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Ed Vatza
24-Jan-2019, 06:43
My Wista 45DX has a 12" bellows. That translates to 305mm. That's pretty tight if I want to use a 300mm lens. I'm wondering if I 10mm extension lens board would give me enough play or if I need to go longer? I want tom have enough play with a 300mm without having a monstrosity hanging on the front standard. Thanks.

Ed

minh0204
24-Jan-2019, 07:00
Quite tight, but most 300mm lenses have a flange-focal distance of less than 300mm, so you'll have a centimeter or two of wiggling room by default, which means you can focus as close as ~6 meters. A longer top hat board will allow closer focus, but is somewhat annoying to carry around. Just get a lens to play with on a flat board first and if you really feel hindered by the focusing, get a top hat. You may actually find 210mm lenses fully adequate at closer focus distance.

Tin Can
24-Jan-2019, 07:28
I use a '20mm/55mm/75mm Extension Lens Board For Linhof Technika Wista ShenHao Chamonix'.

drew.saunders
24-Jan-2019, 10:47
When I was using a Tachihara with ~12" of bellows, I chose the Fujinon-C 300/8.5 (282.3mm FFD) over the Nikkor-M 300/9 (290.0mm FFD) for that extra 7mm of "built in extension board" over the Nikkor-M. I was able to use it reasonably well without an extension board. With 305mm of extension (plus 17mm of extra extension because of the difference between the FL and FFD), you can focus a 300mm lens to about 4.4m, and that worked well enough for my needs at the time, but moving to an Ebony with 365mm of bellows made that lens a lot more useful. Add 10mm of extension with the Fuji and you can focus down to about 3.2m. A 20mm board gets you to about 2.5m, etc. All at maximum extension, which you should try out to see if the camera seems unsteady when extended all the way.

1/300 - 1/(305 + 17 + extension board) = 1/minimum focusing distance. For the Nikkor-M, it would be 1/(305 + 10 + extension) etc.

Doremus Scudder
24-Jan-2019, 12:41
I'd go for at least 20mm. Otherwise, you may not be able to focus on closer subjects (e.g., 3-4 feet from the camera). The combination top hat board that Randy mentions would be a great tool; shorter when you don't need it and longer when you do. I see these on the 'Bay pretty regularly.

My own top-hat board for the 300mm Nikkor M on my Wistas is a homemade board about 2.5 inches long. I till can't focus much closer than 3-4 feet or a bit less, but that serves my purposes just fine 99% of the time.

Best,

Doremus

Ed Vatza
24-Jan-2019, 18:59
Appreciate the responses. I will look into top hat alternatives. I do see the combo top hat available on Ebay.

Ed

andrewch59
25-Jan-2019, 07:16
I was wanting to shoot the moon last week with a 590mm lens on my 8x10. I just missed out on infinity focus by a couple of inches, so I made a top hat out of cardboard. A really good outcome which I think I will hang on to. Just an option, and cheap!

Jac@stafford.net
25-Jan-2019, 09:38
My Wista 45DX has a 12" bellows. That translates to 305mm. That's pretty tight if I want to use a 300mm lens.

If you could try a Tele-Xenar 5.5/360mm (https://www.schneideroptics.com/info/vintage_lens_data/large_format_lenses/tele-xenar/data/5,5-360mm.htm) you might find it adequate.

rdeloe
25-Jan-2019, 11:13
If you could try a Tele-Xenar 5.5/360mm (https://www.schneideroptics.com/info/vintage_lens_data/large_format_lenses/tele-xenar/data/5,5-360mm.htm) you might find it adequate.

That lens has a flange focal distance of 214mm. Yikes. On my Wista you could focus as close as 0.75m with one of those. I looked at some pictures of the lens mounted on a Wista/Linhof board, and I'm not even sure it would mount. With that Copal 3 shutter, bits of the shutter and lens might get in the way of the frame assembly on the camera.

Jac@stafford.net
25-Jan-2019, 11:41
With that Copal 3 shutter, bits of the shutter and lens might get in the way of the frame assembly on the camera.

This thread (https://www.largeformatphotography.info/forum/showthread.php?27728-Mounting-Copal-3-on-Wista-Board&p=261375&viewfull=1#post261375) might be helpful. I have the spacer ring. It works.

EdSawyer
25-Jan-2019, 12:03
Tele Xenar can be found in a compound 3 also, which is smaller than copal 3.

I have one of those variable top-hat boards like Randy mentions, it's useful and well made, esp. for the price.

rdeloe
25-Jan-2019, 17:00
Thanks Jac. Is there a question that has not been asked and answered on this forum? I seriously doubt it!

Now, the interesting take-away from that thread Jac pointed me to is that the solution involves moving the lens forward -- like you would with a tophat extension board, which means on a Wista 45VX like mine you're messing up the ability to do axis tilts. With a telephoto lens like the Tele-Xenar 360/5.5, you're doing that already so it doesn't matter. But if you're putting something in a Copal 3 that isn't a telephoto, it's something to keep in mind if you care about axis tilt.



This thread (https://www.largeformatphotography.info/forum/showthread.php?27728-Mounting-Copal-3-on-Wista-Board&p=261375&viewfull=1#post261375) might be helpful. I have the spacer ring. It works.

rdeloe
25-Jan-2019, 17:02
Ed, was that supposed to be "Compur 3"? If so, I see what you mean. I headed over to the auction site and found a nice APO TELE XENAR 400mm in a Compur 3. It's much smaller than the Copal 3.

Performance and durability-wise, the Compur 3 is good?




Tele Xenar can be found in a compound 3 also, which is smaller than copal 3.

I have one of those variable top-hat boards like Randy mentions, it's useful and well made, esp. for the price.