LF Lenses ... what's the difference ? (Tech)

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Tricky69

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Yes
So

the new year is coming up fast :eek:

One of my projects for the next year is to build a large format camera.

Maybe an 8x10"

I can make everything except the lens, so I was wondering what makes a LF lens different to a MF or 35mm ??? :shrug:

I know some modern digital lenses cant project the image onto a full frame sensor - just a crop sensor etc

is it the same for the old ones ???

If I am to buy into a lens "system" with a particular mount, which are cheapish, but still decent quality ? Obviously I could make numerous lens boards with different mounts, so I dont necessarily need to get tied into one mount type.

any advice ... muchly appreciated (y)
 
Hi Tricky,
I recommend spending a few hours on this forum

http://www.largeformatphotography.info/forum/index.php

They certainly know what they are talking about but I can answer a few questions. LF cameras don't have mounts as such but use lensboards with different size holes. Therefore you can use any lens on the camera as long as it covers 8x10 as you have different lens boards with different hole sizes.

Modern 8x10 lenses are normally quite expensive but you can get old second hand lenses very cheap. The one on my 4x5 at the moment covers 5x7 and only cost £20 off ebay. What is your budget?
 
LF lenses are different to 35mm and MF in that they don't come in a particular mount or system. They simply have a smaller bit in the middle which is surrounded by a shutter/aperture mechanism. These then fall into a couple of different sizes, ranging from small for smaller lenses, up to pretty huge for big lenses. There are some lenses that come in random shutters which may well be different sizes, but generally most stuff thats any good you will buy will come in a copal 0, 1 or 2 shutter.

These attach to the lens boards with a screw on (usually) retaining ring, so the lenses are interchangable with any lens board with the correct size hole and it soens't matter if you buy one mounted to the wrong lens board.

Essentially the difference between smaller format lenses and large format lenses is coverage. If you hold a 35mm lens up to the light, and put a black piece of card behind it you can see the projected image, and realise how small it is. LF lenses have to cover at least the film size they are designed to work on, most also offer excess coverage to allow for the movements

When building your camera buy the film holders you want to use first. This means you can make the back fit the holders, you don't want to make a back that doesn't quite fit when you do buy them
 
Thanks both . Usefull info there :)

My budget is as little as possible to start with, as it is purely a learning exercise as to how these things work.

Once I have learned, I will up my budget and make a more refined camera, going off my experience with the 1st. Then I might know enough to chose a lens budget depending on what I might want to shoot.

If I make a 10x8, will I be able to use any size upto that - by putting different fronts and backs on ?
 
It might be best to get a cheap lens off ebay, do you have any experience with shooting LF? Because the learning curve is very very very steep!!

If you make a 10x8 camera you can shoot different films by having a different back or a reducing back. The front can stay the same but it will of course give you a different field of view.
 
never even seen one, let alone used one.

We have a 5x4 one at college apparently, so I will ask if I can scrutinize it and try it out, when we go back next week.
 
raathistle said:
When building your camera buy the film holders you want to use first. This means you can make the back fit the holders, you don't want to make a back that doesn't quite fit when you do buy them
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Can I make the holders ? or are they cheap enough ?
 
10x8 is very big, not the sort of thing you can put in a rucksack. I would strongly recommend starting with 4x5 first. You can get 4x5 holders for about a £10, 10x8 are slightly more rare and cost a bit more.
 
I really wouldn't even try and think about making holders, unless you are very (very!) proficient at woodwork, and have extremely accurate machinery. It's the bit that holds the film so needs to hold the film perfectly flat. 8x10 film holders are a little on the expensive size, but you won't lose any money on it if you buy one and then sell it on.

If you were closer I could show you one of mine so you know what you're letting yourself in for. I think if you've never seen one before in the flesh you might have underestimated the complexity of them. Making belows for example is not an easy thing to do right. You can bodge your way through it, but you will end up with a camera that is hard to use and ultmiately less enjoyable.

One easier possiblity you could try out is to make a box camera. You make a box where one half slides into and out of the other half, mount the lens in one side, and the film holder in the other and you have made a camera. Very simple and cheap, a sort of massive P&S camera
 
just looking at the film holders there ..

what is a dark slide (yes , I know I need to fine a web site to read - I'll look at the link to the forum in a bit. )

do the holdders hold one or multiple sheets ?

can you change film when you are out, or is it a darkroom only thing ?

HAHA ... so much to learn ... I'm going to love it (y)

oh, and yes - I have the skills and equipment for woodwork, so I just need to see one and copy it. I'll be studying the one at college (I'm on a night course)
 
Dark slide is a commonly mistaken name for film holders. The dark slide is the bit that slides in and out of the holder to expose the film to light. They normally hold 2 sheets, one on each side of holder, and have a dark slide for each side.

Film changing is possible in the field. You need a film changing bag, whioch you put everything inside, zip it up, and then put your hands through 2 tubes and work by feel. It's a little hard at first but you soon pick it up.

If there is one I would suggest watching a video of the whole process, reading it is fine but until you get a camera in your hands it doesn't mean anything.

As Liam said above, the learning curve is steep. It is immensly rewarding when you end up with a perfect 5x4 sheet of velvia or similar in your hand though. It beats the smaller formats hands down, and the process of actually making something is very rewarding
 
There's a company that makes a kit form 10x8 or 5x4 camera - it may not be exactly what you want, but have a look at the build instructions for making one - it's actually quite a good way to see the mechanics of how a large format camera can "hang together" There's also a "walkthrough" and video of the build here

(At one point I was thinking about buying one of the kits, and building it initially as a pinhole camera - instead of the front lensboard, just a plain board with a pinhole sheet. I'd then upgrade to a lens-based version as funds allowed. Still may have a go at some point - though it's on the back-burner at the moment, as it'd involve a whole load of extra dosh on scanning kit for the big neg's :shrug:)
 
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I shoot 5x4 on a regular basis.
Really think hard about going 10"x8" as the film is very expensive, difficult to develop yourself and the kit is not very portable.
You will probably just need one lens to start off with, just make sure it has enough coverage for 10'x8', few lenses offer much movement with 10'x8'.

Having said that, wide open, you will produce unique looking images, do your back in and have lots of people stopping to chat to you :)
 
:)
 
If you do decided to build a 4x5 instead I could probably send you an old wooden darkslide and a ground glass...
 
Liam said:
If you do decided to build a 4x5 instead I could probably send you an old wooden darkslide and a ground glass...
Click to expand...

That would be cool :)
I wouldn't need it for long, just to take some measurements and see how it works (y)
 
Liam said:
Check this thread out, its a work of art that camera.

This thread may give you a bit of inspiration as well...
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oh dear :eek:

you really shouldn't have done that :nono:

Wow !!! now I am really hooked :LOL: :love: :bonk: (y)
 
Basically a camera is a box that excludes light, an aparatus to fucus light and a light sensitive bit to record light.

One of my most viewed images was taken with an old photocopier lens with no shutter. Just a hat hung over the lens, take the dark slide out, remove hat and expose for about 3 mins (night shot) and then reverse the process (replace hat, reinsert dark slide).

The discussion on mounts etc is slightly misleading. On MF and 35mm the mount is a defined distance from the film plane. Any lens must be able to focus on that film plane. A lens whose natural focal length is longer than that distance has to go through some optical trickery to get to focus on the film and is known as a telephoto lens.

LF doesn't require that. Instead you extend the bellows to put the lens where you want it. You can therefore use simpler lenses which don't require optical trickery for focus or zoom, and can give better results (and be cheaper).

Shutters tend to be diaphragm rather than focal plane shutters and incorporated in the lens. As they take a certain amount of time to open and close, as they are opening it is the effect of having a much narrower aperture so greater depth of field. This imposes a practical limit on shutter speed at wide apertures.

I have also used the aforementioned photocopier lens with an old Xray imaging shutter gaffer taped on the front. It works just fine.

Welcome to the world of experiment. The one lens type that is hard to get is extreme wideangle. This has to go very near the film so can be liable to vignetting as the light falls off across the image circle, and focus can also be a wee bit problematic.

..d
 
Liam said:
Hi Tricky,
.........

.........

but you can get old second hand lenses very cheap. The one on my 4x5 at the moment covers 5x7 and only cost £20 off ebay. What is your budget?
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Can you (or any one else) point me out a few if you notice any please :)

I have decided to start with 5x4, but I am stuck finding any lenses for that price that are being sold as large format.
 
This guy sometimes has cheap lenses for sale, there doesn't seem to be much available at the moment probs because of the holidays. There are some cheap lenses on this site, like anything you get what you pay for so my £20 lens isn't brilliant but it does the job.
 
ah, so it's not me then ... there just aren't any about at the moment.

I just want something functional, with a half decent image so I can build and test the camera. and start using it !

Thanks for the links, I'll keep an eye on them (y)
 
There are usually loads on ebay, try and get a cheap one with schneideritis or a scratched element if you don't want to spend too much.
Caltar are a good brand to look at, they are rebadged Rodenstock made for Calument, I've got a 210mm and it's perfect.
 
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is there any way of telling what film size the lens is for, as most of the listings / adverts dont say :thinking: :shrug:

some just say 'vintage lens' ???

or do I just have to take a chance, and sell it on if it's not what I want ?
 
I would be careful as some of the lenses might be for 6x9 or smaller, the only way to tell is to hold it up to a window with a black piece of card behind and see how much of it covers.
 
hmmm .... If I can hold it up to the light , that means I've bought it already ! :LOL:

I've noticed some come with shutters and some dont.... is there any particular shutter I should be looking for the lens to come with ?
 
Tricky69 said:
hmmm .... If I can hold it up to the light , that means I've bought it already ! :LOL:

I've noticed some come with shutters and some dont.... is there any particular shutter I should be looking for the lens to come with ?
Click to expand...

One that works at slow speeds :LOL:
 
Tricky69 said:
I've noticed some come with shutters and some dont.... is there any particular shutter I should be looking for the lens to come with ?
Click to expand...

You should really be looking at lenses with shutters -- lenses with Copal 0 or Copal 1 shutters are probably best for 5x4 as Copal 3 shutters are big and heavy. Older lenses are often found with Compur shutters. [Cleaning a sticking shutter costs around £70 so...]

You'll need to get a shutter key (basically a cut metal sheet to tighten the retaining ring on the back of the shutter) to mount shutters/ lenses on lens boards. The boards come in different sizes, so check you're getting boards that are the right size for your camera -- you'll probably end up needing Linhof/ Ebony size boards. The boards will have a central hole sized for the shutter.

...and don't forget to pick up a cable release, something like: http://www.calumetphoto.co.uk/item/BR5012/

You might find this table of common 5x4 lenses useful: http://www.largeformatphotography.info/lenses/LF4x5in.html
 
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Liam said:
If you do decided to build a 4x5 instead I could probably send you an old wooden darkslide and a ground glass...
Click to expand...

Hi Liam. Ive decided to go 5x4 to start off with, so if the offer is still there, I'd like to take you up on it :)

Thanks

Rich
 
Hi Rich, I was bit stupid and forgot that I was going back to Uni. If you can wait till the start of march I can send them your way but all my 5x4 stuff is at home.

Really sorry mate.
 
no worries Liam. I might make a 120 roll back (if that's what they're called ? ) and use the lens if I disassemble a MF folder. and add a 5x4 back later. I might even make it big enough to fit a 10x8 back ???``
 
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Yes, still interested, ta. And thanks for the link ... it looks interesting (y)
 
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