Q&A - Photobabble 

Information for your inner photo geek

Information for your inner photo geek

  • Q. What photographic paper do you use?

    We always use the highest grade of photo paper available to us in the market. Unfortunately, the volatility in the photographic supplies market in recent years has meant that we have had to shift and reshift between the major industry players for our paper supplies.

    Accordingly, we use either:

    • FujiFilm Crystal Archive photographic paper OR
    • Kodak Royal Digital photographic paper

    as the market dictates.

    Fuji claims that their paper gives improved whiteness, combined with excellent highlight and shadow depth qualities and produces prints that are guaranteed fade resistant for 150 years!

    Kodak claims that their paper is features exceptional levels of detail, natural-looking skin tones, an increased color gamut and state-of-the-art image stability.

    Both of these papers are of the highest calibre and they are a world apart, in terms of quality, longevity and colour fidelity from the inferior sorts of paper used by cheap on-line printers and some national chain stores.

  • Q. What printers do you use?

    Our mini-lab is an Afga D-LAB2+. It works by exposing red, green and blue laser light onto photographic paper and then chemically fixing the image.

    This is a different and superior process to the way inkjet or dye-sublimation based photo-printers work.

  • Q. What resolution do you print at?

    Upto 400 dpi.

  • Q. Is that all? It seems a bit low. My scanner scans at 9,600 dpi. Does that mean my scanner is 24 times better than your printer?

    No. You’re comparing apples and oranges. Or, more illustratively, Kettles and Walruses.

    Current photo print technology does not normally permit resolutions over 400 dpi.

    At 400 dpi, each printed dot is only 63.5 microns (or 0.0635mm) round. This is really small. By comparison, the average human hair is about 100-180 microns thick. Furthermore, if you think about it, each dot must be fixed and stable at that size: because if the dot started out at 63.5 microns in diameter when applied to the paper and then bled i.e. expanded by 10%, every 11th dot would be “lost” because of the bleed.

    Your scanner, by contrast, doesn’t really work in dpi, at all. It works in ppi (pixels per inch) and the “9,600 dpi” figure your talking abour represents a claim for interpolated resolution. The word interpolate means to estimate intermediate values occurring between two known values. It’s a pretty nebulous concept. However, and crucially, interpolation is neither a useful nor appropriate measure for gray-scale or colour image reproduction e.g. the scanning of black and white or colour photographs. Claims for interpolated resolution, however vague, are therefore irrelevant and not a reliable measure of how “good” or “bad” a scanner is.

  • Q. Do you colour calibrate your equipment?


    We calibrate our mini-lab, several times a day on the main paper sizes, and at least once a day on all paper sizes.

  • Q. I have no idea what an ICC profile is. What should I do?

    Ignore the next few questions and answers. There’s no need to worry about the small stuff. This is very small stuff.

  • Q. Do you have ICC profiles for your printers?

    Yes, we do.

  • Q. Can I download them for soft proofing my images?

    No, sorry.

    It’s not that we don’t want to be helpful, it’s just that providing a profile as a download isn’t actually very helpful.

    Our printer profiles, like anyone elses, are dependent on our printers’ operating parameters and our current working paper stock. These can and do change from time to time. If we made a profile available as a download, and it changes, there’s a significant risk that user’s could be soft proofing with the “wrong” profile. Using the “wrong” profile will produce a worse result, than not using a profile at all.

  • Q. What happens profile-wise, when I open an image in a ICC profile aware application, like Photoshop, and subsequently print it?

    Unsurprisingly, it depends on your colour management settings and the application.

    However, typically and taking Photoshop as our example, when an image is opened, Photoshop will:

    1. Read any source profile previously embedded in the image file by the camera or the application (the “input” profile). AND
    2. Convert the image into the current RGB Working Space, which is a calibrated RGB space, such as sRGB or AdobeRGB1998. (the “working” profile) THEN
    3. On display, the image will be converted from the Working Space to the colour space of the monitor, using the display profile (if any). OR
    4. On printing, the image will be converted from the Working Space to the colour space of the printer, using the printer profile (if any).

    Both the display and the print profiles could be considered “output” profiles.

  • Q. Do you support embedded ICC profiles?

    We try to, but we can’t guarantee it.

    In a perfect world, our workflow would always respect embedded colour profiles. However, an embedded colour profile presupposes a reference colour space and we cannot know or change what the reference for the embedded colour profile is/was. The reference could have been the current version of the ICC profile specification (version 4), the most widely used (version 2) or something else a bit more random.

    Accordingly, the only sensible approach in our print workflow is to print the colour information present in the file. This, inevitably, assumes that the reference color space used by any embedded (i.e. working) colour profile matches the reference used by our printer’s profile.

    It should also be remembered that:

    “It is not the device that needs to have ICC compatibility - but the application software driving it. Thus, for example, a printer or monitor alone cannot easily support ICC profiles - unless it has a software application driving it that allows you to define the input profile to go with it so that the transformation can be calculated.”

    Extracted from the ICC website.

    So, the question of supporting an embedded profile, is really only relevant to the software application, when an image is being edited. This is because what you’re supporting is the use of profile embedded in the image, as the “working” profile.

    In other words, if your image is profiled by you and we just print, it’ll (probably) be fine…

  • Q. So, which working profile would you prefer me to use?


    Why not keep it simple? sRGB, start to finish, just works.

  • Q. I don’t understand the difference between RGB and CMYK images. What should I do?

    Ignore the next few questions and answers. There’s no need to worry about the small stuff. This is very small stuff.

  • Q. Do you prefer RGB or CMYK images?

    RGB is the right choice for people who take photographs with a camera. CMYK is the right choice for people who use a robot forklifts to move 60 gallon drums of ink around their magazine printing factory.

    Don’t get confused between:

    1. an image’s colour mode and
    2. the physical method by which the image is printed.

    The colour mode of your image, either RGB or CMYK, affects the colour gamut of the image itself; it does not determine the method which a printer uses to render it.

    An RGB image can be printed by a CMYK printer and vice-versa, perfectly well.

    We print RGB images.

  • Q. Oh. Erm. I’ve saved my file as CMYK image in my photo editing software. Is this a problem?

    Not, really. But we’d recommend that you back it up as a CMYK image and then re-save it as an RGB image.

  • Q. Why shouldn’t I save my file as a CMYK image?

    Because, what you see on screen will differ from your print.

    When you select a colour mode for an image, you permanently change the colour values in the image.

    For example, when you convert colour modes from CMYK to RGB mode, color values in the CMYK gamut that fall outside the RGB gamut are adjusted to fall within the RGB gamut. Consequently, a CMYK image is intrinsically different from its RGB counterpart and this can give rise to discrepancies between your CYMK image and your (converted to RGB) print.

    However, most of the time, this discrepancy is so small as to be irrelevant.

    If you’re really worried about this, and are prepared to incur the tiny cost of a test print, we can print a 6x4 from your original file and you can proof it, just like in the good old days.

  • Q. My camera/photo editing software can save 16-bit colour images, this will produce better quality prints than 8-bit, won’t it?


    The output from 16-bit colour is not qualitatively different from 8-bit colour. An image that contains 16 bits of data per colour channel does not intrinsically contain any more resolution, or anymore colour information, than an image that contains 8 bits of data per colour channel. This measure is, potentially, most significant from a data throughput point of view.

    Or to put it another way, it might help your computer go a bit quicker or process your images better, but it won’t affect the quality of your prints.

    It’s the old Apple Pie analogy.

    Imagine: You have 2 apple pies. You cut one into 6 slices. You cut the other into 12 slices. Each pie is the same size, is made of the same stuff, has the same number of calories and tastes identical, regardless of how big its individual slices are. The only difference is that you can eat 6 slice pie, twice as fast, if you’ve got mouth a big enough to consume an entire slice in one go.

    A 16 bit pie has slices twice as big as an 8 bit pie.

    8-bit colour is, by and large, good enough.

  • Q. Why is 8-bit colour good enough?

    The vast majority of point and shoot cameras, only store 8-bit colour data. The vast majority of printers, only print 8-bit colour data.

    Posh DSLR’s can usually capture 12-bit data, but they do so, to ensure there is still a sufficient amount of colour information is available, even after in-camera corrections for the saturation or contrast take place, to fill the 8-bit data.

    During post production, there are times you might want to work in 16-bit, to ensure complicated and subtle colour information is not otherwise lost (in the sea of other corrections taking place) and most commonly this would be when working with complex gradients. However, using 16 bit data:

    • Takes longer
    • Needs more memory and
    • Creates larger files

    So, even this use, is something which you’d probably want to avoid, unless the particular image and its edits demand it.

  • Q. Can you process my *.raw images?

    We could, but why would you want us to?

    A *.raw image (or any other similar “digital negative” type of file format) is intended to allow photographers to access all of the data available to camera at the time of the shot, for post production. It isn’t intended to be a format for printing and shouldn’t be used as such.

    “Digital negative” file formats like *.raw (as the name implies) are raw, in that, very little in-camera processing is done on the image. For the vast majority of photos, the in-camera processing which is otherwise absent from the *.raw image, is vital to the final print. So, a *.raw image will probably require more post production work (and cost more) than it’s equivalent *.jpg.

  • Q. Ok, so if I want Berkhamsted Imaging to do my post production work, you’ll be better off, if I give you the *.raw files, then?

    Almost certainly not.

    The benefit of shooting *.raw files (and the reason why they are so highly regarded by Pro/Semi-Pro’s) is that *.raw files contain data, which would otherwise be lost, when the data is processed in-camera and saved as a *.jpg.

    Your camera will, one would hope, make a pretty good job of things like white balance, contrast and colour saturation.

    In post production, all of these things are, at best, educated guesses and often, merely, artistic choices. These guesses/choices are the provenance of the photographer, not the printer. Interestingly, and I use the phrase quite wrongly, one of the things that you’d like to be able to change from a *.raw file, post production is an incorrect ISO setting… but you can’t. So, even a *.raw file, doesn’t grant you absolute control.

    Also, it’s a lot easier for people to explain what they want us to acheive, post production, if they start from a *.jpg file that has been processed in camera; than one that requires a whole bunch of other processing, just to reach this point first.

  • Q. But *.raw files, have unsullied data in them, they must be better, surely?

    Again, the benefit of shooting *.raw files is that *.raw files contain data, which would otherwise be lost, when the data is processed in-camera. However, the thing about this data, is that unprocessed data is not necessarily useful data. Data is only worthwhile, if it is useful in the final print.

    The simplest way to look at this is to draw an analogy with data cropped from a digital image. Once the decision has been taken to crop data from an image, the data in the part of the image that has been cropped out is irrelevant. The same argument can be advanced for the data of the *.raw file, which is present, but not used for the final print.

    Once the decision has been made about how to process the data, whether that be taken in-camera or in post-production, the original form that data took is irrelevant.

    This is why “digital negative” is not really an accurate metaphor. A negative is produced after a film is processed. Film can be processed well or it can be processed badly. The quality of the processing will influence the quality of the negative (and ultimately the print). If you’re striving for a tradition film metaphor, *.raw file is more like an unprocessed film… but this is a harder sell for the suits in marketing.

    Any digital file format, whether *.raw, *.jpg or *.whateveryoufeellike is only data. The question is how close is that data to what I want in my final print?

  • Q. But I know that *.jpg is a “lossy” file format and uses compression, I don’t want my images to be compressed and I really, really don’t want to lose any detail by saving them in a lossy format, do I?

    When raw camera image data is saved as a *.jpg file, it first goes through Bayer interpolation, is then modified by in-camera settings such as white balance, saturation, sharpness, contrast etc, and then finally it is saved to the *.jpg file format.

    However, the misconception is that the jpg file format throws away huge amounts of data, which is present in the *.raw file. Whilst some data may be lost, particularly in extreme highlights or dark shadows, jpg files can save a significant amount of space and lose very little quality.

  • Q. So you’re saying “Digital negative” file formats are pointless and useless, then?


    But, unless you’re a serious photographer/digital artist who wants as complete a control as possible over the entire image production process and are prepared to do a lot of post-production work yourself before creating a final print image, they’re mostly irrelevant.

  • Q. I am a serious digital artist who wants as complete a control as possible over the entire image production process and I am prepared to do a lot of post-production work myself before creating a final print image. Surely, I should be getting you to process my *.raw files?

    This brings us full circle.

    If you shoot *.raw files, then, at some point, you’ll have to then you’ll have to convert them into an alternative format to do the post production work.

    …and if you’ve actually done the post production work, i.e. processed the *.raw files, then why not just save your final print images, as *.TIFs or *.JPGs and send us those?

  • Q. I am professional photographer. Can you help me?

    We love Pros. We produce prints for a number of well respected, professional photographers. Printing pro work is always a pleasure.

    We offer services specifically for the professional and we can help you make more profit, by doing your printing, data production etc for you. We can also help you offer your customer’s additional services. Come into the shop, for a chat.