Post by: robodad on January 08, 2008, 03:09:24 PM
Thank You for the tips you guys and Nice job on that butchered photo I posted WOW !!
Post by: boneaddict on January 08, 2008, 03:22:37 PM
Post by: Elkman on January 08, 2008, 03:23:39 PM
What camera and lens is it?
If you turn it on. am it at a high contrast object and squeeze one of, what do you get? do you have a preveiw screen on it?
Is there a switch on the lens for it to be in Manual or auto focus?
Just trying to narrow it down.
Post by: Ray on January 08, 2008, 03:24:58 PM
Post by: Elkman on January 08, 2008, 03:33:06 PM
Proper AF calibration is a very time-consuming task, if done by the book.
If the tech does not care, work will be poor, and AF calibration on a camera and a zoom lens takes a lot of work and time to get just right.
When done properly, the first thing to check is the cameras AF sensor, its calibration at each and every single one of the AF points, including the "invisible" assistant AF points. Each of these points must be checked with both horizontal and vertical lines, where there are cross-type AF sensors.
(1/2 - 1 h to check and adjust, up to a day´s work to adjust if the AF sensor is not parallell with the image sensor.)
Next put the lens on a test projector and check the lens for optical alignment.
(20 minutes to check, hours of work if the lens needs to be pulled apart for adjustments.)
Finally put the lens on the camera and at each one of 8 or 10 different focal lengths, using both horizontal and vertical lines, check and adjust AF calibration.
(1/2 h to check, 15 min to adjust per focal length that needs adjustment)
There are two calibration tables in each lens. One for 1-series cameras, and one for non-1-series) These use different types of AF sensors, so calibration has to be made from scratch for each table.
The techs are supposed always to check calibration with two cameras, one of each category, and perform calibrations as needed for both tables.
The problem is that in most countries Canon has outsorced much of this work, and Canon will only pay a small flat-rate amount per lens that gets calibrated, irrespective of the amount of work that is actually done.
Simply put, this system more or less forces the companies involved to cut corners, and middle managment from financial necessity tend to put pressure on the techs not to spend too much time on the lens calibration work.
Having a few carefully shot test-charts clearly showing front- or backfocus, very effectively yet politely communicate you are customer who knows how to check the quality of the calibration work.
Basically put, if manual focus ever can obtain a sharper image than AF, at any focal length and with any of the AF sensors, the calibration has not been properly done.
With a camera with live view, this is extremely easy to check:
Use a tripod. AF on a detailed flat surface, at a distance about 50 times further away than the lens focal length. Switch to live view. Zoom in at the AF sensor used. Look at the sharpness. Then manually focus very slowly until the image is as sharp as possible. If this sharpness is better than the sharpness straight after AF, then there is room for improvment.
This test needs to be done several times over, to make sure a momentary glitch from the AF system has not given misleading results.
Post by: popeshawnpaul on January 08, 2008, 03:42:30 PM
I use two factors on depth of field...depending on what I'm shooting. If I'm shooting wildlife, I always use the fastest or lowest aperture on my lens...period. You didn't spend an extra thousand dollars on that F4 lens just to use it at F5.6 or higher... The lower the aperture, the more out of focus or less depth of field you will get. I have shot with a F1.2 and F1.8 lens, and the depth of field is so shallow that you could shoot a picture of someone and their eyes will be in focus while the end of their nose and ears aren't... There are two exceptions to using the wides aperture...1. there are two deer in my picture and one is standing farther back than the first and I want the heads of both to be in focus...and 2. I am using a cheap lens and if I stop down that cheap F5.6 lens to F8 the images will be much much sharper even though there will be little background blur...
For landscape, you generally want everything in focus. Like Elkman said, you don't want the smallest aperture because it is often not the best quality for a lens. Most lenses have a sweet spot and perform really well at F16-F22 and those apertures will have a large depth of field. One mistake I see some make...they use F16 and then end up focusing to infinity. Everything looks in focus even the close up stuff until you get it blown up on your computer at home. Then you will notice some of the close foreground subjects will be slightly out of focus. You will have better success with a high aperture and focusing on a relatively close subject, and in turn your distant background objects will tend to be in decent focus.
For example, if I'm taking a picture of a tree that is 10 feet from my camera and Mt. Rainier is in the background, I would focus on the tree and shoot it at F22. That way, the mountain and tree would be in focus. If I focused on the mountain, the tree won't be in sharp focus even if you are using a small aperture like F22.
Hopefully some of that makes sense... (man, I have been stuck in my office for two days with no court, I need to get out and do some trials or something. I'm just sitting on here surfing all day :'()
Post by: huntnphool on January 08, 2008, 03:56:52 PM
Sounds like there is a poacher out there that could use your services ;) Just dont try to hard to get him off. :chuckle:
Great info Pope, keep it coming.
Post by: robodad on January 08, 2008, 03:58:20 PM
Maybe there is no way to calibrate it, I'll see what adjustments I can make with it.
My wife went and bought herself a new canon powershot SX100 IS camera because she was so pissed that the Minolta took such bad pictures and I figured it would be a good one for me to play with outdoors if I can get it to take better pictures, and I want to learn how to use the features it has so i can take better pictures then hers and show her that she didn't need the new one. :chuckle:
I've always wanted to learn how to take better pictures but never more then I do now !!!
Thanks so much for the information and tomorrow I'll take some other pictures and post them to see what you think.
Allen...
You guys posted before I could but as you can see my camera is no match for yours and maybe I should be happy with what I am getting from it, I so appreciate the information, I don't think I will mess with the AF on mine cause it looks like a can of worms I don't want to open.
Someday I will have a great camera but for now I have to do the best with what I got. I will read your posts over and over to let it sink in and hopefully I can get better at this picture taking business.
Thanks again guys.
Allen
Post by: popeshawnpaul on January 08, 2008, 04:04:30 PM
shawn
Allen - with that camera there isn't a whole lot you can do. Autofocus calibration is a complex deal and you can't do anything about it with a point and shoot. Just try and mess with your white balance and you'll be on the right track.
Post by: robodad on January 08, 2008, 04:33:05 PM
What do you mean by "shooting in the raw", I have a picture in the back of my mind but really don't want to go there LOL.
Post by: boneaddict on January 08, 2008, 10:44:53 PM
Post by: boneaddict on January 08, 2008, 10:46:03 PM
http://hunting-washington.com/smf/index.php/topic,3356.0.html (http://hunting-washington.com/smf/index.php/topic,3356.0.html)
Post by: ICEMAN on January 08, 2008, 11:06:53 PM
... (man, I have been stuck in my office for two days with no court, I need to get out and do some trials or something. I'm just sitting on here surfing all day :'()
No wonder lawyers cost so damn much! Now I know what my brother does all day! :chuckle:
Post by: robodad on January 10, 2008, 04:13:41 PM
So I appreciate your input in this matter and maybe I can someday take better photos !!!
Post by: popeshawnpaul on January 10, 2008, 07:58:04 PM
http://www.dyxum.com/lenses/index.asp
Then you just need to find a good Sony DSLR and you are in the game for cheap... I see two relevant ones. Probably the one you want is the A100 at $586 and it gets good reviews for a 10 megapixel camera. If you get a big tax return, you could splurge on the A700 for $1300 but that seems a bit advanced and expensive for what your experience level. What lenses do you already have? Are they good or cheap ones? If they are good this is a no brainer. If they are cheapo's then you could just as easy to any brand you want.
shawn
Post by: robodad on January 10, 2008, 10:35:17 PM
http://www.bestpricecameras.com/prodetails.asp?prodid=615855 (http://www.bestpricecameras.com/prodetails.asp?prodid=615855)
Should be a good tax return, it usually is but is spent already, that is how I pay for lodging when I go to Republic for deer season and gas to get to Wisconsin for Thanksgiving with my folks and deer hunting there, oh and ice fishing !! fun stuff :chuckle:
I will try to get the money together though if you think this set up will work, I know it is not a Nikon but I have to work with what I got you know what I mean.
Give me your thoughts on this, hopefully I can get away with it for only the $400 that would be awesome !!
Here are the lenses:
http://www.dyxum.com/lenses/detail.asp?IDLens=43 (http://www.dyxum.com/lenses/detail.asp?IDLens=43) http://www.dyxum.com/lenses/detail.asp?IDLens=50 (http://www.dyxum.com/lenses/detail.asp?IDLens=50)
Thanks again for your time.
Allen...
Post by: popeshawnpaul on January 11, 2008, 12:11:02 AM
Those lenses will work fine with this camera. I think that is the cheapest way into a nice dslr. From the sample images I have seen, it's as good or better quality than Nikon's cheaper cameras. This combination will be much better quality than any point and shoot. Remember, the sensor has a 1.5x magnification factor, so your small lens will be a 52-120mm and your telephoto will be a 105-300mm. Both lense are on the slow end, but remember this camera has built in image stabilization. Maybe on your next tax return you could buy a nice telephoto or something.
Shawn
Post by: robodad on January 11, 2008, 08:09:26 AM
I'm really glad I can still use some of my original equipment and still upgrade my camera, I appreciate your expert opinion and maybe in the not so distant future I can post some better photos.
My telephone takes better pictures then my Minolta PAS :bash:
Post by: jackelope on January 12, 2008, 08:31:30 AM
Quote
. Its actually what I have been doing all my stuff in since I don't have the computer program to work with Raw
bone..if you got the software that came with the fz that i got, you can work the RAW images. it's the silkypix developer. not sure how much or what you can do, but it will take care of the raw images.