Is my LCD Preview Lying to Me?

Matt518

I did some street photography at an event yesterday afternoon. I took a few test shots beforehand on location to ensure my settings were ok, and they looked fine on the LCD. As I went around taking the pictures, I previewed them on the LCD and they looked fine also. When I got home and uploaded them, many of the pictures suffered from some over-exposure, some more than others. I'm not sure why the preview is showing pictures that look well exposed, but the actual pictures are over-exposed.

I have a Nikon D60, and this only happens when I use the 50mm f1/8. It's an older lens and doesn't meter with the body. I've also noticed on occasion when I use the 18-55mm, the exposure meter may show over-exposure, but the picture comes out fine.

Here's an example - one of the worst in the series. It looked fine on the LCD screen. Shot in manual mode at f/5.6, 1/250, ISO 200, WB Auto, jpeg fine. All other settings - exposure comp, etc. set to 0.

pathfinder

Matt ( sorry about the mistake about your name ), my first thought as I look at this image is that it was, basically, shot in sunlight? Is that correct?

If it was shot in sunlight, ISO 200, would suggest an exposure of f16 at 1/200th. This was shot almost 3 stops hotter than that ( f5.6 at 1/250th ) and that would explain the over exposure notwithstanding what you saw on the LCD, or what your meter suggested. If the lighting was not full sunlight then this paragraph is just hogwash of course


I'll be honest, I do check my LCD for composition, and my RBG histogram for exposure, but that is all. I do not evaluate exposure by chimping, not do I evaluate accuracy of focus by chimping either. I find that I need to see the images on a large monitor to really evaluate those things correctly and not because of poor eyesight. Just that an LCD is not adequate for me.

I do not understand how this image could look proper on your camera's LCD and be this over exposed though. I would expect to find blinkies popping up on my LCD with an image fried like this.

I do shoot Canon though...........( for those who are sensitive, that comment is a joke, meant in good humor. Some of my best friends have the misfortune to shoot with Nikon, and I try hard not to hold it against them! )

If they shoot with a D3, I actually envy them, but I'll never admit to that in public.

Matt518

pathfinder wrote:

Jim, my first thought as I look at this image is that it was, basically, shot in sunlight? Is that correct? Why are you calling me Jim? You must be getting that from the quotes in my signature. I doubt Nachtwey would be asking questions such as this. Anyway, the sky was a little overcast is spots (see next response).

If it was shot in sunlight, ISO 200, would suggest an exposure of f16 at 1/200th. This was shot almost 3 stops hotter than that ( f5.6 at 1/250th ) and that would explain the over exposure notwithstanding what you saw on the LCD, or what your meter suggested. If the lighting was not full sunlight then this paragraph is just hogwash of course It was not "full" sunlight; the sky was overcast in spots (i.e. mostly cloudy), with grey clouds, some a little darker.


I'll be honest, I do check my LCD for composition, and my RBG histogram for exposure, but that is all. I do not evaluate exposure by chimping, not do I evaluate accuracy of focus by chimping either. I find that I need to see the images on a large monitor to really evaluate those things correctly and not because of poor eyesight. Just that an LCD is not adequate for me. Not sure what you mean by chimping; there were no primates anywhere in sight. I don't have a light meter, and I didn't use the 18-55 at all on this shoot so I didn't have the benefit of the built in metering system. I just use the LCD as a quick reference because it's there.

I do not understand how this image could look proper on your camera's LCD and be this over exposed though. I would expect to find blinkies popping up on my LCD with an image fried like this. My thoughts aswell, hence my inquiry.

I do shoot Canon though...........( for those who are sensitive, that comment is a joke, meant in good humor. Some of my best friends have the misfortune to shoot with Nikon, and I try hard not to hold it against them! ) Blah Blah Blah

If they shoot with a D3, I actually envy them, but I'll never admit to that in public.

responses in bold above

LoriKTM

I didn't know what "chimping" was either, but Wikipedia to the rescue!

http://en.wikipedia.org/wiki/Chimping


Sorry, I'm no help with your original exposure issue.

Tango

set your mode to "full auto" or whatever that is for Nikon, and use a lens that will meter.

blah blah blah

Matt518

LoriKTM wrote:

I didn't know what "chimping" was either, but Wikipedia to the rescue!

http://en.wikipedia.org/wiki/Chimping


Sorry, I'm no help with your original exposure issue.

Thanks Lori.

Matt518

AaronNelson wrote:

set your mode to "full auto" or whatever that is for Nikon, and use a lens that will meter.

blah blah blah

JPerkins

You do know the d60 has a blown highlights mode when playing back?

Use the up/down arrow keys to switch through the playback modes until you see the word highlight at the bottom. The lcd will flash in areas where you lost detail due to overexposure.

Hope that helps. The LCD does deceive and especially in lighting such as that. It probably looked blown on the lcd but not the easiest to make out with glare.

pathfinder

Matt -

I am sorry I in-advertently responded with the wrong name. My bad.

If the day was overcast, then you do need 3 stops more light than full sunlight, and that would be reasonably close to your stated f5.6, 1/250 at ISO 200.

But you said this is an older, non automatic lens if I understand correctly? Does the aperture automatically stop down when you trigger the shutter or does it stay wide open at f1.8? Is there an external aperture ring?

If the stated exposure was close to correct, and it seems to be, and the image was actually over exposed, this makes me think the aperture did not stop down to the stated aperture when the shutter was pressed.

Some older lenses are manual lenses, and they have to have the aperture closed manually before triggering the shutter and the re-opened manually as well. ( I have a Zeiss 21mm lens like this that I use on my 5D fairly often).

Some older Nikon lenses ( I used to shoot Nikon years ago ) require that the lens aperture ring be rotated all the way to f22 or thereabouts to enable the lens to stop down automatically to the chosen aperture, when the shutter is pressed. Could this ring have been mis-positioned? If the ring is not in the proper position the lens aperture will not be actuated after the shutter is triggered.

I will stand by my statement that you cannot trust exposure to a quick glance at the jpg displayed on your camera's LCD.

The RGB histogram will not lie to you about exposure. If your image is overcooked, you will have have a spike on the right side of your histogram in at least one of the three channels Red, Green or Blue.

About my lame jokes, you need to lighten up just a tad. They're just lame, not mean

Matt518

JPerkins wrote:

You do know the d60 has a blown highlights mode when playing back?

Use the up/down arrow keys to switch through the playback modes until you see the word highlight at the bottom. The lcd will flash in areas where you lost detail due to overexposure. Yes, I do know that. I didn't bother to check as the images seemed ok, and there was alot going on. At the risk of chimping, I should use that feature more often.

Hope that helps. The LCD does deceive and especially in lighting such as that. It probably looked blown on the lcd but not the easiest to make out with glare. That could be possible. They seemed much darker on the screen, which could have just been glare.

Thanks.

Matt518

pathfinder wrote:

Matt -

I am sorry I in-advertently responded with the wrong name. My bad. No problem.

If the day was overcast, then you do need 3 stops more light than full sunlight, and that would be reasonably close to your stated f5.6, 1/250 at ISO 200.

But you said this is an older, non automatic lens if I understand correctly? Does the aperture automatically stop down when you trigger the shutter or does it stay wide open at f1.8? Is there an external aperture ring? It is an older, manual lens. There is an external aperture ring. I'm not sure about it staying at f/1.8. I just set it at f5/6 because it seemed appropriate for the shutter speed and conditions.

If the stated exposure was close to correct, and it seems to be, and the image was actually over exposed, this makes me think the aperture did not stop down to the stated aperture when the shutter was pressed.

Some older lenses are manual lenses, and they have to have the aperture closed manually before triggering the shutter and the re-opened manually as well. ( I have a Zeiss 21mm lens like this that I use on my 5D fairly often). This is a manual lens, but I was unaware of any such procedure.

Some older Nikon lenses ( I used to shoot Nikon years ago ) require that the lens aperture ring be rotated all the way to f22 or thereabouts to enable the lens to stop down automatically to the chosen aperture, when the shutter is pressed. Could this ring have been mis-positioned? If the ring is not in the proper position the lens aperture will not be actuated after the shutter is triggered. Interesting. I was not aware of this. It was correctly positioned at f/5.6, but I didn't do anything to "set" the aperture other than turn the ring to f/5.6.

I will stand by my statement that you cannot trust exposure to a quick glance at the jpg displayed on your camera's LCD.

The RGB histogram will not lie to you about exposure. If your image is overcooked, you will have have a spike on the right side of your histogram in at least one of the three channels Red, Green or Blue. Like stated above, that's also a feature I should use more frequently.

About my lame jokes, you need to lighten up just a tad. They're just lame, not mean I was just being sarcastic regarding your joke about Nikon users.

Helpful info. Thanks.

pathfinder

Glad to help, Matt.

I can't seem to find an image of an older Nikkor 50mm f1.8 with an external aperture ring

I think this link in Wiki about the Nikon F mount may be pertinent for you, or other Nikon shooters may help you out.

Matt518

I researched this site before I purchased the lens - mine is the 50mm f/1.8E. It seems pretty detailed. http://www.nikonians.org/nikon/slr-lens.html

I've been playing around with the lens, and there is apparently no specific sequence of events required to adjust aperture other than just adjusting the aperture ring. I'm going on the premise that I had the aperture a few stops high and the glare and/or ambient light was making the images on the LCD appear to be properly exposed. My testing has shown both overexposed images on the LCD as well as properly exposed images when stopped down.

ziggy53

Matt,

The combination of in-camera histogram and "blinkies" should get you very close to a proper exposure. Experience with the camera will also help. As you are learning, the LCD preview alone can be misleading.

I suggest that using a non-coupled lens on the Nikon D60 will be frustrating as you get no exposure help from the camera. I do believe that the D200 and D300 allow metering with a manual focus lens.

Matt518

Thanks Ziggy. The truth is I've ran into this problem before. I took some photos of my nephew; the LCD preview looked fine. There was a brick wall behind him - you could see the details and texture of the bricks, however once uploaded the entire background was washed out. You couldn't even see the brick wall.

I understand what everyone is saying about not using the preview alone, that it can be misleading, but to me this seems to be too significant of a difference to be normal.

I've intentionally taken both under and over exposed pictures, and the results are shown on the LCD preview, so I'm at a loss as to why certain images seem fine, yet there's such a drastic difference off camera. It's as if the LCD sometimes functions fine and other times it doesn't.

ziggy53

Matt518 wrote:

Thanks Ziggy. The truth is I've ran into this problem before. I took some photos of my nephew; the LCD preview looked fine. There was a brick wall behind him - you could see the details and texture of the bricks, however once uploaded the entire background was washed out. You couldn't even see the brick wall.

I understand what everyone is saying about not using the preview alone, that it can be misleading, but to me this seems to be too significant of a difference to be normal.

I've intentionally taken both under and over exposed pictures, and the results are shown on the LCD preview, so I'm at a loss as to why certain images seem fine, yet there's such a drastic difference off camera. It's as if the LCD sometimes functions fine and other times it doesn't.

The truth is that the camera's LCD preview/review display is designed as a compositional aid. It is not designed to be used as a calibrated gauge for exposure and contrast/sharpness/etc. There may be gain adjustments to the preview and for sure the LCD is not protected from ambient light, which may have a significant impact on what you see.

Use the LCD for basic feedback and composition and use the histogram(s) and blinkies for exposure. There is no "making sense" of the situation and trying to figure out when you can trust the LCD for exposure and when you cannot. You tried to trust the LCD for exposure and found out that it doesn't work, and it never will work. Go with what does work for judging exposure, the histogram and the blinkies.

Some studio photographers will shoot tethered (or via wifi) to a calibrated computer and display in order to gain more reliable visual information. Even the very best medium format digital backs with an LCD display cannot be trusted for proper exposure assessment. This is not a new phenomenon and you are not alone with your frustration.

Matt518

Will do, Ziggy.

time2smile

If the 50mm is coupled to the D60 it should be lock at the smallest ap. mine locks at F22, then the camera controls the f stops. As you noted this is the E version of lens, it just may be to much of a pain to use reliably. You could get a new 50mm 1.8D for like a hundred. It will not AF but it should meter. Then use yor old 50 for reverse micro shots. Check Ken Rockwell site to review the lens.
I have a D50, the LCD screen has a brightness adjustment in the menu, don't know the D60, but you may want to check if it is turned down. I just also noticed that the angle i look at the LCD makes a big difference in the brightness of the photo.

Tim Kamppinen

I have a 50mm 1.4 AI-S (I think, it's a manual lens anyway) that I used on my D40 before I got a D90 and bought the newer 1.8 D. Obviously I had to manually control shutter speed and aperture and there was no metering and I had to manually focus, but as far as actually taking photos it worked fine. When you turn the aperture ring, whatever you set it at should be the aperture that it stays at. To test this you can take it off the camera and look through the glass. Now turn the ring. You should see the blades opening and closing as you turn it. If you don't, then there's something wrong with the lens and it could be stuck at 1.8 or something like that. If this works ok, then put it on the camera and look through the viewfinder at 1.8. Now turn the ring all the way to f-22. You should be able to see the viewfinder get visibly darker because the blades should still be controlled by the ring when the lens is mounted on the camera. If this works, then I don't think there is anything wrong with the lens. The only reason you would have to turn to 1.8 and then back to your chosen aperture is if you were in a low light situation and needed the larger aperture to nail your focus but wanted a smaller aperture when you took the shot. If you have plenty of light to focus then just pick your aperture and stick with it. No need to adjust.

Obviously this doesn't help with your original question but I just wanted to clear up some of the lens confusion. Are you shooting raw? If so the preview on the LCD will be based on your Jpeg picture settings. These settings are not applied to the raw image however, so it will look different. However, this problem usually results in the raw file looking underexposed, so it might not apply here.

Matt518

I checked and the lens is working fine - adjustment through all aperture settings. We'll chalk this one up to operator error I guess.

dogwood

ziggy53 wrote:

Experience with the camera will also help. As you are learning, the LCD preview alone can be misleading.

It took me a while to learn this too. Never trust the back of your camera until you really know that camera and you have a sense of how it displays images on the LCD. There is invariably a "gut-feeling" in reading the LCD that you learn over time after downloading many, many shoots to a calibrated monitor.

Clients often want to see the back of the camera during a shoot too-- and that's fine with me-- but they don't often understand that the final image may be different than what they see. Checking the histogram and shooting in raw is a good way to go-- but even the histogram can look strange for many subjects.

Basically, what I'm saying is get out there and shoot, shoot, shoot with your camera and learn how it works (including how it tends to display images on the LCD) compared to your final, downloaded results. Over time, you'll get in tune with the camera and learn the LCD isn't always accurate.

P.S. for this same reason I almost NEVER delete images based on the camera LCD display unless it's absolutely obvious (closed eyes, etc). The LCD is just too small to accurately judge.

Scott_Quier

ziggy53 wrote:

Matt,

The combination of in-camera histogram and "blinkies" should get you very close to a proper exposure. Experience with the camera will also help. As you are learning, the LCD preview alone can be misleading.

Ziggy does have a flair for understatement, doesn't he? I have maintained for some time now that the LCD on the camera will not mislead you .... it will flat out lie to you every chance it gets.

with Ziggy's statement that the LCD should be used only for compositional evaluation - are the elements of the photo in the right place. But not for exposure. Canon cameras offer the ability to modify the brightness of the LCD display - something like 5 or 7 stops worth. So, for example if you have it set too dark, then use that as a judge of exposure, your shots will come out way over-exposed.

Right or wrong, I use the LCD only to evaluate for composition and to look for blinkies. And even trusting the LCD image for blinkies can have it's perils (check out this thread some background on that statement).

As suggested by both Ziggy and PF (among others), the histogram is the best tool we have for judging the exposure of an already captured image. If a photographer has the time, a good incident light meter can help one dial in the exposure a lot more accurately - but for many, that's a little over-kill. Get the exposure within 1/2 stop and adjust in post - that's good enough for most of us.