| View previous topic :: View next topic |
| Author |
Message |
rocklaneeast
Joined: 28 Oct 2002
Posts: 18
Location: Newcastle N.E.England
|
 Posted: Sat May 03, 2003 7:29 pm Post subject: |
 |
|
Can an aerostigmat be fitted to an anniversary speed graphic or are there not enough bellows thanks g
|
|
| Back to top |
|
 |
RichS
Joined: 18 Oct 2001
Posts: 1468
Location: South of Rochester, NY
|
| Posted: Mon May 05, 2003 4:23 am Post subject: |
|
|
| Quote: |
On 2003-05-03 12:29, rocklaneeast wrote:
Can an aerostigmat be fitted to an anniversary speed graphic or are there not enough bellows thanks g
|
I can possibly offer some answers.
There's two considerations to using the aerostigmat on the Speed. Size and focal length.
I would think you could use a 12 inch lens as long as you don't intend to do close-ups. An Anniversary is supposed to have 13 1/2 inches of bellows, so you could easily focus at infinity and quite a bit closer.
Next is physical size. My Aerostigmat 12 inch is the only lens I have mounted on a 6x6 lens board for sole use on an 8x10 camera because it's just too big for my 4x5 cameras. It measures 3 inches in diameter for the rear cell and more than 4 3/4 inches for the Alphax shutter it's mounted in. The mount hole is approximately 3 1/4 inches. That would barely fit your 4 inch lens board and you might be able to squeeze the 4 inch mounting flange on the front of the board, but maybe not? I decided not to even try...
So it will fit for focal length, but only a maybe for size...
[ This Message was edited by: RichS on 2003-05-04 21:24 ] |
|
| Back to top |
|
|
Dan Fromm
Joined: 14 May 2001
Posts: 2144
Location: New Jersey
|
| Posted: Mon May 05, 2003 2:51 pm Post subject: |
|
|
| Quote: |
On 2003-05-04 21:23, RichS wrote:
| Quote: |
On 2003-05-03 12:29, rocklaneeast wrote:
Can an aerostigmat be fitted to an anniversary speed graphic or are there not enough bellows thanks g
|
I can possibly offer some answers.
There's two considerations to using the aerostigmat on the Speed. Size and focal length.
I would think you could use a 12 inch lens as long as you don't intend to do close-ups. An Anniversary is supposed to have 13 1/2 inches of bellows, so you could easily focus at infinity and quite a bit closer.
Next is physical size. My Aerostigmat 12 inch is the only lens I have mounted on a 6x6 lens board for sole use on an 8x10 camera because it's just too big for my 4x5 cameras. It measures 3 inches in diameter for the rear cell and more than 4 3/4 inches for the Alphax shutter it's mounted in. The mount hole is approximately 3 1/4 inches. That would barely fit your 4 inch lens board and you might be able to squeeze the 4 inch mounting flange on the front of the board, but maybe not? I decided not to even try...
So it will fit for focal length, but only a maybe for size...
[ This Message was edited by: RichS on 2003-05-04 21:24 ]
|
Rich, physical size need not be a deterrent.
My 12"/4 Taylor Hobson tele lens' od at the rear is 80 mm. Mounting it on a 2x3 Pacemaker board (63.5 mm x 63.4 mm) looks, at first glance, impossible. The late Steve Grimes did the job by making a stepped bushing that screws into the back of the lens' barrel. The back of the bushing goes through the board and is held to it by a retaining ring, as usual. Of note, the step leaves room for the "ears" on the lens board sliders.
I'm thinking about having my 6"/1.9 Dallmeyer Super Six -- od at the rear 75 mm -- put on board the same way.
Putting a lens on board this way increases extension a bit, not always a bad thing. Although, since the film-to-rear element distance of the 12" is ~ 85 mm at infinity, it really doesn't need any added extension to work on a 2x3 Pacemaker Speed. The Super Six isn't a tele lens, will probably gain a little from the added extension.
Another handy trick to extend the usefulness of old cameras, eh?
Cheers,
Dan |
|
| Back to top |
|
|
rocklaneeast
Joined: 28 Oct 2002
Posts: 18
Location: Newcastle N.E.England
|
| Posted: Mon May 05, 2003 4:13 pm Post subject: |
|
|
Thanks for your comments
I already have an aero ektar 178 2.5mm
on the speed graphic. Ive managed to mount it OK
The aerostigmat is the same size as the ektar
but the glass is lighter. I should have no problems with the board because ive already worked out how to fit it.
Unfortunately I want to use the lens closer than infinity. Id settle for whole 6ft person in frame down to head shoulders if possible.
My immediate solution is a number one close up filter or some how getting a little extension on the mount as described by Dan Fromm
Any comments on my solutions.
But once again DF and RS thankyou for your help |
|
| Back to top |
|
|
Nick
Joined: 16 Oct 2002
Posts: 494
|
| Posted: Mon May 05, 2003 5:19 pm Post subject: |
|
|
I've got a big process lens. When I say big I mean big. I made a custom lensboard that's thicker then normal. The lensmount is mostly on the lensboard but not all. The mount is drilled for five screws but I've got just three over wood. The board I made is 3/4" thick and could be easily thicker. I don't need the extension but wanted all the wood I could get for the screws to bite into.
Depending on how much extension you need just a thick board might be enough. |
|
| Back to top |
|
|
Dan Fromm
Joined: 14 May 2001
Posts: 2144
Location: New Jersey
|
| Posted: Mon May 05, 2003 7:42 pm Post subject: |
|
|
| Quote: |
On 2003-05-05 09:13, rocklaneeast wrote:
Thanks for your comments
My immediate solution is a number one close up filter or some how getting a little extension on the mount as described by Dan Fromm
Any comments on my solutions.
But once again DF and RS thankyou for your help
|
Not to be frivolous, how about PVC sewer pipe?
I have a 210/9 Konica Hexanon GRII (long name, longer lens) adapted to mount in front of a #1 shutter. The adapter is cup-shaped. It screws into the shutter, the lens screws into it. The front section that accepts the lens is over an inch deep. No reason why it could't have been made deeper except the desire to minimize vignetting. As is, it covers 2x3 just fine, almost certainly won't cover 4x5. Needs a bigger leaf shutter or none at all to cover 4x5.
Not quite what you need, but I think you'll see the idea. Steve charged $75 for it, less for the stepped mounting whatsit for my 12"/4. He's dead but SKGrimes lives on. I spoke with Adam, who's now in charge, just this morning. You might ask him what he can do for you.
Cheers,
Dan |
|
| Back to top |
|
|
RichS
Joined: 18 Oct 2001
Posts: 1468
Location: South of Rochester, NY
|
| Posted: Tue May 06, 2003 3:00 am Post subject: |
|
|
Well, I really don't know, but as I remember the Aero Ektars were a completely different design than the Aerostigmat? The Aeorostigmat is more of a pancake like the Commercial Ektars (Okay Dan, let us know what designs they are  ) But you may still be right about basic sizes?
As far as how close you could get, I'm sure someone here could do the math, or offer the equation? I never remember, even where to look it up... The only way I could tell would be to put a 12 inch on a GVII since my Crowns & Speeds have an inch less bellows than an Aniversary. I would just go ahead and do that, but things are a bit crazy at the moment and tight for time...
And a lot of people frown verbally at close-up lenses but I've used them many times and always been happy with the results...
Dan... I like your mounting method and it gives me an idea. As long as the lens has a threaded rear cell that would accept a filter, it would be fairly easy to hook up a filter ring into a lens board for a front mount. May take a little thought to handle the weight of such a lens as an Aerostigmat, but it would give at least two inches of extension. And the thicker board, and on, and on... And the PVC pipe has been brought up here before but I haven't heard anyone doing it yet. I wanted to but I never did manage to pick up the 1000mm lens I wanted
I suppose the bottom line is; if there's a will, there's a way... But hanging all that weight two or three inches in front of the front standard is something else?
|
|
| Back to top |
|
|
Les
Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI
|
| Posted: Tue May 06, 2003 4:04 am Post subject: |
|
|
Well here's the formulas. I'm going with the alleged 13.5" of bellows on an Anny which, to my failing memory sounds about right.
The formula is s=s'f/s'-f where s is the object distance and s' is the image distance, and f is the focal lenght
s=(13.5x12)/(13.5-12)
s=162/1.5
s=108 inches or 9 feet.
The angle of view can be found by dividing one of the dimentions of the film (horizontal, vertical or diagonal) by the focal lenght to find the quotient. Then look the quotient up in Graphic Graflex Photography 10th edition.
Okay it was said somewhere up there of a head shot so let's assume this camera will be used vertically. So 5/12= 0.416. The closest the book has is 24° which is 0.4251.
The book also states that you can calculate the dimention of the field at any given distance. So we should be able to find the height of the full frame at it's closest distance. The formula is
Distance X Quotient= Subject Dimention.
9 feet x 0.416= 3.75 feet or a rough 3/4 shot (knees up) on a 6 foot person.
For those of you still with me..... What if we wanted to reverse the situation and state that we wanted a shot of this guy with a 2 foot vertical distance-- a sloppy head shot, or a good head shot with lots of room at the top for a hat.?
Thus 2 feet/0.41666=4.8007feet away from the camera or close to half of what we had before.
Now we have the object distance, we need the image distance or bellows lenght. Since lenses don't know which end is which, the same formula applies, just switch the s and the s'. After converting the 4.8 feet to inches....
s'=s x f/s-f
s'=(57.6" x 12)/ (57.6"-12)
s'=691.2/45.6
s'=15.15inches
Now all of these distances are from the rear nodal point, which for most normal lenses are usually close to the flange, but I'm not going to guarrantee that for a special application military lens. |
|
| Back to top |
|
|
RichS
Joined: 18 Oct 2001
Posts: 1468
Location: South of Rochester, NY
|
| Posted: Tue May 06, 2003 5:09 am Post subject: |
|
|
Wow, thanks Les. I knew that someone had that info. Now if I could just remember where I save it this time for next time since I could never remember the calcs...
|
|
| Back to top |
|
|
Dan Fromm
Joined: 14 May 2001
Posts: 2144
Location: New Jersey
|
| Posted: Tue May 06, 2003 3:19 pm Post subject: |
|
|
| Quote: |
On 2003-05-05 20:00, RichS wrote:
Well, I really don't know, but as I remember the Aero Ektars were a completely different design than the Aerostigmat? The Aeorostigmat is more of a pancake like the Commercial Ektars (Okay Dan, let us know what designs they are ) But you may still be right about basic sizes?
Dan... I like your mounting method and it gives me an idea. As long as the lens has a threaded rear cell that would accept a filter, it would be fairly easy to hook up a filter ring into a lens board for a front mount. May take a little thought to handle the weight of such a lens as an Aerostigmat, but it would give at least two inches of extension.
I suppose the bottom line is; if there's a will, there's a way... But hanging all that weight two or three inches in front of the front standard is something else?
|
The Vade Mecum, also sometimes known as the source of confusion and misinformation, says the Aerostigmat is a Tessar or a triplet or something. By it the 7" and 12" AeroEktars are 7 element 4 group gauss types.
The adapters the late Mr. Grimes made for me for putting barrel lenses (4"/2 and 12"/4 Taylor Hobsons) in front of boards are much sturdier than filter rings. Wall thicknesses are on the order of 2 mm. I think there's a hint there.
Funny you should worry about the effects of a heavy lens with center of gravity far in front of the front standard. I sent my 2x3 Speed to Mr. Lustig last week. When we talked things over, he strongly advised me to ask him to put a support on the front rail's front crossbar to hold the 12"/4 up. I asked him to do it. More on that point, yesterday I talked with Adam Gau, who's now running SKGrimes. One of the topics was what to do with my 3 1/5 pound 6"/1.9 Super Six. He suggested that I ask him to make a support for it to relieve stress on the front standard. That's two strong hints from people who know the equipment.
Sometimes, even if there's a will there's no way. I've fantasized putting a 24" barrel lens at the end of a piece of pipe on my 2x3 Speed. Physically possible, I suppose, but I don't see how to avoid severe mount vignetting. Some things really aren't meant to be.
Cheers,
Dan |
|
| Back to top |
|
|
rocklaneeast
Joined: 28 Oct 2002
Posts: 18
Location: Newcastle N.E.England
|
| Posted: Tue May 06, 2003 4:57 pm Post subject: |
|
|
Thanks again for the input everyone
I see clearly what the problems are and what the possible solutions are.
Just to clarify. I have an aero ektar on the SG and have no problems with that, its weight causes no problem as far as I can see.
The aerostigmat f5 is exactly the same size barrelwise as the ektar but the glass is lighter so I expect no mounting problems.
I bought the aerostigmat for head/shoulders shots and also because it wasnt radio active
The close up lens with a little front extension seems the first option
thanks all
g |
|
| Back to top |
|
|
RichS
Joined: 18 Oct 2001
Posts: 1468
Location: South of Rochester, NY
|
| Posted: Wed May 07, 2003 2:31 am Post subject: |
|
|
| Quote: |
On 2003-05-06 08:19, Dan Fromm wrote:
The Vade Mecum, also sometimes known as the source of confusion and misinformation, says the Aerostigmat is a Tessar or a triplet or something. By it the 7" and 12" AeroEktars are 7 element 4 group gauss types.
The adapters the late Mr. Grimes made for me for putting barrel lenses (4"/2 and 12"/4 Taylor Hobsons) in front of boards are much sturdier than filter rings. Wall thicknesses are on the order of 2 mm. I think there's a hint there.
Funny you should worry about the effects of a heavy lens with center of gravity far in front of the front standard. I sent my 2x3 Speed to Mr. Lustig last week. When we talked things over, he strongly advised me to ask him to put a support on the front rail's front crossbar to hold the 12"/4 up. I asked him to do it. More on that point, yesterday I talked with Adam Gau, who's now running SKGrimes. One of the topics was what to do with my 3 1/5 pound 6"/1.9 Super Six. He suggested that I ask him to make a support for it to relieve stress on the front standard. That's two strong hints from people who know the equipment.
Sometimes, even if there's a will there's no way. I've fantasized putting a 24" barrel lens at the end of a piece of pipe on my 2x3 Speed. Physically possible, I suppose, but I don't see how to avoid severe mount vignetting. Some things really aren't meant to be.
Cheers,
Dan
|
I thought you might look that up I suppose that one of these days I'll look into basic lens designs so I have some idea what people are talking about when they mention the names. Some of the concepts are easy, bt it takes me a while to associate a name to something...
I never meant to suggest that the filter ring mount was as good as something made by SKGrimes. It was just a quick thought I had from your description as a possible 'quicky' way to mount a lens, for testing more than anything else. I sure wouldn't trust one of these heavy lenses to that kind of mounting as I'm sure something would have to be glued into the board without a proper flange. Okay, wait a second here. What about a large flange screwed into the board and then filter adapter rings to mount various lenses? Could even mount a Packard shutter behind the board for barrel lenses... Another idea I'll never get around to playing with...
There's a question for a Graflex guru (ex-employeee). Did they ever do stress tests to see how much weight they could handle at the lens board? I sure don't hold it against the Graphics. Even my 8x10 doesn't look like it would handle that much weight out in front of the lens board. Bigger doesn't always mean stronger...
A 24" on a 2x3? I'm starting to think you might be worse than me? I'd be happy with a 1000mm on a 4x5. How about a square extension screwed to the outside of a double-thick lens board, also with a square hole drilled in it as large as possible? I know it doesn't have the wood boards as the GVII or C, but you could screw two boards together, front to front so the edges stick out towards the front. Then screw thin wood (brass, aluminum) to the four sides going to another board that would actually mount the lens. That might help fill in the corners?
Never mind, my brain is only semi-functional after a long and hot day of hard labor in the gardens...
And there's another remark about radioactive lenses... I've been trying to get my hands on one for a long time now...
|
|
| Back to top |
|
|
Dan Fromm
Joined: 14 May 2001
Posts: 2144
Location: New Jersey
|
| Posted: Wed May 07, 2003 2:04 pm Post subject: |
|
|
[quote]
On 2003-05-06 19:31, RichS wrote:
| Quote: |
A 24" on a 2x3? I'm starting to think you might be worse than me? I'd be happy with a 1000mm on a 4x5. How about a square extension screwed to the outside of a double-thick lens board, also with a square hole drilled in it as large as possible?
And there's another remark about radioactive lenses... I've been trying to get my hands on one for a long time now...
|
The problem with long lenses on short little cameras is that the camera's front standard will cause vignetting. By similar triangles, if the image circle at the film plane's diameter is 110 mm (conservative for 2.25 x 3.25, but still ...) and the bellows is stretched all the way (extension = ~ 225 mm) and the lens' f.l. is 1000 mm, the round hole in the lens board's diameter has to be ~ 85 mm. Now, my little 2x3 Speed's front standard's throat is a lot smaller than 85 mm. I think the rig described above will illuminate a 60 mm circle on film. Bigger than 24 x 36, which fits in a 43 mm circle, but not big enough.
As I said, some things just aren't meant to be. There really are geometrical limits.
About radioactive lenses, all it takes is money. There's usual several 7"/2.5 AeroEktars on eBay.
Cheers,
Dan |
|
| Back to top |
|
|
Les
Joined: 09 May 2001
Posts: 2682
Location: Detroit, MI
|
| Posted: Wed May 07, 2003 2:25 pm Post subject: |
|
|
"About radioactive lenses, all it takes is money. There's usual several 7"/2.5 AeroEktars on eBay."
Hmmmmm........
API. Dateline April 1, 2004. Graphex Inc., a contractor under the Bechtel group has decided to use the weapons grade thorium found in Iraq to reproduce the rear elements for the World War II era Aero Ektar, a rare and coveted lens sought out buy photographers and artists for it's sharpness and contrast......  |
|
| Back to top |
|
|
RichS
Joined: 18 Oct 2001
Posts: 1468
Location: South of Rochester, NY
|
| Posted: Thu May 08, 2003 3:11 am Post subject: |
|
|
Dan: Is there a simple equation you use to find out the vignetting in such a case? I know I could get out the graph paper and old geometry books, but asking is a whole lot easier
Here's another thought. Forget folding the camera up and put a larger front standard on it like from a 4x5? Umm, and bellows I suppose, and something larger to hold the new standard like the door from a 4x5... How 'bout using a 4x5 with a 2x3 back?
Les: So where can one buy one of these new lenses?
Another thought. If thorium makes a better lens, and I'm going to recement that 305, then I could just mix the ash from an old gas lamp mantle with the cement and have a thorium lens!
And I know it only takes money. There's enough people around happy to take all I have and more... Since the most popular lens seems to be the 7" and it doesn't cover 4x5 (or does it?), I can't see the investement at current prices just to have a glow-in-the-dark paper weight. But I'll find one someday when I have the extra money. And by the time I have extra money....
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
