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  1. #11
    Steve Smith's Avatar
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    Yes, the +1 is 1000mm.

    If you are using the +2 and +4 together, you have 500mm and 250mm (so you were a factor of 10 out).

    These add together to make a +6 lens. 1/6 = 0.167m or 167mm.


    Steve.
    "People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.

  2. #12

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    Ah sorry yes, that would make more sense! I am having a look at a few other close up filter lenses, currently using a 52mm filter size but I know you can get 88mm filter lenses so if this works I could perhaps look at getting a larger close up filter lens with the same dioptre giving me a lower f number.

    Currently with the 52mm size it would be: 166/52=f3.2
    With an 88mm filter it would be: 166/88=f1.9

    I will look into attempting to mount/free lens the setup already onto a digital camera and see what the image quality is like on it.

    I might still look into getting a single element lens or a cemented doublet lens commercially and mount it, but I will see how this performs first as the imperfections have a certain feel to them.

    Here is an example of some free lensing I did with the +10 lens (there was a gap between the camera body and lens which is why everything shines lol


  3. #13

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    www.surplusshed.com has everything an aspiring lensmaker could ever need - lenses! All sorts and sizes, mostly dirt-cheap.

  4. #14

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    Quote Originally Posted by VPooler View Post
    www.surplusshed.com has everything an aspiring lensmaker could ever need - lenses! All sorts and sizes, mostly dirt-cheap.
    I did see that, however I am not in the US so the shipping would probably cost more than the lens

  5. #15
    Jim Jones's Avatar
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    Quote Originally Posted by m1tch View Post
    . . . With regards to stopping the lens down, I had a Kodak autographic brownie which had the aperture iris in front of the lens rather than behind, I might look into this option as it would allow for the DIY camera to be set up slightly easier than having stops in the middle of the lens.
    The main reason for having the aperture in front of a meniscus lens is for the best overall sharpness with a simple lens. The concave side of the lens faces the aperture. Some later box cameras had a simple meniscus lens in front of the aperture with the concave side of the lens facing the film. This made a more compact camera, but corner sharpness of the image suffered.

  6. #16

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    Quote Originally Posted by m1tch View Post
    I did see that, however I am not in the US so the shipping would probably cost more than the lens
    I live in Estonia and shipping via USPS Priority was some 10-15 dollars for a box full of goodies. Check them out, you might find exactly what you need plus the staff is knowledgeable and you can get valuable information and recommendations from them.

  7. #17

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    Quote Originally Posted by VPooler View Post
    I live in Estonia and shipping via USPS Priority was some 10-15 dollars for a box full of goodies. Check them out, you might find exactly what you need plus the staff is knowledgeable and you can get valuable information and recommendations from them.
    Thanks for that, I will check them out then, due to the low cost of those lenses I would probably get a nice large selection to play with for this current lens and future lenses

  8. #18

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    Quote Originally Posted by m1tch View Post
    Thanks for that, I will check them out then, due to the low cost of those lenses I would probably get a nice large selection to play with for this current lens and future lenses
    Have fun! I plan to make some interesting if not horrible lenses for large format when I have disposable income again. Maybe even my own lomopetzval. Considering that an achromat costs approximately 4$ there, I have nothing to lose but 8$ plus shipping.

  9. #19

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    I just had another play with different dioptre combinations, I have a 135mm Schneider lens so I thought I would have a look at a few wider combos, I know that for 4x5 the 35mm equivilent is 3 times smaller eg a 150mm lens is a 50mm lens equivilent on a 35mm camera.

    I had a go with the +10 lens and added on a +1 to make it an 11 dioptre lens which works out at around 90mm focal distance, so a '30mm' lens, it works ok, fair bit of distortion and I needed to bring the bellows of the speed graphic in a bit as well. I then tried a +14 lens with a +10 and +4, making a 70mm lens or a '23mm' lens eg superwide. I had to bring the bellows all the way home but it would focus, its basically a fisheye lens! Very interesting effect though, would be interested to see that stopped down. That lens would have been a 70mm f1.3 lens which is rather cool, if I had used the 88mm filter it would have been a 70mm f0.8

  10. #20

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    Uuh, sounds cool! Take pictures of what you see on the ground glass! I am intrigued to try this when I get my Graphic. I already have a Box of Many Lenses aka a shoebox full of optical goodies I have scavenged over the years.

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