If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Front tilt loses middle
I should know this procedure, but my results say otherwise. When I
front tilt for maximum depth of field then check that my forground and background are sharp, should I then focus the middle ground for final focus? I am seeking complete all over focus. I have been losing middle ground sharpness in situations where even a tilt would probably not have been necessary, i.e. shooting a full ocean view from a high cliff. I was amazed to find that detail in the middle of these images was soft. My apertures are always either f/22 or f/32. There appears to be a critical step here that I am overlooking. Thanks for your help. |
#2
|
|||
|
|||
Front tilt loses middle
wrote in message ps.com... I should know this procedure, but my results say otherwise. When I front tilt for maximum depth of field then check that my forground and background are sharp, should I then focus the middle ground for final focus? I am seeking complete all over focus. I have been losing middle ground sharpness in situations where even a tilt would probably not have been necessary, i.e. shooting a full ocean view from a high cliff. I was amazed to find that detail in the middle of these images was soft. My apertures are always either f/22 or f/32. There appears to be a critical step here that I am overlooking. Thanks for your help. When you tilt either the back or the lens of a camera you are tilting the plane of focus. Everything in that plane should be in focus but stuff outside of it may not be. Imagine a flat plane in front tilted the opposite direction of the back. If the subject area you want focused lies in this plane all of it should be in focus simultaneously. Now, it may be that you are focusing on something that does not lie in a tilted plane or that the lens has too much curvature of field. Both can be cured to some extent by stopping down. The procedure depends somewhat on how the camera is made. Some cameras tilt from the center and some from the base of the back. Those that tilt from the center will tend to maintain focus at the center of the image as the back is tilted, base tilt cameras will require re-focusing for the center. It may take some juggling of tilt and focus to get it right. Again, if the objects you want to get into focus do not lie on the same plane the tilting trick will not work. -- --- Richard Knoppow Los Angeles, CA, USA -- Posted via a free Usenet account from http://www.teranews.com |
#3
|
|||
|
|||
Front tilt loses middle
|
#4
|
|||
|
|||
Front tilt loses middle
Depends on whether you have on-axis tilt or if you're using base tilt. I'd
bet a nickel that you're also using too much tilt and you're basically throwing the middle out of focus by doing so. The most common mistake I see students doing when I help teach workshops is using too much tilt. For some reason some seem to think that the lens board has to be tilted at the same angle that they're trying to aim the lens. You typically only need a few degrees of on-axis tilt to keep the field of view in focus. If you're using base tilt, you'll want to re-check your focus every time you use tilt, front or rear. Another common mistake is people trying to get everything in focus with the lens wide open, it doesn't work that way, you really need to get under the focusing cloth with the lens stopped down at your shooting aperture and check your focus points with a loupe, it's the only way to know for sure that you've got what you want in focus. John Emmons wrote in message ps.com... I should know this procedure, but my results say otherwise. When I front tilt for maximum depth of field then check that my forground and background are sharp, should I then focus the middle ground for final focus? I am seeking complete all over focus. I have been losing middle ground sharpness in situations where even a tilt would probably not have been necessary, i.e. shooting a full ocean view from a high cliff. I was amazed to find that detail in the middle of these images was soft. My apertures are always either f/22 or f/32. There appears to be a critical step here that I am overlooking. Thanks for your help. |
#5
|
|||
|
|||
Front tilt loses middle
Some good advice. Thanks. I think I have what you call axis tilt on a
5x7 Linhof and a converted Crown Graphic 4x5, if this means the center of the board tilts. I do use a tiny amount, but in the case of the vast ocean taken from a high vantage point I must say I'm mystified. A little was used to make sharp tiny beach rocks to horizon, yet on the larger rocks sticking up in the middle of the scene at f/22 with a 180 lens, its soft. I'm going to revert back to middle ground focusing after my tilting, then see if the aperture brings it all together. John Emmons wrote: Depends on whether you have on-axis tilt or if you're using base tilt. I'd bet a nickel that you're also using too much tilt and you're basically throwing the middle out of focus by doing so. The most common mistake I see students doing when I help teach workshops is using too much tilt. For some reason some seem to think that the lens board has to be tilted at the same angle that they're trying to aim the lens. You typically only need a few degrees of on-axis tilt to keep the field of view in focus. If you're using base tilt, you'll want to re-check your focus every time you use tilt, front or rear. Another common mistake is people trying to get everything in focus with the lens wide open, it doesn't work that way, you really need to get under the focusing cloth with the lens stopped down at your shooting aperture and check your focus points with a loupe, it's the only way to know for sure that you've got what you want in focus. John Emmons wrote in message ps.com... I should know this procedure, but my results say otherwise. When I front tilt for maximum depth of field then check that my forground and background are sharp, should I then focus the middle ground for final focus? I am seeking complete all over focus. I have been losing middle ground sharpness in situations where even a tilt would probably not have been necessary, i.e. shooting a full ocean view from a high cliff. I was amazed to find that detail in the middle of these images was soft. My apertures are always either f/22 or f/32. There appears to be a critical step here that I am overlooking. Thanks for your help. |
#6
|
|||
|
|||
Front tilt loses middle
wrote in Some good advice. Thanks. I think I have what you call axis tilt on a 5x7 Linhof and a converted Crown Graphic 4x5, if this means the center of the board tilts. I do use a tiny amount, but in the case of the vast ocean taken from a high vantage point I must say I'm mystified. A little was used to make sharp tiny beach rocks to horizon, yet on the larger rocks sticking up in the middle of the scene at f/22 with a 180 lens, its soft. I'm going to revert back to middle ground focusing after my tilting, then see if the aperture brings it all together. It sounds like you have the situation that Richard referred to: the big rocks sticking up in the middle of the scene may be outside the plane of focus you created with your tilt. You can prove that to yourself if the bases of the rocks (say if there is beach around the bases of the large rocks in the middle) are sharp. If that's the case, and is the best you can do, then close down to at least f/32. That may sharpen the middle rocks some. Again, if you are properly making your tilt, a beach and ocean scene should have no trouble being sharp from right up close to the horizon because your scene is pretty much a flat plane. Anything sticking up out of that plane is not going to be in focus, and you're limited to correcting that with your lens' diaphragm. |
#7
|
|||
|
|||
Front tilt loses middle
The plane of focus, the plane of the film and the plane of the lens board
will all intersect at the same imaginary point unless of course they're all parallel to one another. Stopping down will increase the depth of field of the plane of focus in both directions away from it. "John Emmons" The most common mistake I see students doing when I help teach workshops is using too much tilt. For some reason some seem to think that the lens board has to be tilted at the same angle that they're trying to aim the lens. |
#8
|
|||
|
|||
Front tilt loses middle
A famous example of what the OP is describing can be seen in Adams'
photograph of the Alabama Hills. The middle ground is not as sharp as the foreground or the distant mountain tops. John Emmons "Howard Lester" wrote in message ... wrote in Some good advice. Thanks. I think I have what you call axis tilt on a 5x7 Linhof and a converted Crown Graphic 4x5, if this means the center of the board tilts. I do use a tiny amount, but in the case of the vast ocean taken from a high vantage point I must say I'm mystified. A little was used to make sharp tiny beach rocks to horizon, yet on the larger rocks sticking up in the middle of the scene at f/22 with a 180 lens, its soft. I'm going to revert back to middle ground focusing after my tilting, then see if the aperture brings it all together. It sounds like you have the situation that Richard referred to: the big rocks sticking up in the middle of the scene may be outside the plane of focus you created with your tilt. You can prove that to yourself if the bases of the rocks (say if there is beach around the bases of the large rocks in the middle) are sharp. If that's the case, and is the best you can do, then close down to at least f/32. That may sharpen the middle rocks some. Again, if you are properly making your tilt, a beach and ocean scene should have no trouble being sharp from right up close to the horizon because your scene is pretty much a flat plane. Anything sticking up out of that plane is not going to be in focus, and you're limited to correcting that with your lens' diaphragm. |
#9
|
|||
|
|||
Front tilt loses middle
|
#10
|
|||
|
|||
Front tilt loses middle
"Leonard Evens" wrote In your example it was not true that everything you wanted to be in focus was in a single plane. So necessarily you had to rely on stopping down to get everything in adequate focus. You may have chosen your exact plane of focus to be close to the plane of the ocean. That way it might have required you to stop down quite far to get the rocks in the middle ground in adequate focus. It might have been better to adjust the tilt and separation of the standards so that the plane of focus passed halfy up to the midground rocks. Then you might have been able to get both the ocean and the top of the midground formation with a more modest aperture. Great explanation, Leonard, even if I don't understand half of it. ;-) But you bring up a good, um, point... choosing the points of nearest and farthest requires some thought for the final composition. Normally I'd do something boneheaded like choose the very near foreground (good choice for sharp impact) and the ocean's distant horizon, leaving me with the puzzle the OP has presented. However, since in this case the far point is an ocean horizon, which has some "built-in fuzziness," your solution (if I understand it correctly) is probably better: use the middle rocks as the far point and let the background fall where it will depending on the chosen aperture. In a photograph, the eye is much more forgiving of distant softness than either middle, or near-ground softness. View cameras allow for solutions to problems that "fixed" cameras cannot possibly solve. However, it does take some thinking.... ;-) It ain't snapshooting. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
they are loving among old, in front of worthwhile, in front of kind tyrants | Jamie | Digital Photography | 0 | May 5th 06 03:55 AM |
they are loving among old, in front of worthwhile, in front of kind tyrants | Jamie | 35mm Photo Equipment | 0 | May 5th 06 03:55 AM |
ANNI LOSES AGAIN !!! | Annika1980 | 35mm Photo Equipment | 1 | August 9th 04 06:39 AM |
ANNI LOSES AGAIN !!! | Annika1980 | Digital Photography | 15 | August 4th 04 09:39 PM |
ANNI LOSES AGAIN !!! | Annika1980 | 35mm Photo Equipment | 8 | August 4th 04 03:42 AM |