# What happens when camera overexposes images shot on white seamless?



## 4lane (Dec 10, 2012)

I'd love to get a better explanation for a specific exposure issue I get when shooting product on a white seamless. For example, a shoe. I'm using a 60D with a single B800 alienbee strobe and use a light meter to get proper exposure settings. I have in mind an example where I end up shooting at 5000K, RAW, ISO100, F/11, 1/125. When doing so, the images look spectacular in the viewfinder, everything seems to be great. I know the viewfinder is not 100% accurate, but it's a fairly OK sample of the final image. However, after downloading the images they all have an ugly grey shade on them - they're really terrible.

What is happening here? My thought is that the camera sees so much white in comparison to the small shoe in the photo, that it tries to compensate by underexposing thinking there is too much light. Why it looks good in the viewfinder and not once downloaded I'm not sure. I would expect them to look grey in the viewfinder as well. Can you help me understand what is happening here? 

The goal to get clear, clean images that require minimal post-processing. Especially since you can't really get the true colors back when the image is so grey. Slightly overexposing when taking the picture by going up a stop or two also artificially alters the true product colors. If I'm right in my explanation, I'm wondering if I should recalibrate my camera's idea of what it should over/under expose by using a 18% grey card prior to shooting that session so that it meters properly for the amount of white. Any suggestions??


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## fjrabon (Dec 10, 2012)

do you mean viewfinder or do you mean LCD?  The viewfinder is in no way a representation of what the final image will look like exposure wise.  The viewfinder doesn't take your exposure settings into account whatsoever.  The ugly grey shade simply means your exposure is off.  The lightmeter simply meters to middle grey, so if you don't want middle grey, your light meter settings will be off.  

Greyness doesn't change the color at all.  Maybe you mean something else?  Greyness would only have to do with saturation and exposure, both of which are relatively easy to correct in post.


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## 480sparky (Dec 10, 2012)

If you're shooting in manual mode, the camera isn't doing anything in reaction to the white background.  Keep in mind the image you see in the monitor on the back of the camera is a processed JPEG.

Post a sample photo so we have a better idea of what you're up against.


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## Derrel (Dec 10, 2012)

My guess is that you have the camera's LCD screen set wayyyyy too bright!!! Happens a LOT. This is a very common scenario. WHat you are describing sounds like UNDER-exposure to me...if the white seamless looks dingy and gray, it is UNDER-exposed.

White needs at least + 1.0 stops to look "white-white".

Also...unless you have a flash meter, there is no way the camera's in-camera light meter can read the right flash exposure from the Alien Bee flash...


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## 480sparky (Dec 10, 2012)

Learn to use histrograms to judge exposure.


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## Village Idiot (Dec 11, 2012)

480sparky said:


> Learn to use histrograms to judge exposure.



Don't you judge me!


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## Mike_E (Dec 11, 2012)

Why are you shooting @5000K with an AB?  Do you want it to look cool?

This isn't the main thing but it might add to your problem.

See if you can borrow a flash meter and try again.  Full manual.  @ 5500-5600K (I don't remember what WBs are rated at) unless you do have a reason for shooting @5000K.


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## Bitter Jeweler (Dec 11, 2012)

Just an observation, but....Yet another person finding it difficult to shoot products on white seamless, wanting minimal post work.


:meh:


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## fjrabon (Dec 11, 2012)

also, it sounds like you are shooting in manual?  Your light meter is a stand alone unit (ie not built into the camera)?  There are so many questions to this OP that don't make any sense, and he seems to have abandoned the thread.


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## Robin_Usagani (Dec 11, 2012)

use lightroom and do adjustment brush.  Make the gray area exposed higher and you have all white background.  You can also add a light pointed to the background.


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## Village Idiot (Dec 11, 2012)

OP - Pics or it didn't happen.


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## 4lane (Dec 29, 2012)

I'm using a light meter, which is giving me the settings that I'm working with. I'm also confirming those settings with the histogram, which confirms the exposure to be correct. Images look great in the viewfinder (clean, bright white background, with a product showing accurate colors) and, again, knowing that the viewfinder is not an accurate representation of what the final image may look like, I download the image and get this. The entire image is grey, grey background, with grey hue over the product (this is a fairly bright yellow shoe). 

My thought is that the camera's white balance is set for a scene with some amount of white. But because my scene is almost entirely bright white, the camera is compensating for all the extra light and underexposing. And, if I recalibrate the white balance for the overly white scene i'm shooting, the camera will then not overexpose and will just shoot the image as I see it. Does that sound right?


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## Buckster (Dec 29, 2012)

4lane said:


> I'm using a light meter, which is giving me the settings that I'm working with. I'm also confirming those settings with the histogram, which confirms the exposure to be correct. Images look great in the viewfinder (clean, bright white background, with a product showing accurate colors) and, again, knowing that the viewfinder is not an accurate representation of what the final image may look like, I download the image and get this. The entire image is grey, grey background, with grey hue over the product (this is a fairly bright yellow shoe).
> 
> My thought is that the camera's white balance is set for a scene with some amount of white. But because my scene is almost entirely bright white, the camera is compensating for all the extra light and underexposing. And, if I recalibrate the white balance for the overly white scene i'm shooting, the camera will then not overexpose and will just shoot the image as I see it. Does that sound right?
> 
> View attachment 30323


I'll make a leap here and assume you're using your meter as an incident meter, yes?  The camera shouldn't be "compensating" if you're dialing in your settings in manual, based on what your meter is telling you is correct exposure.  That said, bracket and figure it out, then use that information for future use, rather than beating your head against the wall.


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## 4lane (Dec 29, 2012)

Yes, i'm using the light meter as an incident meter. I've done some bracketing, and I can get the grey out by going up a few stops, but only at the expense of the product's color - it get's overexposed and washed out and difficult to get back the natural color. So, since I'm in manual and the camera isn't compensating in any way, is there a change I should make to WB settings to help correct the grey drab?


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## Buckster (Dec 29, 2012)

If it was color casting problem, I'd say yeah, get your white balance in order with, ironically, a gray card.  But that doesn't seem to be the case here.

It's not making sense to me at all.  Either the scene is correctly exposed, or it's not.  If it is, the white seamless is white and the shoe is then the color and brightness in relation to the white seamless that it's supposed to be.  If it's not correctly exposed, it's either underexposed and the white seamless is gray and the shoe follows suit, or it's overexposed and the white seamless is blown out entirely, the shoe's shadows are disappearing, and the shoe is overexposed.

Only thing left that comes to mind is the color mode or whatever your camera calls it.  Natural, neutral, saturated, etc.  I don't think that should affect a RAW image, but maybe it is transmitting that info to the RAW converter?


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## christop (Dec 29, 2012)

4lane said:


> My thought is that the camera's white balance is set for a scene with some amount of white. But because my scene is almost entirely bright white, the camera is compensating for all the extra light and underexposing. And, if I recalibrate the white balance for the overly white scene i'm shooting, the camera will then not overexpose and will just shoot the image as I see it. Does that sound right?



Maybe I'm just confused, but you seem to be confused with white balance. That has nothing to do with the underexposure. White balance refers to the relative proportions of colors produced by the light source(s), which affects how yellow or blue (or green for many old fluorescent lights) it looks.

To my eyes, the white balance does appear to be slightly low. I believe it should be around 5500K or 5600K for strobes. That could explain why the bright yellow show looks dull (yellow and blue are opposite each other on a color wheel).

The separate issue is exposure. Since you're using a strobe, you need to either increase its power output or open up the lens's aperture by a stop or so.


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## Desi (Dec 29, 2012)

What is your lighting set-up.  Are you using a backdrop light?

Proper lighting for the subject will not be enough to give a white background, you'll need to light this separately. 

I am new to lighting, so I apologize if this is an overly simplistic response.

Desi


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## 4lane (Dec 29, 2012)

My thought is that it is a color casting problem, because my issue is similar to that problem of a blue hue. Maybe the exposure is set properly, but the white balance needs adjusting? I'm shooting at 5000K because of the single flash strobe, but maybe I should set the WB with a neutral reference - which is why i was wondering if i should use a grey card. The only objects in the scene are the yellow shoe and a bright white background. The camera's not liking something in that scenario - I'm thinking it's because the WB setting is not set for this type of scene. Thoughts?


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## Buckster (Dec 29, 2012)

It is slightly cooler on the top left of the image.

What about your post processing?  Are you adjusting levels in post to maximize your histogram?  RAW images tend to be a bit flat and dull SOOC.


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## Desi (Dec 29, 2012)

4lane said:


> because of the single flash strobe



Single strobe....that's the problem


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## Buckster (Dec 29, 2012)

Desi said:


> 4lane said:
> 
> 
> > because of the single flash strobe
> ...


No, it's not.  It's entirely possible to get correct exposure with a single strobe.


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## Desi (Dec 29, 2012)

Buckster said:


> Desi said:
> 
> 
> > 4lane said:
> ...



Then I stand corrected....thanks.

Not meaning to hijack the thread, but he did mention that he overexposes the shoe when he gets a white background.  To me that would seem that the shoe and background require separate lighting.

Anyway.....I'll be quiet now and go for a bike ride....I'm just here to learn.

Good luck with the problem, OP


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## 4lane (Dec 29, 2012)

I have been adjusting levels in post processing to correct the problem. But by correcting the grey, I can't get back the proper product color and vice versa. And certain colored products are effected worse (and some better). That's why I'm trying to get the dull grey removed from the original RAW.


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## 4lane (Dec 29, 2012)

Here's what I'm thinking should be my next steps: Set a custom white balance by taking a picture of the pure white seamless background in the scene, so the camera uses that as 'grey' for future photos, instead of interpreting what grey should be. 

I feel like I just need to tell the camera what is white/grey and maybe my original 5000K setting was telling the camera that the white seamless background was 'less grey' than it ought to, thus underexposing the image casting a grey hue over everything.


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## Mike_E (Dec 29, 2012)

Put the shoe aside and get the background right (plan on getting a flash meter- really ).  If your camera supports it read what it took to get the background to pure white without detail (just there, not over).  This should get you where you want to be, then set your camera to this aperture in manual (shutter speeds don't really count when shooting with strobes/flash- just make sure to keep within your sync speed.  btw the faster you set the shutter speed the less your ambient light will affect your subject so I'd go as high as I could get to keep from contaminating the shot with the ambient) 

Put the shoe back and unless you put the shoe too far away from the background (over exposing it by being too close to the single strobe) you should be good to go.


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## Buckster (Dec 29, 2012)

Thought of something else: Back the light away from the scene more.

Think about this as a mental exercise, not as if these are the actual numbers: If the BG is a foot behind the subject, and the light is a foot from the subject, the BG is twice as far away from the light as the subject is.  The inverse square law would then give you the exact problem you're facing.

By moving the light further back, you force the BG and the subject to be much closer to the same distance from the light, making their exposure values more equal the further back that light is.  Diffuse as necessary to deal with the hardness that will come from that.


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## Sw1tchFX (Dec 29, 2012)

I'm going to assume you want no shadow casted by the product, and the background completely white, as if the product is just floating in white. 

If that's the case, one light isn't going to cut it. You need to light the background and foreground separate. Prop the product up, drop the seamless behind, make big distance between the two, light separately, knock out the props in post, and drop a shadow.


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## 4lane (Dec 29, 2012)

Mike_E said:


> Put the shoe aside and get the background right (plan on getting a flash meter- really ).  If your camera supports it read what it took to get the background to pure white without detail (just there, not over).  This should get you where you want to be, then set your camera to this aperture in manual (shutter speeds don't really count when shooting with strobes/flash- just make sure to keep within your sync speed.  btw the faster you set the shutter speed the less your ambient light will affect your subject so I'd go as high as I could get to keep from contaminating the shot with the ambient)
> 
> Put the shoe back and unless you put the shoe too far away from the background (over exposing it by being too close to the single strobe) you should be good to go.



Thanks I will try that - although, as I've said a few times already, I am using a flash meter and am using the readings verbatim. But maybe by shooting just the background, there will be a change.


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## 4lane (Dec 29, 2012)

Buckster said:


> Thought of something else: Back the light away from the scene more.
> 
> Think about this as a mental exercise, not as if these are the actual numbers: If the BG is a foot behind the subject, and the light is a foot from the subject, the BG is twice as far away from the light as the subject is.  The inverse square law would then give you the exact problem you're facing.
> 
> By moving the light further back, you force the BG and the subject to be much closer to the same distance from the light, making their exposure values more equal the further back that light is.  Diffuse as necessary to deal with the hardness that will come from that.




Thanks, I will experiment with that. In the setup I have now, the background is inches behind the product and the strobe is about 6ft away. But I'll test some different scenarios. Thanks again for your helpful feedback.


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## The_Traveler (Dec 29, 2012)

Have you looked at the picture and read the wb.

It's cold, cold, cold.
Neutralize the background, and this is what you see
No change in exposure


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## 4lane (Dec 29, 2012)

The_Traveler said:


> View attachment 30364Have you looked at the picture and read the wb.
> 
> It's cold, cold, cold.
> Neutralize the background, and this is what you see
> No change in exposure



With some products, it's easy to fix in post, sometimes with just an auto-color adjustment or getting into curves, but depending on the color of the product it's sometimes not as easy. An orange product for example, loses too much of it's natural color during post-production manipulation so i'll looking to better the original RAW photo so each image doesn't require as much hand-touching.


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## The_Traveler (Dec 29, 2012)

4lane said:


> The_Traveler said:
> 
> 
> > Have you looked at the picture and read the wb.
> ...



You are shooting (and over-exposing) so that the light is recorded by the camera as too blue.

So you can adjust the white point and change the center point with a single levels adjustment.
Note how blue the top left corner is.
I have no idea what the real color of the shoe is.
Consider shooting with a color checker


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## Mike_E (Dec 29, 2012)

If you're using PS and a (true) white background go to levels (if you're using jpegs convert to 16 bit first- remember to convert back) then click the right most eyedropper and then click on the background somewhere that is it's whitest.

Or just do a custom WB to start with.


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