Sharper Imagon Examples

[Frank Petronio]

I'm semi-interested in Imagons, likely because I found a deal on one... how sharp can you make an Imagon while still being wide open? I am not a fan of the extreme softness I see on some of the photos - does anyone have any examples?

I don't mean stuff shot at f/32, I mean wide open or f/8-11 range but with the least severe disc (which one is that by the way?)

I'm hoping it is almost "normal" looking ;-p

Thanks

[BrianShaw]

I'm not intimately familiar with Imagon but selected a Fujinon for the same reasons you enquire about. It was always my impression that it was easier to get sharp soft-focus with Fujinon rather than Imagon. For the Fujinon "wide open" is quite different depending upon which disc is in place. With a red disk wide open is actually rather stopped down, but the effect is a rather sharp soft.

I look forward to reading more knowledgable replies though.

[Bob Salomon]

With the Imagons up to 250mm in Copal shutter 3 disks are supplied, with the 300mm in Copal 2 disks are supplied. In all cases the disk with the smallest center hole will be the sharpest and with all of that disk's outside holes closed the Imagon is very sharp.

The softest and most halation will always be with no disk. The disk with the largest center hole will will be next softest with all outside holes open. With the outside holes closed it will become a litlle sharper with a little less halation. The next disk also gets progressively less soft with progressively less halation depending on if the outside holes are open or closed.

Since the Imagon effect is strongly influenced by lighting ratios and the character of the light the Imagon is normally used at a strong ratio of about 5:1 and with strong spectrals since that is what halos.

So, with the largest disk or wide open an Imaagaon will be at its softest. With the smallest disk with the outside holes closed the Imagon will be at the smallest H number and will be at its sharpest. Exactly the opposite of what you are asking for. A 200 or 250mm in Copal is an H 5.8 lens. The largest disk is H5.8 to 7.7. The 300mm in Copal is a H 6.8 lens and the largest disk is H 7.7 to 9.5.

[Mark Woods]

I own a 200mm & 300mm Imagon. I use them wide open most often and really enjoy the softness. The 200mm is supposed to be used for 6x9, but it covers my 8x10 and give a beautiful image. Using the most open disk considerably increases the sharpness. Bob's analysis is very accurate. Frank, with the widest open disk, the F/Stop is F/6.3 for the 300mm and F/5.7 for the 200mm. They're a single element lens and neither of mine are coated. The example is a scan from an 11x14 print made from an 8x10 neg with the 200mm Imagon. Have fun with it.

[Brian C. Miller]

I'm semi-interested in Imagons, likely because I found a deal on one... how sharp can you make an Imagon while still being wide open?

Frank, you can make a "zone plate" for yourself and experiment with it without buying a thing. The Fuji SF and the Imagon both use zone plates, and you can make one yourself. Just take some black paper, and cut some holes in it. For a f/5.6 lens, the center hole would be at the f/11 size, and punch out holes at the f/8 size. Sandwich it inside the lens, and see what you get.

[SergeiR]

Frank, you can make a "zone plate" for yourself and experiment with it without buying a thing. The Fuji SF and the Imagon both use zone plates, and you can make one yourself. Just take some black paper, and cut some holes in it. For a f/5.6 lens, the center hole would be at the f/11 size, and punch out holes at the f/8 size. Sandwich it inside the lens, and see what you get.

Cant vouch for imagon (although if its similar to 180mm SF on RZ i can) , but Fujinon is soft without disks. Amount of apparent softness is very different for different lighting situations.
And it gets pretty darn sharp once you crossing over into 11 and smaller

[Sevo]

I'm semi-interested in Imagons, likely because I found a deal on one... how sharp can you make an Imagon while still being wide open?

Not at all - that is, the softness is aperture controlled, the lens is sharp by f/11 (the size of the central hole in the aperture disks). Wide open, that is, with no disk attached, it is mushy indeed.

[Ed Bray]

With the Imagons up to 250mm in Copal shutter 3 disks are supplied, with the 300mm in Copal 2 disks are supplied. In all cases the disk with the smallest center hole will be the sharpest and with all of that disk's outside holes closed the Imagon is very sharp.

The softest and most halation will always be with no disk. The disk with the largest center hole will will be next softest with all outside holes open. With the outside holes closed it will become a litlle sharper with a little less halation. The next disk also gets progressively less soft with progressively less halation depending on if the outside holes are open or closed.

Since the Imagon effect is strongly influenced by lighting ratios and the character of the light the Imagon is normally used at a strong ratio of about 5:1 and with strong spectrals since that is what halos.

So, with the largest disk or wide open an Imaagaon will be at its softest. With the smallest disk with the outside holes closed the Imagon will be at the smallest H number and will be at its sharpest. Exactly the opposite of what you are asking for. A 200 or 250mm in Copal is an H 5.8 lens. The largest disk is H5.8 to 7.7. The 300mm in Copal is a H 6.8 lens and the largest disk is H 7.7 to 9.5.


I own a 200mm & 300mm Imagon. I use them wide open most often and really enjoy the softness. The 200mm is supposed to be used for 6x9, but it covers my 8x10 and give a beautiful image. Using the most open disk considerably increases the sharpness. Bob's analysis is very accurate. Frank, with the widest open disk, the F/Stop is F/6.3 for the 300mm and F/5.7 for the 200mm. They're a single element lens and neither of mine are coated. The example is a scan from an 11x14 print made from an 8x10 neg with the 200mm Imagon. Have fun with it.

I have a 200mm Imagon, I have not actually used it yet but it is currently in the Synchro Compur shutter of my 300mm Symmar-S. I understood that the greater softness was produced by using the most open aperture along with the peripheral holes also open, is this not the case? as the statements in red above seem to contradict the one in green.

If I do not use the supplied disks but were to use the diaphragm in the shutter, would this give a sharper result?

[William Whitaker]

...how sharp can you make an Imagon while still being wide open?


"Sharp" and "wide-open" seem to be mutually exclusive terms in the context of the Imagon. What is it you're looking for, Frank? Shallow DOF? Something a Commercial Ektar or a plasmat won't do?

[Bob Salomon]

Brian,

That is not how an Imagon works. That is how you control an Imagon.

The peripheral area of the Imagon casts an image as does the center on the image plane. The peripheral holes on the Imagon disk control how much of those peripheral areas will be used to make the exposure.

Lastly the Fuji places the disk inside their lens. The Imagon has no inside to place the disks in. The disks are positioned in front of the lens.

So your advice to Frank won't work if you want to try to simulate an Imagon.

[Bob Salomon]

I have a 200mm Imagon, I have not actually used it yet but it is currently in the Synchro Compur shutter of my 300mm Symmar-S. I understood that the greater softness was produced by using the most open aperture along with the peripheral holes also open, is this not the case? as the statements in red above seem to contradict the one in green.

If I do not use the supplied disks but were to use the diaphragm in the shutter, would this give a sharper result?

You can use the Imagon without a disk and that will be the softest and have the most halation. The H value with no disk on the 200mm is 5.8.
If you use the disk marked 5.8 to 7.7 with all the outside holes open you will also have an H value of 5.8 but there will be less softness and less halation then there was with no disk.

If you use that disk with all the outside holes closed the H value is 7.7 and the lens will become a bit sharper and have less halation again. If you use the middle disk with all the holes open you will also be at an H value of 7.7 but you again will be a bit sharper and a bit less halation again.

Some of the classic Imagon portrait shooters like Monte Zucker and Tibor Horvath shot with the second disk (7.7 to 9.5) with the outside holes fully open.

You should never use the aperture in the shutter if you want the effect of the Imagon. When you use the aperture in the shutter you block the peripheral rays and lose the classic Imagon look and feel.

[Ed Bray]

Thanks Bob, I will try it out this weekend.

Silly question maybe, but if I half close the holes in the middle disk would that give an intermediate value say for the middle disk circa f8.6?

[jp]

I'm semi-interested in Imagons, likely because I found a deal on one... how sharp can you make an Imagon while still being wide open? I am not a fan of the extreme softness I see on some of the photos - does anyone have any examples?

I don't mean stuff shot at f/32, I mean wide open or f/8-11 range but with the least severe disc (which one is that by the way?)

I'm hoping it is almost "normal" looking ;-p

Thanks

Imagon wide open (with no disc) is very mushy. With discs isnt' wide open even thought he iris is wide open. I dont have examples and you really do need examples. Other portrait soft lenses firm up a great deal by f8 or f11 like the kodak 305 which would look pretty normal at f11.

A fuji (which is a triplet) are also usually good deals. I don't think they are that soft, even wide open without a disc. I have a 250mm version I bought just for the shutter. I don't have much practical experience with it yet, but I'd guess f8-11 would be reasonably normal looking (underwhelming in effect); probably like a generics triplet.

[Mark Sawyer]

You can use the Imagon without a disk and that will be the softest and have the most halation. The H value with no disk on the 200mm is 5.8. If you use the disk marked 5.8 to 7.7 with all the outside holes open you will also have an H value of 5.8 but there will be less softness and less halation then there was with no disk.

Bob, is the H-value equivalent to the F/stop ratio in figuring the exposure? My Imagons are about f/4.8 without a disc, and there's no way a lens can be the same vlue (h-5.8) both with and without the disc.

A couple of old examples, wide open from a 300mm Imagon on 8x10:

http://i55.photobucket.com/albums/g139/Owen21k/J-1.jpg

And from a 360mm Imagon with the holes open (This is as soft as the Imagon gets using the softest disc):

http://i55.photobucket.com/albums/g139/Owen21k/360Imagonwh5.jpg

The Imagon can be used to lovely effect with either a conventional aperture or the discs. Slightly different effects, but I like them both.

[Bob Salomon]

MarK, With the first disk fully open and no disk the lens is H5.8. With the first disk fully closed and the second disk fully open it is 7.7 and with the second disk fully closed and the last disk fully open it is 9.5.

These are H numbers not F stops but generally they correspond to the nearest F stop so: 5.6, 8.0 and almost f11.

[Mark Woods]

Hello Ed,

I think my English wasn't as accurate as it should've been. By "wide open" I mean with no disks. By the "most open disk" means that a disk is used, the one with the most open F/Stop. And, IMHO, it increases the sharpness of the lens more than I like. And, if the Imagon is mounted in a shutter where the iris works, one could use that iris. The effect would be different than the disks, but it could be a look that a person could really like.

Hope this helps.

[Shen45]

I have a 200 Imagon that I have used with either the "tea strainers" or the built in iris of a shutter. The lens is amazingly versatile and produces very different images when used in the two ways mentioned. With an iris at about f8 the result is something like the very best classic lenses with the beautiful mix of well defined sharpness mixed with the intrusion of the [as it appears to me] errors of the outer edges of the lens. The discs and this depends on which one is used produce results unlike any other SF lens I have. Care has to be taken with the out of focus areas when using the discs as IMO the lens can render highlight areas a bit like a bad mirror telephoto of the 70's if you are not careful.

I was intrigued to see the 200 used on a 10x8, that really is something.

[Mark Woods]

Bob, I think your response is to Mark Sawyer, not me. Shen45, I was surprised that the 200mm covered my 8x10. I really like it.

[maurits]

Frank, here's a sequence of test shots I made with an Imagon 250 mm H=5,8 about a year ago.

In all, the aperture of the Compound shutter was left wide open. The first image was made without a disk. Then the three disks were used, first open and then closed.

No disk.

81508

[maurits]

Disk 1 H=5,8 - H=7,7

81509 81510

[maurits]

Disk 2 H=7,7 - H=9,5

81511 81512

[maurits]

Disk 3 H=9,5 - H=11,5

81513 81514

Hope this helps!


Maurits

[Adamphotoman]

When I found my 200mm Imagon 4 years ago it came boxed with 3 disks and a ND filter, mounted in a Sinar engraved barrel attached to Sinar board. I went looking for info and found some. I will need to find it and I will post. Since I have converted to the scan back my new format is 72X96. The lens is well suited to this format. I have still the older P 8X10 kit and viewing the GG the lens does light up the larger format.

Here is an excerpt from an email that I got from my inquiry. Keep in mind that the light ratio is maybe the most important factor. The above samples from Maurits are well done but they only tell one side of the story and that is images shot in soft overcast light.


The 'H' is coming from the German 'HELLIGHEIT', meaning 'clearness — brightness' and, in this case, the amount of light that is available to expose the film when the disc is mounted and opened ore closed (and all the steps between that). These discs are no real apertures, the centre hole, which is not changing when turning the disc's ring, is perhaps somewhat like an aperture, but the little holes around it are regulating the amount of optic (spheric-) aberrations and also the transmission of light. One might not forget that a so called 'soft' image is more brighter than a rather 'normal-to-hard' image. A soft image 'contains' more light and, by this, is exposing the film whit that typical amount of light.
The Imagon whit out a disc is far more softer, thus more brighter (hell), than an other lens of the same focal length and diameter (opening).
So, each disc has a fixed pseudo aperture and a very own amount of light transmission via the perepheric holes. This is why each disc, and the lens not having an aperture only a diameter and typical (aberrated) light coming through (!), is considered to have a HELLIGHET (brightness) and not a F number.
You will see that, when the disc with the highest H value is mounted and closed, there is far less light 'coming through' than compared to a normal working lens with a normal aperture system and closed to the same amount, if you understand what I mean.
Helligheit has to do with the (artistic?) effect of the amount of light, and aperture with the mathematic amount of light (energy), reaching the film.

I hope, dear Samuel, that my pidgin English was clear (bright) enough, so that you could understand all what was to do about 'H'.

[Adamphotoman]

Information on Seth Broder's site Camera Eccentric
http://www.cameraeccentric.com/html/info/imagon_2.html

[Adamphotoman]

81589815908159181592Here are 2 images shot with the smallest H-9.5 / H-11.5 disk
9.5 is with the (tea strainer) holes fully opened which introduces aberrations.
11.5 is with the (tea strainer) holes fully closed, and this is as sharp as it gets with the supplied hardware unless you use a smaller opening with the shuttered aperture.

Shot 100% on a Betterlight Super 6 K. Since the Betterlight does absolutely no sharpening. I used USM values 150 / .07 pixel 0 threshold.
Then I cropped.
If anyone wants a full sized image I can send one via WE Transfer.

[thomasfallon]

Some original product literature in the Rodenstock section of this pdf:

www.bhphotovideo.com/.../Product.../Section04LgFormatLenses.pdf



Sorry about that. The link is not working. Just Google Imagon bhphoto and you will see a pdf.