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Bob Barber
14-Aug-2008, 10:43
Hi,

I'm just getting into large format photography. I have an old press camera that I picked up off ebay, and a Kodak Anastigmat 203mm 7.7 for a lens. I took and developed my first few pictures the other day. Well, none of them were great, mainly because I didn't manage depth of field very well. However, I was excited by the sharpness of the lens and the details that were rendered in the in-focus areas.

I've read that forward tilt will give me more apparent depth of field in certain situations, so I decided to try this. Here's the thing: When I tilt my lens forward, I almost immediately get vignetting. After just a slight tilt, the image circle begins to crawl up across the ground glass. Yes, the image comes beautifully into focus after a time, but now I'm only covering about 2/3 of the film!

I got the Kodak in part because it covers 210mm, and I understood that it would allow me a fair amount of movements on 4x5. My expectations (mainly based on pictures that I have seen of large format cameras in action) were that I could really tilt the lensboard a good 10-20 degrees or more. Well, not on my camera. Not so far...

1) What am I doing wrong, if anything?

2) Would I benefit by buying another lens with even greater coverage?

3) Am I right in assuming that the 210mm lenses with huge image circles (@ 500mm) are WAY too big to use on the kind of camera that I am using now?

I am VERY interested in learning how to do movements. I want to shoot landscapes with foreground objects in focus.

Please give me any tips that you have! Thanks.

aduncanson
14-Aug-2008, 12:59
The Kodak 203 f/7.7 Anastigmatic is a (probably uncoated) predecessor of the well respected 203/7.7 Ektar. It has many fans of its own and should share the Ektar's ability to cover a 5x7 negative. For a great many scenes, only very subtle swings and tilts are needed. This is particularly likely to be the case for most landscapes. I get the impression that you may have been tilting without watching the ground glass and that you went way beyond the optimum tilt. Your Kodak lens should be sufficient for most purposes. On the other hand, if you were trying to focus on a scene set up on a table top, it is possible that an extreme tilt was needed.

It sounds like you need may need a book. "Using the View Camera" by Mr. Steve Simmons who publishes View Camera magazine is frequently recommended for beginners. The following link by Q.-Tuan Luong, founder of this site, goes over the process of focusing using swings and tilts:

http://www.largeformatphotography.info/how-to-focus.html

The principle behind the use of swings and tilts (attributed to and named for a Mr. Scheimpflug) is that the subject plane may be in focus when the subject plane, the lens plane and the film plane all intersect in a line. That is a necessary condition, not a sufficient one - you still have to focus correctly. Consider focusing on a scene with a tree high on a distant hill and a fascinating stone in the foreground. Because you want both the tree and the stone in focus, consider the subject plane to run through both but (because we want to deal with tilt only) would be level in the left-right direction. If your camera is set up square, the subject plane will probably intersect the film plane in a line at, or possibly way below, your feet. In other words 6 to 30 feet below the center of the ground glass. Because the lens is relatively close to the film plane, only a small tilt is required to bring the lens plane to intersect that line.

Think about it, ask questions, read a book, practice and have fun

- Alan

Glenn Thoreson
14-Aug-2008, 13:05
You don't say what camera you're using. The 203 Ektar will cover 5X7 film. I don't know how you're running out of coverage on a 4X5 press camera. 5 of tilt should take care of most situations but my opinion is that you're probably not stopping down far enough. A depth of field chart may help you, also. I use press cameras quite a bit and have never used tilt at all. If you want good depth of field, you're going to find that large format requires smaller apertures than you may be accustomed to in smaller formats and/or with shorter lenses to get good depth. That 203 Ektar should provide everything you need for 4X5 and close to everything for 5X7. It's a very good lens.
Edit: After re-reading your post, I have a couple of thoughts. When I see 203/7.7, I seem to automatically think Ektar. Yours is the early version that came before the Ektar name was thunk up. Still an Excellent lens. If you are going to do table top or similar photography, the press camera is the wrong tool for the job. For that, you need a regular field or, preferably, a monorail view camera. If you are going to do landscapes and portraits, the press camera will serve you very well.

Bob Barber
14-Aug-2008, 14:48
Gentlemen, thank you very much for your answers.

I plan on shooting landscapes for the most part, but this focus issue came up when I was trying to focus within about 10 feet. I had a very narrow depth of field, which is why part of my photo that I wanted to be in focus was out of focus.

It sounds like for starters I need to stop down and try much less tilt than I was using.

I will also pick up the reading material suggested.

Kirk Fry
15-Aug-2008, 00:01
Buy a loupe and use it on the ground glass image. What you see is what you get on the film. Examine things stopped down. A good loupe is probably better than a $1,000 lens in producing sharp pictures. As you age even more important. f32 is also your friend. K

Bill_1856
15-Aug-2008, 00:16
If you're getting vignetting, then you're using 'way too much tilt. You only need a very few degrees, which the 203mm will easily cover.

Bob Barber
15-Aug-2008, 15:09
Guys, what kind of a loupe should I get?

I've got a press camera, so I have that little fold-out hood that keeps me away from the ground glass.

If I held a loupe up to the ground glass, I'd have to look at it from about 4 inches away.

Could I focus that way?

IanG
15-Aug-2008, 16:30
On another forum I posted about my Crown Graphic screen, it's 4 stops dimmer than my Wista, that difference makes it far harder to focus. I've never needed to use a loupe with the Wista, although I do need to use glasses.

A poor screen, and mine on the Graphic is new, makes it very difficult to use the camera.

ian

Bob Barber
15-Aug-2008, 17:19
If I decide to replace the ground glass, what kind should I order, and is it the kind of thing that I can do myself?

Thanks for all of your help.

Bob Barber
16-Aug-2008, 09:01
Well, I took out the ground class and cleaned it up a little bit. It is still not too bright. But the biggest improvement I made was to remove the little paper hood over the ground glass. Now I can see the images and use a magnifying glass to focus. Yes, I will buy a proper loupe soon.

Ernest Purdum
16-Aug-2008, 10:12
Loupe selection is a strongly individual matter. Some people prefer much more magnification than others. Is there any chance you could borrow one? You need one with a focusing adjustment. Before focusing on an image, you focus it on the grain of the groundglass. I like one that is physically long, making it easier to get your eye into position. My favorite has a swivelling base, making it easier to examine the corners, but they aren't easy to find. Fortunately, landscape work with a somewhat long lens is not very demanding where the loupe is concerned. It's the wide angle lenses that make checking corner focus difficult. (They also make groundglass characteristics more important.)

If you can't arrange to try one out, maybe your best bet would be to buy a used one of moderate magnification. If you find after using it awhile that you would like more, or less, magnification, you could probably sell it for somewhere around the price you paid for it and consider any loss involved as cheap rent.