Help! Ended up with 964MB image from my Epson V500...

[simon_bruxelles]

<p>I am embarrassed to admit I am having big problems working out even the basics with my new Epson V500 scanner. I am trying to scan B&W 35mm negatives but I am ending up with vast files of up to 1.01GB! <br>

Can someone explain the relationship between "resolution" - presumably the detail which the negative is scanned - and "scaling" - presumaby the size of the on screen image? I don't recall having either "scaling" or "target size" controls with my previous admittedly very basic flatbed scanner, which may be where my problem lies. <br>

The settings I am using in "Professional mode" (as it seems to offer the greatest degree of control) are document type: film, film type: black and white negative film, destination image type: 48-bit color, resolution: 2400 dpi, document size 35mm x 21mm (roughtly full frame), target size 35mm x 21mm, scaling 100 per cent. I have swtiched off all the other imaging controls such as dust reduction, ICE etc.<br>

This produces a reasonable size image for on screen editing allowing room for cropping but the file is still 37MB which is too large for my purposes though a lot better than the 964MB file I got when I set "target" to 5x7in, which seemed a reasonable size to want to print at.<br>

My brain tells me that when viewing "actual pixels", "scale" and "resolution" should just be different expressions of the same thing, so I don't understand how you can set one independently of the other. <br>

My other equally dumb question is what file compression should I be using when saving the untitled image? I am being given the choice of Photoshop, Photo Project Format, TIFF, Jpeg 2000, Photoshop PDF and Photoshop RAW. Unfortunately there is no option for an ordinary Jpeg and the iPhoto editiing programme on my iMac does not recognise Jpeg 2000.<br>

Thanks for any help, Simon</p>

<p> </p>

[brian_m2]

<p>I'm no scanning expert, but I suspect that the problem is with your setting of 2400 dpi. Very high quality prints up to 16X20 can be made with only 300 dpi. I know that the scan dpi and print dpi are not the same thing, but there's some correlation, I believe. I think you've set the scan resolution way way way too high. Those more knowledgeable than I can confirm or correct.</p>

[patricklavoie]

<p>That is the common problem among user..they dont know at what and why ppi they should scan.. and they end up with big file for nothing.</p>

<p>So heres a basic concept that should help you (i think i wrote it 3 times in the last month..; )</p>

<p>1_<strong>what size do you need in the end?</strong> let say 8x10inch.</p>

<p>2_<strong>at what ppi do you need your final image?</strong> 72ppi, 200ppi, 300ppi? let say 300ppi.</p>

<p>3_<strong>what size is you original?</strong> , let say 1inch in is shorthest side (35mm short side)</p>

<p>4_<strong>how many time this short side fit in the short side of the size you need?</strong> in this example 1 inch fit 8 time in 8inch.</p>

<p>5_so you do 8 x 300ppi = 2400ppi. tadam!..heres at what resolution you need to scan your 35mm if you dont crop it and if you want to keep it full frame.</p>

<p>A 2400ppi 35mm scan as a 16bit grayscale is around 22megs whenn open in Photoshop, will of course be less when save as JPEG depending of the compression or as TIF with or without LZW...</p>

<p> </p>

[patricklavoie]

<p><em> I know that the scan dpi and print dpi are not the same thing, but there's some correlation, I believe. </em></p>

<p>Thats because scanner still dont use the correct *name* for it, witch is PPI as for Pixel Per Inch, and they should not use the term DPI, witch stand for Dot Per Inch..a printer mesure. You should use DPI only when talking about print, like in this example;</p>

<p>I have a <strong>300PPI</strong> images <strong>in Photoshop</strong> , and i would like to <strong>print it at 1440DPI</strong> with my <strong>Epson printer</strong> <em><br /> </em></p>

[hal_b]

<p>Simon, I think your problem is with the scaling. You don't want the Epson software to do any scaling (resizing). Just let it scan the image and save it. Period. That's it. Scanning software scans, photo editing software edits photos, and printing software prints. Things get messy when you mix up this stuff.</p>

<p>Each function uses "dots per inch" or "pixels per inch" in its own fashion. The scanner needs to scan at its native resolution for the cleanest possible scan. I believe that's 4800 ppi for your scanner. I usually scan at 2400 on my scanner, to save time, but I don't get quite as good results as I do at 4800. You should probably output as a TIFF, if that is your best option.</p>

<p>Now you need to open the file in iPhoto (I'm not familiar with this) and use it to crop/scale your photo as necessary prior to printing. If you are printing at 5x7, then scale to 1500x2100 pixels MINIMUM using your best practice, to achieve the cleanest results prior to printing. When you output to your printer, use your printer's best DPI resolution. As Patrick pointed out, this can exceed the photo's resolution, as the printer will lay down more ink to achieve the higher resolution, and produce a more saturated (read dense) image.</p>

[aaron d]

<p>Simon,</p>

<p>Basically, you've got two main variables when you scan: resolution and size. If you increase either your file size increase, or vicy versy. If the dimensions of your scan (I think it'll be called "output" dimensions) increase, you're getting the same dots per inch, but more inches - so more dots. </p>

<p>There are two ways to approach a scan - if you don't know what you'll do with the scan - maybe you'll post to the web, or make a 5x7 print, etc. - then you will probably want to scan at your 2400 dpi and at the "native" size. In the 35mm case, that's 1x1.5". If you know you're only going to want a 5x7 print, you would scan at your final size AND resolution, say 360dpi and 5x7". If you scan to 5x7" and 2400 dpi, you're getting many more dots than are actually "legit", if you know what I mean - it's creating resolution unnecessarily and without providing any additional information. You're just dividing the thing into finer pieces. That's why the huge file sizes.</p>

<p>The other variable is channels - if you only need B+W, you only need one channel. If you're doing color, you'll need three - one each for R, G and B - and the file will be three times bigger, assuming size and res stay the same.</p>

<p>I would say save your scans to PSD if you use PhotoShop - or TIFF is the more universal and is good, Photoshop or otherwise. Keep it as your master file and save any edits in a format appropriate to the intended use of the image. JPEG only if you know you'll never want to touch it again, because JPEG throws out "unnecessary" information to make the file so small.</p>

<p>There are a lot of other nuances that you'll pick up as to you read and fool around with it, but that should get you going..... </p>

[StuartMoxham]

<p>Leave the scaling set to 100% and the target size as original original. Set the ppi to 2400 and you will get a scan of around 3300x2060 pixels. If the bit depth is 48bit that gives a 39mb image if the bit depth is 24 bit you get around 20mb scan. For a 5x7 inch image at 300ppi around 1500x2100 is what you need. Set the ppi in epson scan to 300ppi and set the target size to 5x7 inch the scaling will change to the required percentage by itself. Save the scans as tiffs to preserve as much detail in the scan as posible.</p>

[simon_bruxelles]

<p>All sorts of strange things happening...<br>

First, many thanks for the helpful responses. At last I think I am getting my head around the concept of resolution and how it relates to scaling. I had previously thought the only thing that mattered was the resolution at which you scanned the negative.<br>

Now, can someone explain what's going on. I changed the settings, as recommended above, to image type: 16-gray scale, resolution: 4800dpi, scaling: original. This produced a 45MB Tiff file which I then "exported" as a Jpeg to make it a more managable size for editing in iPhoto. The Jpeg was originally 6.7MB but when I tried to edit it the image went completely black. It then reappeared as a "solarized" image and after I reopened my photo library had reduced to a very dark 1.7MB file. Here are low res unedited copies of the original Tiff image and one of the degraded Jpeg. Any ideas?<br>

<img src="http://img.photobucket.com/albums/v721/debrux/marf_2x.jpg" alt="" /><img src="http://img.photobucket.com/albums/v721/debrux/marf_4x.jpg" alt="" /></p>

<p> </p>

[john_simon5]

<p>iPhoto can't handle grey-scale images. Images in iPhoto need to be in an RGB colour space otherwise weird things happen.</p>

[simon_bruxelles]

<p>Thanks John, I am slowly getting there!</p>