Convert normal lenses to soft focus?

[C. D. Keth]

I have an Alphax shutter (came with a Protar VIIA set) with 45mm threads. A 45-52 adapter allows me to place a Nikon close-up filter behind the iris. Like a meniscus, the image is very soft wide open, and sharpens as I close down the iris. Even taping a close-up filter behind any empty shutter would also work--you just have to calculate the f-stops for the filter.

Most of you probably already have everything it takes to make such an improvised soft-focus lens.

Keith

I'll add to that a simple little piece of math that might be helpful. Close up lenses are labeled in diopters, as in a "+1 diopter." The diopter number is 1000/f where f is the focal length so a +1 diopter is a 1 meter lens, a +2 is a 500mm, etc.

[Mark Barendt]

Given the recent history of increasing interest in "name" soft focus lenses I can understand that there would not be much risk involved in buying one. I will have to admit, however, that my interest at this point lies primarily in understanding how these lenses work, i.e. which aberrations are most responsible for the look. After seeing the scene from Casablanca I opened a copy of Russ Young's doctoral theses from St. Andrews University on soft focus lenses and Pictorialism (http://research-repository.st-andrew...ndle/10023/505) to get some historical perspective on the use of soft focus, and the optical explanation of why they work. Russ Young's work must be very good because he had the good sense to quote from one of my research works on Pictorialism!

Thanks for all of the interesting information you and others have provided on this subject.

Sandy

Russ Young's paper is really quite a good read, found it a while back and keep coming back to it for various reasons.

[Andrew Plume]

Hi Sandy

first up, you're much respected in the UK, for the quality of your work, general modesty, knowledge and total lack of b******t, and someone who I immediately relate to along the lines of Merg Ross (who should be considered as being a 'treasure of the LF world')

the last time that we talked online, you had a Shen Hao, I'm assuming that you have moved on from that one..........?

soft focus images haven't from my memory, been part of your regular output but I'd immediately echo an earlier post. maybe from the respected Mark Sawyer, buy a known sf lens, it will hold it's value

best regards

andrew

[sanking]

Hi Andrew,

I certainly appreciate the kind comments. Along with the arthritis age does impart some wisdom in communicating with others about areas of common interest.

I have owned two Shen-Hao 5X7" cameras and liked both of them, but sold them because I found myself still using most of the time the small and compact 5X7" Nagaoka that I purchased back in the early 1980s. I have also owned some other 5X7" cameras over the years but for one reason or another I keep coming back to the Nagaoka as "the camera of my life." You might not be surprised to know that I have been married to the same woman since 1968!

You are absolutely correct in that soft focus has not been part of my personal photographic vision, but I am fascinated by it in the same way that I am fascinated by Pictorialism, though I don't often make images that would be considered pictorial. At least not in the sense of capital P pictorialism. In any event, for some reason I have reached a point in my life when I would like to experiment more with images that are not necessarily tack sharp so I am definitely looking into the possibility of buying a nice soft focus lens. The only issue is that the small lens board and limited bellows draw of my Nagaoka, which to this point has not been an issue in landscape photography, does limit the choice of soft focus lenses.

BTW, just so you will know that I have not abandoned sharp focus stuff I am attaching a revised image I am currently working on. The original is a 12X20" negative made a decade ago, the final version of which is still pending. I am getting close, having printed the attached file as a 24"X38" inkjet with Cone K7 inks, and as a 16"X 24" carbon transfer. My wife had indicated that she liked the image and would like to have a print in her office. I expected she would want the carbon transfer, but she burst my bubble in asking for the inkjet. I guess it is just we photographers who get process! Curious, it is one of those images that does not look sharp at all when printed small, but once you go big the detail just sings.

Best,

Sandy

[Brian C. Miller]

The only issue is that the small lens board and limited bellows draw of my Nagaoka, which to this point has not been an issue in landscape photography, does limit the choice of soft focus lenses.

(Flickr: Johnnyoptic, DIY Soft Focus Lens: Replicating the Rodenstock Imagon)

Ok, that's a problem. I presume that you can fit a Copal 3 on your lens board. The next question is, how close do you want to focus? The best lens for your is probably a 250mm, either Fuji or Rodenstock. Since your maximum draw is 385mm, you could definitely do portrait distances with it, but you wouldn't get close to macro. I presume you have a 240mm lens. Focus range wise, how does that work for you?

[sanking]

(Flickr: Johnnyoptic, DIY Soft Focus Lens: Replicating the Rodenstock Imagon)

Ok, that's a problem. I presume that you can fit a Copal 3 on your lens board. The next question is, how close do you want to focus? The best lens for your is probably a 250mm, either Fuji or Rodenstock. Since your maximum draw is 385mm, you could definitely do portrait distances with it, but you wouldn't get close to macro. I presume you have a 240mm lens. Focus range wise, how does that work for you?

Size of the lens board is 95mm X 105mm. I am pretty sure a Copal #3 would hang on there.

I do use a 240mm lens for 5X7, a f/9 Fujinon-A. Great lens for landscapes and will focus with the Nagaoka to 5-7'. Not very bright indoors, though.

Sandy

[Jim Galli]

Sandy, do you have any petzval's at all in your collection? 6" projection petzval maybe? If so, turn the front element alone around to face the film. That doublet is the basis of most of the soft focus lenses. I have a nice 5" projection petzval I can sell you cheap. The front element alone is about 8 1/2" soft focus.

[Doug Webb]

I have used my 250 Fujinon soft focus lens on my Wista 4x5 and managed to mount the big shutter on a Wista lensboard. Needed a top hat board for portrait distances because of the shorter bellows draw on the Wista. I have a 67mm softar and several Tiffen 52mm soft focus filters that I have not used in a long while. Don't know whether these filter sizes would work for you. If you wanted to borrow one or more of these and would be willing to pay shipping and to return them to me when you are done I could loan them to you for experimentation. Shipping would be probably only a few dollars. The softar has a defect that has shown up in a print, but also has not been a problem at times. There is a learning curve with soft focus filters.
Doug Webb

[russyoung]

Russ Young's paper is really quite a good read, found it a while back and keep coming back to it for various reasons.

I appreciate your comment, Mark. If you'd be so kind, I'd appreciate any criticisms as well sent as a PM. Am in the process of rewriting the dissertation to publish as a book - with the addition of about four more chapters and maybe another 200 illustrations. Give me some guidance, please.

Mark Sawyer's earlier post does a great job of summarizing why filters which destroy resolution are not equivalent to a soft focus lens. Perhaps the key issue is that when soft focus is produced by spherical aberration (perhaps in combination with some chromatic aberration), the image formed has a firm core image overlain by a less sharp image. No filter placed in front of a sharp lens can achieve this effect although the original form of DUTO filter is the closest approximation.

Russ

[Ken Lee]

Is that link disabled or obsolete ? I can't get to the document.