Thanks for that. I just thought it was strange the way the portion in the middle came up slightly out of focus. I guess that has to dow with the movement I made? But it's hard for me to visualize.Originally Posted by Michael R
Thanks for that. I just thought it was strange the way the portion in the middle came up slightly out of focus. I guess that has to dow with the movement I made? But it's hard for me to visualize.
Flickr Home Page: https://www.flickr.com/photos/alanklein2000/albums
The diagram is meant to show how objects in those areas could potentially be out of focus even though objects farther away or closer are ok. Here is the same diagram with some objects/areas of your picture very roughly superimposed. Imagine we are looking at the whole setup from the side (to the right of the fence).
The yellow shaded area is outside the depth of field. You can see therefore that distant parts of the fence would be increasingly blurry. You can also see how the lowest parts of the building facade and the ground in front of it would also be out of focus since they are in the yellow zone (outside depth of field).
Disclaimer: Please note this is for illustrative purposes only, to show how this sort of artifact might be created. It's an exaggerated picture. There are also variables - how much tilt, points of focus chosen in determining tilt, and of course aperture (which determines how wide or narrow the wedge-shaped depth of field is). And who knows - as Drew noted film flatness is occasionally a wild card.
As an aside, referring back to Adam's second colour picture (bush), this diagram shows why in his case the railing goes from sharp (at the top) to blurry (at the bottom).
Different movement choices, chosen points of focus, and aperture can usually solve this type of problem. It takes some practice to get used to it, so don't be discouraged. I understand the initial frustration though. Theoretically this is all discernable on the groundglass (WYSIWYG) but it isn't always easy to see well. This is why in the end most people end up stopping down to at least f/22, usually more, plus "Kentucky windage", even if they think they've nailed it.
Technically there are formulas for figuring it all out, but good luck with that unless you want to send your surveyor out first.
Hope this helps.
Sinar P and F cameras, and later certain other brands of monorails, had certain built-in methods of approximating depth of field in relation to tilts and swings, along with asymmetrical controls. I learned that method and understand why it is speeds up the efficiency of tabletop studio photography of catalog products, food photography, etc, where planes are artificially controlled. Then I promptly ignored it, and now even prefer the Norma version of Sinar prior to any of those innovations because they have little impact on the real world nature of my own work.
Yes my Sinar A1 (a cheaper version of the F1) had that system. It worked pretty well and was very easy to use.
There’s the Linhof calculator and some others.
Most people seem to prefer eyeballing it using one of the old fashioned methods. And there aren’t many, if any field cameras with built in mechanisms like the Sinar anyway.
Beautiful day yesterday, and I was out on a long open ridge with the Norma, carrying both b&w and color film, relatively simple near-to-far subject matter. Pretty much just front tilt control, no brainer. But still, undulating planes were involved. So, after basic foreground to skyline accommodation using the tilt, and checking the loupe for that, I then picked out whatever detail or set of details within that particular scene I wanted in exact focus, just in case the shot came out worthy of being enlarged to big scale. That was all done wide-open. After the lens is stopped down, everything will be in acute focus, although I did have to make a bit of a compromise, f/22 vs f/32, for sake of a bit more shutter speed due to the wind. This kind of activity becomes intuitive with practice. I simply couldn't waste a lot of mental energy over it. I had other priorities. The light and cloud shapes were constantly changing, the wind gusts were unpredictable, and hikers and trail bikers intermittently appeared in the scene, so I had at most a 1 or 2 second opportunity in each case to get it right.
In such cases, all the technical details themselves need to be second nature. Will every shot come out ideal? Of course not. Not even Babe Ruth hit a home run every time he was up to bat. But I am confident something quite worthy of printing did transpire yesterday. But even if I had never pulled the camera out of the pack, it was a joy just to take it all in. Next week that same area is forecast to be too hot for me, and the color patterns will significantly change due to things drying out, about a month early this year due to moderate drought.
Luckily my pictures are really all local “urban landscape” type so I’m nearly always limited to rise/fall/shift. Due to the type of pictures I take I never got very good at tilt/swing. I know the theory and the math but it isn’t worth a whole lot in the field. As you point out, you really need to get comfortable by doing it. Repetition etc. and it becomes more fluid. Most importantly, as you gain experience you are better able to judge/evaluate what’s in front of you and know what you will get from some amount of tilt etc. with some confidence. I never got there. But hopefully some basic visualizations will help Alan.
The nice thing about the Sinar monorail system is that you've got all the options; and the same gear works well for architectural use, studio usage, and typical landscape applications. And it's certainly portable enough for day use. But add two weeks worth of food and full mountain gear to that same pack, plus the 70+ age factor, and one should realistically forgive me for owning a couple of less versatile but significantly lighter wooden folders too.
I have a monorail and a nice little folder, but I should never have replaced the Sinar. It was a dumb decision and always regretted it.
So what's this thread about now
Anything in life worth having is worth sharing.
It's always been the same thread. If you don't think so, just get any old Sinar handbook and see how they describe the original topic - one of the best learner resources you can have, whether or not you use their own cameras. Simplifying this very depth of field topic was behind their key patents.
Posting Permissions
Reply With Quote
Bookmarks