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Lomo LC-A Instant Back+ Closeup Effect!

Are you a macro maniac or just interested in larger than life shots of your miniatures collection? There's no need for blurry, out of focus pictures anymore as Mandi shows you how to get up close and personal with the new LOMO LC-A Instant Back+!

One thing you might have noticed when dealing with instant backs (be it the Diana or Lomo LC-A one) is the little close-up lens in the package. The instructions say to install it between the lens and the instant film. So far, so good.

But what happens when you forget (by chance or on purpose) to put that in?

Taking a closeup shot using the LOMO LC-A with the regular distance settings would normally result in a blurry image. It can be nice, for sure, but you’re probably looking for a sharp image this time around. This is where physics and the accompanying math come into play. To make a long story short: without a correction lens, you can set the camera to infinity and shoot something from a 9-10cm distance to get a sharp image.

Background:

The Lomo LC-A has a 32mm lens. This number, the so called focal length, says: when you set focus to infinity (before you ask “how can you focus on infinity?”: take 15 billion kilometers, in our case that should be close enough to infinity…) the image taken of the object at this distance is perfectly projected on screen or film situated 32mm behind the lens.

You might have noticed that when setting the focus to a closer range, the lens moves away from film towards the object. The same thing happens when installing the instant back, but instead of moving the lens away from the film, you move the film further away from the lens, therefore you have to get closer to whatever you take a shot of. Now that is a lot of hocus-pocus, but some clever people did the calculations already and left us with a nice formula:

1/S1 + 1/S2 = 1/f

S1 is the distance from the object to the lens, S2 the distance between lens and film and f is the actual focal length of the lens. Measuring the extra distance that the instant back construction causes, we get S2=48mm. f is still 32mm, so:

1/S1 + 1/48 = 1/32 → S1 = 96mm

…which is the perfect distance for an object to project a sharp image (when the Lomo LC-A is set to infinity). If you’re into math, you can also calculate the perfect Instant close-up object distance when the Lomo LC-A is set to 0.8m!

You can also click here for another LOMO LC-A Instant Back+ Tipster by mandi!

written by cruzron

12 comments

  1. cubilas

    cubilas

    or use the wideangle macro tipster!

    about 4 years ago · report as spam
  2. leela_dark

    leela_dark

    cool tipster, I love close-ups!

    about 4 years ago · report as spam
  3. leela_dark

    leela_dark

    ...fantastic gallery!!!

    about 4 years ago · report as spam
  4. rater

    rater

    Ok, that is cool!

    about 4 years ago · report as spam
  5. stouf

    stouf

    Oh Mandi Mandi Mandi... I love these shots !

    about 4 years ago · report as spam
  6. takezzo

    takezzo

    cool, i will give it a try next time

    about 4 years ago · report as spam
  7. rexhibitionist

    rexhibitionist

    Great info, can't wait to try it out.

    about 4 years ago · report as spam
  8. big_penguin

    big_penguin

    Very cool! I soooo have to get the instant back now. Now if someone can come up with a tipster for a darkslide so you can take the instant back off in mid-pack to take the internal lens in or out for different shots (or just take the back off to load a roll).

    Or..... if Lomo can include one in the next version to the back... hint.. hint....hint....

    about 4 years ago · report as spam
  9. luobodingr

    luobodingr

    Wow. This makes this such a compelling purchase. But still. Not cheap when the cost of film is figured into it too... ONe day.

    about 4 years ago · report as spam
  10. vicuna

    vicuna

    Great tipster that opens a lot of new possibilities for instant shooting!! Now i'd like to know the S2 value of the Diana instant back. (is it the same around 48mm ??) ... so I can calculate the focus distance (at infinity) of the different Diana+ lenses! :))

    about 4 years ago · report as spam
  11. mandi

    mandi

    @vicuna: S2 value for Diana instant back is 70mm..

    about 4 years ago · report as spam
  12. beni

    beni

    Really great! l can´t wait to try, you´re a master

    almost 4 years ago · report as spam

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This is the original article written in: English. It is also available in: Italiano, 中文(繁體版), 日本語 & Spanish.