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bphillips330
25th of October 2006 (Wed), 14:25
Wow, so glad I found this forum and website. I have enjoyed taking photos for a long time. While in high school I did a ton of black and white and loved the art of taking and developing. While in college did not have the most time to dabble in the art anymore. Worked at circuit city and bought a decent digital point and shoot and have taken some pretty good shots.

My wife has recently let me go out and finally buy a digital slr (rebel xti/400d) which I enjoy allot. We recently got back from our vacation in Gatlinburg Tennessee and I took some good nature and waterfall pictures. Some questions I have found while playing with camera in the field is.....

1) why with higher iso do you get fewer pictures on 1 gig card? Does an iso 800 save more info than say a 100 iso? Ok, well I know it does, but what is reasoning behind this? I would think the sharper iso 100 would have more info and the picture with more noise (iso 800/1600) would have less info.

2) on a 10 meg camera, is there that much noise on an 800 iso (for indoor photography)? I have a new son (16 months old) and have been shooting pictures all the time. I know with film, lower iso=lower grain. In all reality these will only be processed at 4x6, maybe 5x7, and very few large prints. Will there really be a noticaple difference on prints with such a large magapixel rating say at 4x6 prints. At what point (print size) do you start seeing noise. Largest prints I will most likely do are 8x10 with very few poster size prints.

3) I have been getting some books from the library and constantly reading more and more posts here to better my photography. I have a good grasp on composing and rules of thirds and all the fun stuff to make better pictures and framing of pictures. Are there any good books people would recommend that gives more info or techniques for more advanced photographers? Most of the stuff I keep seeing in books is for beginners.


again, i will be doing more posts as i learn more. Thanks for any help.

Wilt
25th of October 2006 (Wed), 14:35
1) why with higher iso do you get fewer pictures on 1 gig card? Does an iso 800 save more info than say a 100 iso? Ok, well I know it does, but what is reasoning behind this? I would think the sharper iso 100 would have more info and the picture with more noise (iso 800/1600) would have less info.

JPEG compression is most efficient with large areas of contiguous color. High ISO adds noise to the image, so the compression cannot be as effecient, leading to larger final file sizes.

2) on a 10 meg camera, is there that much noise on an 800 iso (for indoor photography)? ... Will there really be a noticaple difference on prints with such a large magapixel rating say at 4x6 prints. At what point (print size) do you start seeing noise. Largest prints I will most likely do are 8x10 with very few poster size prints.

About 10Mb camera and noise...the answer is 'it depends'. Canons are less noisy than other brands at high ISO.

At 4x5 you aren't likely to notice much noise, and even at 8x10 the amount of noise you see is probably pretty easily tolerable except to the finicky or those striving for ultimate image quality. This is particularly true if your eye is based upon past results with film and grain!

coreypolis
25th of October 2006 (Wed), 14:44
I'm taking a guess on the iso filesize, but I'm guessing the noise is the issue. Its presenting more colors infront of the sensor to record. A very colorful picture is larger than a all one color image, and I'd suspect that has something to do with it. But you are right, iso effects file size.


There will be noise at iso 800, getting the proper exposure is key. under exposure will increase the noise to most likely unuseable levels. Noise ninja or neat image are great tools for reducing noise after the fact.

in all likely hod, you won't be blowing high iso images up, think about your favorite images, and look at the lighting conditions you took them under. Almost always under great lighting conditions

Mark_Cohran
25th of October 2006 (Wed), 17:08
3) I have been getting some books from the library and constantly reading more and more posts here to better my photography. I have a good grasp on composing and rules of thirds and all the fun stuff to make better pictures and framing of pictures. Are there any good books people would recommend that gives more info or techniques for more advanced photographers? Most of the stuff I keep seeing in books is for beginners.


What specific techniques are you looking for? Bryan Petersen has two very good books out that I consider more advanced: Beyond Portraiture and Learning to See Creatively. There are also a number of Photoshop books out there that have techniques for the advanced photographer, Photoshop CS2 for Photographers being among my favorites. If you really want to get advanced,
Light: Science & Magic : An Introduction to Photographic Lighting is a great book. It's out in its 2nd edition now.

Mark

Mark_Cohran
25th of October 2006 (Wed), 17:09
Oh, BTW, welcome to the forums!

Mark