Q&A For Digital Photography
To aid us in making Digital Help as helpful as possible, please be specific in your query and include components, including software, that you use. David says, “Make me guess the problem and I might guess wrong.”—Editor
Saving Space With JPEGs?
Q. I had been using a Canon PowerShot G9 for several years but I gave it to my son and bought a PowerShot S100, pending buying an SLR later this year. The S100 has one less level of compression quality and its highest setting saves the JPEG of the same scene at an average of 4MB to 5MB versus 7MB to 9MB for the G9.
If I open the S100 JPEG in a photo program, then save it at the highest quality, it saves it at 7MB to 9MB.
This raises a question: does the compression level in the camera permanently “throw away” detail, and the higher level save in the photo program “artificially” extrapolate the quality? Or, is a given compression level not permanent, and if I subsequently open the JPEG in a photo program then save it at the program’s highest quality setting, am I truly “retrieving” a truly less-compressed version? One obvious solution here—shoot Raw! I do that sometimes, but for general shooting I still stick with JPEG.
Paul Brenner
Ross, CA
A. The choice of JPEG versus Raw, which was set up years ago when storage capacity space was expensive, could essentially be done away with and no one would lose anything but bad habits. Today there is little need for JPEG lossy compression as it saves little in cost, as storage is a small fraction of the cost of what it was when it was introduced. But bad habits remain even if they serve no practical necessity.
It is not only that compression using JPEG destroys part of the information your camera sensor chip captures, but that it is usually combined with an sRGB color profile that reduces the color captured by the sensor by a third. So the loss is not only measured by comparative file size—you have to add the 30 to 35 percent of color loss that sRGB imposes in addition to compression loss.
Today there are compression methods that are generally available, like JPEG 2000 that is a no loss method, but camera companies stick with the old standard JPEG that reduces information and throws it away, just as sRGB throws away color that can never be restored.
Actually, you might be better off in terms of image quality by keeping your old camera and saving in Raw, and then applying an automated conversion and editing regime, but camera companies want as much incentive as they can get to induce you to spend more for a better camera, and then throw two-thirds of it away by using JPEG/sRGB! It’s not just file size that matters, but the quality of the image information in that file that really matters.
Personally, if I were inclined to spend a few dollars on a digital camera today, I would choose the one with the largest (physical size) sensor at the cheapest price that saves in Raw, and then use the most efficient software to convert and edit the image files. That would get you the best image quality per dollar invested.
X-Rite i1Display Pro
Q. I’m just purchasing a Dell U2410 monitor and need to upgrade my color management hardware and software. (I have an old Pantone Huey for use with my old Sony Trinitron.) What is your current recommendation for a reasonably priced but accurate color management tool? I will be upgrading to the Mac mini you recommend; presently I am still using a G5 tower. Thanks for all your reviews and comments and help—yours is the first column I turn to when I get my issue of Shutterbug.
Ira
via e-mail
A. The LCD display management hardware and software that I recommend as the most accurate, and easiest to use, is the X-Rite i1Display Pro I reported on a few issues back in Shutterbug. Go to the Shutterbug homepage and type in X-Rite i1Display Pro in the Search box to read the review.
I have tested all the current products available that will adjust, calibrate, and profile pro-graphics LCD displays, and the i1Display Pro is definitely the best choice. The list price is a bit stiff, but if you do some online price shopping it sells for considerably less than list price at many reliable outlets.
Mac mini Or Mac Notebook
Q. I just read your Q&A in a recent issue of Shutterbug where you recommend the Mac mini plus a Dell UltraSharp monitor. My question: why do you recommend this combination rather than a Mac notebook plus the Dell monitor? I am a hobbyist photographer and do a lot of heavy Photoshop and Lightroom post-processing
with plug-ins.
Rachel Schneiderman
via e-mail
A. The difference is cost—the Apple MacBook Pro at a base price is $400 more than the cost of the Mac mini I have recommended. Otherwise, in terms of performance there may not be a very noticeable difference. However, I would wonder if the MacBook Pro is as durable, considering the usual life of a laptop compared to a desktop computer.
Affordable Film Scanners
Q. What would you recommend for a computer/film scanner/recording media system? I have both 35mm and 120 film sizes—a lifetime’s worth. I read that the top-of-the-line Plustek scanner for 35mm format is presently the best but they do not, to my knowledge, make a 120 model. At present would the Canon 9000F flat-bed be the next best thing for the 120 film? In their fact sheet, it doesn’t provide the density range! From reading your columns you state that this is very important. Would it be best to have both scanners, or will the Canon or another flat-bed scanner do it all? I do want the best results but have to draw the line at the FlexScan as being too expensive!
David Kure
via e-mail
A. Either the SE or Ai 6 model of the Plustek OpticFilm 7600i are the best 35mm scanners available at consumer prices. Although the Canon CanoScan 9000F with LaserSoft SilverFast software added is the best flat-bed currently at consumer prices for scanning 120 film sizes, it does a good job with 35mm film scanning, but is not comparable to the Plustek 7600i. Currently there is nothing new for scanning coming that may be better than using the Plustek 7600i and the Canon 9000F.
Kodachrome Profiling For Scans
Q. I read your document “Mama Don’t Take My Kodachrome Away,” and have a question regarding purchasing the Kodachrome IT-8 target from LaserSoft or Kodak. If I purchase the Kodak target I have read that I have to download the Q-60 document from Kodak’s website. Adorama is selling the Kodak target for $40. However, LaserSoft is selling their Kodak IT-8 target for $199.99, and it does not come with any software. I have a Plustek OpticFilm 7600i Ai with SilverFast Version 6.6 (which does calibrate targets). If I purchase LaserSoft’s IT-8 will my scanner be able to do the calibration without any additional software? Will I be able to use LaserSoft’s target using a different software program such as VueScan? I am sorry to take up your time, but $199.99 is a lot of money to me. I have been unable to get any technical support from LaserSoft.
Samuel Turner
via e-mail
A. You probably won’t have to buy anything if you have a Plustek OpticFilm 7600i scanner. It may be that the version of SilverFast that came with your scanner already has Kodachrome profile scanning built-in. If you are going to scan Kodachrome slides you have to set the main SilverFast control to which kind of film you are going to scan. There may be three settings to choose from: Positive, Kodachrome, and Negative. That’s right, there is a film setting in SilverFast that automatically shifts the profiling from E-6 to Kodachrome. So you may not need to buy a Kodachrome IT-8 reference slide to obtain Kodachrome profiling for scanning Kodachrome slides. Check it out with your scanner using SilverFast. If you don’t find the Kodachrome film setting in the main general setup but do find the Positive and Negative film type settings, go to www.silverfast.com and see about upgrading your software to a version that has the Kodachrome feature.
By the way, the Kodak IT-8 is an older version of Kodachrome, which I discovered several years ago and purchased. It did not produce a very good profile for scanning my Kodachrome slides. So I contacted LaserSoft Imaging and found SilverFast was working on producing a new set of Kodachrome IT-8 reference slides. As soon as they were available I bought one and have been very pleased with the Kodachrome profile that was produced and I use it now with some of my scanners.
Some Ideas Make Sense, Some Do Not
Q. I am disappointed in your answer regarding UV filtration [“UV or Not to UV”] in the June, 2012, issue of Shutterbug. At best, your answer seems incomplete, but was definitely appropriate for film photography. For digital photography there is another issue at stake other than protection of the front element of the lens. Digital sensors have varying degrees of difficulty in handling light that is not in the visible spectrum. I am not an expert, but as I understand the issue, digital sensors turn such invisible input into noise. Yes, better cameras may have some built-in filtration, but with varying degrees of success. Are you familiar with the B+W UV/IR cut filter (486M)? Granted, it is an expensive filter because it is not the typical absorption filter. It is based upon a more technologically sophisticated set of thin-film micro-coatings that combat flare and ghosting as it disallows IR/UV radiation from entering the lens. I have been using one on my Sony Cyber-shot HX100V, and I am pleased with the results.
J-J Stewart
Geneva, OH
A. I would not agree that the filtration provided over digital camera sensors, even those in inexpensive point-and-shoot cameras, are inadequate. Of course if you believe the advertising claims of a filter manufacturer, that’s another story. But I have serious doubts that a small accessory company can better the research capabilities of Canon, Nikon, or Sony. However, if there is independent third-party research that proves in fact the camera sensor filters are inadequate, I would take your claims more seriously. But you did not provide any such a reference.
Exceptions And Rules
I would like to add to the discussion on protective lens filters (June, 2012, issue) by pointing out that Canon recommends a protective filter for some lenses to complete the dust- and water-resistance capability. This is only relevant when using those lenses with a high-end Canon camera that is weather-sealed.
John Hoffman
via e-mail
I have to say that although I have made my living as a photographer for all too many years, I have never been able to afford the cameras and lenses in the category you are referring to, as the cost is much more than I, or my work, can support. So I do not have the practical experience that would make me immediately aware of that distinction about the lens and camera matches that would justify a filter in front of the lens to seal the system from moisture.
But thanks for letting me know what I have missed. It does not change my basic attitude about glass filters over lenses, however. Usually when I needed filtration I used a bellows lens shade that holds standard 3x3” gel filters; sometimes cheaper and basic gets the job done just fine.
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