iMac 2.8 - Boost RAM or is something wrong?

Discussion in 'iMac' started by bunger, Sep 2, 2007.

  1. bunger macrumors 6502

    Joined:
    Mar 1, 2007
    #1
    I have had the 24" IMac 2.8GHz with 2GB RAM for about 2 weeks now. I should first say this is my first "real" Mac - that is, I dualboot a MBP for work but don't use it for imaging, etc. With that said, I have recently been running iPhoto and Aperture side by side and am now noticing some sluggishness in both.

    I shoot Nikon's RAW format and IPhoto takes 3 seconds from the time I click an image to the time it fully renders the image such that it is not pixilated or blurry. Aperature is a bit worse when applying adjustments... seems to lag a bit before applying exposures, etc.

    So my question is.... 2.8 and 2GB sure seemed like a lot of horsepower, but am I just not used to the Mac world and really need to boost up to 4GB OR is something just not quite right?

    tia,
    Bill
     
  2. A Pittarelli macrumors 6502

    Joined:
    Jun 1, 2007
    #2
    that doesnt sound right at all. how big are the images youre working with? you can try repairing your disk permissions, someone will eventually suggest that. just type disk utility into spotlight and go from there.
     
  3. bunger thread starter macrumors 6502

    Joined:
    Mar 1, 2007
    #3
    They range between 3.5MB and 5MB each. And I will try repairing permissions and we'll see what happens...
     
  4. motulist macrumors 601

    motulist

    Joined:
    Dec 2, 2003
    #4
    I think 5MB is a big enough picture to render on screen that there'll be a second or two to put it on screen. It's not a Mac vs. Windows thing, there'd probably be the same delay if you booted the iMac up in windows and tried to open the same photo.

    The bottle neck causing the delay is probably the hard disk speed. I don't know how fast the HD is in an iMac, but there's a reason why photo professionals buy a pro model machine and consumers buy an iMac. The speed and power of a computer are limited by a LOT more factors than just CPU speed and amount of RAM.
     
  5. bunger thread starter macrumors 6502

    Joined:
    Mar 1, 2007
    #5
    Is the drive speed in the iMac a 7200 or 5400? If it is a 5400, I guess that makes sense, but I would like to think it is a 7200.

    Also... repair permissions didn't have any impact..
     
  6. irishgrizzly macrumors 65816

    irishgrizzly

    Joined:
    May 15, 2006
    #6
    If the stuff you're doing is making you money – buy a mac pro with dual Raptors with 10,000 speed, you're make back the extra cost in no time!
     
  7. motulist macrumors 601

    motulist

    Joined:
    Dec 2, 2003
    #7
    For most technical questions, the answers aren't hard to find on the web. Your computer has a 7200 rpm drive. The only Macs I use on a regular basis are quite old, so my expected performance bar is somewhat out of date, but on my 1 ghz powerbook it take about 2 or 3 seconds to render a photo that's a 2 to 3 MB JPEG image, so I don't think it's unreasonable that a newer machine will open a 3 to 5 MB RAW image in the same amount of time.

    I would bet that Nikon specific RAW image decompressors are less optimized than the decompressors for the common and ancient JPEG format. Try opening up a few JPEG in the 3 to 5 MB range and see if the same delay occurs.

    If you want to see if anything is hogging resources on your machine, open up activity monitor, selected to show "all processes" and see if anything is needlessly stealing CPU%. Also look under the Disk Activity tab and see if something is using your disk needlessly.
     
  8. Hibbsy macrumors member

    Joined:
    Aug 12, 2007
    Location:
    UK
    #8
    I have same 2.8 imac with 4Gb of memory and when working with Nikon RAW 5Mb files see a similar delay (2 secs ish) from disc. Not quite the 3 seconds you mention.

    iphoto seems to cache the last viewed photo in memory once you have viewed it provided you stay 1 photo either side it seems to be instant.

    I don't use RAW most of the time and its not an issue for me, unless you are working professionally using RAW all day every day I would guess the same would be true.

    More memory may improve the cache operation and limit the number of times the RAW file is read from the disc.
     
  9. mavis macrumors 68040

    mavis

    Joined:
    Jul 30, 2007
    Location:
    Tokyo, Japan
    #9
    Three seconds? I wish!! I'm going to be getting that same machine you've got (I already have the RAM from OWC, just waiting on a little cash to free up for the iMac!) but for now I'm using Lightroom to process my Canon RAW files on my 3.2GHz P4 with 1GB RAM (running WinXP Pro) ... It usually takes at least five seconds to render a preview-sized image for the first time (although I just timed it at 10.2 seconds!), but if I view an image at 1:1 zoom, I'm looking at about a ten-fifteen second wait (again, I just timed it at 19 seconds). It's far worse when I've got Photoshop open on the other monitor, those times are probably doubled. I know a lot of that has to do with the fact that I've only got 1GB of RAM in this box, or the fact that my CPU is only single core - but it doesn't really matter - it just means that my new 24" 2.8GHz iMac with 4GB of RAM is going to run circles around this thing! :D

    So, thanks for your post. It's nice to know that I can look forward to images opening 5~7X faster than they do on my current machine. I can't wait! :)
     
  10. bunger thread starter macrumors 6502

    Joined:
    Mar 1, 2007
    #10
    WOW! Thanks for all of the great feedback!! I was about ready to dump by 2GB and boost up to 4, but I may wait a little while now.

    And just for clarification, the image will display immediately, but it is almost a progressive display. The first render is pretty blurry and pixelated, the second is a bit more sharp, and the third render is the perfect image.... but they don't occur gradually - you wait a second and the image sharpens, then 2 more seconds and the full image is displayed - just strange. Aperture does not do this, though I think it auto-generates previews in the background.

    As a follow-up note: I exported one of my 5.3MB NEF files to a full quality JPG and it was only 1.5MB in size. Even so, I tried opening it in iPHoto and it fully rendered within a second.

    Thanks again to everyone!
    Bill
     
  11. motulist macrumors 601

    motulist

    Joined:
    Dec 2, 2003
    #11
    Just be aware that even at its highest quality setting, JPEG is actually a lossy compression format.
     

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