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07/12/2007 03:20:11 PM · #1 |
i bought my 1st slr thinking i will mostly depend on the AF system..but it is really annoying when am focusing on a subject ( especially in macro mode) & the camera refuses to shoot !! it keeps giving me either a sequence of flashes or just keeps beeping & it shoots when i don't want it to shoot !,it says in the manual (as far as i remember) that in this case i have to move away or get closer from the object but neither of them works..
i currently do all the focusing in manual mode which is really depressing ( sometimes i get good shots but most of them are out of focus)..
i've nearly smashed my camera today .. this is really depressing
any tips or links to help me out would be much appreciated
am using a tamron 70-300/4-5.6 macro |
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07/12/2007 03:25:48 PM · #2 |
How close are you focusing? There is a minimum focus many lenses about 1.5 feet. Macro zooms are kinda cool cause you can stand a good distance.
The Rebel T2 35mm is the same way and manual focusing is good. On Pentax point and shoots you hit the green button and it shoots even if its not correct 100% lol.
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07/12/2007 03:27:08 PM · #3 |
I dont use an xti, but my nikon wont shoot if im too close to the subject. I have to be at least a foot away with my lense. Also, the autofocus doesnt work if there are lots of subjects at different distances, if the subject is very high contrast or low contrast. Putting the autofocus system on dynamic mode seems to enhance this problem.
Maybe you could try picking one focus point (like center af) and try focusing. If there's still a problem there might be a defect in the focusing motor.
Message edited by author 2007-07-12 15:27:51. |
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07/12/2007 03:28:50 PM · #4 |
manual is right, sounds like you are too close to the subject. Your focus distance is based on what lens your using not the camera. the beep means you are focused.
Another culprit could be what you are using as a focus point. I have the rebel XT which is essentially the same as yours just a bit older w/ some differences. Anyway, there is a button which shows me my focus points. I can pick a specific point or have the camera pick one automatically. If its picking one automatically, it may lock on a focus point but not the part of the frame you want. For example if it was a portrait it might pick the very bottom focus point when I wanted the top. Check the manual, I am sure this button is on your camera.
Also, there is an adjustment you can make that changes the focus of the viewfinder. Look into your camera and make sure all the numbers and light meter are tack sharp, if not play with that adjustment until they are sharp.
Hope that helps. |
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07/12/2007 03:28:58 PM · #5 |
| LK is right on one note that i forgot all about. AF points their selectable for a few reasons. One difficult backgrounds or even forgrounds objects in the way. Focusing on objects at an extreme distance. Never used them too up close but i guess that would help too! |
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07/12/2007 03:31:23 PM · #6 |
The only thing that bothers me is that he says all his focusing in manual. Which rules out the 'too close' scenario, in which case even manual focusing wouldnt work because it is beyond the range of the lense.
Hmmmm... |
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07/12/2007 03:32:16 PM · #7 |
Ahh just read the part where it says "sometimes i get good shots but sometimes theyre out of focus. Looks like he probably is trying to focus too close. |
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07/12/2007 03:38:26 PM · #8 |
Perhaps you're getting motion blur. Are you using a tripod?
From experience I know that it can be difficult to shoot macros with that length lens when you hand hold. Shutter speed should be fairly quick, too, when working without a tripod.
BTW, the specs for your lens indicate Minimum Focusing Distance: 59in.(1.5m) in normal setting/ 37.4" (0.95m) in macro mode (f=180mm-300mm range) This is similar to a lens I use and since I'm only 5'3" tall it means it's not possible for me to shoot a macro of my own toes....unless I increase the zoom. :)
Message edited by author 2007-07-12 15:43:15. |
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07/12/2007 03:51:53 PM · #9 |
There are alot of factors that could be affecting focus here.
The lens you listed has a minimum focus distance of 37.4in/.95m at focal lenghts of 180-300mm in "macro mode", for a max. magnification of 1:2 at 300mm and 37.4 in.
If you are close to the 37.4 in. limit, focus may be difficult. A tripod will help alot, as small camera movements will result in out of focus shots. The lens will also have a lot of hunting to do if it loses focus, be patient with it.
Subject contrast will also affect the camera's ability to lock focus. If there is little contrast in your subject, manual focus is your best bet. You could also select a single autofocus point, place it over a high contrast area, focus, and slightly (and carefully) recompose.
Autofocus mode could also be a complication here. Single shot will be your best bet on a tripod or when using focus/recompose. The beep will sound when focus locks, and it will stay locked as long as you half-press the shutter. When hand-holding for macro, I've had good luck in servo mode. There will not be a focus confirmation beep as the lens will constantly be adjusting focus. The camera will let you shoot at any time, in or out of focus. Once thecamera finds the subject, you wil hear and feel a series of small focus adjustments, at this point just try to avoid forward/backward movements and mind the min. focusing distance.
Of course, a tripod is your best friend here.
Macro takes practice. It can be difficult, but also rewarding. Good luck. |
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07/12/2007 04:15:05 PM · #10 |
i tried to move away from the object ( about 1.5-2 meters) but it really doesn't help much The AF locks but it still won't shoot & if i got lucky i get something far beyond from being macro :)
maybe i will get this by practice..
thanks all for your help that is really much appreciated |
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07/12/2007 04:18:57 PM · #11 |
Macro focus is a challenge. It may not be the distance issue. It may simply be what you are focusing on instead. The camera's autofocus system requires some contrast somewhere in the scene in order to achieve autofocus. You can demonstrate this by trying to have your camera focus on a white sheet of paper. If the AF system can't find any source of contrast in the image, it won't likely achieve an autofocus.
In my experience with macro photography, I have found that manual focus usually works best. Even if your camera will autofocus on the subject, it may not AF in the specific point where you want it to. Most macro photography is dealing with a VERY shallow depth of field also, so the point where you focus IS critical to the entire image.
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07/12/2007 04:40:37 PM · #12 |
Originally posted by edward80:
...it keeps giving me either a sequence of flashes... |
This happens when you're in one of those idiot modes. The flash pops up to help you the auto focus system. This means you don't have enough light for our auto focus system to get a lock on something to focus on. Also, if you're too close, your lens actually gets in the way of your pop-up flash.
Solution:
1. Get more light.
2. Get a better lens (bigger aparature).
3. Buy an external flash. External flashes project an IR beam of light that the auto focus sees and helps to lock a focus (just like your pulsing pop-up flash, but nicer).
Originally posted by edward80:
i currently do all the focusing in manual mode which is really depressing ( sometimes i get good shots but most of them are out of focus) |
I hope you're using a tripod to do your macro photography. When you start to focus down to macro distances, the DOF gets really shallow. A slight move will bring you out of focus. That would explain your frustration. You could get around this a little by setting your shutter in burst mode and just focus and fire away until you fill up your buffer. One of the shots might be in focus.
Or, just use a tripod.
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07/12/2007 08:40:10 PM · #13 |
| you could always try switching from AF-S to AF-C, at least then youll be able to shoot if the focus wont lock :-P |
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07/13/2007 02:19:59 AM · #14 |
Sounds like a low light issue.
Can you provide us examples of pics that are in and out of focus?
Can you also please let us know which lens you are shooting with?
You would be surprised how little light there is indoors. If you are shooting something and your focusing spot is on something without contrasty features, you will get all kinds of hunting around. Shooting with the kit lens indoors is a frequent cause of troubles. This will generate the 'sequence of flashes'.
Incidentally, the best macro lenses often have a bit more minimum distance from the subject than you might expect. |
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07/13/2007 04:45:05 AM · #15 |
Are you pressing the shutter release first half way in order to focus and after that push it all the way in order to shoot?
It sounds a little bit like you are pushing the button all the way and then gets surprised when the camera finally decides to actually take the picture. |
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07/13/2007 05:12:56 AM · #16 |
Definitely sounds like inability to focus due to low light. Put it on the P setting or widen the aperture. Increase the ISO. And feed your camera some carrots.
I think autofocus is useless for macros. I'm a compulsive manual focuser for everything except some landscapes. |
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07/13/2007 10:58:49 AM · #17 |
here is a couple of shots i took outdoors ,the 1st shot was done using manual focus, the 2nd "wannabe macro" shot was taken using the autofocus (1.5-2 meters,of course i was trying to zoom at the bee not the flower but the autofocus didn't help me out...Manual (1st pic)
//i2.photobucket.com/albums/y24/edward80/1-1.jpg?t=1184338299
Auto (2nd pic)
//i2.photobucket.com/albums/y24/edward80/2-1.jpg?t=1184338639
Message edited by Manic - please keep images under 500px and 30kb, or post links or thumbs instead. |
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07/13/2007 11:14:37 AM · #18 |
I think manual focus is the way to go for macros. I use autofocus to get in the ball park and then switch to manual.
Also, take several pictures of the same thing. It's quite normal to only get one really sharp one out of a bunch.
Make sure your shutter speed number is at least as high as your focal length number. Bump up your ISO to 200 or 400 if necessary to achieve this.
And using a good lens makes all the difference. |
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07/13/2007 11:23:12 AM · #19 |
| another thing thats effecting you is the fact that it's not the sharpest lens in the world unfortunatly. the lens is made as a zoom telephoto and just doubles as a macro. To get optimum results youd want to seperate the 2 and get yourself a true macro |
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07/13/2007 04:07:08 PM · #20 |
Oh yeah, second what  noisemaker said. I think the kit lens is mighty soft in many cases, and very hard to focus. If you don't have the big bucks to buy a real macro, the 50mm, 1.8 is a great cheap sharp lens and although not ideal for macros because you'll have to crop, you can get some nice detail. For examples see here, here, and here |
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07/13/2007 04:23:39 PM · #21 |
Originally posted by edward80:
am using a tamron 70-300/4-5.6 macro |
zoomed in that lens is only giving the camera a f/5.6 to use to focus. That's not a real big aperture if the light is low. I suspect this is your problem.
Cure: add more light or get a faster lens.
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07/13/2007 04:41:13 PM · #22 |
Do you have the AF point set in the middle when you take those shots?
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