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Wadmalaw
28-Sep-2016, 10:02
Help! I'm new to wet plate photography and am really struggling understanding brass lenses and whether or not they will fit on my 8x10 wet plate camera. I'm looking for a landscape lens but confused by the descriptions I have seen on eBay.

Also, do I have to use a brass lens with a flange or can I use something else like the Nikor ones I have seen on eBay?

Thanks in advance!

Jim Galli
28-Sep-2016, 12:44
It depends (of course) on what you're visualizing. If very soft corners are OK, any achromatic doublet (think edmonds scientific and their ilk) of about 1X the diagonal across the 8X10 plate should do nicely. 12" focal length. cobble it onto a lens board and have at it. If you dislike soft corners, the longer the focus, the bigger the center sharp area will get. And 18" achromatic meniscus doublet makes a nice 8X10 normal lens. If you buy a meniscus doublet somewhere (#2 dioptor on ebay) and cobble it onto a lens board, make a shade painted flat black to extend out past the lens to help with non image forming light hitting the glass. If you wind up with a more sophisticated lens like an early brass petzval, put the front group by itself at the rear, and voila, a landscape lens. So, no you don't have to follow any rules or even spend very much money.

Jac@stafford.net
28-Sep-2016, 13:04
Oi! Jim Galli's post should be cast in steel.
.
I will add that many, many of the 'old brass lenses' are fast compared to the same focal lengths today. Image making with slow emulsions will introduce you to the original challenges. Enjoy!

Wadmalaw
28-Sep-2016, 18:13
Wow thanks so much for the quick responses and great info...I have a lot of studying to do but I think I'm catching on now. Also just realized why I have been struggling so much - they are all in mm of course...woops. I've got a picture of a lens I bought on ebay but having trouble uploading... 180mm that said would fit up to a 10x12. Based on what you're saying I think it should be a nice wide lens for landscapes which is what I wanted....no?

Jim Galli
28-Sep-2016, 19:04
Probably great for film but it will be rediculously slow for wet plate. Wet plate is such a slow asa equivalent that you'll need something with at least an f5.6 maximum aperture (slow for wet plate standards). f4 petzvals were invented so that wet plate photographers could get portraits down into the 1 - 3 second range. Landscape that is static can take more time. Nothing like getting your feet wet in some kind of workshop setting where folks are doing what you're aspiring to do. You can make huge gains in your knowledge base that way.

EdWorkman
28-Sep-2016, 20:17
No excuse for letting mm mess you up.
But here's a lesson really easy and not exact
25mm is one inch
thus normal lens for 8x10 is 300mm- you do the math
Your quote of
"180 mm fits 10x12"
is a whole nother story
Is it really a very sloooooow very wide angle???
I strongly suggest you follow Jim's excellent advice untill you get some basic knowledge about lenses
focal length, normal for a format, wide, long. etc
There is a lot of basic information on this site, probly at the top of this page
And you can have a lot of fun with Jim's advice while you sort the rest out
Jim is very cool

Michael E
28-Sep-2016, 21:29
Brass is a metal alloy, not a lens type. A wide range of vastly different lenses were mounted in brass. Try to find out what lens you need and then worry about the brass.

You could start here: The lenses you have mentioned are either "normal" lenses with a limited angle of coverage. The focal length will determine the format you can use. Or they are wide angle lenses, with a wider angle of view to cover larger formats at shorter focal lengths. Unless you are planning to shoot architecture or tight spaces, they away from wide angles for now, because they are not very fast. If your 180mm really covers 10x12" and not 10x12cm, it probably opens up to f18. Not fast at all. Especially not for wet plate.

I would also suggest you do your research here or at other competent places. Ebay descriptions are just as often fiction as they are free of facts. That the lens is mounted in brass is the only thing I would believe. For the start, stay away from unmarked lenses, unless you really know what you are doing or love surprises. Famous "silver bullet" lenses can be very expensive, bread-and-butter lenses often do the job very satisfactorily. A 300mm f4.5 Zeiss Tessar delivers sharp images edge to edge when stopped down, gives a pleasing bokeh when used wide open, is fast enough for wet plate, doesn't cost much (especially in the late East German rendition), but rarely comes in a shiny brass barrel.

About the lens flange: No, you don't necessarily need one. I usually make my own lens boards out of soft plywood (or mat board for testing), cut the hole with a jig saw and just screw the lens into the soft material. A hot glue gun also works wonders (hot glue can be removed - very important!). Fast lenses are usually heavy, so try your kludge with caution.

Mark Sawyer
29-Sep-2016, 11:05
Help! I'm new to wet plate photography and am really struggling understanding brass lenses and whether or not they will fit on my 8x10 wet plate camera. I'm looking for a landscape lens but confused by the descriptions I have seen on eBay.

Just to get everyone on the same page, there are different uses of the term "landscape lens". On this forum, we generally use the term for the traditional single cell landscape lens, be it the single element Wollaston Landscape Lens, or the cemented achromatic doublets of English or French Landscape Lens. I think the OP simply wants an old brass lens suitable for landscape photography, like the wide angle rectilinear like the one he posted a photo of.

In the larger photography world, any wide angle lens is a "Landscape Lens, any long focal length lens is a "Telephoto Lens" and any lens you use to take a portrait is a "Portrait Lens". But around here, most of us lens nerds know as second nature that all of those definitions are technically wrong.

Jim Noel
29-Sep-2016, 11:38
Jim,
When are you going to slow down long enough to gather all of the notes similar to the one above into a booklet?
Little tidbits like this are very valuable to those of us attempting to learn more about the use of soft focus lenses.
Jim

Jim Galli
29-Sep-2016, 11:51
Jim,
When are you going to slow down long enough to gather all of the notes similar to the one above into a booklet?
Little tidbits like this are very valuable to those of us attempting to learn more about the use of soft focus lenses.
Jim

A fine compliment Jim, thanks, but I'm going in the wrong direction. Antique cars and Bible exposition are taking most of my time these days.

Wadmalaw
29-Sep-2016, 17:06
Thanks for all the help....I've taken a workshop and feel I have a pretty good understanding of the chemical process of it but definitely not lenses---seems I need to do a little vocabulary research as well. I actually don't care what the lens is made of....I'm just interested in shooting landscapes (not necessarily super super wide as I don't live in Big Sky country). I don't care about shooting portraits right now (maybe eventually). I'll keep researching!

Wadmalaw
29-Sep-2016, 17:09
Right on, thanks! Jim seems very cool :)

alex from holland
30-Sep-2016, 02:24
As you will shoot landscapes you don't need fast petzval lenses. Just look for a zeiss jena or a but slower but tack sharp apo ronar lenses. They are rather but but very good.