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e. a. smith
17-Mar-2007, 09:12
I'm trying to get into 4x5 on the cheap ...I've done hours of research ... have learned a little ... but am unclear about a couple of things ...

I've read "multiply your favourite 35mm lens by 3 and that's the focal length you need for 4x5"

I use a 35mm as my "normal" lens ... so that seems to indicate a 105mm. But then this issue of coverage and movement comes up ...

I was given a 100 3.5 Zeiss Tessar ... I see an e-bay auction that describes this as "rare" ... asking price $1300 US ... I assume this is a great lens.

I've been told that this lens is useless for 4x5 ... no movements ... unsharp corners

I want to do outdoor stuff ... probably want some movement

I was planning on ditching this lens cheap ... last night I held the lens up to a too-large lensboard ... it seemed to fill the screen ...

Should I just invest in a 0 board and use this as my WA ... if I do would a recessed board improve coverage and if so what mm board ... and any online source for retaining rings?

Or should I sell it ... is it really $1300 ?

I appreciate any feed back

E. A. Smith
Chaffeys Lock Ontario
Canada

Nick_3536
17-Mar-2007, 09:36
Tessars tend to cover something like 50 degrees. Some less I think a few up to 55 degrees. Pulling out the calculator 55degrees equals 110mm of coverage.

Lighting the ground glass is very different then coverage. Some lenses will light a much bigger circle. The problems is the corners will at best be fuzzy.

The Fuji 105mm SW F/8 will give you plenty of coverage for up to 5x7. Used it can be fairly cheap.

Ash
17-Mar-2007, 09:42
Photo-Arsenal have auction prices at least triple what the item is worth.

Richard Kelham
17-Mar-2007, 10:34
In 35mm terms a 35mm lens is a wide angle. A Tessar is not a wide angle ergo what you have could be useful if you decide to get a roll film back, but otherwise I'd recommend selling it. Could fetch 50 quid if in a reasonable shutter.

If you want that wide angle look then you will have to fork out for a proper wide angle lens such as the 110mm Super Symmar XL or whatever (there are slightly cheaper alternatives!). More sensibly – as you are just starting out – something like a 135mm Xenar would give you a bit of room to manoeuvre, and leave you enough money to eat etc.


Richard

Kirk Fry
17-Mar-2007, 11:34
Since you are new to this game look for an old 135mm Symmar (silver rim) which will be convertable to 240 ish mm also, or a 120mm old Angulon (not super). Then go shoot pictures. After you take 50-100 pictures you will know what to get next. Just because you like a medium wide angle in 35 mm does not mean you will like it in 4X5 as the aspect ratios are different. You need play with the format first. 135mm Xenars were designed for press cameras with very little movement. Straight on they are fine, but no movement. Ignore the 110mm Super Symmar XL, cheap it is not. I suggest you do some reading. Steve Simmons book is good start. K

Ron Marshall
17-Mar-2007, 12:42
Have a look at the websites of both KEH Camera Brokers and Midwest Photo Exchange. Then pick a cheap lens in the range of 120 to 135mm. Buy used then you can trade for another focal length if you want, once you are used to LF. The links below are to KEH and Midwest, and to the lens chart on the front page of this site.

http://www.keh.com/OnLineStore/CategoryTableOfContents.aspx?Mode=&item=0&ActivateTOC2=true&ID=58&BC=LF&BCC=7

http://www.mpex.com/InventoryList.aspx?DID=30&CID=402&FS=Large%20Format&SS=4X5%20/%206X9%20LENSES

http://www.largeformatphotography.info/lenses/LF4x5in.html

David Karp
17-Mar-2007, 13:07
Consider a 125mm f/5.6 Fujinon W (either the older single coated or the newer NW with EBC multicoating). A 105mm f/5.6 Fujinon NW will just cover 4x5. Larger more expensive lenses, like a 120mm f/8 Nikkor, 120mm f/8 Schneider Super Angulon, 125mm f/8 Fujinon, 115mm f/6.8 Rodenstock Grandagon-N, or 105mm f/8 Fujinon SW or SWD, will give you more movements and a darker image on the groundglass. I don't know what kind of camera you have so I don't know if it offers enough movements to take advantage of the larger more expensive lenses. Similarly, I don't know what sort of things you want to photograph.

I second the recommendation of Midwest Photo Exchange (www.mpex.com). Call there and ask for Jim.

e. a. smith
17-Mar-2007, 13:25
Thanks for all the suggestions ... but one thing confuses me ...

If a 150mm is "normal" ... (50mm on 35 cameras) ... why is a 100mm not considered wide angle... its 30 percent shorter than the 150 ...

Why are lenses of the same focal length often given different designations ... some 210s described as tele and others are not ...

What makes a 105 Nikor a wide angle but a 100 Tessar ... which is shorter ... not wide angle?

I've spent a lot of time on line trying to figure this out ... can someone steer me to a site that explains this?

Thanks again

E. A. Smith

Mark Sawyer
17-Mar-2007, 13:51
A 105mm Nikon LF lens is "wide angle" because it's amount of coverage is wide enough to cover 4x5 corner to corner, and sharply. The Tessar is not "wide angle" because its coverage is smaller, and it was made for a smaller film format where it would be a "normal" lens, perhaps 2 1/4 x 3 1/4 inch.

Similarly, the 100mm lens off a 35mm camera would have very small coverage, and certainly not be a 4x5 "wide angle".

"Telephoto" is another issue altogether, and is a misunderstood concept by most photographers. It refers to lenses designed to have the angle of view of a long lens, but does not need the extreme bellows draw to focus. (In other words, a 600mm telephoto lens would give the same view as any other 600mm lens, but may only need 400mm of bellows to focus at infinity.)

BTW, if you're on a tight budget, consider the 127mm Ektar and 135mm Optar; both nice coated older lenses. A good book on large format would help with some of the basic concepts. I'd recommend Steve Simmons' "Using the View Camera", and John Schaefer's "Ansel Adams Guide, Book One", which is a bit simpler but covers a wider range of photographic knowledge.

David Karp
17-Mar-2007, 13:54
Thanks for all the suggestions ... but one thing confuses me ...

If a 150mm is "normal" ... (50mm on 35 cameras) ... why is a 100mm not considered wide angle... its 30 percent shorter than the 150 ...

Why are lenses of the same focal length often given different designations ... some 210s described as tele and others are not ...

What makes a 105 Nikor a wide angle but a 100 Tessar ... which is shorter ... not wide angle?

I've spent a lot of time on line trying to figure this out ... can someone steer me to a site that explains this?

Thanks again

E. A. Smith

These are toughies. As I am not a lens expert, there are probably others that can answer better than I am, but I will take a crack at providing my lay person's understanding.

First, there are not too many LF lenses in the 100mm range out there. If we take several lenses that have around a 100mm focal length, it might help. Nikon made a 105mm f/5.6 Nikkor. That lens does not have a large enough image circle to cover a sheet of 4x5 film. It has an image circle of 155mm at f/16. Fuji makes a 105mm Fujinon CM-W that has an image circle of 174mm at f/22. It will cover a sheet of 4x5 with some movement. They used to make a 105mm f/5.6 Fujinon NW that will barely cover 4x5. So, 3 similar focal lengths, 3 different image circles. One covers easily, one barely, one does not cover. These lenses were not designed to cover 4x5 with lots of movement. They are excellent lenses for a MF view camera, and likely were designed for just that sort of application (especially the Nikkor). Its a matter of lens design.

Other lenses were designed as wide angles for use with 4x5 or larger lenses. The 105 120mm and 125mm f/8 lenses mentioned in my prior post, plus the 115mm f/6.8 were designed for wide angle use on 4x5 and 5x7 cameras. The 120mm Nikkor will cover 8x10. These are much bigger lenses than the ones mentioned in the prior paragraph, and are much heavier. They also provide much more movement capability.

The 125mm f/5.6 Fujinon W, or CM-W, or 120mm Schneider APO-Symmar-L are smaller, lighter, and offer much less movement than the lenses mentioned in the prior paragraph, but do cover 4x5 without much movement. On the other hand, they are smaller and lighter then the lenses in the prior paragraph. Again, its a matter of lens design. These are not "wide angle" designs, but the lenses do cover 4x5.

Telephoto lenses are different than long focal lengths. Again it is a matter of lens design. A telephoto lens is constructed so it requires less bellows to focus a given focal length at infinity than would a standard lens design. In addition, the "pivot point" (not the correct term) is located out in front of the lens. So, when you tilt or swing the lens, the image will move, requiring recomposition on the groundglass. With a "standard" design lens, the "pivot point" will be near the center of the shutter. The image will not move nearly as much as it will when applying tilts or swings as happens with a telephoto. The greatest reason to use a telephoto is when you have a camera that does not have enough bellows extension capability to use the focal length you want to use.

I hope this helps a bit.

David Karp
17-Mar-2007, 13:55
Oh yeah,

There are lots of lenses in the 90mm focal length that are considered wide angle lenses for a 4x5, and which offer plenty of coverage plus some movements.

C. D. Keth
17-Mar-2007, 13:56
100mm is a wide angle lens on 4x5. Just because people don't always call it that doesn't amke it true. Large format tends to do without a lot of the characterizations of smaller formats.

Telephoto in large format does not in any way describe the focal length of the lens. Telephoto lenses in lf indicate a particular optical design that requires less bellows extension than a lens of a normal design. A 300mm lens of normal design will require 300mm of bellows to focus at infinity. A telephoto 300mm will require less, so more like 210-220mm of extension.

The tessar is not a wide angle lens because a tessar-design lens has a narrower angle of coverage. You could use it on a 4x5 but the whole frame would not be sharp. To have the whole frame sharp with that lens you would end up using smaller film which would make the angle of view greater than what we would call wide-angle.

Edit: Wow. I must type slow. I thought I was gonna be first to answer all those questions :P

Nick_3536
17-Mar-2007, 14:03
More confusing take the same 105mm lens and mounted it on a smaller format [say 6x7] and it's no longer a wide lens.

A wide focal length is shorter then "normal" for the format.

Brian Ellis
17-Mar-2007, 19:48
"Thanks for all the suggestions ... but one thing confuses me ...If a 150mm is "normal" ... (50mm on 35 cameras) ... why is a 100mm not considered wide angle... its 30 percent shorter than the 150 ... What makes a 105 Nikor a wide angle but a 100 Tessar ... which is shorter ... not wide angle? Why are lenses of the same focal length often given different designations ... some 210s described as tele and others are not ..."

For present purposes there are three types of lens designs, wide angle, normal, and telephoto. These terms are often misused. For example, the term "wide angle" lens is often used synonomously with "short focal length" and the term "telephoto" lens is often used synonomously with long focal length. But these usages aren't technically correct. The term "wide angle" lens refers to a lens design in which the diameter of the circle of good definition and the angle of coverage are greater than a normal lens of the same or similar focal length. So two lenses of the same or close to the same focal length (e.g. 100mm and 105mm in this discussion) wouldn't necessarily both be considered "wide angle" lenses. The dividing line between a "wide angle" lens and a normal lens of similar focal length is to some extent arbitrary and different manufacturers use the term differently (i.e. one might call a lens a lens having a particular circle of good definition and angle of coverage a "wide angle" lens and another might not).

The term "telephoto" lens is a more precise term than "wide angle" lens. The term "telephoto lens" refers to a particular type of lens design in which the lens-to-film distance is shorter than a normal lens of the same focal length. The difference is usually about 25%. The only reason for using a telephoto lens is if the camera's bellows length is too short to accomodate a normal lens of a given focal length. For example, a 300mm normal lens wouldn't be practical to use on a camera with a maximum bellows extension of 12" (300mm) because the lens couldn't focus at anything closer than infinity. But if the 300mm lens was a telephoto design it would be very practical to use with a 12" bellows because the physical extension required to focus at infinity would only be about 225mm and closer focusing would then become feasible.

I could go into more detail, and the above is somewhat oversimplified but hopefully it gives you an idea of what the terms mean.

"I've spent a lot of time on line trying to figure this out ... can someone steer me to a site that explains this?"

I'm sure there must be discussions of this on line but the best discussion I know of is in the book "View Camera Technique" by Leslie Stroebel. That book is excellent for many other reasons and I highly recommend it.

Matus Kalisky
18-Mar-2007, 05:35
Hello, it is nice to see somebody new trying to enter the LF. The confusion is rather standard one. I have started less than a year ago and have spent ~ 3 months to figure out what is what and what would be reasonable to start with.

You mentioned that you like 35mm lenses on small format. In 4x5 it translates somewhere around 115 mm (My "favourite" factor is 3.2). Well - now if you would like to get more advices - it would be usefull if you would also mention what type of photography you do most. Landscapes, architecture, macro, studio, portraits..? You will get different advices not only on the lens but also on the camera.

I may just mention the way I went. I also like the view of 35mm lens and after searching the market I ended up buying (used) Fujinon CMW 125/5.6 which translates to ~ 40mm in small format. This lens with its coverage of 204mm allows for movements wich are more than enough for landscapes (my main concern at that time) and is usually enough for architecture photography. Technically speaking it just allows me for full rise (3.5 cm) on my Tachihara at portrait orintation. Here I touched the second subject - the camera. I wanted to go light and did not have mych money so I decided for Tachihara. It is great camera for landcapes and general photography, but I would look somewhere else if arichitecture (more movements), macro (longer bellows and stability) or portrait (ability to hold longer and havy lens like Heliar 210 or so).

Just for completeness; my setup consists from aforemetioned Fujinon CMW 125/5.6, Geronar II-E 210/6.8 (small, simple, cheap and quite good) and the latest Osaka 400/8 (tephoto design, still managable and at infinity reasonably stable).

Couple words mor about the lenses. As much as I like the view of the 125mm, sometimes it is simpler to cut the sceen a bit down (often means to simplify) and then I go for the 210.

good luck.

Brian Ellis
18-Mar-2007, 06:17
"A 105mm Nikon LF lens is "wide angle" because it's amount of coverage is wide enough to cover 4x5 corner to corner, and sharply."

Sorry but that's not correct. Any lens that adequately covers 4x5 isn't a "wide angle" lens. As I mentioned above, the term "wide angle" lens means a lens whose circle of good definition and angle of coverage are greater than a normal lens of the same focal length. Borrowing from the Stroebel book also referred to above:

"Wide angle lenses are characterized by having greater covering power than normal lenses of the equal focal length. Since covering power is measured in terms of the diameter of the circle of good definiton and the angle of coverage, both of these factors will be relatively large with wide angle lenses. The diameter of the circle of good definition will be considerably larger than the focal length, and the angle of coverage will be considerably larger than 53 degrees, the angle produced when the diameter of the circle of good definition is equal to the focal length. . . . Some lens manufacturers classify lenses with an angle of coverage of 65 degrees, only 12 degrees higher than the 53 degrees that can be expected with normal lenses, as wide angle lenses. Angles of 80 degrees to 100 degrees are more representative of this type of lens. . . . "

Brian Ellis
18-Mar-2007, 06:20
"A wide focal length is shorter then "normal" for the format"

Sorry but this isn't correct either. The term "wide angle lens" isn't the same thing as a short focal length lens.

Nick_3536
18-Mar-2007, 07:02
"Wide angle lenses are characterized by having greater covering power than normal lenses of the equal focal length. "

That sounds like marketing talk to me.

The 150mm Super Symmar XL has far more coverage then normal lenses of the same focal length. But it's angle of view is totally dependent on the format behind it.

Yes a wide angle lens tends to have a higher angle of coverage but it's the format it's stuck on that defines it.

Good defination also varies. The factory claims the G-Claron doesn't cover 4x5 very well. Some people claim it covers far more then 5x7. So is it a wide angle lens? With more coverage then the average 150? Is it a normal 150mm? or is it long because the factory rated spec is so much worse?

C. D. Keth
18-Mar-2007, 09:17
"A 105mm Nikon LF lens is "wide angle" because it's amount of coverage is wide enough to cover 4x5 corner to corner, and sharply."

Sorry but that's not correct. Any lens that adequately covers 4x5 isn't a "wide angle" lens. As I mentioned above, the term "wide angle" lens means a lens whose circle of good definition and angle of coverage are greater than a normal lens of the same focal length. Borrowing from the Stroebel book also referred to above:

"Wide angle lenses are characterized by having greater covering power than normal lenses of the equal focal length. Since covering power is measured in terms of the diameter of the circle of good definiton and the angle of coverage, both of these factors will be relatively large with wide angle lenses. The diameter of the circle of good definition will be considerably larger than the focal length, and the angle of coverage will be considerably larger than 53 degrees, the angle produced when the diameter of the circle of good definition is equal to the focal length. . . . Some lens manufacturers classify lenses with an angle of coverage of 65 degrees, only 12 degrees higher than the 53 degrees that can be expected with normal lenses, as wide angle lenses. Angles of 80 degrees to 100 degrees are more representative of this type of lens. . . . "

If you take that quote in context, yes, it is correct. A 105mm that sharply covers 4x5 will be a wide angle lens on that format. The reason it was stated like this is that it was compared to a tessar of the same focal length that will illuminate the format, but not cover it sharply. For this reason the tessar was not called a wide angle lens on 4x5 but the Nikon was.

Brian Ellis
18-Mar-2007, 13:25
"That sounds like marketing talk to me"

Why? It's a quote from a book. The author isn't selling lenses.

"The 150mm Super Symmar XL has far more coverage then normal lenses of the same focal length. But it's angle of view is totally dependent on the format behind it. Good defination also varies. The factory claims the G-Claron doesn't cover 4x5 very well. Some people claim it covers far more then 5x7. So is it a wide angle lens? With more coverage then the average 150? Is it a normal 150mm? or is it long because the factory rated spec is so much worse."

So what's your point, that there's no such thing as a wide angle lens because different people have different ideas as to what constitutes an acceptable image circle? Or that there's no such thing as a wide angle lens because the angle of view varies with the film format? Or that Stroebel doesn't know what he's talking about?

I think we all understand that angle of view varies with film size. Normally angles of view are quoted with reference to a particular format. For example, the angle of view of a 150mm Super Symmar XL would normally be quoted with reference to 4x5 film since that's the film size for which it's designed to be used. We know that if we could put the Super Symmar XL on a 35mm camera the resulting angle of view would be far narrower than it is with 4x5 film. But we wouldn't normally base its angle of view on 35mm film because that isn't the film format on which the lens is intended to be used. But so what?

People presumably have found that the G Claron will cover more than the factory specs indicate either because they are using smaller apertures than the aperture the factory used as the basis for its image circle specs or because their ideas of good definition vary from the factory's or both. I used a 210mm G Claron with 8x10 film even though the specs don't show a 318mm circle of good definition. But I stopped down to at least f22 and usually smaller, which improved definition at the edges. I also was making contact prints so I didn't have any magnfication factor to worry about. And perhaps the factory just had a more stringent definition of "acceptable" than I did.

Ole Tjugen
18-Mar-2007, 14:41
There are two basic concepts which I can't see have been defined in this thread:

"Angle of View" depends on the focal length of the lens and the size of the film. All 100mm lenses will give the same AoV on a 4x5" film - provided that they have enough coverage that they can actually give an image all the way across the film. And that brings us to:

"Angle of Coverage" depends only on the lens construction (and the f-stop). It defines the total angle where the lens will give a good definition on film, regardless of the film format. Common lens types have different AoC: Telephoto lenses can have around 30 degrees, Tessars typically a little less than 60 degrees, Plasmats up to 70, and true wide angle lenses around 100 degrees. Sometimes more, sometimes less.

Nick_3536
18-Mar-2007, 14:49
"That sounds like marketing talk to me"

Why? It's a quote from a book. The author isn't selling lenses.



No but it sounds like he is explaining how the lens companies label things.





So what's your point, that there's no such thing as a wide angle lens because different people have different ideas as to what constitutes an acceptable image circle? Or that there's no such thing as a wide angle lens because the angle of view varies with the film format? Or that Stroebel doesn't know what he's talking about?


My point is a wide angle lens depends on what you do with it. Not on it's coverage. Assuming the lens covers the format then any excess coverage isn't part of the question.

A wide angle lens has a wider view.

Ole Tjugen
18-Mar-2007, 14:50
...I've read "multiply your favourite 35mm lens by 3 and that's the focal length you need for 4x5"

I use a 35mm as my "normal" lens ... so that seems to indicate a 105mm. But then this issue of coverage and movement comes up ...


That "multiplication factor" should be taken with a pinch of salt.
First of all, the aspect ratios are very different between the narrow 35mm frame and the more square 4x5". Second, the "normal" focal length is often defined as "equal to the film diagonal", which means that 35mm has a "normal focal length" of 43mm, not 50mm. 4x5" film is about 153mm, which is about what many consider as "normal" - at least the lens manufacturers seem to favor that length. 150/43 is about 3.5, not 3.

By using that number you end up with a focal length of around 120mm to get about the same as a 35mm lens on 35mm film. A 100mm lens will give something similar to 28mm on 35mm, which I'm sure you will agree is a whole lot wider!

In the 120mm range there are a lot of lenses which will cover 4x5" with room for movements, and moving the upper limit to 135mm really expands the possibilities.

Brian Ellis
18-Mar-2007, 18:59
No but it sounds like he is explaining how the lens companies label things.



My point is a wide angle lens depends on what you do with it. Not on it's coverage. Assuming the lens covers the format then any excess coverage isn't part of the question.

A wide angle lens has a wider view.

e. a. smith
18-Mar-2007, 20:56
Wow ... thanks for all the responses ...

I'm not REALLY stupid but .....

I checked out the link to the lens chart and don't understand some of the specs ... references to movements for portrait being one of them ... I take it that a lens is not just a lens in terms of movement ... that some sorts of photography require more movement than other types ... but why the diferent specs for portrait movement

The OTHER thing I'm stumbling with is bellows extension in longer lenses. I've owned 6 Mamiyas with focusing bellows and the bellows is contracted for distance focus and expanded for closer focus ... much like adding extension tubes in 35mm .... but several posters mentioned needing longer bellows extensions to focus longer lenses . That seems to me to be backwards ... what am not understanding here ...

Several posters suggested knowing my camera and the type of photography I intend using it for would help with lens recomendations .... I have been given a Linhof Color 45s by one of my customers and an Omega D5 Variable by another ... plus three great Schnieder EL lenses ...

This camera is strictly for me ... any commercial work I do now is digital ... I want to do B+W studio portraits and figure studies ... so I need X-sync ... and I want to do outdoor work that would not be landscapes as much as isolating elements in a scene ...

My 35 kit is normally 24 ... 35... and either85, 90 or 105 depending upon camera brand.
I seldom use "normal" lenses ...

From what I've read in the posts I'm thinking 120-125 and a 210. Would a shorter lens that converts to 300-315 be a good idea? I assume that any softness in the converted lens would be compensated for by neg size and I use 600 WS Photogenics
so smaller aperature shouldn't be a problem.

I guess as soon as I get lenses I'll invest in the recommended books.

Again ... thanks for all the great input.

E.A. Smith
Chaffeys Lock Ontario Canada

Ole Tjugen
18-Mar-2007, 22:06
To begin from the top:

"Portrait" and "landscape" are not only possible subjects, but also names for vertical and horizontal orientation respectively. Since portraits are often printed with the vertical side a little longer than the horizontal, this is called "portrait orientation". Since the image area of the film is not square, there is a little difference in how much movements can be applied in horizontal and vertical orientation.

Unlike most lenses for smaller formats, LF lenses do not have a fixed "flange focal distance". On a 35mm camera it's easy - a 25mm lens, a 50mm lens and a 100mm lens are all attached to the camera at the same point, and will focus at infinity with the focus mechanism turned all the way in.
LF lenses are a lot simpler - there is no fixed distance at all! So with a 90mm lens you need to extend the lens enough to put the lens node at 90mm from the film plane to focus at infinity; with a 150mm lens you need 150mm, and so on. If you want to use a lens with longer focal length than 400mm on the Linhof Color, you will need a telephoto lens. That does not merely mean "long focal length"; it really means that the node is somewhere outside the lens itself - right out in open air in front of the lens. That again means that the mounting flange is quite far behind the node, so you need less bellows length.

Most shutters made after WWII have X-sync. Don't worry about that unless you want to shoot antiques.

A "shorter lens that converts to 300-315" would be a 180mm f:5.6 Symmar. That converts to a 315mm f:12 by removing the front cell. However it requires quite a bit more extension than 315mm to focus that thing at infinity! Taking portraits with that on the 40cm bellows of the Linhof could well be difficult. Apart from that little "niggle", I'm a great fan of convertible lenses in general and Symmars in particular.

Having done quite a bit of portrait photography earlier (admittedly with MF), I wouldn't like to be sitting for a portrait with a photographer who blasts off a strong enough flash to expose at f:32. If you are sure you have enough light, I recommend you test them out from the "receiving end" too. :)

e. a. smith
18-Mar-2007, 22:19
Ole ....

Thanks so much ... I think I'm starting to grasp this a bit .... maybe I AM stupid ... I should have figured out that landscape and portrait reffered to the film orientation ...

And that's a good point about flashes ... I normally shoot studio stuff at f-8 so I assumed that a converable lens at f-12 would be about a stop less light ... I hadn't considered closing down for sharpness. My bellows extends to about 13 inches ... would that let me focus a 300+ convertable lens at say 10-12 feet? I sort of like the idea of one lens doing two jobs ...

Thanks

E. A. Smith

Ole Tjugen
19-Mar-2007, 14:41
A 300mm converted lens won't even focus at infinity with 13 inches of bellows, much less 10-12 feet!

The document HERE (http://www.schneiderkreuznach.com/archiv/pdf/sr_5.6_a.pdf) shows the necessary extension with converted Symmars - other convertibles are very, very similar. To focus a 315mm f:12 rear half of a 180 Symmar at 3m (10 feet), you need 48cm bellows extension...

I like "dual-purpose" lenses myself, and use 180, 210, 240 and 300mm convertible SYmmar lenses. I have even used a 120mm Angulon as "convertible", when I found I needed a 200mm lens and only had short lenses at hand!

Carsten Wolff
19-Mar-2007, 23:18
You could of course just try it out stopped down.... But I agree with Ole, Kirk and Mark and others. You're likely to be unhappy with the coverage. I'd sell the 100mm Zeiss Tessar and use the money to perhaps get a later model 90mm Angulon (non Super- if you want to save weight and money) This a harmless looking, but fine lens (with reasonable, but not spectacular extra cover). Any other modern 90mm will do, too and have more coverage, (but also weigh a fair bit more; Congo being the exception perhaps).
Then get above mentioned 135 Symmar, or Symmar-S and if you still have money left, any 200, 210mm, or thereabouts (e.g. a Kodak Ektar) and you're set! 300, esp. convertible doesn't sound as if it's gonna work either; you'll be fine with the above spread anyway.

Alan Davenport
20-Mar-2007, 11:07
"The 150mm Super Symmar XL has far more coverage than normal lenses of the same focal length.

I love these threads where everyone argues about the definitions of technical terms; they almost invariably end with the responders arguing semantics instead of responding to the original question.

I don't know who wrote the book (quoted earlier) but there's another -- "normal lens" -- which is of course defined by the film format and has no focal length until defined by the film. It appears the book's author incorrectly used "normal lens" to refer to some type of lens construction.

It's probably more appropriate to refer to lenses as short, long or normal lenses, rather than using terms such as wide angle, which term can obviously be applied in various ways, not all of them technically correct.

e.a., the 100mm Tessar was probably made for use with medium formats, like 2x3. It might possibly (just barely) cover 4x5 when stopped down, but it may not allow any movements and might be soft in the corners. A recessed board won't improve the lens coverage issue; all a recessed board does is reduce the amount that the bellows has to be compressed with short lenses.

You can buy a 90mm f/8 Super Angulon for around $300 these days, which will be sharp to the corners and offer lots of movements. A 90mm lens, on 4x5 film, is sort of equivalent to a 28 on 35mm film, or even a 24, depending on who you talk to; comparing lenses on formats with different aspect ratios is at best imprecise.

Dave Moeller
20-Mar-2007, 15:54
Just because I want to make your life more difficult (no, not really), I might throw one more spanner into the works. Personally, the trick of multiplying focal lengths doesn't work at all for me. In small format, I like wide (and even exteme wide) angle lenses. In medium format I prefer normal to slightly long lenses. With each increase in format I find that I like longer lenses, so by the time I get to 8x10, my favorite length is 480mm.

Luckily, if you buy a large format lens and find that you don't like it, you can usually sell it for close what you paid for it. So it's worth experimenting a bit, if you don't mind the effort of selling stuff.

Having said this, I strongly recommend that you buy one, or at most two, lenses and just use them for a while. Avoid collecting many lenses at first...that way lies madness. (I speak from experience...)

Best of luck.