ULF shooters.Lens mount questions please !

[Tri Tran]

Hi ULF shooters,
Beside a custom order a flange for this beast which I might have to do so . Just received A 24 inches/F4.5 Petzval lens weighted 25lbs, 25 inches long and 8 1/2 inches diameter Flange threats (but NO flange) .In the mean time I would like to try it on the 8A Century camera . What's the best way to mount it? Some height adjustment accordingly with the camera if possible ( Just so to let you know I also have a tripod with gear column and a Majestic head for my 20x24) .How did the old folks mount the mammoth lens on the camera back in the days? A scan or a drawing it sure helps if you can.Thanks a bunch.

[Pete Roody]

At a minimum, you can thread an aluminum board and mount the lens directly to the board. I am assuming you have 9x9 boards.

[GPS]

Hi ULF shooters,
Beside a custom order a flange for this beast which I might have to do so . Just received A 24 inches/F4.5 Petzval lens weighted 25lbs, 25 inches long and 8 1/2 inches diameter Flange threats (but NO flange)
...
How did the old folks mount the mammoth lens on the camera back in the days? A scan or a drawing it sure helps if you can.Thanks a bunch.

Obviously, if the lens has flange threads, they mounted the lens with a flange...
You should do the same - with a custom order flange as you suggest.
Never mount this lens of 25 lbs to an aluminum board with a threaded edge - unless you're a fool and the "board" is at least 15mm thick that is...

[benrains]

If I remember correctly, the 8A takes 10x10 boards. A 9x9 board isn't going to cut it with a 8.5" diameter lens unless it's made out of something like steel. That said, I'm not sure I'd trust mounting 25 lbs of lens on a wooden 10x10 board even with a flange--nor would I necessarily trust the mounting hardware on the front of the 8A to hold up under that weight (especially with the torque of such a long lens.)

For starters I'd second the suggestion of getting a machined metal threaded lens board of a thickness comparable to the 8A lens boards. My 9x9 boards are around 11-12mm thick. I really don't think you'll have much trouble with aluminum, but you can ask the machinist for suggestions on an alloy with suitable strength. You could also opt for having it machined from a brass alloy or something like P20 steel, but those will of course add more weight.

I'd really love to see a picture of that monster.

[eddie]

WOW! TT i am going to call you....

i have my local machine shop make me threaded aluminum lens boards for my monsters without flanges.

i just picked this one up today. the hole in the lens board is 6 1/2 inches. the lens is a 22 inch lens and weighs 16 pounds. it is on an 8x8 inch lens board.

i find that even if you have the flanges for these lenses they quickly become too big for the "regular" lens boards. even 10x10 inch boards are not big enough to accommodate the flanges. i know this lens would never go on a 8x8 board with a flange. even 9x9 would be pushing it.

the most difficult time i have is running out of bellows. that is why i use the 8x10 and 11x14 deardorff studio cameras....plenty of bellows. this lens needs 46 inches on tight head shots and about 36 on shots just under 3/4. (too much for 8x10 century cameras)


cheers

eddie

edit. this photo is of a similar sized 25 inch lens. no worries about the aluminum....worry more about your screws pulling out of the front standard of your camera....LOL

[eddie]

two for fun. mounted on my DD 1114

[Pete Roody]

Don't underestimate the strength of aluminum. 6061 Alloy has an equivalent strength to structural steel (35-40 ksi yield). A 12"x12"x1/2" sheet costs about $60 from McMaster Carr. All you need is a machine shop to cut it to size and thread it.

[BarryS]

I agree with Eddie about getting a machine shop to do a one piece threaded lens board. I think the brass retaining plate at the top of the 8A front standard is only held in place with screws (at least there are no bolt ends on the inside of my 8A front frame). For a 25 pounder, I'd seriously consider replacing those screws with long bolts that go all the way through the standard and capping off the bolts with large washers under the nuts.

[Tri Tran]

Thank you all for your input and ideas. You guys are great!
Eddie, your lens looks very Sexy!
Before decide to build something solidly, I woud like to try the least expensive way to get the lens on the camera to see if I like the looks of its perform or it's a show piece. How about a craddle with some height adjustment for the lens to sit on and the camera will meet the lens like this picture.


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This lens make my 27 inches Cooke lens looks like a Dwarf and on the right is a Hermgis Eidoscope #2 for your to compare.



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Anything from 24 inches FL plus for head and shoulder shot to use with the Century 8A Double Bellow is still a liitle short for few inches as Eddie stated . That's why the original owner Mr Robinson was planned and custom order this Iron casted top hat board to use for this outfit. Smart man!


This one especially for Hugo and Hass . My finger crossed for Chamonix can come up with the new ideas of the 20x24 box camera for these Mammoth lens to shoot with . Totally functionality for easy assembly and disassembly when on field needed. That's what the beauty of Petzval lens for , not in the studio at least for me.



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For security! This picture showed the back of the front camera that I have it installed a framing bracket to reinforce the front support.



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The 27 Inches Cooke lens works great on the 8A for the last at least 70 years and has survived a several earquakes here in California.I'm looking forward to the next Beast on the camera and show you guys some pictures taken with it. Any others ideas please keep me posted.Thanks so much.

[Tri Tran]

A Top Hat Lens board was made by Taylor Hobson to use with this outfit as you see it gains another 4-5 inches bellow drawn which is perfect for head and shoulder on the 8A.


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