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Photo Forum / Digital Photography / DSLR Cameras / April 2007Expodisc
Hi everyone! I recently came across Expodisc. I went to their website (www.expodisc.com) and discovered that Bill Atkinson describes dust mapping with the ExpoDisc (http://www.expodisc.com/tips/). Can anyone who tried it tell me whether this gadget is indeed practical and worth the expense? Secondly, regarding the claim of mapping dust which can be removed with the help of Lightroom (soon to be added) or Aperture, is this realistic? video at: http://downloads.oreilly.com/digitalmedia/2006/10/19/expodisc_atkinson.m4v Thanks, Marcel >Hi everyone! > [quoted text clipped - 4 lines] >Can anyone who tried it tell me whether this gadget is indeed practical and >worth the expense? You don't need an Expodisc (or something similar) to detect sensor dust. I suspect Bill Atkinson found a new use for an otherwise useful tool. I don't have an Expodisc, but I have a similar device called the Stratos Disk - I picked it up a couple of years ago in a Demo/Clearance bin. I was interested in the Expodisc at the time, but couldn't justify the expense. I think I paid ~$20 for a pawed-over, slightly scratched Stratos. I bought it to set the white balance, and that is how I primarily use it. I also use it as an incident light meter. I suppose it could also be used to find sensor dust, but I've never used it for that. (Sensor dust hasn't been a big problem for me.) Is it worth the expense? For the price I paid ... you bet. But not at full price. I think the Expodisc sells for ~$80 and the Stratos Disk sells for slightly less. I can't justify that price. Not for what looks to me to be little more than a piece of neutral diffusing material. Before I bought my disk I used a piece of opal diffusing glass. It worked fine, but it wasn't an ideal solution for me. It was too big to carry in my pocket and it would break/chip if I dropped it. (And it was what I used as a pigment mixing slab.) It was the best "roll yer own" substitute I tried, and it was inexpensive. I got mine from www.edmundoptics.com, and if you go this route I recommend tetting a piece that's 100mm x 100mm (4in x 4in). Any smaller and it probably won't cover your lens; any larger and it won't fit in a shirt pocket. I also tried using a styrofoam cup, a lid from a plastic container, a piece cut from a plastic milk carton and a piece of plastic diffusing material. The styrofoam cup worked surprisingly well for setting white balance and as an incident light meter. I always thought the color was a little off, and toting around a styrofoam cup wasn't very convenient. I was never pleased with using a lid from a plastic container or a piece cut from a milk carton. I never got around to trying a piece of plastic diffusing material, but it should work fine provided it was close to pure white. >Secondly, regarding the claim of mapping dust which can be removed with the >help of Lightroom (soon to be added) or Aperture, is this realistic? I can't think of any reason it this wouldn't work ... but I haven't tried it. As I mentioned, sensor dust really hasn't been a problem for me. TR >>Hi everyone! >> [quoted text clipped - 62 lines] > > TR Thanks Tom. I looked up the Stratos disk. It looks very much like the Expodisc, but it doesn't have to be screwd on and its 82mm size should accomodate all my lenses. Marcel > Hi everyone! > [quoted text clipped - 13 lines] > > Marcel I have had an expodisc for sometime and use it often. I bought the largest one they had so that I can use it on any lens. No you can't screw it on the front of the lens but holding it in front and setting the cameras white balance manually isn't a two hand job anyways. I have used it on both dSLR and point and shoots as well as a Sony camcorder. If you want to ensure you have proper white balance so you don't have to fool with it post processing it is a great option. It comes with a nice little storage case too. Well worth the $$$ in my opinion. =(8) >> Hi everyone! >> [quoted text clipped - 25 lines] > > =(8) Thank you for a prompt response. Marcel The disc I have is one I bought on Ebay from a Hong Kong dealer. It cost me $5. It's a great tool for white balance. very accurate and saves a lot of guessing later. t also makes detecting dust very easy. If the Chinese version is so cheap, how can the Expo disc people justify their price? Same thing, same functions ten times the price! Sort of reminds me of the Leica Panasonic thing going on right now. same cameras, 60% price difference. Julian > The disc I have is one I bought on Ebay from a Hong Kong dealer. It > cost me $5. > It's a great tool for white balance. very accurate and saves a lot of > guessing later. t also makes detecting dust very easy. Yep, it's nice. The thing is so simple and is nothing more than a fluorescent light diffuser. I made mine from a stepping ring and scrap pebble finish diffuser material. > If the Chinese version is so cheap, how can the Expo disc people > justify their price? Same thing, same functions ten times the price! > Sort of reminds me of the Leica Panasonic thing going on right now. > same cameras, 60% price difference. Well, for starters, there are people that believe all the techno-babble and mumbo jumbo in the advertisements. After all, the Expodisc is "calibrated" for accuracy. Just look at the clueless idiot that was trying to tell me about how "spiky" and how my "transmission" was slipping because of the type of plastic the bottle was made from. These are the types of people that are ripe for the picking by predators like Expodisc. I love stupid people because they have so much expendable income to burn and are more than happy to give it to me. Rita >> The disc I have is one I bought on Ebay from a Hong Kong dealer. It >> cost me $5. [quoted text clipped - 23 lines] > happy > to give it to me. Rita, Above and beyond all the generalities and moralisation, can you share a few facts that would help me? My understanding of white balance is that "it is the process of removing unrealistic colour casts, so that objects which appear white in person are rendered white in your photo. Proper camera white balance has to take into account the "colour temperature" of a light source, which refers to the relative warmth or coolness of white light". If this definition is true, there are ways of guaging it properly beyond a statement of sun or shade. The grey card is one. Expodisc is said to be another. If you do not subscribe to this, then please explain why. A scientific explanation would be fine. Thanks, Marcel Most likely we are talking about something (the expodisc) that is better made and much more accurate. This is why professionals use it and not the $5 one off eBay that is probably close to using a sheet of laser printer paper to set your white balance. BTW (20# held in front of the lens, while the camera is aimed at the light source works pretty well.) =(8) > Most likely we are talking about something (the expodisc) that is > better made and much more accurate. This is why professionals use it > and not the $5 one off eBay that is probably close to using a sheet > of laser printer paper to set your white balance. BTW (20# held in > front of the lens, while the camera is aimed at the light source > works pretty well.) NONSENSE! I'll bet you couldn't pick out the $5 knockoff from the Expodisc in a double-blind test. Rita > I'll bet you couldn't pick out the $5 knockoff from the Expodisc in a > double-blind test. ;) I just ordered one for the fun of it. $8.99 with free shipping from HK. > Most likely we are talking about something (the expodisc) that is better > made and much more accurate. This is why professionals use it and not > the $5 one off eBay that is probably close to using a sheet of laser > printer paper to set your white balance. BTW (20# held in front of the > lens, while the camera is aimed at the light source works pretty well.) What professionals use it? And if any, "why"?  Signature-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. >> Most likely we are talking about something (the expodisc) that is better >> made and much more accurate. This is why professionals use it and not the [quoted text clipped - 3 lines] > > What professionals use it? And if any, "why"? Well for starters 99% of the people at NAPP do. They couldn't say enough good things about it on Photoshop TV. I would guess that the National Association of Photoshop Professionals an organization that not only represents a very large number of professional and not professional Photoshop users, but a very large number of professional photographers and who works very closely with Adobe (in house, with testing and other projects) would know a little something about it. There is a reason pro's pay the big bucks for the Expo disc and not go with the cheap foreign crap. Maybe they care more about the quality of their pictures. =(8) On Wed, 25 Apr 2007 23:25:11 -0700, "=\(8\)" <nospam@nospam.com> wrote: >>> Most likely we are talking about something (the expodisc) that is better >>> made and much more accurate. This is why professionals use it and not the [quoted text clipped - 17 lines] > >=(8) Dear, dear, me. Someone has a different point of view to you and exercises the same right you have to post your point of view and you attack them for it. Let's forget the pros and cons of an expos disk for a moment and look at the concept of a newsgroup. It is for exchange of ideas and information. OK. So your information is that the Expo disk is a wonderful piece of gear. Alan pointed out it's not widely accepted as being the cure all for white balance problems and suggested (rightly too) that a piece of plastic worth a few bucks at most, is significantly over rated and over priced. I've said this myself. And then when someone says there are other, possibly better ways to handle the issue of white balance; You attack all three of us. Maybe at this point you need to declare your pecuniary interests here. No one in their right mind would contradict the view of three other people unless they had an interest in forcing their our viewpoint. So =8, What have you got to gain from making a a.s out of yourself? Julian >>> Most likely we are talking about something (the expodisc) that is >>> better made and much more accurate. This is why professionals use it [quoted text clipped - 6 lines] > > Well for starters 99% of the people at NAPP do. Cite source please. If it's even 9.9% I'll be very surprised. > They couldn't say enough > good things about it on Photoshop TV. I would guess that the National [quoted text clipped - 7 lines] > with the cheap foreign crap. Maybe they care more about the quality of > their pictures. None of them _need_ expodisc to achieve any of it's touted advantages. And since, as David Kilpatrick so astutely pointed out, it is totally useless for RAW shooting and a hell of a lot of pros shoot RAW, so I am sure they are not weasting their time on expodisc. Now please, a little respect in the future with the 99% stats ... my BS detector is a finely tuned and sensitive device and does not like such strong signal. It will take me days to recalibrate it. There is no BSdisc to help me with that! Cheers, Alan Signature-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. > Now please, a little respect in the future with the 99% stats ... my BS > detector is a finely tuned and sensitive device and does not like such > strong signal. It will take me days to recalibrate it. > > There is no BSdisc to help me with that! Didn't you know that 98% of stats cited in NGs are made up on the spur of the moment ... Oh dear, what will that do to your BS detector's calibrations? Signaturecmyk 8< > There is a reason pro's pay the big bucks for the Expo disc and not go > with the cheap foreign crap. Maybe they care more about the quality of > their pictures. > > =(8) If that is so, then perhaps they ought to read this: http://www.rmimaging.com/information/neutral_references.html Robin Meyers has produced an excellent article about using these and other materials as neutral balancers in photography. The Expodisc is considered adequate for general photography, but not for colour accurate photography as it does not produce a flat/uniform spectral response in all lighting conditions. Signature"The only people who are normal are those you barely know" - Anon > Can anyone who tried it tell me whether this gadget is indeed practical and > worth the expense? > Secondly, regarding the claim of mapping dust which can be removed with the > help of Lightroom (soon to be added) or Aperture, is this realistic? Don't waste your money, time or bagspace on Expodisk. It can't help you more with exposure than your camera (the original idea). It can't help you with white balance more than your camera already can (the bail out the bad idea in the digital age). It can't help with spotting sensor dust anymore than pointing the camera into the blue or white sky, or a blank wall, unfocused at f/22 will do. (The continuing bad idea finding a new application that is easily done without the widget). It is simply not only costs money better spent elsewhere, it wastes your time and takes up valuable bag space. Does it do as they claim? Sure. Can you do the same without it? Absolutely. Cheers, Alan Signature-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. >> Can anyone who tried it tell me whether this gadget is indeed >> practical and worth the expense? [quoted text clipped - 19 lines] > Does it do as they claim? Sure. > Can you do the same without it? Absolutely. The best review of the plain vanilla Expodisc I have yet read in some ways! Not 100 per cent though. You can do almost as well with a Pringle tube lid and it's much cheaper. The portrait warm-up Expodisc is pretty good, and gives just the right shift in balance to make great skin tones. Both will, if used right, remove 'green thoughts in a green shade' from your outdoor wedding and portrait shoots on lawns or amongst trees. If they had not sent me two of things free, I probably would never have bothered to test them or write about them (which I have done): http://f2photo.co.uk/articles/view.php?id=54 (registration is needed, but all that registration does is to ensure you get an email when we change the entire site very shortly to a new name, and start converting the articles to HTML). Expodisc is imported in the UK by an old friend of mine in the trade. I do really wonder how they sell any at the price though. The review makes the clumsiness of actually using this item quite clear. David >>> Can anyone who tried it tell me whether this gadget is indeed >>> practical and worth the expense? [quoted text clipped - 24 lines] > ways! Not 100 per cent though. You can do almost as well with a Pringle > tube lid and it's much cheaper. Or a styrofoam coffee cup over the lens used as an incident meter: point the camera at the shooting position from the subject position. Use that meter setting from the shooting position. > The portrait warm-up Expodisc is pretty > good, and gives just the right shift in balance to make great skin [quoted text clipped - 6 lines] > > (registration is needed, THAT WAS TEDIOUS... your comment about pros using RAW and expodisc being esp. not useful for that is especially pertinent and I wish I had thought of that in my blast, above. Good article. Bet it killed the advert. revenue from that source! Cheers, Alan. Signature-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. > your comment about pros using RAW and expodisc being esp. not useful for > that is especially pertinent and I wish I had thought of that in my > blast, above. > > Good article. Bet it killed the advert. revenue from that source! No, in fact we remain on the schedule and in this case the importer is an intelligent guy. He knows that I am unlikely to write a totally negative report - I try to find the reasons why a product exists, and who might benefit. But he also knows I will never just write a meaningless plug for the product. There is an even worse item out there costing 50 per cent more, which works on reflected light. This one was so bad I deliberately left my sample behind in the press room when it was handed out. $200+ for a barely usable plastic assembly you would not pay $10 for if it was a toy. I simply don't even mention such items. Not even the press release. They don't deserve any publicity, even bad publicity. David >> Can anyone who tried it tell me whether this gadget is indeed practical >> and worth the expense? [quoted text clipped - 21 lines] > Cheers, > Alan Ah, this coming from someone that has never used one! =(8) >>> Can anyone who tried it tell me whether this gadget is indeed >>> practical and worth the expense? [quoted text clipped - 20 lines] >> Does it do as they claim? Sure. >> Can you do the same without it? Absolutely. > Ah, this coming from someone that has never used one! This coming from someone who can do everything an expodisc can do with a reasonably good film or digital camera without it using up my budget, time or bag space. I do suggest you read David Kilpatrick's article. It reveals what is good (nothing new) and what is bad (clumsy bit of crap) about the Expodisc. Cheers, Alan Signature-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. > It is simply not only costs money better spent elsewhere, it wastes your > time and takes up valuable bag space. [quoted text clipped - 4 lines] > Cheers, > Alan Alan, I'm interested in what your statement: "Can you do the same without it? Absolutely". How, please? As it is, with my Canon XT, the choices I have are: automatic, sunny, shade... etc. I can also use a grey card ;-( Sometimes, these choices are not too hot. As well, I find that I have colour shifts when I shoot inside (flash or no flash) with different settings. I do have a custom white balance, but the problem is to use it effectively and to be able to set it quickly. The expodisk seemed to be the ideal tool. If there is another cheaper way, yet practical and effective, that would be great. Thanks for taking the trouble to help me. Marcel. >> It is simply not only costs money better spent elsewhere, it wastes your >> time and takes up valuable bag space. [quoted text clipped - 8 lines] >Absolutely". >How, please? If you're just looking for color correction and you have Photoshop, you already have pretty much everything you need. You can perform color correction using Curves: select the White, Black and Gray points, adjust the curve, and you're done. Finding the points takes time, and sometimes the correct point doesn't exist or is hard to find. If you're looking to set a custom white balance and you don't want to spend much/any money on the tool, you can take the sample shot through any number of opaque, whitish items. A styrofoam cup, a pure white sheet of paper, a lid from a Pringles can.... I tried most of the popular tricks and decided they didn't suit my needs. I found the styrofoam cup worked the best, but I needed an XL one to fit my walk-around lens ... and it was a pain in the arse to carry around. It also looks goofy and often becomes the focal point for a conversation that gets boring after the third time. And at one time I had a 18% Gray microfiber cloth that worked well for meter readings and pretty okay for setting the white balance. IIRC, it set me back around $10 or so. Not overly expensive ... but a lot to spend if you just need a microfiber cloth. >As it is, with my Canon XT, the choices I have are: automatic, sunny, >shade... etc. I can also use a grey card ;-( Sometimes, these choices are >not too hot. >As well, I find that I have colour shifts when I shoot inside (flash or no >flash) with different settings. I have a set of WhiBal Cards, and I've found them very convenient alternative to setting a custom white balance, especially if the light changes. I take a reference shot with the card, and then use that to set a Curves layer that I apply to shots in the series. I take another reference shot when the lighting changes. Fast, easy, portable, reasonably priced, and they've held up well. WhiBal is not the only gray scale chart out there. It's just the one I use. www.rawworkflow.com/products/whibal/index.htm >I do have a custom white balance, but the problem is to use it effectively >and to be able to set it quickly. The expodisk seemed to be the ideal tool. >If there is another cheaper way, yet practical and effective, that would be >great. Thanks for taking the trouble to help me. Marcel. I don't regret paying for a Stratos Disk or a set of WhiBal cards. I know I might have saved money by making something, and most likely I would have been very happy. But it's my experience that DIY projects like this end up costing me more than the real product. (I paid nearly $50 for a hotshoe bubble level ... if you add what I spent on my not-so successful DIY attempts to the cost of a real one I picked up for around $25.) YYMV and all that. Me, I look at gadgets like this the same way I look at Bloody Mary mix: I can save money and make my own, or I can save time and buy a jug of readymaade. I have a friend who considers readymade to be a waste of money and borders on alcohol abuse (a waste of good booze). She also thinks Titanic is, like, the greatest movie ever, and so we never discuss tomato juice concoctions and sinking ships. If I want something and I can justify the expense, I'll buy it. And if it works well for me I'll continue to use it. And everyone who goes on about how I wasted money can make their own damned Bloody Marys. TR >>> It is simply not only costs money better spent elsewhere, it wastes your >>> time and takes up valuable bag space. [quoted text clipped - 75 lines] > > TR Thank you Tom for taking the time to explain at length. I get the gist of it. You see, I was hesitating maily because this piece of glass is $114 CAD + Taxes (15%) So I turned around after reading all the answers, and yours really convinced me, and bought an "Expodisk-like" gadget on eBay for $10 CAD. It should do it if what you say you tried works out Cups and lids). I tried 2 layers of Kleenex and it does make some difference ;-) Cheers! Marcel > Thank you Tom for taking the time to explain at length. > I get the gist of it. You see, I was hesitating maily because this [quoted text clipped - 3 lines] > CAD. It should do it if what you say you tried works out Cups and > lids). I tried 2 layers of Kleenex and it does make some difference Tom explained it better than I could. There's nothing mystical or magical behind the Expodisc principle, I just find the mumbo jumbo and sales bullshit beyond ridiculous. The manufacturers of Expodisc are using off the shelf fluorescent light diffuser material that anyone could buy or pull out of the trash. It's their claim that they "calibrate" this piece of plastic that makes me laugh. Here's my homemade Expodisc that I color calibrated. It really works great. <http://www.geocities.com/ritaberk2007/expod.htm> Rita >> Thank you Tom for taking the time to explain at length. >> I get the gist of it. You see, I was hesitating maily because this [quoted text clipped - 20 lines] > > Rita Thanks Rita! That's worth a lot more than philosophy ;-)))) marcel >>It is simply not only costs money better spent elsewhere, it wastes your >>time and takes up valuable bag space. [quoted text clipped - 9 lines] > Absolutely". > How, please? Read your camera manual WB instructions. Look for white things to use as reference in the light you're shooting. Drag along a grey card that has pure white one side. On my camera I can do the "WB" routine, or better yet I simply enter the light temperature in Kelvin. For most light situations that I shoot this I can remember. Best yet: shoot RAW and color correct in Photoshop. Now you're talking. (Take a frame with something white or grey in it if possible). > As it is, with my Canon XT, the choices I have are: automatic, sunny, > shade... etc. I can also use a grey card ;-( Sometimes, these choices are > not too hot. > As well, I find that I have colour shifts when I shoot inside (flash or no > flash) with different settings. Indoor you have to: -overwhlem the tungsten or fluro with flash -or let the tungsten in on the subject for a bit for warmth -use magenta filters against fluro lighting Or shoot RAW and correct in Photoshop RAW import. Just make note of the lighting that you had. > I do have a custom white balance, but the problem is to use it effectively > and to be able to set it quickly. The expodisk seemed to be the ideal tool. > If there is another cheaper way, yet practical and effective, that would be > great. Thanks for taking the trouble to help me. Marcel. Read the article that David Kilpatrick posted. While expodisc might "do" what it says, it imposes gymnastics that are worse (or at least no worst) than simply white-balancing per the camera instructions. A little note: don't be perfectly white balanced. Candle light should look like ... candle light. Sunrise/set light should ... Light on an icy day should look cold (trick: set the color temp down a little as if using tungsten film (or use the "tungsten" setting ... that makes a real "cold" image in the winter, white rooms, etc.). Open shade is one area where a blue cast will come and should be corrected esp. when the subject is a person!). A warming filter or simply raising the color temp pretty high (7000 - 10,000K) will correct that. Cheers, Alan Signature-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm -- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm -- [SI] gallery & rulz: http://www.pbase.com/shootin -- e-meil: Remove FreeLunch. |
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