Okay, I know we’ve got a few people here that have some experience with Digi-cams and posting photos to websites and stuff so I could use a little advice:
I just got a Canon PowerShot G1, and I’m getting ready to put some stuff up on ebay. Of course I’ll need to make some photos available and I’m trying to find out:
A) what resolution/compression combinations work best for pictures that will be viewed primarily on the web? Of course I’d like to make the file sizes as small as possible without losing too much quality.
B) What are the options for storing digital photos on-line these days? Is Photopoint a good way to go, or is some other sort of image hosting service better for personal storage (don’t have a regular PC I can use at the moment).
Most image programs have a selection for adjusting a picture for email. This setting reduces the resolution and compresses it (usually as a jpeg). Just accept the default settings first and see how big the file size gets. Somewhere around 50 or 60 k should be fine.
a) A minimum resolution of 72 dpi should be used. This is because monitors run at that speed (or something like that). It’s also pointless to go very much above that dpi size - as VDU’s can’t make the most of the resolution and it uses more disk space. That said, I usually scan photographs at 100 to 200 dpi, depending on how big they will be displayed - and then save them as JPEGS for website viewing. The bigger the image, the more dpi I use, but that’s really just my whim and not a scentifically proven method. 100 dpi should be fine (and is my standard) for images not more than about 300 pixels square.
Hope that helps,
Steve
[ This Message was edited by: StevePower on 2002-01-04 19:38 ]
I confirm - if they will only be displayed on a computer screen, 72 pixels is all you need. I usually use 100 out of habit. If you use Photoshop you can save in jpg at a lower quality and it won’t manke a visible difference. My Photoshop 4 gives an option to save in Quality 1 through 10, and 5 through 10 all look the same on the computer and make a big difference in file size.
Loren,
Not all picture editing software is created equal. Test your images by dropping them into your browser for final approval. I once setup 30+ images that looked great in my ‘paint’ software and extremely dark in Netscape or Explorer.
Thanks everyone, what you’ve said makes sense to me. The camera came with Photoshop 5.0, so I think I should be able to do that stuff when I have access to a PC.
However, I see now I made a mistake, I should have explained differently…
Since I won’t always have access to a PC, and I will likely be uploading direct from the camera to a website or image bank, I’m wondering what resolution I should set the camera to. It’s a 3.3 mega pixel camera, so I can choose from three different resolutions, then 3 different compressions. For Example:
I can choose between three resolution levels, 2048 x 1536, 1024 x 768, or 640x 480.
Then for each of those settings, I have to choose from 3 compression levels. So basically, at the time I take the photo, I can be creating a file size between 2048KB and 88KB, with seven or 8 steps in-between depending on the combination of resolution and compression settings I choose.
For me, the idea right now is that I’d like to record the photos (at the camera) at the lowest file size that will still yield good quality photos when viewed on the web. This way I can get the most useful photos on one relatively small 16MB CF card and reduce down load times. I do realize I could do this stuff after the fact in Photoshop, but more often than not I can’t access a PC at this point, but I can upload strait from my Webtv reciever, which I’m using to write the rambling message. Whew!
Okay, thanks again, I did find the other advice helpful, I’m just looking for a bit more.
I would choose the 1024 x 768 resolution. As for quality level, set up a few shots (outdoors, indoors, contrasty, many colors) and take one of each setup at each quality level. From those results you should be able to choose the level of quality you want to use. Typically the lowest (ie “good”) level is sufficient. If you are certain you will only be using the images online and in small formats, the 640 X 480 resolution and lowest quality should be sufficient.
I agree that the 640x480 resolution should be enough for ebay ads if you can not access enhancement software. Loading fast is always better than slow. One thing to enhance images at low res, is to overcome the camera’s light reading ability and add contrast to your pics. If you’re trying to show a black whistle, do not use a white or light colored background. If you use a similar tone, your camera will record better detail in the image. Likewise for light colored objects, use an offwhite or neutral background. When you can get to a PC, ACD Systems has the best software for enhancement that I have seen. Not as powerful as Photoshop, but for internet pics, still powerful and very, very quick. ACDSee is at http://www.acdsystems.com.
Mike
TRUTH is Unchangeable, No Matter What is Politically Correct!
Finally a topic that I know something about I’m not a digital graphic designer but I work very closely with one on a daily basis so I’ve picked up a fair bit of knowledge on this topic (actually I’m using my GD’s workstation to write this message - geesh, he has two 21 inch monitors!)
DPI actually has to do with printing images or scanning them from printed material; it has no bearing on images intended for screen display. Its true that most computers display at 72 DPI but that isn’t a hard-and-fast rule anymore. The actual system DPI is a function of the operating system and not the monitor. Windows can be, and frequently is, set to display at 96 DPI. Some high quality monitors can actually do about 120 DPI but there are no operating systems that can take advatnage of that yet. What really matters for Web work is the actual resolution of your image - DPI is irrelevant. For example, if your monitor is set to display at 800 x 600 pixels then a 400 x 300 pixel image will take up 1/4 of your screen.
Loren, if you consider that most people (about 70% as of December 31, 2001) still have a monitor resolution set to 800 x 600 then even an image of 640 x 480 will use up most of their useable screen area inside a browser window.
As far as compression is concerned, most JPEG Web images use very low quality settings simply to reduce download times. Even low quality JPEG images are actually pretty good.
If you want to print your images then resolution is an entirely different matter. Most colour printers these days can do near-photo quality (1200 or 2400 DPI) so you basically want the biggest, highest quality image you can get if you want to print it with good results.
If you do have the chance to pull your images into Photoshop before uploading to the Web one thing you might want to consider is increasing the image colour saturation (by 10 - 15%). My GD says this helps images look more “alive”.
As StevePower suggested, you can capture your images at a higher resolution and then resample (resize) them in Photoshop - this is particularily useful if you want to use the same image for print and for the Web.
Once again, thanks to everyone, I’ve gotten good information from all, and this has all been very helpful indeed.
Gary, you’ve just done a fabulous job of tying the bits and pieces (that were so generously supplied by others) together for me. I have a clear picture (ha ha) of how to proceed now with the resuolution issues new - cool!
Erik, that would explain why so many eBay pictures are lacking in size and quality. From time-to-time I have seen large images. Either they’ve gotten around IPIX size limit or the images were linked from other websites.
Loren, if that’s the case, put your full-size pictures online somewhere and link them to your ad. I have a commercially hosted website with plenty of bandwidth available. If you want, e-mail the images to me and I’ll upload them to a directory for you to use.
For what it’s worth, the documentation that came with my Nikon Coolpix995 suggests that the “VGA” setting (@ 640 X 480 pixels, which yields an image of approx. 3.1 inches X 2.4 inches)is good for “posting on a 13-inch monitor, sending image data via e-mail, or posting on an internet homepage.”
I hope this is helpful, but I think you have already received sage advice.
Thanks for the ebay info, very interesting and helpful.
Tony,
That’s very kind and generous of you…Are you feeling okay?
Seriously, thanks man, I may just take you up on that.
Tom,
I do appreciate the additional confirmation coming strait from a Nikon manual. It’s funny, the Canon manual is surprisingly basic for one of their top of the line cameras. Hmph.
All,
Well it appears I may have another problem anyway: Looks like my browser’s dedicated e-mail program automatically compresses every image to a very small size, resulting in significant loss of quality. When I e-mail Hi-Res photos, they show up looking about the same to the receiving person as the very low res photos I send.
Looks like it’s PC or bust after all…
Thanks again though everyone, this has been educational, and still quite useful to me
