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I would like to ask for some inputs on how I can achieve similar low-key results for a fish: a fish

Current setup: Setup

  1. Small aquarium 30 x 15 x 15 cms (LBH)
  2. The sides and the back of the aquarium are covered by a black muslin cloth.
  3. The LED no longer has cardboard roll on it. I was using this to cut reflections, but it really reduced my working space. The LED helps me focus and provides continuous light.

Question: How do I implement the inverse square law here given the small space? I don't understand how to bring the flash closer to the fish than to the background.

Thank you for reading the complete post.

Goal:

  1. Perfectly and FULLY illuminated subject with no part lost to shadows.
  2. Pitch-black background.
HelloWorld
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    Just a suggestion: Light the fish from the top (or bottom) through the water and don't use an on-camera flash (to avoid glare/reflections from the glass). The area where the camera is positioned should be completely dark. – Era Apr 28 '16 at 18:02
  • Yes, thanks! I'm following those basics. Just wondering how many external flashes I would need. I find my best lighting comes from placing the ext. behind the fish, towards the camera. It register the colors this way, without being too harsh. – HelloWorld Apr 28 '16 at 18:29
  • If you already have images, why don't you post them? Please do so and specify what you want to improve. – null Apr 28 '16 at 19:37
  • Sorry I don't have low-key images at present. The pictured image is what I desire to achieve, that should help you, I presume. – HelloWorld Apr 28 '16 at 21:48
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    Can you share some results that you achieve with your current setup? – null Nov 20 '16 at 12:29
  • Really could use some example images of your progress using the already mentioned suggestions. – dpollitt Nov 20 '16 at 19:47
  • Okay, noted. I will dig through my old images, it is likely to have been rejected and deleted. Or, I can try again and post by Tuesday latest. – HelloWorld Nov 20 '16 at 20:01
  • Something that has helped me with fish is a rubber lens hood to get up against the glass – Raystafarian Nov 25 '16 at 11:32

6 Answers6

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Ok, let us separate this into 2 parts.

I. The inverse square law.

In this case is the relationship between your light and your first object (1) versus the light and the background (2). The background, not the rear glass of the fish tank.

But this would apply in the case you are actually illuminating the background with the same light, which in this case you are not doing.

So the basic idea is that you should put a black cloth away from the fish tank.

Top view:

enter image description here

II. Basic light and fish tank setup

I would first try to use only a vegetal paper on the top of the fish tank (A) and a piece of aluminum foil on the bottom (B). Actually, I think some spill on the sides can work to reduce the shadows. Try putting some white boards on the sides (C).

Lateral and top view:

enter image description here

enter image description here

Unwanted reflections or stains?

If you see some unwanted reflections I would prepare a special softbox with a grid:

Take your flash and put some distance from a sheet of vegetal paper (D) and prepare a cardboard rectangle painted in black on the inside (E).

This way you will have a soft diffused light but with a protection of some extra spill but it is important that the protection is after the diffuser.

You basically want to protect the front and the black glass, mainly to avoid illuminating some stains on the glass (F).

enter image description here

enter image description here

Put the camera away from any light so you do not reflect it on the glass.

If you see the reflection of the fish on the rear glass you could try inclining the fish tank a bit so the reflection moves away.

A grid is normally this: https://www.google.com/search?q=softbox+grid, In this case, is just simply a box of cardboard, similar to what you used on your led. The difference is that the grid goes after a diffuser.

Rafael
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  • Thank you very much! I would like some clarification please:
    1. What is the yellow polygon in the 1st diagram?
    2. I shoot with a light source, any recommendations on it's placement?
    3. What do you mean by softbox with a 'grid'?
    4. I will try white reflectors on the side however, knowing fish I'm not sure how that will work. as they become transparent without a contrasting background.

    Again, I am very very thankful!

    – HelloWorld Nov 23 '16 at 23:53
  • Your light source. The flash. 2) Yes. See the second diagram. Above the fish tank with a difusser paper on top of the tank. 3) Read more carefully the instructions. I will try to make a 3D model but I do not promess to do it very fast. (If someone wants to clarify, feel free to edit the post)
  • – Rafael Nov 24 '16 at 03:28
  • @Rafael- I don't think I made it clear.
    1. I understand the position of the flash. However when I click pictures I have a 'LED lamp' illuminating the fish. Where do I place my LED lamp to minimize shadows? I can experiment on this myself, but I would appreciate your experience.

    2. I still don't understand what you mean by 'grid' so I would appreciate your 3d model, thank you!

    – HelloWorld Nov 24 '16 at 15:46
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    The power of the led lamp is insignificant next to the power of the flash... n_n – Rafael Nov 24 '16 at 15:57
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    Just put the led anywhere it does not interfear with the flash and keep your fish iluminated enough so you can focus. – Rafael Nov 24 '16 at 15:59
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    I updated with some rustic 3D images. – Rafael Nov 25 '16 at 07:19