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Old 25th August 2010, 15:05   #4831
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Originally Posted by tsk1979 View Post

350D has servo AF(continuous focus tracking on a moving object), are you sure 1000D does not have it?
1000D has 7 AF points and does have Servo AF.
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Old 25th August 2010, 15:21   #4832
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Originally Posted by tsk1979 View Post
350D has servo AF(continuous focus tracking on a moving object), are you sure 1000D does not have it?
.
Are you sure that 350D tracks the focus ? From what I know the shutter snaps in Servo AF on 1000D but if subject is moved the picture will be blurred in 350D and 1000D.

With Digic4 canon introduced tracking the focus called servo AE. googled on Servo AE and found the explanation of the feature in context of P&S.

Canon UK - Power, flexibility and stand-out style ? capture everything with the stunning new PowerShot SX210 IS
It reads
"Servo AF mode now includes Servo AE, tracking moving subjects and continuously correcting focus and exposure to ensure that pictures are correctly captured when the shutter button is pressed."

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Originally Posted by Abbas View Post
1000D has 7 AF points and does have Servo AF.
Please check if the manual says Servo AF with mention of for focus tracking or just Servo AF.

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Originally Posted by tsk1979 View Post

Focus accuracy is depending on AF module, not on the processor. Processor helps with the burst speed. Along with a fast processor, you also need a bigger buffer, and probably faster shutter mechanism.
Cameras sharing same AF module will have similar focus speed an accuracy.
For example 500D and 50D cross type focus points focus with same speed on lenses brighter than F2.8, even though their burst speeds are different.
50D and 500D have same processor ( Digic4) but burst rate differs. I think either it is artificially locked in software or there is some other bottleneck like slower CPU and bus clock , both XXD and XXXD uses same RAM as well.
The difference between 50D and 500D is in shutter mechanism 1/4000 max for 500D versus 1/8000 for 50D.

As per the information available in public domain the Focus tracking mechanism is feature of the Digic 4 processor of Canon. Also they have built face detection / motion detection in P&S range based on this capability.

Last edited by amitk26 : 25th August 2010 at 15:32.
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Old 25th August 2010, 15:25   #4833
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Coming back to the topic, if someone offers me 30k, I'd still pick up a 1000D and a couple of lenses than pick a 500D with one lens. I think I don't get technology much after all :(.
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Old 25th August 2010, 15:30   #4834
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Originally Posted by HellwratH View Post
Coming back to the topic, if someone offers me 30k, I'd still pick up a 1000D and a couple of lenses than pick a 500D with one lens. I think I don't get technology much after all :(.
Actually it was 500D ,1000D and 450D so I would still say 450D for same 30K ,With in 30 K it is not possible to buy any additional lens then a 50mm F1.8 lens with a 1000D.

Last edited by amitk26 : 25th August 2010 at 15:33.
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Old 25th August 2010, 15:32   #4835
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Originally Posted by HellwratH View Post
Coming back to the topic, if someone offers me 30k, I'd still pick up a 1000D and a couple of lenses than pick a 500D with one lens. I think I don't get technology much after all :(.
I second that

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Originally Posted by amitk26 View Post


Please check if the manual says Servo AF with mention of for focus tracking or just Servo AF.
Well it has 3 modes

1 One-shot AF
2 AI Focus AF
3 AI Servo AF
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Old 25th August 2010, 15:43   #4836
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Quote:
Originally Posted by amitk26 View Post
Are you sure that 350D tracks the focus ? From what I know the shutter snaps in Servo AF on 1000D but if subject is moved the picture will be blurred in 350D and 1000D.

With Digic4 canon introduced tracking the focus called servo AE. googled on Servo AE and found the explanation of the feature in context of P&S.

Canon UK - Power, flexibility and stand-out style ? capture everything with the stunning new PowerShot SX210 IS


Please check if the manual says Servo AF with mention of for focus tracking or just Servo AF.


50D and 500D have same processor ( Digic4) but burst rate differs. I think either it is artificially locked in software or there is some other bottleneck like slower CPU and bus clock , both XXD and XXXD uses same RAM as well.
The difference between 50D and 500D is in shutter mechanism 1/4000 max for 500D versus 1/8000 for 50D.

As per the information available in public domain the Focus tracking mechanism is feature of the Digic 4 processor of Canon. Also they have built face detection / motion detection in P&S range based on this capability.
Well the 1000D and 350D specs do say AI Servo AF, which basically means focus tracking. They also give maximum speed

Of course 450D AF module can focus faster.
As for limiting shutter speed, it also depends on the mechanical shutter, and there is obviously some limiting done in software, as well as buffer etc.,
As for face detection, again you are confusing. Servo AF means continuously varying the focus when subject where the center point rests. so lets say you have a car coming towards you, in one shot AF, you half press camera locks focus, and when you full press, the camera takes a picture, It is possible, that due to car moving, it will be out of focus. In AI servo, the camera is continuously focusing under the center point.
So even if you are moving the camera, its continuously focusing. It drains batteries though as AF mechanism is always active, not just on half press.

Now coming to face detection, I think I understand where your confusion is coming from.
There are two ways to focus in a DSLR with live view. You either use the focus points, which is phase detect. So if you are shooting a moving dog, as long as you keep the dog in the focus point of your choice, it will be in focus, but if the dog is not under the focus point of your choice, it won't be in focus.
With live view you have the choice of "Contrast detect" focus. Its slower, but its used in "tracking" which almost all current P&S have.
For example, my FZ35 remembers what I look like. when in potrait mode, somebody shoots a group photo, it recognizes the faces, and if I move around, the camera will move focus accordingly.
Now the fixed AF points cannot be moved around, but in contrast detect focus this is possible.

Now coming to action photography, no pro uses contrast detect due to its inherent slowness over phase detect AF. They move the camera with the subject always looking through the viewfinder and keeping center focus point on subject.

Example a photog shooting a footballer running. The camera continuously auto-focuses on the footballer, as soon as he is about kick, the pro will press his shutter button, and let loose 20 shots in 2 seconds.
In most scenarios when shooting a fast game, around 15-17 of these shots will be in focus
For the newspaper print, the photographer will use the best out of these.
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Old 25th August 2010, 15:45   #4837
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Originally Posted by amitk26 View Post
Actually it was 500D ,1000D and 450D so I would still say 450D for same 30K ,With in 30 K it is not possible to buy any additional lens then a 50mm F1.8 lens with a 1000D.
1000D+18-55 Non IS+55-250 or 1000D+18-55IS+50mmf1.8. That's what I'd be looking at for a beginner. Nothing like the a telephoto or a 1.8 lens to teach you DOF concepts.
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Old 25th August 2010, 15:51   #4838
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While we discussed sensors of various Canon Cams I found a table here doing sensor comparison, Check the DLA

Canon EOS Rebel T1i / 500D Digital SLR Camera Review

Also there is a image sample comparison tool available.

Canon EF 200mm f/2.0 L IS USM Lens - Canon EF 200mm f/2.0 L IS USM Lens Comparison - ISO 12233 Resolution Chart Results

Hope this will be useful for people buying new cams.
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Old 25th August 2010, 15:59   #4839
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I can list the reasons why I moved from D40 to D300. I happily used my D40 for more than 2.5 years without any hickup. I believe I can say that in that time I overpowered my D40.

1. AF - For birding the AF speed and 3 point AF is not at all par. Moving the camera right-left-top-bottom to get subject in focus was a normal practice. The AF brace area is quite big, it becomes real cumbersome to do Macro. Since the brace is big, super macro would end up with inaccuracies.

2. FPS- It did matter during birding. I missed many shots due to 2.5 fps.

3. No support for AF lenses- The MF is good for its purpose, but at times it may frustrate you when it is not required and u are forced to do MF.

4. Awry Metering- The metering in D40 is highly inaccurate. I realised that during the ranganthittu trip again. Under and over exposure in any scenario is not uncommon in any metering mode. What you want is not what you get.

5. The camera does not complement the size of big lenses like 200-400mm. Also for changing the setting u have to go thru menu. For landscpes it is ok, but for sports it is a real difficult thing. By that time I change metering my subject was gone.

6. ISO was unusable beyond 400. Missing ISO 100.

7. I knew I could do better provided I have a better cam, and thus the reason for D300.

8. WIth D300, I dont have to worry about high ISO, AF speed, fps and the focus points.

9. Its AF is fast like crazy and highly accurate. Metering blows me off in any scenario and any mode.

10. Added weight due to mag alloy gives a real nice grip. Buttons are very placed and customizable. It is very handy to change any setting in miliseconds.

Last edited by Speed Pujari : 25th August 2010 at 16:00.
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Old 25th August 2010, 16:03   #4840
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Originally Posted by amitk26 View Post
First what I mean by long exposure here in this case is 300 mm focal length with 1/30 or 1/60 shutter speed to compensate for low light.
There is something totally confusing here. You mean to say you use live-view to shoot birds and that too in a 1/30 or 1/60 shutter speed with a 300mm lens ? I really doubt if you can recognize the subject at all in that kind of set-up. May be something is missing.

I find a basic requirement of a shutter speed above the focal length (1/200 or more for a 200mm lens) for a decent shot of a bird sitting restless and a 1/1000 or more with the same 200mm lens for a bird in flight. If you are talking about low light, you should have your ISO at 800 or high to achieve a fair enough shutter speed. Gurus, I stand open to correction if I dont make sense, its purely from my own testing and learning in the last few months.

Here is an image I posted at image thread.
Its 200mm, 1/3000 at ISO 100, f/2.8, pattern metering on a cloudy day. PP is very minimal.
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This is with 400mm, 1/500 at ISO 400 at f/5.6, spot metering on a fairly lit day. Highly processed with extra sharpening etc. still its way below my 'decent' rating. I am sure it would have been a very sharp shot if the setting was 1/1000 or more.
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My point is, live-view becomes a real help at situations where you cant get an easy view through your view-finder like above head, below knee etc. also while doing real MACRO of flowers, bugs etc. I have never used it for a bird in move or static, because it just doesn't do any help. Focusing through a live-view is always slower in most cameras as far as I understand. Shooting a landscape using live-view is only a convenience part, not any difference from using the view-finder. Whatever scene it is, live-view is slow to focus, unless you are doing everything manual. I use manual for all macros and I dont find it annoying.
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Old 25th August 2010, 16:13   #4841
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Quote:
Originally Posted by Speed Pujari View Post
I can list the reasons why I moved from D40 to D300. I happily used my D40 for more than 2.5 years without any hickup. I believe I can say that in that time I overpowered my D40.

1. AF - For birding the AF speed and 3 point AF is not at all par. Moving the camera right-left-top-bottom to get subject in focus was a normal practice. The AF brace area is quite big, it becomes real cumbersome to do Macro. Since the brace is big, super macro would end up with inaccuracies.

2. FPS- It did matter during birding. I missed many shots due to 2.5 fps.

3. No support for AF lenses- The MF is good for its purpose, but at times it may frustrate you when it is not required and u are forced to do MF.

4. Awry Metering- The metering in D40 is highly inaccurate. I realised that during the ranganthittu trip again. Under and over exposure in any scenario is not uncommon in any metering mode. What you want is not what you get.

5. The camera does not complement the size of big lenses like 200-400mm. Also for changing the setting u have to go thru menu. For landscpes it is ok, but for sports it is a real difficult thing. By that time I change metering my subject was gone.

6. ISO was unusable beyond 400. Missing ISO 100.

7. I knew I could do better provided I have a better cam, and thus the reason for D300.

8. WIth D300, I dont have to worry about high ISO, AF speed, fps and the focus points.

9. Its AF is fast like crazy and highly accurate. Metering blows me off in any scenario and any mode.

10. Added weight due to mag alloy gives a real nice grip. Buttons are very placed and customizable. It is very handy to change any setting in miliseconds.
I totally respect such a detailed analysis and the reasons why you'd want to upgrade . Keyword being upgrade. Point is, most of us when we get into this field are not even aware of the stuff involved in it. It only makes sense to pick up something on the lower side to even assess if you'd still be interested in sticking to this hobby over a long period of time. It's always a heart burn to pick something up, realize that you are not utilizing it completely and then sell it for a much cheaper price. Not that I am complaining, but just doesn't make sense to me.
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Old 25th August 2010, 16:19   #4842
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Originally Posted by tsk1979 View Post
There are two ways to focus in a DSLR with live view. You either use the focus points, which is phase detect. So if you are shooting a moving dog, as long as you keep the dog in the focus point of your choice, it will be in focus, but if the dog is not under the focus point of your choice, it won't be in focus.
With live view you have the choice of "Contrast detect" focus. Its slower, but its used in "tracking" which almost all current P&S have.
Good explanation of contrast detect AF and phase detect AF
Incidentally I did some more reading on this to understand better after your post and found Nikon D90 only provides Contrast detect AF in live view mode and there is no phase detect AF in live view.

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Originally Posted by shajufx View Post
There is something totally confusing here. You mean to say you use live-view to shoot birds and that too in a 1/30 or 1/60 shutter speed with a 300mm lens ? I really doubt if you can recognize the subject at all in that kind of set-up. May be something is missing.
Why ?
Quote:
Originally Posted by shajufx View Post
I find a basic requirement of a shutter speed above the focal length (1/200 or more for a 200mm lens) for a decent shot of a bird sitting restless and a 1/1000 or more with the same 200mm lens for a bird in flight. If you are talking about low light, you should have your ISO at 800 or high to achieve a fair enough shutter speed.
You need shutter speed = 1/ focal length min to remove camera shake while you press button.
Will post a pic later after 6:40 at madiwala lake in winters even ISO1600 was kind of useless ( By the way in my cam up to ISO 3200 is useful and non grainy in normal conditions).
An alternative I found was to allow more light on sensor by slowing shutter as I can not open aperture more then 5.6 and use live view and tripod to reduce shake.

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Here is an image I posted at image thread.
both Your pics are in good light try shooting after sunset when only faint light is there.
Quote:
Originally Posted by shajufx View Post
Focusing through a live-view is always slower in most cameras as far as I understand. Shooting a landscape using live-view is only a convenience part, not any difference from using the view-finder. Whatever scene it is, live-view is slow to focus, unless you are doing everything manual. I use manual for all macros and I dont find it annoying.
I did not notice the focusing to be slow in live view. Yes it is about convince because I do not want to crouch in to view finder on my 4.5 feet el-chepo tripod.
Also I do not do photo-shoots very regularly like you post here, so may be slow focus is something which I may encounter later.

Last edited by amitk26 : 25th August 2010 at 16:22.
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Old 25th August 2010, 17:03   #4843
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..... try shooting after sunset when only faint light is there........I did not notice the focusing to be slow in live view.
I will try that, but a slower shutter speed through live-view will definitely give me an empty canvas for sure . Even panning requires decent lighting unless you are shooting moving cars with lights.

I have tested panning birds in decent light, but I was not aware of the higher ISO or negative exposure value leading to a higher shutter speed until May 2010 (still learning many basics), otherwise this shot would have been a real keeper for me. Sadly this is not to my satisfaction with 300mm, 1/200, f/5.6 at ISO-100, spot metering, fast panning. How I wish If it was shot at 1/400 or more.
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Old 25th August 2010, 22:40   #4844
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Default Which travel tripod ?

I am aware of the "golden 2" rule for tripods (Cheap, Light , Sturdy - choose any 2, you cant have all 3)

but still, I need to buy a tripod especially for travel (hiking, backpacking etc)
Following are the conditions
1. Should be able to support Canon 450D + 70-200 F4 L IS (maximum weight)
2. Should fit in backpack - folds down to around 15" - dont mind it being a bit heavier, as long as it folds down to small size.
3. Ball head to support above camera - lens combo.

Any recommendations?
My budget is around $100.
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Old 26th August 2010, 11:05   #4845
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The 60D is here...
Canon EOS 60D Hands-on Preview: 1. Introduction: Digital Photography Review

And so are these lenses,
Canon (8-15) - Canon releases EF 8-15mm f/4 L USM fisheye zoom lens: Digital Photography Review

Canon (70-300L IS) - Canon launches EF 70-300mm f/4-5.6L IS USM: Digital Photography Review

Canon 300mm and 400mm 2.8 L lenses-
Canon EF 300mm f/2.8 L IS II USM and EF 400mm f/2.8L IS II USM: Digital Photography Review

Canon 500mm and 600mm L lenses -
Canon develops 500mm F/4L IS II USM and the 600mm F/4L IS II USM lenses : Digital Photography Review

Canon 1.4x and 2x III extenders -
Canon announces EF Extender 1.4x III and EF Extender 2x III: Digital Photography Review

Don't know about the pricing of 70-300, but if the IQ is nice, that'll be the next lens in my kit.
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