8X10 depth of field. How bad is it?

[robert_4927]

Michael, I speak with William often and will be shooting with him in the near future. So I'll quote him. " I like to keep it simple; one camera, one lens, and one fstop ( I kind of like f128). I don't want to think out there, only feel." Now I'm sure some of his portriat work may have been shot at f16 but I'll ask him how many of his landscapes were shot at f16. I think I already know the answer but I'll ask anyway. Please explain to me how optical degradation changes by just removing a lens from an 8x20 camera to an 8x10. The lens' image circle would be the same. The lens doesn't know what camera it is on. I have shot with my 16 1/2" dagor on both my 8x10 and 8x20 using the same f64 and I don't see this optical degradation you are talking about. If anything there is more bokeh ( for lack of a better word) on the 8x20 images out near the edges than on the 8x10 because I'm using more of the image circle. I'm talking about lens resolution and depth of field here. I hardly consider that comparing apples to oranges. Bill I agree max resolution is not always desired . I shoot a lot of portraits with an old Verito. So at times I'm trying to achieve soft focus. But Rory asked how to achieve that near and far composition and no one has explained to him yet how to achieve this at f16. I'm not trying to be the devils advocate here . I think it is interesting and fascinating the differences in how many of us work. My methods are not ground in stone so I'm willing to try new ways. My comments are based on how I work and what works for me. In no way are they the only way. Such is the beauty of "artistic expression"

[Ken Lee]

All this talk of bokeh and depth of field has prompted me to go out and make some non-f/64 images this morning. We'll see how they turn out.

[Michael Kadillak]

Robert:

Page 147 of the 7th edition of Stroebel's View Camera Technique on the subject of "Circle of Confusion".

Cheers!

[bglick]

Robert...

> Please explain to me how optical degradation changes by just removing a lens from an 8x20 camera to an 8x10. The lens' image circle would be the same. The lens doesn't know what camera it is on.

Although you asked Mike this, I will offer my opinion.... of course you are right above.... however, Mike is emphazing not mixing apples and oranges.... meaning, if you switch from a larger format to a smaller format, and have the same composure, then obviously have a shorter fl lens. Other than the obvious, which is the outer parts of any image circle are always being less sharp then the sweet cetner area, the results would be similar, but the composition different, specially in the case you described whereas not only did the format change but so did the aspect ratio.

I understand you are not trying to be confrontational, and these forums are for airing out opinions, questions and styles, which is what we are doing. As for Rory's question, I felt it was answered by previous posters..... but to express my opinion on his main question...

> I like to take pictures usually with a foreground object (rock or shrub) and the horizon etc. off in the distance - all in focus.

Well, this is similar to wanting a super high performance car that gets 50 miles per gallon of gas! Some basic rules that are fixed....

1. Double format size = double fl. Longer fl can never add sharpness to an image (assuming lenses of equal optical performance) Longer fl lenses are much more vulnerable to camera shake and are inheriently less sharp (as a general rule). But you gain 2x the film size, assuming that extra gain in sharpness is not compromised by........

2. Double fl = double the f stop for same DOF = double the diffraction losses. Or better said, if in the zone which most LF lenses are used, you loose half the resolution in the process of holding onto the same DOF. In reality, this number is actually much worse, as it's not just the diffraction limited losses, its the application of 1/R to the lower resolving diffraction lens, not good if sharpness is your goal.

3. Double the f stop = 2 stop loss of shutterspeed. This is a no brainer... longer exposure times, more potential for subject blur, and in low light, possible film reciprocity issues.

So in general, if gaining a lot of DOF is your goal, going up in format size is not always advantageous if sharpness is your priority. Now, there is only one caveat, and that is, if the lens can be tilted. However, this only applies, as Jim Galvin explained in a previous thread, when the subject is a plane itself, such as a lake, flat grass, a flat mountain, etc. If you never saw the cone of focus for a tilted lens, be sure to view this picture on Merklingers site as it clearly shows the limitations and best applications for lens tilt. But keep in mind, the longer the fl lens, the more front tilt is required, which means the larger image circle which is required..... to the point where not many lenses have image circles big enough to chase the image crawling up the ground glass. So there is a "window" of potential gain in a short range of fl's, assuming you have the right lenses and the subject's geometric profile is cooperative.

If it was me, and I desired to record extreme near / far scenes, and wanted to shoot LF.... I would only shoot 6x9 on a view camera, or possibly 4x5, based on just how extreme the DOF is. This assumes, as your post stated, that sharpness is your most important criteria. With 4x5 and 6x9 you will have extreme DOF (vs. 810) and extreme tilt capabilities vs. 8x10. By violating these basic principles, sometimes your result is, just lugging heavier gear with no benefits, vs. carrying more types of gear of a smaller format, such as more lenses, film types, film holders, etc etc.

What many of us learn through the years, that bigger is not always better, this is a classic example of such. However, if you pursue this quest, then try tilting the scales in your favor and stick with very short fl lenses on the 8x10, such as the 150mm you mention, dead still subjects, (other than the times you want dreamy waterfalls), bright daylight, cooperative subject geometry, non-extreme near/far, and accurate focus technique. If you adhere to these principles and learn what types of scenes are NOT acceptable, you will have adapted a syle that works around your gear and your desired end result. Many people do this, as they only carry one camera.

As for the actual sharpness recorded.....before you possibly make the mistake like many of us, who get burried in math, only later to find out most of the DOF math is useless.... simply take your lenses and your formats and shoot some test shots of the same type scenes, with all things being equal and comapre the same size final prints...if you see no benefit at the size you desire to print out, then it's simply a "weight lifting" program you are adding to your photography :-) On the other hand, if you see huge gains in the final print, then you will feel justified lugging all this heavy stuff around. Much of this depends on how big you want the final prints to be. I don't know if money is an issue, but if it is, lots of issues with 810, cost is more than double for film and processing, and lots more for scanning. bracketing?

Which brings up, one other possible benefit for 8x10. If you plan to scan, and only use lower end flat beds, such as Epson 4990, then in my opinion, you will surely gain from the larger format, as the more magnified a subject, the easier it is to grab the detail from a scanner, specially the low end scanners.....it essential raises the scannner efficiency. So this may be something you want to consider also. And of course, how significant the money issue is, vs. how many exposures do you make a year. I hope this addresses your question better.... We applaud your courage!

[robert_4927]

Bill , Maybe I wasn't clear on how I work. I shoot 8x10, 8x20 and 14x17. I haven't used an enlarger in probably 5 yr. now so all my work is contact prints. I mainly print in pt/pd. So dealing with long exposures and film reciprocity is not an issue, I deal with it all the time. I don't get buried in the math because I use only a couple of lenses that I have used for years and know exactly how they react to almost any situation. My lenses are older optics because they seem to achieve the vision I want. These are a 14" blue dot Trigor, a 16 1/2" Dagor, a 30" red dot Artar and at times a 14 1/2" Verito in the studio. I find that the worlds sharpest lenses don't meet my requirements or my vision and these older optics seem to have a quality that I have not yet found in the newer optics. I have never claimed to be an optics expert I just know what works best for me. I don't know the first thing about photoshop or high end scanners because I don't need either . I love working with in camera negatives and printing in a hand coated platinum palladium medium. I have spent many years perfecting my process and thousands of hours and thousands of dollars but it is what best allows me to express myself and it is what I find the most gratifying. I haven't bracketed since I put the 35mm and the old Rolleiflex on the shelf. I probably shoot less negatives now than I ever have. I spend hours and at times days on one composition and my successful images seem to be more consistent in the past few years than they have ever been. I'll borrow a phrase from my friend William "I want to feel when I work , not think" So any technical knowledge about lens resolution or light diffraction never comes to mind. Sure I have read Leslie Stroebel's book front to back probably a couple of times. It is very informative and I learned alot from Leslie's text. But I know my equipment well enough and how to use it to achieve my vision that Stoebel's book is now a better paper weight than anything. I spend my time composing more than anything and the rest printing in what many think is a very difficult medium. To avoid starting a digital vs. analog debate let me just say this. If I need to use photoshop to repair or improve my in-camera image I feel, and it's only my opinion, that I have failed as a photographic artist. Now in no way would I recommend my methods to anyone. Photoshop is great for many people. It allows almost anyone with good computer skills the ability to produce very nice images and that is great for photography in general. It is just not gratifiying to me as an artist or a photographer. I love the challenge of producing excellent in-camera negatives without the recourse of knowing that if they are not perfect shoot it anyway and I can fix it in photoshop. I spent a couple of years with the one camera one lens and it did teach me a lot and I found during this time when you learn your camera and your lens there are not many scenes that are not acceptable. You can find a composition in just about any situation and format has nothing to do with it. I have been fortunate to have a master printer and a contributing author to Dick Arentz's book on pt/pd printing as a mentor over the past few years . My printing skills over the years has improved to the point where he has asked me to assist him in the printing of his new series. This may give you a little better understanding of how I work. Like I said, It's not for everyone

[robert_4927]

Bill, I think where we may be misunderstanding each other is what is accepatable to the eye. Take Adam's image of Mt. Williamson. Technically you are right on about resolution. But Rory asked how to achieve the near and far composition. Adams print for one is a contact print so there is no enlarging factor to consider when printing. Now of course if you look close enough you'll see that the far is no where near as sharp as the near. But is is more than sharp enough to be acceptable to the eye. He could not have achieved this at f16 and that is the point I was trying to make. In response to Mike's comment and reference to the Stroebel Bible. Of course the aspect ration changes when you change formats but that doesn't degrade the optics in the least. I love this forum just for the fact that it does refresh a lot of what I never use or even think about when I'm actually being creative and producing images.

[bglick]

Robert

> Bill , Maybe I wasn't clear on how I work.

My comments were only generalized, nothing relating your style.....

> I find that the worlds sharpest lenses don't meet my requirements or my vision and these older optics seem to have a quality that I have not yet found in the newer optics.

You have reached LF Nirvana! Congrats!

> I'll borrow a phrase from my friend William "I want to feel when I work , not think"

Although these "catch phrases" sure sound eloquent, however, there rarely, if ever, can be a disadvantage of having solid knowledge of the equipment you are working with. The process of shooting LF requires lots of thinking, unless your firing a simple shot at infinity. Lack of knowledge whether optics, gear usage, film characteristics, exposure methods, etc. is the easiest way to destroy the vision one desires to record. Having an idea of what you want is only part of the equation, knowing how to accomplish such comes from knowledge and experience, not from "feeling it". I only mention this as many newbies read these posts and I hate to see people be mislead by these types of statements.

> So any technical knowledge about lens resolution or light diffraction never comes to mind.

Without all these basic fundamental principles of photography, I would never have the ability to accomplish my desired goals.... the results would never happen from "feeling the camera" ... in your case, you have been using the same gear for so long, you have seen practically all the results that are possible with many different scenarios, so inheriently, you know what to do, and what not to do. For most others, who use lots of different gear through the years, different film, etc., this is not always possible. But I appluad your system that you perfected and enjoy.

> If I need to use photoshop to repair or improve my in-camera image I feel, and it's only my opinion, that I have failed as a photographic artist. Now in no way would I recommend my methods to anyone.

i feel this digital vs. darkroom issue seems to go from one huge extreme to another. Would you say you failed as an artist if a tiny bit of lens flare hit the film, which occured from the time you looked through the gg, till the time you made the exposure? I wouldn't call that failing. What if the film had a scratch from the manufacturer, and you recorded a fabulous image on it, but it will ruin a contact print, is this the artist failing? I could go on, but its sensless.... yes there is digital extremist, but there is also digital purist that perfer to make an image match the scene they saw, vs. the method the film/darkroom decided to record and print it. So in my view, quite often, the pure darkroom person is NOT the purist, as he presents images differently than the scene appeared. In this case, which artist is failing? Get my drift? It seems darkroom purist tend to think all digital photographers create totaly fake scenes, as the software surely has this power, but it does not have to be used like this.... a hammer can be used as a weapon, or it can put a nail in the wall - to hang art work, it's all according to how you use it.



> This may give you a little better understanding of how I work. Like I said, It's not for everyone

Again, I applaud your accomplishments and someday would love to see some of your work, and that is NOT being saracastic..... there is not many people making 20x24 contact prints in this day of age and I have only seen a few in my time.



> Adams print for one is a contact print so there is no enlarging factor to consider when printing. Now of course if you look close enough you'll see that the far is no where near as sharp as the near. But is is more than sharp enough to be acceptable to the eye.

All this is a mute point, as its impossible to draw these conclusions from lookin at a screen shot of a LF image.... more importantly, the answer usually lies in what the final print size is, and what the viewing distance will be....only then, can one see if near/far sharpness met the desired objective. hence why I suggested or Rory to test with his own gear and own printing methods at the desired size prints he plans to make.

> He could not have achieved this at f16 and that is the point I was trying to make.

And i never disputed this.... I clearly explained this in my previous post. With extreme DOF, if you desire high min standards for near and far sharpness, you compromise the rest of the image by stopping down and allowing diffraction to become the limiting factor throughout the entire composition. Nothing wrong with that, just mentioning the facts, simple as that.... or go to a smaller format!

[robert_4927]

Bill , To avoid being misunderstood by what I mean by" feeling it" allow me to explain. After twenty years behind the same camera and the same lens the basic fundamentals you are refering to become second nature. Things like lighting direction and the need to shade the lens to avoid flare are noticed before the camera ever gets to the tripod. No way am I suggesting that you need no knowledge to work in LF or ULF. By "feeling it" has nothing to do with "feeling the camera". By feeling it I'm refering to the feeling the composition. Like I said previously I know my lenses and my camera well enough and how they perform in about every situation. Do I sit there and think about diffraction-limited resolution when I'm composing or lines/mm at such and such a viewing distance? Of course not! After a few thousand negatives with the same camera, same lens, and same film I pretty much know how and what I'm composing and how to transfer that to the film. The fundamentals are second nature. I "feel" the composition not the camera.

[robert_4927]

Bill, As far as that scratch on that negative goes . Some of us still know how to use a spotting brush and water color pigments and soft lead pencils with amazing success. Like I said , photoshop is great it is just not for me. Keep up the great work and please continue to be such a great source of information for the younger photographers to which you refered. I wish I would have had a forum like this when I first started in photography. It would have helped with the learning curve tremendously. good light

[robert_4927]

I am currently working on a web site. I have finally somewhat conformed to modern day technology and a gallery of my work will be posted soon (I hope). I may have to call in some help on this one. I may have to break down and buy a cheap scanner to be able to change the images on the site from time to time. So I've got as far as purchasing a domain and that's at least a start for me. I look forward to sharing my work with others in the near future.