It's a very nice shed.
It's a very nice shed.
You don't really need lens tilts for this picture. You could probably bring the foreground to acceptable sharpness using only depth of field. A very slight front tilt might give a little boost in the right direction, but that's not what's making the shed lean to the right.
If we think of the movements of an airplane, where we have pitch (nose pointed up or down), roll (wing tip high or low compared with the opposite wing tip), and yaw (nose pointed left or right of the direction of travel), then what you have in this picture is a bit of roll. I like these terms because they apply to the camera at large rather than to the movements within the camera. If the camera with all the movements zeroed is not level and plumb, then correcting the issue with movements is either more difficult than it needs to be or impossible. The only way to correct the issue I see here is with a rotating back (or a little rotated cropping).
Apply movements to adjust the projection of perspective convergence, or to adjust the focus plane. Don't apply them to correct a problem in where and how the camera is pointed.
Rick "whose garden shed will make a mockery of a bubble level--give me the grid lines any day" Denney
"I think I might just want to tilt/swing just cuz I can."
Yeah, this is where lots of people get themselves all twisted up with a view camera. (pun intended) Movements are nice to have but sometimes all you need to do is get the camera level, apply a little rise or fall to get the composition where you want it, set the appropriate aperture, take the picture and move on.
Frank....most of this is your fault!
OK...the general concensus is that movments will not fix this and probably caused this in the first place!
I will really level the big thing and stop myself from moving too much!
Rick....very good explination
Thom....I was about to send you an E mail...David here from the NO workshop
david
If you want the 3 visible vertical edges of the shed to be all parallel then the camera back has to be parallel to the shed.
I'll bet the people who built the shed made the 4 edges paralell to the pull of gravity. If you do the same with the back (make it parallel to the pull of gravity) you will be assured of success.
Manipulations to the front standard will have no effect and swing or rise/fall of the rear will have no effect.
Too many answers making a simple answer more complicated.
First rule: Tilts and swings on the back always control the shape of the subject.
Second rule: Tilts and swings on the back also control Scheimpflug (plane of sharp focus).
Third rule: Front swings and tilts also control Scheimpflug (plane of sharp focus).
Fourth rule: Tilts and swings on the front never control the shape of the subject.
Fifth rule: Perspective is changed by changing the angle of the camera to the subject. Not by adjusting the camera controls.
So. Use back movements to correct the shape of your shed.
First use a good level to level your camera to the shed.
Then use the same level to get your back parallel to the shed.
Then use that same level to make the lensboard parallel to the camera back.
Now there are no converging vertical lines.
Should you have converging horizontal lines swing the back so it is parallel to the shed and the lens so it is parallel to the back.
Want to change the plane of sharp focus? Tilt or swing the front so you don't change the shape of the subject. Need more in focus? Stop the lens down enough to get the desired DOF without going into diffraction.
IMO, either the shed or the camera is not level...or both! I would trust the grid before I'd trust a level (like light meters, finding two levels that agree is difficult). Plus most LF cameras are not big enough for a decently size flat spot to measure the level accurately. Of course, YMMD.
The only true vertical edge I see on the print is the far right edge of the shed. Starting with the standards zeroed out and the camera roughly level, I'd use front rise/fall to frame up the image like I want. Then I'd get the nearest corner of the shed to the camera vertical first (visually, not w/ a level, by tilting the whole camera to the right or left), then move the back (tilt) until the other two corners of the shed were vertical. Then toss in a little front tilt and refocusing until I got the best focus possible, then close the aperture down to get everything in focus. But that is only how I would approach it and it would work just fine and dandy for me, with very little fussing around. It took me 10 times as long to write this than it would take to do it)
Vaughn
David,
Vaughn touched on something I was thinking about. Who says the shed is level and frame is vertical? From the looks of the ground, paver stones, etc. I'm guessing the owner probably didn't level the ground when putting in the shed? Having said that, it looks like the right edge frame is more vertical than the left edge, suggesting something not exactly as it seems with the shed in terms of vertical alignment and level. Converging lines due to camera back angle would produce an effect on both left and right vertical lines of the shed I would think. Just a thought. You should obviously consider the set up of the camera (zeroing everything to start,) as suggested, but also consider your subject. ie. Tall ponderosa pines aren't all necessarily growing exactly straight up!
I also agree that tilt is not necessary, although I can understand using a smidge of front tilt if you're really interested in the grass at the very bottom. HOWEVER, what you might be missing here when using tilt when you have strong verticals is potentially losing sharp focus at the very tops of your verticals (tree tops or potentially the bottom of the fence in back, etc.). As others have eluded to (I'm just saying in different words,) is that when you have a combination of near/far AND strong verticals (tall trees, buildings, etc.) then you're basically going to fall in to a simple depth of field exercise with teenie tilt or no tilt at all.
I've yet to make this public, but perhaps this guide will help you. It's geared towards the beginner and not extremely technical, but hopefully it may shed some light for you. Please let me know what you think. And feedback from anyone else who happens to read this would be greatly appreciated.
Lon
A ruler and pencil on the ground glass side of your GG will bring the grid up until you get a new one.
Best advice so far. Point the camera in the right direction, level the back, and then don't touch it unless you absolutely have to!Originally Posted by Frank Petronio
It looks like a classic example of yaw to me - the best way to solve it is to start over without movements. Corrections only make it worse, unless you're a mathematical genius who can do both Scheimpflug and Merklinger in your head. I can (although I'm not a mathematician), and when things start going off level like this I reset all movements and start over. It's much easier!
Posting Permissions
Reply With Quote
Bookmarks