Expo Disc

DeanPhoto

DeanPhoto

Messages
332
Name
Dean Smith
Edit My Images
No
Although I shoot in RAW 100% of the time, I have always had issues with getting the correct white balance whether it be in camera or in post.

With my car photography this is fairly critical as some paints are hard to capture the colour correctly.

So, after reading various reviews I purchased an Expodisc, and I have to say, it is bloomin' marvelous! It takes all of 5 seconds to get perfect white balance at any given time.

If you ever have any issues with white balance, like I had in the past, I thoroughly recommend buying one..

http://www.expoimaging.net/product-overview.php?cat_id=1&keywords=ExpoDisc


I'll take some pics over the weekend to show the differences it can make.

I can't say I've seen many people use them, does anybody here use one?
 
DeanPhoto said:
If you ever have any issues with white balance, like I had in the past, I thoroughly recommend buying one..

I can't say I've seen many people use them, does anybody here use one?
Click to expand...

(y)


md(y)
 
Dogfish_magnet said:
I use the cheap 1.99p fleabay rip off - works a treat
Click to expand...

:plus1: ... though my 77mm cost me £4.99 :p

You only need to get one, that fits the largest lens diameter you have; it can be used with any other lens with smaller diameter.
 
I also use one of the real cheap eBay things and I think that they are good enough to get you in the right ball park. However (mine at least) shows a fair bit of difference at different spots on the image, so I have to make a judgement as to where I pick as neutral.

The thing I really don't like about it is that you have point the disc at the light source rather than the thing you are photographing. This is fine if you are outside, or have a simple light setup, but if you are using strobes/gels and ambient all together then I find a grey card you can put in the picture works more consistently.

From the expodisc instructions
Use the ExpoDisc as an incident tool. Position the
camera so that the light source illuminating your subject passes through the ExpoDisc, usually by standing at
your subject’s position and pointing the camera back towards where you will be taking the shot.
Click to expand...
 
I swear by a WhiBal:

WhiBal%20-%20Before%20And%20After.jpg


I'm sure you can get something generic now which'll do the same thing, but anyway, before I tried these I wouldn't have thought there was anything wrong with the "before" pictures. They're so easy to use - I just leave my camera permanently on overcast, occasionally grab a whibal shot and then sort 'em out in Aperture later.
 
Strolls said:
I swear by a WhiBal:



I'm sure you can get something generic now which'll do the same thing, but anyway, before I tried these I wouldn't have thought there was anything wrong with the "before" pictures. They're so easy to use - I just leave my camera permanently on overcast, occasionally grab a whibal shot and then sort 'em out in Aperture later.
Click to expand...

Ok if you are just shooting a few pics but if its hundreds it can get time consuming. I use the expo disc as it was bought for me and it saves loads and loads of time so thankyou.

Interesting links, looks like the Chinese, clever as always are ripping you all off. Just use the bottom of a margerine tub and cut one out yourselves :LOL::LOL:

stew
 
Strolls said:
I swear by a WhiBal:

I'm sure you can get something generic now which'll do the same thing, but anyway, before I tried these I wouldn't have thought there was anything wrong with the "before" pictures. They're so easy to use - I just leave my camera permanently on overcast, occasionally grab a whibal shot and then sort 'em out in Aperture later.
Click to expand...

artona said:
Ok if you are just shooting a few pics but if its hundreds it can get time consuming. I use the expo disc as it was bought for me and it saves loads and loads of time so thankyou.

Interesting links, looks like the Chinese, clever as always are ripping you all off. Just use the bottom of a margerine tub and cut one out yourselves :LOL::LOL:

stew
Click to expand...

The whibal / grey card is fine even for shooting hundreds of images. You only need to use it on one shoot from the session and then use that as the reference for the rest.

It's the software you use that makes all the difference with a whibal / grey card, using Canon DPP you can alter white balance on a batch of photos all at once take the setting from your reference shot, it's quick and easy. I would think Nikon and the rest have something similar.
 
whiteflyer said:
The whibal / grey card is fine even for shooting hundreds of images. You only need to use it on one shoot from the session and then use that as the reference for the rest.

It's the software you use that makes all the difference with a whibal / grey card, using Canon DPP you can alter white balance on a batch of photos all at once take the setting from your reference shot, it's quick and easy. I would think Nikon and the rest have something similar.
Click to expand...
:plus1:
In Aperture you just select the whibal shot, click on the white balance tool and then click on the grey part of the whibal. Select the "lift" tool then select all the photos taken in the same session, then click the "stamp" button. Immediately you'll see the colour corrected in all the photos.

Worst case is that you took sets of different photos in different lighting conditions - in that case you have to take multiple whibal shots and do this once for each selection of many images. But in these lighting conditions you'd have to use the Expo Disc multiple times, anyway.

IMO the whibal is preferable because you don't have to mess around with fiddly camera menu options during the shoot. You just take a snap & it's done - the "fiddly" part is left to do at your leisure back at your PC later.

It also has the advantage that you can use it, for instance, before or after the shoot. Let's say you know you're going to be shooting this reception, and the Prime Minister is going to walk through the lobby into a hall to do his speech. Lighting conditions are different in the lobby and hall, so you take a whibal shot in each before he arrives, then wait outside on the pavement (taking a whibal shot just as his car comes into view in the distance). You can take photos as he gets out of the car, following him through the lobby & into the hall shooting constantly. He finishes the speech and you follow him outside, taking more photos, but it's now overcast. No problem - you just take a whibal shot when he's driven away & use that as the "overcast reference". The shots taken in each lighting condition can quickly be matched to the corresponding whibal reference in Aperture (or whatever) once you get home. Using an Expo Disc you would have to stop shooting as he walks into the lobby to use the the disk, then again as he walks into the hall and then again when he walks outside again.

I'm not criticising the Expo Disc, just saying that this is why the WhiBal™ works for me. If your camera has multiple custom white balance settings (mine doesn't) then the Expo Disc is probably a lot easier to use in the scenario I described above - it's just a matter of whether you want to change the settings there & then on the camera or later, during processing. Personally, my lack of experience requires all my concentration on exposure & shutter-speed, so it's helpful to have one less setting to select when I'm on location.

The important thing is to understand how white balance affects your photos and having the tools to get the best results - whichever one works for you. IMO either of these tools are better than using a single camera preset (neither sunshine nor overcast will get it right when you're in a forest with light filtering down through a spring canopy of green leaves) or automatic (which may change from shot to shot).

Stroller.
 
I'm being thick but I don't understand how a lens cap can sort the white balance.

I might just buy the cheap ebay one and try it out. I have a nightmare setting the white balance for my shots.
 
It's a translucent lens cap, which blurs the light altogether. The sensor sees only this overall shade of colour and can use that to set custom white balance. You then take the Expo Disk off and shoot normally using this custom white balance.

Have a look on the Expo Disc webite - I'd be surprised if this wasn't explained.

The Expo Disc™ brand disk should be completely colour neutral. The cheap ones off eBay may - theoretically - slightly change the overall colour of the light entering the camera, and therefor give a slightly wrong balance. But in reality this is likely to be negligible - you won't ever be able to tell the difference between a "perfect" one and a cheap one that's "good enough".

If any of this is wrong, please correct me, as I haven't used the Expo Disc myself.
 
Strolls said:
It's a translucent lens cap, which blurs the light altogether. The sensor sees only this overall shade of colour and can use that to set custom white balance. You then take the Expo Disk off and shoot normally using this custom white balance.

Have a look on the Expo Disc webite - I'd be surprised if this wasn't explained.

The Expo Disc™ brand disk should be completely colour neutral. The cheap ones off eBay may - theoretically - slightly change the overall colour of the light entering the camera, and therefor give a slightly wrong balance. But in reality this is likely to be negligible - you won't ever be able to tell the difference between a "perfect" one and a cheap one that's "good enough".

If any of this is wrong, please correct me, as I haven't used the Expo Disc myself.
Click to expand...

Ah right that makes sense.

I did have a very quick look but was running out of time for my lunch so was being a bit lazy I guess.

I’ll order one of those I think. Should save alot of hassle.

Thanks for helping me out with that.
 
Strolls said:
:plus1:
In Aperture you just select the whibal shot, click on the white balance tool and then click on the grey part of the whibal. Select the "lift" tool then select all the photos taken in the same session, then click the "stamp" button. Immediately you'll see the colour corrected in all the photos.

Worst case is that you took sets of different photos in different lighting conditions - in that case you have to take multiple whibal shots and do this once for each selection of many images. But in these lighting conditions you'd have to use the Expo Disc multiple times, anyway.

IMO the whibal is preferable because you don't have to mess around with fiddly camera menu options during the shoot. You just take a snap & it's done - the "fiddly" part is left to do at your leisure back at your PC later.

It also has the advantage that you can use it, for instance, before or after the shoot. Let's say you know you're going to be shooting this reception, and the Prime Minister is going to walk through the lobby into a hall to do his speech. Lighting conditions are different in the lobby and hall, so you take a whibal shot in each before he arrives, then wait outside on the pavement (taking a whibal shot just as his car comes into view in the distance). You can take photos as he gets out of the car, following him through the lobby & into the hall shooting constantly. He finishes the speech and you follow him outside, taking more photos, but it's now overcast. No problem - you just take a whibal shot when he's driven away & use that as the "overcast reference". The shots taken in each lighting condition can quickly be matched to the corresponding whibal reference in Aperture (or whatever) once you get home. Using an Expo Disc you would have to stop shooting as he walks into the lobby to use the the disk, then again as he walks into the hall and then again when he walks outside again.

I'm not criticising the Expo Disc, just saying that this is why the WhiBal™ works for me. If your camera has multiple custom white balance settings (mine doesn't) then the Expo Disc is probably a lot easier to use in the scenario I described above - it's just a matter of whether you want to change the settings there & then on the camera or later, during processing. Personally, my lack of experience requires all my concentration on exposure & shutter-speed, so it's helpful to have one less setting to select when I'm on location.

The important thing is to understand how white balance affects your photos and having the tools to get the best results - whichever one works for you. IMO either of these tools are better than using a single camera preset (neither sunshine nor overcast will get it right when you're in a forest with light filtering down through a spring canopy of green leaves) or automatic (which may change from shot to shot).

Stroller.
Click to expand...

Good explanation :clap:

I use an Expo and find there are times, especially in landscape work, where I simply couldn't get a grey card into the right position for a shot (cliffs & sea come to mind) so an Expo has an advantage there

Other than that though, it's very much a case of each to their own and doing whatever you're happiest with

I know Nikons are easier than Canons in setting the WB as a custom setting as all we do is press a button, whereas it's in a sub-sub-menu on my mate's 5D

But I always had WB as a major headache beforehand, no longer :)

DD
 
So, if you are doing a scenic shot- do you turnaround through 180 degrees with the expodisk attached to measure the light?

It may be a little difficult getting to the main subject of your shot to test the light at where you are shooting from.

Think i will get one of these cheapies & have a play. Someone once said use the top of a Pringles pot but they are now clear.

I presume in the studio you fire a shot at the model with the disk attached to gauge the light?

As always, thanks in advance
 
So, if you are doing a scenic shot- do you turnaround through 180 degrees with the expodisk attached to measure the light?

You (almost) always point the Expo at the light source

It may be a little difficult getting to the main subject of your shot to test the light at where you are shooting from.

Can be - but if you can walk there and walk back it's not a problem, if you're in the same light source you don't need to shoot it from the subject's position though

Think i will get one of these cheapies & have a play. Someone once said use the top of a Pringles pot but they are now clear.

I presume in the studio you fire a shot at the model with the disk attached to gauge the light?

You always point the Expo at the key light source from the subject's position


As always, thanks in advance

Welcome

DD
 
You must log in or register to reply here.
Back
Top