Hi everyone! Just thought I'd post to say I managed to make my first 4x5 exposure without breaking anything, forgetting to cock the shutter, etc.! How exciting!!!
Here's a link if ya'll wanna take a look - not for critique; this image is simply for practice. Oh and I didn't do anything as far as sharpening, levels, etc. I think it is a little under exposed but considering I didn't have a clue as to what I was doing, I'm happy.
http://www.dpchallenge.com/image.php?IMAGE_ID=143924
Now I used a 210 lens. If I'd wanted to fill more of the frame would that require something like a 90mm?
Congratulations! If you want the necklace (?) to fill more of the frame then you should use a longer focal length lens - want it twice as big as it appears now, then use twice the focal length , half the focal length for half as big, etc. Also, it might just be the scan but, as Andre suggested, it looks like you could increase the exposure a bit.
Congrats, Ellen. You likely found the almost silent click of the shutter somewhat anticlimactic after the setup and all. ;-)
Assuming you wanted to fill the frame with the necklace, the simple solution is to simply move the camera closer. But, that requires additional bellows extension, and additional exposure compensation. Depending on the bellows draw of your camera, you'd need to play around with the camera position to get the optimal balance between lens-to-subject distance and bellows extension.
Yeah, I'd like to fill the frame with more of the necklace. So when you say use twice the focal length, are you suggesting the same as Ralph, add bellows extension?
And yes, I do need to practice more with the exposure compensation! Which leads to my next question... (please don't laugh at the newbie) My lens is marked (as an example) f16 - two tick marks - then it's f22. I assumed that those tick marks represented f stops in between. Was I wrong?
Oh and Ralph, with the newness of it all nothing regarding LF is anti-climactic :-D I feel like I'm completely starting over but I'm having an awfully good time!
What is usually referred to as the magnification ratio, Ellen, is the ratio of the size of the original object to its size on the film. For a 1:1 ("lifesize") image, you need 2x the focal length of the lens in both bellows extension and lens-to-camera distance. So, with your 210mm lens, that would mean 420mm between the lens and the subject, and 420mm (more or less) of bellows extension. For that degree of magnification, you need to increase exposure by 2 stops. The tick marks between the marked f-stops on the lens are each 1/3 stop. So, if you were using continuous lighting, and your meter said, let's say, 1/8 sec at f/16, you'd want to increase the exposure to 1/2 sec at f/16.
Calumet sells a nifty little exposure compensation tool that consists of a target you place in the scene, and a little ruler that you measure the target on the ground glass. The ruler gives you the needed exposure compensation directly. There's also a formula for calculating it, of course, but the target measurement is often easier.
There is a pdf file that will print out an exposure target. There might even be a link to it on the main part of this site. When you print it out you cut the ruler section out and put the remainder in the subject area. Then use the ruler on the ground glass to measure.
I posted this answer in response to an exposure/bellows extension question on a different forum a few days ago. I'll repeat it here since it seems relevent to the current discussion:
<<At 1:1 magnification you have extended the lens twice its focal length and the extension exposure factor is 4x or 2 stops. At an extension of 1.4 times the focal length you have an exposure factor of 2x or 1 stop.
The extension relationship works like the f/stop sequence so that every time you increase the extension by 1.4 times the focal length, the film will require an additional stop of exposure compensation. (This works with any focal length BTW.) At 2.8 times the focal length your extension factor will be 8x or 3 stops and so on.
The most frequent compensation adjustments typically will occur between infinity and 1:1 magnification. Based on the above relationship and knowing these two limits, it becomes easy to estimate an exposure compensation factor by just eyeballing the extension of the lens.
For example, a 10" lens extended out 14" requires an additional stop. By 20" it requires two stops, so at 16" I'd give it about +1 1/3 stops. At 12" I'd guess about +1/2 stop would be appropriate. This matches pretty well with the extension factor dial in the Kodak Pro Photoguide.>>
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