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  • July xx, 2016 at 5:20 pm #994267

    Big watercolour paintings can exist quite catchy to photograph sometimes. The photographic camera has to be of a very adept quality, with very skilful lens that doesn't distort the edges of the prototype, and skillful sensors that can catch accurately the colours of the painting, mounted on a tripod with a good light installation in lodge to avoid shadows or glares on our photographed epitome.

    Merely even all these exist, ( and lets say that someone invested the money to take all these equipment), cameras tin never catch the texture of the newspaper no matter how well the painting is photographed and what are the lighting weather are available.

    And so I concluded up to the conclusion that the best way to have a perfect image of larger paintings ( from A3 size to any size y'all want) is to scan them.
    The advantages are:
    You don't have whatever lens distortion on your picture.
    The colours are better and more accurately detected.
    In HR images is visible the texture of the newspaper

    But how is it possible to scan large paintings, on a A4 scanner?

    Beneath I'll brand a step past step tutorial on how to do this together with full step past step ( with photographs and screenshots ) instruction on how to manipulate and edit your scanned textile in lodge to have a perfect and high definition and resolution paradigm, chromatically accurate that shows also the texture of the paper, ready to utilize for whatsoever purpose you might need it. ( either to bear witness your work on your spider web site or sent high resolution images for joining competitions and such things).

    As this tutorial is going to exist large, and volition need more than three posts to complete please avert to post anything until I write THE END. And so yous can comment or enquire questions freely.

    What you are going to need.

    For the purposes of this tutorial I'chiliad using an Epson Perfection V33 A4 Scanner ( an boilerplate cheap commercial scanner) and GIMP image editor version 2.viii ( free to download and apply manipulation program).

    Other things that you are going to demand is an A4 carton, or an A4 Sketchbook, something at A4 size in guild to put information technology over the part of your painting you scan each time. I observe very convenient to employ ane of my A4 hardbound sketchbooks because they are heavy plenty to keep the paper in place.

    Get too a pencil. (any kind of pencil).

    Make sure that the glass of the scanner is clean ( and check information technology periodically while you are scanning ).

    Scanning

    Allow's outset: Connect the scanner on the pc and identify it on a large steady and flat surface. If your desk is non large plenty place the scanner on the flooring. Yous'll need plenty infinite in social club to exist able to motion and place your large painting freely on the surface of the scanner.

    Then open the lid of the scanner completely flat. On some scanners this can be washed by pulling the lid upward and and then open it completely flat, and in another by removing completely the chapeau.

    And so start the scanner'due south settings programme on the pc and lets proceed with the scanning.

    The main idea is the following.
    Large paintings have (inevitably )to be scanned in parts. So these scanned parts of the painting, have to be assembled in i and unmarried image file.
    The paradigm file must not be that large in size in gild to exist able to be edited later without exceeding the processing ability of the pc and end upwards with a final file that will exist huge and so impossible to manipulate/edit easily.

    So we have to set up the scanner to the best ( optimal ) resolution in gild to do so.
    From my experience the very high resolution for a 56×76 cm painting is 300dpi but if your scanner has good sensors and you are going to use your image for web use you tin can get for 150 dpi without whatever serious lose of quality.

    If you want to scan a larger than 56×76 cm paper, then get for even lower resolution, less than 150 dpi for editing reasons. ( larger painting, more than scanned parts that take to exist smaller in their size).

    I'one thousand going to browse one of my night skies ( that needed either way to rescan it ).

    My painting is 56×76 cm I need it for web employ and to proceed a HR copy just in case so I'll scan at 150 dpi.

    Here are the settings on my scanner's programme.

    Resolution at 150 dpi
    I have gear up it to sequence scanning which means that I don't accept to utilise the mouse in order to start the scanner simply it will scan past pressing its push button. ( very convenient feature for continuous scanning).

    Below is my set on the floor.
    Scanner attached to the pc on the floor, sketchbook, micro fiber cloth to clean the glass and a pencil.

    Place your painting on the edges of the glass of your scanner. This will ensure that your scan parts will be direct and fix for assembling on GIMP.
    It doesn't matter with which edge of the painting you'll start.

    Place the A4 carton or sketchbook ( whatsoever you'll apply) on the top of the painting and exist sure to align it with the scanner's glass.

    Mark with your pencil the border of the A4 function and and then the top edge besides. Your are going to need these marks as guides for scanning the rest of your painting.

    Printing the button to start scanning ( or do it with the mouse)

    After the scanning of the first part is finished, proceed with the role of the painting that is next to it.

    Pay attending now. In order to be easy to assemble these parts in the end, you are going to need a bit of overlap clearance. In other words a piece of the first scanned office existing besides on the second scanned part.
    In lodge to achieve this overlaping between the scanned parts you'll have to place your painting in such a position that the mark that you lot did with the pencil volition exist a bit further within in the scanning surface area.

    Look at the picture below.

    Marshal the edge of the paper with the edge of the glass. This will permit the 2d part to be completely parallel with the first part.

    Identify the A4 sketchbook on this and scan.

    Do the same for the residuum of the parts always taking care to have a fleck of overlap between the scanned parts.

    When yous'll finished the scan sequence on the lower role of your painting, plough the painting upside, align the opposite corner and start scanning with the aforementioned method the upper part of your painting.
    You don't take to intendance for the orientation of the scanned parts you tin can rotate them later on. Take care though to scan at the same direction. From left to right at each side of the painting.
    The upper edges will overlap either fashion because the smaller (56 cm) side of full size watercolour papers is smaller than
    two big sides of the A4 size paper, ( or scanning surface).

    It took me well-nigh 3 minutes to scan the whole painting in eight parts. Mine are in a .png format. I volition convert to .jpg after finishing the editing.

    To be continued. Please don't post annihilation yet

    July 20, 2016 at 5:59 pm #1254785

    Now that we finished with the scanning we tin can proceed with the editing. I'll postal service hither countless screenshots in order to encounter how is done, the bodily editing though it volition not take yous more than 10-fifteen minutes.

    It was impossible to take a screenshot while I was using the carte on GIMP so I'll write what tools I used and what I did each time before each image.

    Become to the folder that your scanned parts are.

    Pay attention now. As I scanned my painting in a landscape position just the final image has to have a portrait orientation, I will assemble the parts in two vertical rows connected in between them.

    So the first four parts of the painting have to be rotated counter clockwise and the rest 4 clockwise.

    Open up the kickoff part with GIMP.

    The signature has to be at the lower left corner.

    Go to menu Image/Transform/Rotate counter-clockwise ( information technology has arrows that shows the direction) Click in that location and GIMP will rotate your image.

    Look beneath


    Remember to do that at each of the first four parts.

    Now that nosotros rotated the first part we have to create a new file on which will do the assembling.

    Go from the menu: File/New

    The size at present of the new file has to exist large enough in order to have plenty of space to place there all the scanned parts.

    I calculated that I need a surface that will be 4000×6000 px.
    ( 8 parts of 1754×1272 px size with enough clearance to move them up and downward. Whatever is not needed volition be cropped at the end).

    My new file is fix for utilize

    I can zoom in and out from the drop down menu on the bottom of the new file.

    Now go to the start function opened right click on it and select

    Edit/Copy

    Movement on the New File ( the blanc one) and with correct click select

    Edit/ Paste

    Here is the first role copied on the new file.

    Select on the tool bar the Move Tool ( meet on the image above were this is).

    Drag with right click the prototype and place it on the lower left corner.

    Open up the adjacent scanned part.
    Rotate ( counter clock wise every bit shown above).

    Pay attention at present we are going to employ the overlap affair.
    As the scanner tends to distort or create shadows on the edges of the scanned image will have to crop the side that will gather. Otherwise will create visible lines that will exist hard to remove in the end.

    Then will accept to ingather the side that volition attach, ( and whatsoever side that volition touch on the rest of our new image).
    In this instance I crop the lower side.

    Come across below. Become to the window that you rotated your second part. Select the Ingather Tool on the tool bar on the side

    So I crop the lower side of the second image.

    After you select which expanse you desire to go out out, right click in the middle of the image and your image volition be ready for copying on the new file.

    Proceed equally previously.
    i/Right click on the prototype, select Edit/ Re-create
    2/Go to the new file right click and select Edit/ Paste.
    3/Select the Move Tool from the tool bar to motility your second office somewhere close to the first part and and then zoom in to accurately bring the two parts together.

    You agree your image with right click and move it until it matches accurately and overlaps the existing get-go part.

    Come across below on my painting the parts that will join by overlapping them. I'll make sure that the dots will exist the 1 over the other. ( endeavour to notice a detail that will guide you lot in gild to do so).

    When you'll detect the right position keep the carte and click:

    Image/Flatten Epitome

    This will fix the position of 2d part in place. If you are not satisfied with the result then press Command Z on your keyboard to become back to the motility pick and right the position.
    You'll take though to apply again the Flatten Image in order to set once again its position.

    Cheque at present below how my two assembled parts await like.
    Not a single line on the edges, absolutely perfectly assembled.

    To be Connected.

    July 20, 2016 at 6:37 pm #1254786

    Two parts assembled till at present.
    We proceed with the same method until will cease the first row.

    Remember to rotate your images and crop the sides that will overlap until y'all stop with this row of iv images.

    Here is the finished offset row.

    And now volition start the adjacent row that will attach it simultaneously on the already existed.

    As I scanned in a landscape orientation and I turned the painting upside down in order to scan the other function of the painting, I'll accept to start my next raw of vertical assembling from the last of the residue four images ( in social club to outset again from the lesser).

    (This doesn't accept to be a rule. If you get together a landscape prototype and you have scanned in mural orientation yous don't need to offset from the final scanned role. )

    The balance four parts take to be rotated clockwise this time. Don't forget to rotate them at the starting time.

    Load the terminal of the parts ( the 8th one/ cheque the number that the scanner gave to each file) rotate it and at present pay attending.

    Y'all are going to crop the side that will touch the already assembled kickoff row. As this was the last of the images and y'all probably includes some of the carton or the sketchbook you lot used during the scanning, it will be a good idea to crop this too. So look below what I cropped.

    Same as previously I did right click: Edit/Copy
    so I'm going to the new file and with right click I paste the image in that location. This time at the lower correct corner.

    Select move tool, zoom in to be easier for you to put it in place then go Epitome/ Flatten Epitome to prepare its position.

    Load the next part on Gimp ( the 7th one).
    Will have to crop the edges that touch on the rest of our assembled epitome.

    After croping copy and paste at your new file.

    Gear up its position.

    Next part ( 6th of the scanned)
    Don't forget to rotate.

    The 3rd office it was a chip tricky to crop for this particular painting. See below why.

    I have the clearance at the final part to do then.

    I proceeded with the last one and hither is my assembled image complete.

    Adjacent you lot take to fix them permanently in position and get rid of the overlapped just not visible parts.
    Get on the bill of fare and select Image/Merge Visible Layers.
    Click to discard those that are non visible any more than ( less data on your file so smaller final size). I take already cropped the blanc space of the new file.



    To be continued

    July xx, 2016 at 6:53 pm #1254787

    Final Stage.. A flake of color editing at our concluding prototype.

    A bit of color and brightness editing ( needed on my scanner because it tends to over do it with its scanning bar calorie-free).
    In my image a change upward to 0,81 information technology is ok only you have to play a scrap in lodge to detect what works meliorate with your scanner on your pc. I change the levels of the whole painting in order to get closer to the original.



    And a bit retouch on the brightness.

    Set.
    Consign the existing paradigm equally a .png file at Total Resolution to take it for future apply. Mine cease upward to be 3266×4444 px at its HR version.
    A sample on how it looks like a part of it at 100% size.

    Then go to Image/Scale Prototype in society to change its size.

    I made its longer side 800 px ( for web employ) and I exported this file equally a jpg with lower resolution.

    Don't save the last alter of size ( you take exported the file as jpg subsequently all) so close GIMP and if information technology gives yous a warning about discarding recent changes discard them either way.
    Here is my painting finished.

    And that'southward all folks. Yous tin ask or annotate freely from now on.
    Thank y'all for reading my tutorial. :)

    THE END

    July 21, 2016 at 1:03 am #1254777

    Thank y'all for taking so much of your time to create such a detailed and thorough tutorial, Marialena!

    July 21, 2016 at 4:59 am #1254798

    Vivid post, I can remember using my scanner as a photographic camera many years ago
    (well at least xxx) I think I even made bellows for it. information technology was all on the interweb.
    Here is an instance that I just looked upwardly all the original stuff went pop with the old hdd. http://masteringphoto.com/scanner-photography-an-culling-with-a-large-format-await/
    Camera wise I use a Fuji X20 nowadays which is rather skillful.

    July 21, 2016 at 7:18 am #1254788

    @Catwoman 2 Welcome. It might be useful to some people. In that location wasn't any such tutorial available.

    @shadye1 This is very interesting. The only matter that I accept "photographed" on my scanner is my watercolour palettes.

    Camera can not prove the texture of the paper and it is quite catchy to accept a flat /square without distortions photograph of large and very big paintings.
    My recent painting of CygOb2 f.due east at the size 106×106 cm was impossible to be photographed at the farthermost particular and resolution that I scanned it at 300dpi with any kind of average photographic camera. (unfortunately I can't postal service its Hour photograph here, but I demand it for archive and promotional reasons).

    If I was nearly to photograph it I would need a camera with large enough lens, something to mount completely flat such a large painting at the proper angle to be exactly opposite of the camera, a tripod ( I accept 1), a way to light the whole thing extremely well and of course the infinite to install all this equipment.

    But and then again, even if I had photographed it, I would had to edit this photographic image either mode.

    The above is easier and less plush method. If someone bothers to acquire the way to do the task this way, doesn't have that much time as it looks like.
    The average 56×76 cm paintings take me about 15 minutes to scan and get together and the big one took me nigh an hour.
    The scanning method is less costly, more efficient, less time consuming, doesn't occupy a lot of space and gives perfect results. Scanner is stored to a shelf and everything is neat and in its place in my rather small studio. :)

    July 21, 2016 at 8:00 am #1254779

    Very interesting tutorial, Marilena. Thank you. The merely part I didn't get was how you merged the photos then no line was shown betwixt the two parts. Is that a feature of GIMP?

    July 21, 2016 at 8:31 am #1254789

    No it is non office of GIMP. You lot can merge them without any visible lines if the parts are scanned completely flat and then they take no shadows or glares and such things at their edges.

    Usually these are produced at the edges of the area that you scan due to the plastic frame of the scanning glass surface that inevitably doesn't permit the painting to exist scanned completely flat. ( expected. The scanner is non for such large paintings).

    That is the reason why yous have to get out enough overlap clearance at the edges, ( which means that the edges of the already scanned previous part have to exist also at the next one) in order to permit you to crop out any uneven edges then merge the apartment scanned parts together.

    The basic dominion is:
    Crop whatever edges that you lot are going to attach at the already merged parts no matter on which side these are. ( top lesser left or right). Leave enough clearance during the scanning to be able to practise so. Whatever is scanned flat will non have whatsoever visible marks, shadows glares etc.

    Unless the scanning surface is dingy, ( merely then we accept a whole unlike case) has dust pilus and such things. Only this is the reason why yous take to check from time to time what is going on on the glass and wipe it clean especially if you scan very large paintings. :)

    July 21, 2016 at 8:39 am #1254790

    The easy manner to learn how to practice it is to try to assemble a smaller painting made f.e of three scanned parts. Equally soon as you lot'll piece of work the above manner in practice you'll run across that information technology is quite easy and fast and from a point and on something that yous tin practice automatically without that much thought and and so really fast.

    Simply needs a bit of practice to memorize the steps are needed to do.. but then information technology is very like shooting fish in a barrel indeed. It is copy paste and merge in a certain order.

    July 21, 2016 at 11:57 am #1254780

    July 21, 2016 at 12:31 pm #1254782

    I use a scanner besides. I can only scan 7″x11″ areas ( the left side of the scanner is bad ), and so I scan my 11×15 watercolors in iii passes. But this also works on total sheets. This gets all the details like the paper texture, and I don't accept to retouch colors. However I've found information technology's very hard to line up different parts of the picture pixel by pixel manually, simply it's doable peculiarly if you follow these directions which is basically what I am doing.

    The primary difference is I don't take gimp, but utilise photoshop. If you happen to have photoshop, of at least version CS6, in that location is an choice in the carte "Automate" -> "Photomerge" which makes this a lot easier. I did it manually for a while, and tin can say finding this feature made my life a whole lot easier.

    This opens upward a dialog, you then add files you wish to merge. These all need to be saved to disk and the same orientation ( so if y'all scan them upside down you lot need to flip them, otherwise it gets confused ). Just click "add open up files" or select the files you want to merge, and add them to the list.

    Make sure "Alloy Images together" is checked.

    So click ok.

    Assuming yous have enough hard drive space left (it needs a lot or information technology volition fail, especially on full sheet watercolors), photoshop will do all the work of lining upwardly all the pictures, adjust the edges and photos to match lighting (so a shadow on the edge is dealt with), and fifty-fifty distort the images if they demand that. Takes a minute or and then to process, but come out perfectly, but demand to crop the moving picture, merge the separate layers, and do any retouching. Much easier than doing it manually.

    Sounds like this isn't a feature of Gimp, but there are Gimp plugins that tin do this. Non used any of these, but I am assuming one of these, if they work well, will speed up the process.

    July 21, 2016 at 1:11 pm #1254778

    I agree, photomerge is a whole lot easier. At that place's as well hugin (free). The painting above would exist incredibly hard to align manually without the white dots in it.

    July 21, 2016 at ane:45 pm #1254791

    I utilize a scanner also. I tin can just scan 7″x11″ areas ( the left side of the scanner is bad ), so I scan my 11×15 watercolors in iii passes. But this also works on full sheets. This gets all the details like the paper texture, and I don't have to retouch colors. However I've found it'due south very hard to line up different parts of the motion picture pixel by pixel manually, only it'south doable especially if you follow these directions which is basically what I am doing.

    The main difference is I don't have gimp, but use photoshop. If you happen to have photoshop, of at least version CS6, there is an selection in the menu "Automate" -> "Photomerge" which makes this a lot easier. I did it manually for a while, and tin can say finding this characteristic fabricated my life a whole lot easier.

    This opens up a dialog, you then add files y'all wish to merge. These all need to be saved to disk and the aforementioned orientation ( so if you browse them upside downwards y'all need to flip them, otherwise it gets confused ). Just click "add open files" or select the files y'all want to merge, and add them to the list.

    Make sure "Alloy Images together" is checked.

    And so click ok.

    Assuming you have enough difficult bulldoze space left (it needs a lot or it will fail, especially on full canvass watercolors), photoshop will practise all the piece of work of lining up all the pictures, adjust the edges and photos to friction match lighting (and then a shadow on the border is dealt with), and even distort the images if they need that. Takes a infinitesimal or so to process, only come out perfectly, just need to crop the flick, merge the separate layers, and do any retouching. Much easier than doing it manually.

    Sounds like this isn't a feature of Gimp, but there are [URL=http://superuser.com/questions/178044/photomerge-equivalent-for-gimp/178049]Gimp plugins[/URL] that tin practise this. Not used whatever of these, just I am assuming i of these, if they piece of work well, will speed up the procedure.

    I run a Linux OS on my pc, in particular Linux Mint 17 Quiana LTS and so Photoshop is not an option for me. I'll cheque though the plugins and if they give the same results I can brand another tutorial on how you can use them.

    Even if the manual method is a bit fuzzy comparing always with motorcar methods, it gives perfect results. I scanned and replaced all the images that I have on my web site and that was a corking improvement regarding the presentation of my paintings, which is the aim of having a web-site in the first identify of course.

    @intraneel     It tin exist done on every painting and bailiwick. I used the same scanning and editing method for my concluding painting ( The Bedchamber Decoration that is now uploaded in at the Watercolour Gallery).
    But I can't post hither HR images in society to see their quality and generally I don't post HR images online because is not that wise with all these Chinese companies that steal other people's paintings and sell prints.. ( I assume that you know what is going on with these companies. They don't respect anything.. pfff :rolleyes::().

    July 21, 2016 at 1:56 pm #1254799

    Crawly thread,thx Marialena.I started using GIMP a month ago,so this is very helpful.

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