus.
 

by Glenn NK on Sun Jun 10, 2012 12:19 am
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Tom:

I mentioned this method on FM, and got blank stares. No one seemed interested in even thinking about it let alone trying it. A bit frustrating - whereas here on NSN (where I learned about it), people actually use it -successfully. Kudos to NSN. Another of the good reasons I took out a lifetime membership to NSN.

Glenn
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by DOglesby on Wed Jun 13, 2012 10:52 pm
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So, once you focus you can adjust tilt and shift without having to refocus using the focus barrel? i.e. focus with lens centered (i.e. unshifted, untilted) then tilt and shift until you get the right focus you are looking for?
Cheers,
Doug
 

by Glenn NK on Thu Jun 14, 2012 12:15 am
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DOglesby wrote:So, once you focus you can adjust tilt and shift without having to refocus using the focus barrel? i.e. focus with lens centered (i.e. unshifted, untilted) then tilt and shift until you get the right focus you are looking for?
That's pretty well it. For the image I posted at: http://www.naturescapes.net/phpBB3/view ... nity+focus

The camera was focused at the shoreline to the right of the image which although not infinity, was likely far enough to effectively be infinity. The horizon was quite hazy and not a good target.

Then (carefully without touching the focus ring), I shifted to frame the image, and tilted to get the FG in focus (the pebbles as I recall). On this shot, I did not check infinity focus again - although I could have focused on the waves.

I'm still not sure if re-checking infinity focus is required (other than to be sure the focus ring hasn't been moved accidentally). Also, I wonder if one can't just tilt the entire camera and lens to achieve framing, then use lens tilt to achieve focus close in. Royce, are you reading this?

On this image, the lens was at f/3.5 (wide open), as it was primarily a field test of the lens and tilting to see how sharp it would be across the plane of the rock and water (the rock is not as flat as the ocean). Other than the lower left corner that Royce pointed out, I was reasonably happy with the results (it was a piece of concrete that was sticking up "out of plane" so couldn't possibly be sharp at this aperture).

I'm going to be using this lens (and a 5DII) fairly extensively this July on a road trip through BC, Alberta and Sask. There are some demanding features in the Rockies, and AB and SK will be a good test also as the prairie offers many flat planes with texture (grain and grass fields) for sharpness tests.

Glenn
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by Marshall Black on Thu Jun 14, 2012 2:39 am
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DOglesby wrote:So, once you focus you can adjust tilt and shift without having to refocus using the focus barrel? i.e. focus with lens centered (i.e. unshifted, untilted) then tilt and shift until you get the right focus you are looking for?
I think it might be worth checking the focus as well as using tilt to change the focal plane, especially when you are using the focus point at infinity. I simply don't feel you can pick a focus setting and just use tilt to get everything in focus, there are more complex things happening with these lenses when tilt is applied, you should need to check and adjust focus as needed. Then check, focus, tilt, check, focus, tilt, etc..
I have the 24mm II and 90mm TSE lenses. I've had the 90mm for 19 years now, and have found the following techniques have given me the most consistent results. I know some will find it easier to work in different ways, but some might find my methods useful.
Before digital came along my method was to frame up the subject, then focus close or around a third into the frame. Then apply tilt checking the viewfinder (obviously), pushing the tilt until the background became out of focus, i.e. overdoing the tilt. Then I'd check if the close/mid focus was OK and adjust accordingly. Then I'd pull back the tilt to get the background sharp in stages. Check focus across the frame, tweak a little bit more until happy, and lock the tilt. Then press DOF preview and check for tall objects such as bushes, rocks, trees.
I will still use this method first with digital, but can now use live view also. Live view often leaves me with a nice feeling, a confirmation that everything is good. With digital, before live view, I used to review a shot frame as this would show the result was good or had problems. Difficult to be sure on the tiny lcd on the 1DII!
Why not try this method too? See if it works for you. Maybe try with an even plane subject for practice, then try on more complex (bumpy plane) subjects.
I need to set off to work, but will re-read this later to see if I've missed something, or made it tricky to understand.
Cheers
Marshall
 

by Tom Robbins on Thu Jun 14, 2012 4:31 am
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Marshall, very well stated. Live view and lots of practice will help establish one's method. I had to send in my 5D MKII off to Canon repair to get its processor replaced a couple months ago, and quickly rediscovered just how difficult getting things dialed in through the viewfinder is while using my backup 5D MKI. The 2x view using an angle finder helped a little, but it was a very poor substitute for LV.
 

by DOglesby on Thu Jun 14, 2012 8:28 am
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Thanks guys. I can't imagine what it would have been like (and the skill required to do it right) before digital.
Cheers,
Doug
 

by Darren K on Thu Jun 14, 2012 1:08 pm
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For clarification, always focus far, tilt near, then repeat as necessary. In nearly all instances, after your initial tilt, you will find your far focus point will now be out-of-focus, thus requiring the process to be repeated until both are sharp. It will be readily apparent in most scenes; in your beach shot example, Glenn, it may have been a little less noticeable.

For your upcoming scenario of shooting mountains, say you had flowers/rock right in front of you and a mountain in back. You will want to focus midway up the mountain, as opposed to the summit, as you'll want to keep your focus plane in the middle of everything you want in focus. The area above and below that line will be brought into (apparent) focus by the aperture. If you were to focus on the summit of a mountain, you will have a lot more area below your plane that will require an even smaller aperture to bring in focus.

A second example is if you were on a canyon rim of a deep canyon and wanting to shoot an intimate landscape without the sky above the opposite rim. You would want to put the focus point midway down the opposite canyon wall; if you were to focus on the opposite rim, the canyon bottom area will be even more horribly out-of-focus. So, always keep your focus plane in the middle of everything you're wanting sharp.

I'm not sure if the above helped, or if it even makes sense, but I throw that out there since you're new to it. It is not uncommon for me to have to restart from neutral one or more times whether using a 4x5 or a TS-E lens. Some scenes tend to give me more problems than others. I suspect I am not alone in that regard.
 

by E.J. Peiker on Thu Jun 14, 2012 1:16 pm
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Darren's tips are VERY important. Doing it any other way results in wasting available depth of field in the tilted axis resulting in needing a smaller aperture and negating some of the benefits of shooting with a tilt lens.
 

by Marshall Black on Thu Jun 14, 2012 2:56 pm
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Back from work with some great useful stuff added by others. I also thought of a few things to add, and will address them as follow up from some of Darren K's post.
Darren K wrote:For clarification, always focus far, tilt near, then repeat as necessary. In nearly all instances, after your initial tilt, you will find your far focus point will now be out-of-focus, thus requiring the process to be repeated until both are sharp.
Maybe it's me, but I prefer using focus near, tilt far. I suspect this could be something to do with my years of using the 90mm on film and without live view. Or perhaps this is an easier technique for the 90mm? I do have more trouble with getting the whole scene right with the 24mm (sometimes I don't bother with tilt and just use the greater DOF afforded by the 24mm) so I will definitely be trying this out ASAP. I am genuinely surprised that I find the 24mm harder to work than the 90mm, surely is should be easier?
Either way, it seems generally agreed that you will need to repeat the tilt/focus process to get it right.
Darren K wrote:You will want to focus midway up the mountain, as opposed to the summit, as you'll want to keep your focus plane in the middle of everything you want in focus. The area above and below that line will be brought into (apparent) focus by the aperture. If you were to focus on the summit of a mountain, you will have a lot more area below your plane that will require an even smaller aperture to bring in focus.
This is one I was coming back on.
Absolutely, you will probably be best keeping in mind that your DOF is now contained in a wedge shape, and where you place the centre of the wedge is very important. To try before you go, find a subject like a tree in a field (or a road and building), and see if you can establish the positioning of that wedge to get the top of the tree and the field in focus. Much harder to achieve than it sounds.
Darren K wrote:It is not uncommon for me to have to restart from neutral one or more times whether using a 4x5 or a TS-E lens. Some scenes tend to give me more problems than others. I suspect I am not alone in that regard.
This is another I was coming back on. You are certainly not alone Darren, and I bet there are others.
You can end up in a kind of stalemate situation with the tweaking, no matter what you do it just won't work. Go back to zero and start again. It's amazing how you can start again and hit the spot straight off. Really, keep this in mind if you're starting to go mad with tweaking stuff!

OK, last point.
I'm not sure, but I think that live view shows more sharpness and/or DOF, and I think this is stated in the manual for the 5DII somewhere. I have slavishly got everything right in live view, checked and rechecked, then found on the computer that the image doesn't reach my memory of how sharp I had got the shot in live view. I think the only way I can test this is to plug the camera into the laptop and do a comparison when shooting. What worries me is that if I'm right I need to find some kind of formula, say add one or two stops of DOF, to adjust for this. I certainly don't want to be shooting with the laptop plugged in all the time!
Maybe i should start a new topic on this, as I don't remember seeing this being mentioned anywhere before.
Anyway, hope all this helps. This has ended up as a really useful topic IMHO.
Cheers
Marshall
 

by Darren K on Thu Jun 14, 2012 3:53 pm
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Marshall Black wrote:Maybe it's me, but I prefer using focus near, tilt far. I suspect this could be something to do with my years of using the 90mm on film and without live view. Or perhaps this is an easier technique for the 90mm?
It can be done either way. I believe it's simply far more common to use the focus for the furthest point, which is why I listed it that way.
 

by Glenn NK on Thu Jun 14, 2012 8:09 pm
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My personal thanks to Darren and Marshall. :) :)

Excellent comments that will be copied and pasted and read.

Glenn
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