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  1. #11
    Charles Webb's Avatar
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    I have mentioned several time in my posts that this was a respected and common darkroom procedure/practice performed by most everyone in the past.

    Charlie....................

  2. #12
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    This procedure is called 'rectifying' and is used in making maps or mosaics from large quantities of aerial photos from planes that are not always flying straight or level.

    Since it was in widespread use at one time, they made both an enlarger and an easel with this tilt capability built in. Could be that some of them are still available on the 2nd hand market. They were called "rectifying printers" or "rectifying easels".

    If you used the corresponding rectifying camera, built in data was printed on the border of each exposure that gave a printout of the gyroscopic information (deviation) of the plane from its planned course and this could be dialed into the equipment in the lab to auto correct each frame. Without the special camera, you had to guess, and most often it would correct the print but overall the entire map would be pretty useless as scale would not be exact. I have seen a road vanish from one photo pair to another pair through manual correction which distorted the edge at a junction between all 4 frames.

    Of course, this is all now done by sattelite mapping.

    Sorry, but I have nothing more to add other than the name and use.

    PE

  3. #13

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    don't forget when doing something like this, to stop your lens down all the way to increase your dof, otherwise you will be sol.

    -john
    im empty, good luck

  4. #14
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    "I recently switched to shooting with a 4x5 and while I love the perspective and focus control possible with swings and tilts, I hate how heavy the gear is."

    Go to the gym, get some exercise and/or a lighter view camera. You body and doctor will be happy you did when you get to be an old f..t like me and you will be a better photographer for it.

    John Powers
    on a diet and walking every day

  5. #15
    Lee L's Avatar
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    There are used Graflargers around, and Linhof made something similar. These turned view cameras into enlargers, so you had camera movements available in the enlarger.

    Lee

  6. #16

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    I think that unless one has adjustments available on each of the three stages that there reaches a point of image degradation through diffraction. At least that has been my experience. When one tilts the paper easel, then unless you have adjustable lens stage and negative stage you are confined to stopping the enlarging lens down. Enlarging lenses have the same limitations so far as diffraction that taking lenses have.

    I have one enlarger that I would not consider doing this on (Saunders 4550 VCCE)...another (Durst 138S) that would allow me to do it with ease.

  7. #17
    Jim Jones's Avatar
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    Another problem with correcting perspective with an enlarger is the loss of part of the negative's image. A wider angle lens must be used in the original shot if correction is necessary in the darkroom. Also, some dodging may be required to even out print exposure.

    Some enlargers can tilt both negative and lens plane. My old DeJUR Professional 4x5 is one. Little stopping down is required

  8. #18

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    Quote Originally Posted by jp80874
    "I recently switched to shooting with a 4x5 and while I love the perspective and focus control possible with swings and tilts, I hate how heavy the gear is."
    Another option is to get a shift lens for the 35mm for those times where you want a light kit but more flexibility. Kiev makes one that isn't expensive, and I haven't heard any complaints about it yet (not that I've been asking about it, either).
    The Kiev 88: Mamiya's key to success in Ukraine.

    Photography without film is like Macroeconomics without reading goat entrails, and look at the mess that got us into.

  9. #19

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    Tilt the enlarger head one way and the easel the other. Tilt the lens towards the projected intersection in space of the first two. Done with precision, you will be in focus top to bottom.

    Add a rulled grid to the easel to set up the parallel lines and remove it when you add the photopaper.

    The top of the image gets stretched in width to match the bottom so you no longer have converging parallels. It is a different correction than in camera as the image is stretched lengthwise some.

    More exposure is needed in the wide stretched top than the bottom. Figure the difference and do a base exposure for the narrow part and then a slow burn top to bottom to get the extra exposure for the top of the pic.

    Phillips PCS130 enlarger has all the controls to do this perfectly. It is a total pain without the proper enlarger controls. This is mostly why I bought the machine.

  10. #20
    Lopaka's Avatar
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    Charlie and Claire are both right.....it's all a matter of degree. You can get some perspective correction in the darkroom - but if it's waaaaaay out you are not going to make it look right. Like any other aspect of shooting you want to get it as right as you can at the camera, and spend your time in the darkroom wringing the best out of a good negative, not trying to fix poorly shot negs. Back when I worked in the studio, I spent a lot of time trying to make prints that would meet the client's requirements from stuff some of the guys shot very sloppily. It's a PIA!!! And it's never going to be as good as if you put in the effort at the camera.
    Just my tuppence.
    Bob
    "I always take a camera, That way I never have to say 'Gee, look at that - I wish I had a camera'" -Joe Clark, H.B.S.S.

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