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DPChallenge Forums >> Tips, Tricks, and Q&A >> Some questions about water splash photo
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12/07/2009 12:57:02 AM · #1
This is my entry in "Polka Dots" challenge.
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I placed a polka dots patten paper behind the glass bottle with water, cast light from left, reflected the light from right with a mirror, then dropped the transparent glass balls into water to make the polka dots reflected on the glass balls. I hope this could be a more sharp and clean image, but I had problems with light and focus.

First, I have only one Nissin DI886 speedlight, and my lighting technique is not good, so it's difficult to cast light on the bottle and background at the same time. As a result, the white in background is not flat. You can see that the right side is darker and not white. I tried to fix it in Photoshop but in vain. How can I solve this problem with one light?

Second, the glass of the bottle is curved and thick, so I can't focus clearly in whole image. Maybe I should use a tank with flat glass? Besides, if I focused on the dots reflected on glass balls, the water is OOF, and vice versa. I tried to use f/22 but can't solve this problem. What should I do?

I always wonder how to shoot neat, clean and sharp photos like Irene's.(especially in a kitchen instead of in a studio!)

Message edited by author 2009-12-12 04:54:58.
12/12/2009 04:45:14 AM · #2
No one replied me quetions. Maybe my English is too bad to make people understand my questions, so I edited some sentences.

Message edited by author 2009-12-12 04:46:18.
12/12/2009 04:53:25 AM · #3
I'm sorry, I've never done this type of shot before, so my answers are completely guesswork.

1. Is it possible to just use a regular light (not a flash) to add some light to the darker parts of the background? You might throw off the color balance, but you should be able to adjust it. (this might be a stupid idea because of the difference in power between regular lights and flash. But since I don't have a flash unit, I using 250 watt bulbs for lack of anything better.)

2. I'm assuming the focus problem is more with the optics of the balls reflecting a pattern from behind. Any physicists out there? Mine's asleep, but I'll ask him in the morning.
12/12/2009 04:53:46 AM · #4
I do not do Water Splash/Water drop images (or at least, I have not been motivated to yet) so in terms of technicals, I cannot comment.

However, I did score this image relatively high, much higher in % terms than where you finished, so the image did appeal to me........
12/12/2009 05:01:21 AM · #5
Originally posted by vawendy:

1. Is it possible to just use a regular light (not a flash) to add some light to the darker parts of the background? You might throw off the color balance, but you should be able to adjust it. (this might be a stupid idea because of the difference in power between regular lights and flash. But since I don't have a flash unit, I using 250 watt bulbs for lack of anything better.)


I tried this way but the regular light is just not bright enough. ~"~

Thanks for Wendy's and Kai's kind responses. :)
12/12/2009 07:33:33 AM · #6
Originally posted by vawendy:


2. I'm assuming the focus problem is more with the optics of the balls reflecting a pattern from behind. Any physicists out there? Mine's asleep, but I'll ask him in the morning.


This is optics. The sphere acts as a lens and the image created (the dots) is actually behind the sphere so that your would need a really large DOF to get both the bubbles of the splash and the image of the dots.

12/12/2009 08:12:45 AM · #7
If you are going to get a white background, sharp focus, and do it with a high shutter speed, you are going to have to have a LOT of light. (Relatively speaking). Use the highest ISO that is clean for you, and the smallest aperture that you can get by with. F22 really should solve the focus problem, but it takes a lot of light to light an F22 photo.

To get the shot that you WANT, you're going to have to have more than one light, seriously. That's just part of the rules of light. You can do a LOT with bounced flash and light modifiers, but you really need a background light and a foreground light, at least.

One way to get that extra light is to use your computer monitor for a background (assuming you have an LCD or something besides a CRT).
12/12/2009 09:10:35 AM · #8
In a shot like this your lighting should be bounced off your background and onto your subject. You may be asking for too much in wanting the background as focused as the subject with these short distances even if you close down your aperture. Having a blurry background can even help in making your subject look sharper.

You mention you would use a tank next time, I presume you used a large round glass or bowl for this shot. Get rid of it. Use a fish tank, I have a 5 gallon (20L) one and it improved my focus problems tremendously. Curved glass distorts light and your focus will suffer. Focus manually on the mid point in the tank, use something that'll stay in place so you can accurately focus. Remember, it's not the speed of your shutter that is freezing the action, it's the speedlight.

Purchasing another speedlight would help too. One on the background and one on your subject with a reflector to one side should give good results too.
12/12/2009 10:31:14 AM · #9
Originally posted by jkn:

Originally posted by vawendy:


2. I'm assuming the focus problem is more with the optics of the balls reflecting a pattern from behind. Any physicists out there? Mine's asleep, but I'll ask him in the morning.


This is optics. The sphere acts as a lens and the image created (the dots) is actually behind the sphere so that your would need a really large DOF to get both the bubbles of the splash and the image of the dots.


A couple links including
an optics discussion and the ray drawing and focal length calculation for a sphere and a far away observer. [Wendy's hubby who couldn't post links from his account.]
12/14/2009 10:48:05 AM · #10
Originally posted by nards656:

One way to get that extra light is to use your computer monitor for a background (assuming you have an LCD or something besides a CRT).


This is an intresting idea. ;)
12/14/2009 10:55:10 AM · #11
Many helpful advices, thanks everyone. :)

The optics discussion really makes me dizzy. lol
12/14/2009 11:17:40 AM · #12
I tried to get a water splash shot for ages, problems include blurring due to slow a shutter speed and the aforementioned lack of focus due to a low and f number. I used a table lamp in the end, and my on board flash, but I changed my settings to manual, and played about with the speed and aperture until I acheived the desired result. Not as good as some but I was pleased to get a shot in good focus at last.

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this was the end result. It was taken at f16 and a shutter speed of 1/200.
12/14/2009 11:23:27 AM · #13
Basically, all the optics discussion is saying is that focusing on the drop and focusing on what you see in it is different. You can bring both into focus by using a small (physically small - f/16, f/22) aperture so that the depth of field is deep... the same way that you can bring the background into focus on a macro shot by stopping down, or make it really blurry by opening the aperture.
12/14/2009 01:36:54 PM · #14
I scanned the thread and it looks like one thing is missing....it is also missing from your description....

....how many shots does it take Irenem to get that PERFECT entry? Read her descriptions....she shoots hundreds upon hundreds of shots to get ONE entry.

Like I said, I'm not sure how many you shot for your entry but if it was less than 250 tries, then you are putting a very big handicap on yourself.

It looks like you have the set-up done correctly and now you just need to shoot until you get what you think the voters will like.

Originally posted by Deen:

This is my entry in "Polka Dots" challenge.
' . substr('//images.dpchallenge.com/images_challenge/1000-1999/1129/120/Copyrighted_Image_Reuse_Prohibited_835948.jpg', strrpos('//images.dpchallenge.com/images_challenge/1000-1999/1129/120/Copyrighted_Image_Reuse_Prohibited_835948.jpg', '/') + 1) . '

I placed a polka dots patten paper behind the glass bottle with water, cast light from left, reflected the light from right with a mirror, then dropped the transparent glass balls into water to make the polka dots reflected on the glass balls. I hope this could be a more sharp and clean image, but I had problems with light and focus.

First, I have only one Nissin DI886 speedlight, and my lighting technique is not good, so it's difficult to cast light on the bottle and background at the same time. As a result, the white in background is not flat. You can see that the right side is darker and not white. I tried to fix it in Photoshop but in vain. How can I solve this problem with one light?

Second, the glass of the bottle is curved and thick, so I can't focus clearly in whole image. Maybe I should use a tank with flat glass? Besides, if I focused on the dots reflected on glass balls, the water is OOF, and vice versa. I tried to use f/22 but can't solve this problem. What should I do?

I always wonder how to shoot neat, clean and sharp photos like Irene's.(especially in a kitchen instead of in a studio!)
12/14/2009 02:54:09 PM · #15
I think ' . substr('//www.dpchallenge.com/images/user_icon/21_F.gif', strrpos('//www.dpchallenge.com/images/user_icon/21_F.gif', '/') + 1) . ' IreneM does that to get the right shape, changing mostly the drops and not really the camera settings or lighting. The discussion is specifically about...
Originally posted by Deen:

problems with light and focus.

I would think ' . substr('//www.dpchallenge.com/images/user_icon/21_N.gif', strrpos('//www.dpchallenge.com/images/user_icon/21_N.gif', '/') + 1) . ' Deen is expecting specific lighting tips/setups as well as specific fixes to focus problems. You can take 1000 shots, but if they're all out of focus or poorly lit, you haven't achieved much. So yes, you should take lots of shots... but let's start with a good setup - a better way to light it (first of all, more light) and smaller aperture to get more DOF. Those are the suggestions so far, and they're pretty specific (monitors, bounced flashes, freezing the action with strobes rather than shutter, and f/22 have all been suggested).
12/14/2009 03:07:49 PM · #16
Irene herself could go set it up for him. If he takes 10 shots and uses the best one, he is doomed.

I'd like to see irene post every shot of her last 3 first place finishes and see what changes are made to settings.

I personally don't think Irene sets up one "setting" with lights and camera settings and then takes 2000 shots. I think she experiments as she goes....changing lighting and settings. This is where the hundreds of shots come in to play. Looking back, I didn't make this clear in my first post.

Originally posted by george917:

I think ' . substr('//www.dpchallenge.com/images/user_icon/21_F.gif', strrpos('//www.dpchallenge.com/images/user_icon/21_F.gif', '/') + 1) . ' IreneM does that to get the right shape, changing mostly the drops and not really the camera settings or lighting. The discussion is specifically about...
Originally posted by Deen:

problems with light and focus.

I would think ' . substr('//www.dpchallenge.com/images/user_icon/21_N.gif', strrpos('//www.dpchallenge.com/images/user_icon/21_N.gif', '/') + 1) . ' Deen is expecting specific lighting tips/setups as well as specific fixes to focus problems. You can take 1000 shots, but if they're all out of focus or poorly lit, you haven't achieved much. So yes, you should take lots of shots... but let's start with a good setup - a better way to light it (first of all, more light) and smaller aperture to get more DOF. Those are the suggestions so far, and they're pretty specific (monitors, bounced flashes, freezing the action with strobes rather than shutter, and f/22 have all been suggested).
12/14/2009 06:22:11 PM · #17
Originally posted by kenskid:

I personally don't think Irene sets up one "setting" with lights and camera settings and then takes 2000 shots. I think she experiments as she goes....changing lighting and settings. This is where the hundreds of shots come in to play. Looking back, I didn't make this clear in my first post.

I'm sure she does, but ' . substr('//www.dpchallenge.com/images/user_icon/21_N.gif', strrpos('//www.dpchallenge.com/images/user_icon/21_N.gif', '/') + 1) . ' Deen is looking for a starting point - basic lighting and suggested camera settings. Once he's got that, he can experiment and find out what moving/modifying each light will do, as well as what camera settings should be changed.
12/14/2009 06:41:53 PM · #18
I'm not sure how thick your backdrop is, but could possibly shoot the flash through it? That would give you backlighting only, but I think it would work since you're working with a clear object. As to sharpness, not sure what you can do.
12/15/2009 02:53:36 AM · #19
Originally posted by kenskid:

....how many shots does it take Irenem to get that PERFECT entry? Read her descriptions....she shoots hundreds upon hundreds of shots to get ONE entry.

Like I said, I'm not sure how many you shot for your entry but if it was less than 250 tries, then you are putting a very big handicap on yourself.



I took about 200 shots in 6 hours. Less than 250, maybe I'm not patient enough. :P
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