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  1. #11

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    Quote Originally Posted by holmburgers View Post
    However, this got me thinking about lens/film resolution. I haven't done a ton of looking into it yet, but it seems like 60 lp/mm is about the limit of resolution.(??) That equals .017mm per line pair.

    Would it be fair to say that it's impossible to reach the resolution of the autochrome starch grains with a typical lens/film combination?
    You're not hoping to reproduce the aliassing problems the Bayer-pattern filters in digi-thingies create, are you?

  2. #12
    Mustafa Umut Sarac's Avatar
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    If you want to force upon your idea , you will have to buy a monitor calibrating spectrophotometer. We were using 15 years ago on mac 100 Mhz , I dont know they are still at the market with a flexible software.
    I guess , you will have many empty areas with monitor photographing , If dots are even still visually visible

  3. #13
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    I like htmlguru's idea... I have an old VHS camcorder, I could see what can be done with that. But actually, you raise a great point about using a computer monitor. That would completely simplify this signal generating portion of it. Just open up Windows paint... voila! That's brilliant.

    However, can anyone comment on my concern about resolving power? At what point will I simply not be able to resolve the pixel elements?

    And no, I'm not hoping to reproduce any aliassing problems, but we'll see what I get !

    I realize a dot matrix printer would work, but I don't have one, and it wasn't my idea, so what do I have to gain?

    I like the idea of painting a wall.... NOT! I'm not that zen! But I did have the idea of planting my backyard with three flowers that produce RGB, and then taking a photo of them for my screen at the peak of bloom. Groovy, eh?

    Thanks for all the input, the slides are on their way to the processor, so I'll report back once I see them.

  4. #14
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    I'm surprised that QG has not suggested that you stop working on this tricolor approach!

    PE

  5. #15
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    Howdy everyone!

    Alright, well I got back my 4x5 slides and I have to say that I'm optimistic, at least for my 1st attempt.

    There is a very pronounced blue cast in the reseau, which is odd since I thought the blue TV "pixels" looked pretty weak on the ground glass. Can anyone comment on typical color shifts that result from reciprocity failure? Lemme guess.... blue?

    To the unaided eye it appears fairly continuous, though I'm sure the aperture-plate pattern from the TV will be apparent in the resultant photograph. Either way, I see red, I see green & I see blue; which in my book spells "additive color synthesis".

    The attachments show the whole slide and then a close up. The scans look pretty miserable; it looks better in person.

    Next step is pin registration (*cough cough*, office hole punch) and reversal processing. I think I might send a couple tests off to dr5 just because my darkroom is in tatters at the moment and I've never done reversal processing. Plus, photo formulary is still down.

    Anyways, just wanted to share an update.
    Attached Thumbnails Attached Thumbnails reseau scan for apug.jpg   reseau closeup for apug.jpg  

  6. #16

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    Quote Originally Posted by Photo Engineer View Post
    I'm surprised that QG has not suggested that you stop working on this tricolor approach!

    PE
    Unlike you, PE, i know when it is appropriate, and when not.

  7. #17

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    It may be a good idea (maybe not?) to see what you can do creating a digital file in PS or similar software, and then have that turned into a slide by a lab.

  8. #18
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    Quote Originally Posted by holmburgers View Post

    There is a very pronounced blue cast in the reseau, which is odd since I thought the blue TV "pixels" looked pretty weak on the ground glass. Can anyone comment on typical color shifts that result from reciprocity failure? Lemme guess.... blue?

    To the unaided eye it appears fairly continuous, though I'm sure the aperture-plate pattern from the TV will be apparent in the resultant photograph. Either way, I see red, I see green & I see blue; which in my book spells "additive color synthesis".


    Holmburgers;

    The result is quite impressive.

    You can expect to see the pattern in the final "color" photograph. There is a formula for calculating the required dot size for any size of reseau - film format match to minimize this and maximize color. It is in "The History of Color Photography" by Friedman.

    At a distance, the slide should look gray if properly exposed. By manipulation in PS, I was able to get a more distinct gray result, which suggests to me underexposure and low contrast. This might help.

    I don't think that the problem is reciprocity.

    PE

  9. #19
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    QG is right , some labs print computer file on to slide film with laser.
    I cant wait the result holmburgers.

  10. #20
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    I shot tape to film transfers for a number of years so perhaps I can help.

    You transparencies look about right. The image of a television is balanced at 6500 degrees K, not 5500K as color film, so it will come out blue. You need to either attach a color balancing filter set to the 4X5 camera, or rebalance the monitor. We balanced the monitor and bought 1200' rolls of 16mm ECN in multiple case lots of the same emulsion. Even with freezing the balance would change slightly as the film aged.

    Also, with the video camera make sure it is in B&W, so you get an even gray scale, and no color shift from the camera electronics
    There is no such thing as taking too much time, because your soul is in that picture. -Ruth Bernhard

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