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gman1987 Jan 9, 2010 11:03 AM

Never ending questions - I have questions
 
I just got my xsi with the 18-55 kit lens and the 55-200 lens. I new to photography and am learning to use the camera. I know I will have a lot of questions so I would create one thread and just ask my questions here instead of clogging the board with new threads with all my questions.

First question.
When i shoot in sports mode inside my images are blurry but when I'm outside (sunny day) they seem fine. I assume this has something to do with the aperture. Is that right? I'm not sure what the shutter speed is in sports mode but I assume it's fast since t needs to stop action.

Hards80 Jan 9, 2010 11:13 AM

disclaimer- i never use the scene modes, and have never set my camera to sports mode, ever.

my guess is sports mode sets the aperture as open as possible in order to get the fastest shutter speeds it can. however, the kit lens does not offer a fast (open) max aperture, so the mode is constrained by this, therefore it is not able to get fast enough shutter speeds to prevent camera shake despite its best attempts.

shoturtle Jan 9, 2010 12:12 PM

The imagine is blur, you will need to pan your shot with your object as it is moving. That way only the background is blur and the object still in focus. If you want to freeze the shoot. I would use Tv and set it to say 1/200 and it will freeze everything. I do not use the scene modes either.

check out the youtube workshop on action shots at www.dslrtips.com It can be helpful

gman1987 Jan 9, 2010 3:23 PM

Thanks, That was, I'm sure, the first of many questions. I know I will have more as I read and shoot more.

Mark1616 Jan 9, 2010 5:34 PM

Quote:

Originally Posted by shoturtle (Post 1037350)
The imagine is blur, you will need to pan your shot with your object as it is moving. That way only the background is blur and the object still in focus. If you want to freeze the shoot. I would use Tv and set it to say 1/200 and it will freeze everything. I do not use the scene modes either.

check out the youtube workshop on action shots at www.dslrtips.com It can be helpful

For shooting sports Tv is not the way to go if you are trying to freeze action, it is only really used if you want a slower then maximum shutter speed, such as when panning to get blur. This is an example when shooting in Tv, I was set to 1/60s I believe.

http://www.photographysmith.co.uk/mo...g_4020_std.jpg

So why is Tv no good for trying to get a maximum shutter speed? When using Tv you can easily get under exposed photos as you can select a setting too high for the available light so no matter what the camera tries it will still be dark. With a normal lens 1/200s will most likely be very under exposed.

For indoor sports you want to use Av or preferably Manual and set everything correctly so the camera doesn't get confused by dark or light objects in the background or by dark or light player kits. Using either Av or M you will want to have the aperture as wide as possible (small f number) and get the ISO right up to make the sensor as sensitive as possible.

Back to the original question, the reason that indoor shots with sports mode are blurring are that the ISO is probably not high enough and you are limited by the lenses you have. For shooting indoor sports you want to have lenses that are f2.8 or brighter. In poor gyms I will use an f1.8 lens.

http://www.photographysmith.co.uk/forum/basketball5.jpg

shoturtle Jan 9, 2010 6:11 PM

Opp's I missed the indoor part of the question. Though you were blurring outdoors. Sorry about that.

gman1987 Jan 10, 2010 8:09 AM

Thanks. I was just shooting my kids jumping up and down to see how the camera would do. When I actually do start shooting sports it will be outside at the ballpark. Does the above still hold true for outside?

Mark1616 Jan 10, 2010 8:11 AM

Any situation where you want to maximise shutter speed no matter the location you want to use Av or M and have the aperture as wide as possible (small f number). If shutter speed is too slow then increase the ISO, if you find you are getting a lot over 1/1000s which is a good place to be then you can bring the ISO down to reduce image noise.

spy Jan 11, 2010 9:55 AM

Quote:

Originally Posted by gman1987 (Post 1037318)
First question.
When i shoot in sports mode inside my images are blurry but when I'm outside (sunny day) they seem fine. I assume this has something to do with the aperture. Is that right?...

Welcome gman1987 and even though your just getting into this photography thing, I hope you enjoy every moment of it. You'll get a lot of great advice here so ask away.....

I would like to add my two cents to your question as well. I too never use the scene modes and assume they would be too confusingly auto for me. When you accept "auto" as a function, you think whatever the camera decides will be the best This is not always true. When you learn your camera and a couple basic photography principles and put yourself in the 'driver's seat', your photos will be exactly as you want them or close anyway. With some minor photoshoping and tweeking here and there is all you'll need to complete the image.

There are many principles in shooting photography but you only need to know a couple to get a good grip on starting. First principle is using the available light that's there. "Shutter speed" isn't just aperture. It's only one element of it. Your inside shot was blurry as apposed to outside because of the extra light all around not just because of your aperture setting.

As Mark mentioned above wide open aperture AND ISO's work together in obtaining the shutter speed your after. One thing however with a wide open aperture (small #) is that your area of focus or what is sharp is hampered by the "Depth of Field" (DOF). If you can only shoot an aperture with your lenses starting wide open at 3 or 3.5 zoomed all the way out, you may not want this look and find yourself zooming in somewhat which will change your aperture closer to 5.6. Your shutter will slow down here so you will then boost your ISO's to compensate.

You will also need to have a good eye on your focus point when you take your shot. Because everything in front and behind your focus point will be blurry due to DOF so if your capturing your kids jumping around your focus point should be their faces and more precisely, their eyes for the ideal shot.

One more point about wide open apertures is that images shot at this farthest range will turn out 'soft' so when I shoot sports with my 2.8 lenses, I will adjust to 3.2 or 3.5 instead so I can have a sharper image. Also because of 'noise' issues with the higher ISO's, I use Noiseware Pro to clean all that up.

One more point to make because your just getting into photography, it is my opinion that the image straight out of the camera was never meant to be the complete image. Because your now dealing with pixels (buckets of information) the image is just a capture of "information", a basis from which to work from in photoshop or other to complete the image.

Sorry for the writing of this book but do hope this helped somewhat.

Kevin
www.poetryofmotion.com

JohnG Jan 11, 2010 10:34 AM

So,

Trying to tie things up nicely here - why were the shots of your kids jumping too blury? 2 reasons - the aperture your lens had available and the ISO your xsi uses in sports mode (400) were not capable of giving you fast enough shutter speeds to stop the action. So it was both a lens problem AND and ISO problem. The ISO problem was caused by how sports mode works with the xsi. It sets the ISO to 400 (if I'm not mistaken) and doesn't allow it to change. Even at ISO 1600 you probably woulnd't be able to freeze the motion without using a flash. Mark & Kevin gave you some great advice but I wanted to circle back around to your question again.

If you want to mimick sports mode but get past the ISO 400 issue, then do the following:
  1. Set camera to aperture priority. Set aperture value to widest value (lowest f-stop) your lens is capable of.
  2. Set focus mode to AI-Servo
  3. Set frame rate to burst
  4. Adjust ISO to get necessary shutter speeds - 400 is a good start outdoors, but indoors you'll likely need 1600.
  5. Additionally I suggest you select center focus point only rather than allowing the camera to use all points. Using all points can have the unintended consequence of the camera switching focus to some other object in the photo. Using center point means you the photographer have to be more careful to keep that point on your subject BUT at least you take away the notion of the camera switching the focus.
In the end there is a lot more to shooting action. But the above 5 steps are simple enough to get you started - IF there is enough light for what you wan to shoot. That may not be the case. In my living room at night there's no way ISO 1600 and f5.6 is going to be able to capture my son jumping. Just not going to have fast enough shutter speeds. Then I need to use a flash to freeze the motion.

gman1987 Jan 11, 2010 10:41 AM

Thanks guys. This really helps. I'm taking a trip to the mountains this weekend and hopefully will get a chance to practice on some landscapes. I know I will have many more questions as I start using it more.

gman1987 Jan 12, 2010 1:08 PM

Ok Next question.
Someone mentioned not to bother with a uv filter but to look at neutral density or polorized filters. Are there different types? Is one ND or polorized filter as good as the next? If I only had one what would be the one to get? I saw a circular polorized and uv filter kit in Walmart for $20. Would these be decent filters or are good filters expensive as well? Would the uv filter be useful as another means of protecting the lens and can you use the lens hood with a filter? Not sure I need these yet especially if significant $$ is involved. The wife is still getting over the sticker shock from the camera and bag. :D

TCav Jan 12, 2010 1:22 PM

Neutral Density filters are to reduce the amount of light that enters the lens without decreasing the aperture, or when reducing the aperture and/or reducing the exposure time isn't enough. They are available in 1, 2, or 3 stop densities. There are also graduated neutral density filters for when you want to dim the light in one portion of the frame (like the sky) but not another (like the ground.)

Polarizing filters are for reducing glare and will also enhance colors.

If you only went with one filter, I suggest you get a Circular Polarizing Filter. It's more useful in more conventional situations than a neutral density filter.

And don't waste your money on cheap filters. Tiffen would be the minimum filter I'd recomments. Hoya, B+W and Heliopan are better and worth the extra money. A cheap filter can noticeably reduce image quality and induce flare.

For more info, see http://en.wikipedia.org/wiki/Photographic_filter

JohnG Jan 12, 2010 1:23 PM

OK, first and foremost - be careful whenever someone tells you you NEED a piece of gear without explaining WHY. Having said that, let's talk about the 3 filters you mentioned and what they each do:

UV filter: primary purpopse was to block UV light - no benefit whatsoever with the coated lenses in todays DSLRs. So, what UV filters are used for is to "protect the front lens element". Feel free to do some searches here and elsewhere. Lots of posts on the subject - some say it's good piece of mind, others say it offers no real protection and possibly degrades image quality or produces flare. Do some searches to see the pros/cons. My personal preference is to use lens hoods. I no longer use protective filters - but others do. search here and you'll see the arguments for/against.

Polarizing Filter: First, make sure it's "circular" and not linear. They both do essentially the same thing but in different ways and some DSLRs have issues with linear polarizers. If you own a pair of polarized sunglasses you can see the affect they have. First, they do act as suglasses - they cut down by almost 2 stops the amount of light geting in. Their biggest affect is in two areas: landscape where they can make the sky a deeper blue and provide more contrast with clouds. The CP is actually two pieces of glass one fixes to your lens and the other rotates. Rotating the second one changes the intensity of the affect.

The second benefit is a CP will cut down on reflections - so if you are shooting through glass or shooting cars or the like - the CP will help reduce the reflection you see in those objects.

A ND (Neutral Density) filter - this is like having sunglasses over PART of the image. Its a filter with one side darker than the other. They come in types that have a hard line difference or a graduated difference. And you can buy them in different strengths. They are primarily used for landscape work - imagine you're in a stream bed with trees all around but sky still visible. The sky is MUCH MUCH lighter than the scene down at the stream bed. A ND filter can be used to darken the light from the sky portion of the image. With the HDR technology of today this same affect can be achieved via software. The challenge with ND filters is they have a static affect - i.e. a 1 stop or 2 stop ND. So having just one filter may be good in one instance but not in another.

IMO, NONE of these are NEED TO HAVE items. Between the CP and the ND, the CP affects cannot be achieved as well via software so it's a more useful filter - but certainly a NICE TO HAVE, not a need to have.

Hards80 Jan 12, 2010 1:47 PM

i agree that none of them are a need to have item.

UV - i dont use them, they degrade image quality, i use a hood for protection

CP- I do use these from time to time, the reflection cutting effect can be nice in certain circumstances like water etc. And they can deepen the blue of a sky, but really that can be done in post-process as well.

Neutral Density - a regular Neutral Density is a uniform filter that reduces the amount of light coming in. this is useful because it can allow you to have longer exposures for when you want to smooth water, etc. this is a very nice filter if you do any kind of landscapes with water you want to smooth. a Graduated Neutral Density has a dark upper part and a clear bottom part, this allows you to properly expose a bright sky on dark foreground, this is useful in landscapes, but can be replicated by using HDR, or simply taking 2 exposures (1 of sky, 1 of land) and combining via layers.

so 2 filters cannot be replicated in post-process. certain aspects of a circular polarizer, and a standard neutral density. however, the neutral density is only useful if you want to smooth water with a long exposure on a tripod. and the circular polarizers main effect (dark blue skies) can be replicated in post-process now-days.

so really, none are really needed, but can be nice in CERTAIN instances.

gman1987 Jan 12, 2010 1:55 PM

Thanks, I'll probably forego the the filters for now and just concentrate on learning to shoot with what I have.

griffina6 Jan 12, 2010 1:57 PM

Quote:

Originally Posted by JohnG (Post 1038630)
OK, first and foremost - be careful whenever someone tells you you NEED a piece of gear without explaining WHY. Having said that, let's talk about the 3 filters you mentioned and what they each do:

Thanks John for the explanations.

As another new photographer I'll share my story...

When I first started buying lenses and right on the same web page was the recommended accessories I figured I had to get a UV filter for every lens I bought. My thoughts was to use it to protect my large investment. So for the first three that is what I did.

However, I have since come to agree that lens hoods are the way to go if your lens has one. Initially at night with the 50mm and 85mm I was getting a weird green spot on some images until I realized it was caused by the UV filter.

For the 70-200mm - I love the lens hood and use it all the time indoors and out. When I store it I do place the UV filter on it but the only time I shoot with it is at motocross tracks to protect the lens from flying rocks and dirt. I have seen motocross pics where a Circular filter was used and I may try that someday.

Andy

shoturtle Jan 12, 2010 2:34 PM

If you are going to shoot someplace where sea-spray, sand or dust is most likely, you may want a clear filter, or a haze 1 filter for protection. When out of the those environment I would remove the filters.

Mark1616 Jan 12, 2010 2:39 PM

For example I keep a filter on my main lens for general use but for weddings/studio shoots etc it comes off so I don't lose any quality. That is the only lens I have a filter on as it is my main one for moving around with.

gman1987 Jan 13, 2010 8:42 PM

Can some one explain depth of field to me? I'm reading about the AV mode and it says it is good for depth of field and action shots with the largest aperture. I guess I'm having trouble wrapping my brain around how the same setting do both. It would seem that the TV mode would be good for sports but i know someone here said they would only use AV and manual. If this is to big a subject to tackle maybe a link to a good discussion? Thanks

Mark1616 Jan 14, 2010 5:43 AM

This will give you a lot of information, it is quite technical but everything is there http://toothwalker.org/optics/dof.html

Going onto the other question about using Av or M mode, that is probably my advice.

It is a very common mistake to think that shooting Tv would be good for sport as you can set a fast shutter speed (this is assuming we are talking about freezing action, not creating motion blur). The problem is that in doing this you can easily set something that is too fast for the available light so everything will be under exposed. Or initially things are exposed OK then the light reduces and then you are again in the under exposed situation.

Another element of shooting the majority of sports is you want a shallow depth of field. If you are shooting Tv and there is a lot of light then the aperture will shut down increasing your dof which isn't desired. So there are 2 instant problems with Tv.

If we now look at AV you are going to set the widest aperture (low f number) which will ensure you are getting the most light into the camera thus allowing fastest shutter speed along with correct exposure and also the narrowest dof so you isolate your subject. If the light increases you get a faster shutter speed so you still get a good exposure, if it decreases you then would have a lower shutter speed but still exposed well. You just need to ensure you have set an ISO setting that allows you to obtain a good shutter speed.

Here is an example of freezing the action and also how the shallow dof helps get rid of a nasty background.

http://www.photographysmith.co.uk//f...ockey2008b.jpg

A time when you would want to use Tv in sports shooting is when you want to create a lower shutter speed so you can bring some motion blur into the equation. For example shooting vehicles this is often desired.

Here is an example of using Tv and shooting at 1/60s to get the motion blur (this shot was just off of the start line so not a huge amount of speed at this point so blur is not extreme).

http://www.photographysmith.co.uk/mo...g_4020_std.jpg

Going on from Av and Tv if you are able then shooting in M is better as you are not letting the camera guess the exposure. For example if something you are shooting is very light the camera will under expose a little as it trys to darken things up and if it is a dark subject it will over expose. This is why you see nearly everyone posting aircraft shots has them under exposed as the sky messes up the metering.

gman1987 Jan 14, 2010 7:36 AM

So its the aperture that determines the dof? The wider the aperture (lower number) the shallower the dof and the more narrow the aperture (higher number) the deeper he dof is that correct? So to shoot a pic with the subject and background in clear focus you need to have a smaller aperture and offset that with a faster shutter speed and or higher iso (depending on light)? I'll try and l read the link you provided if I get a couple minutes at work today.
Thanks

Mark1616 Jan 14, 2010 7:45 AM

Quote:

Originally Posted by gman1987 (Post 1039386)
So to shoot a pic with the subject and background in clear focus you need to have a smaller aperture and offset that with a faster shutter speed and or higher iso (depending on light)? I'll try and l read the link you provided if I get a couple minutes at work today.
Thanks

Almost but you have a slower shutter speed not faster to get the right exposure.

To make exposure brighter you decrease shutter speed, increase ISO or use a wider (smaller f number) aperture.

To make exposure darker you increase shutter speed, decrease ISO or use a narrower aperture (bigger f number).

If you make a change to one element and want the exposure to be the same you need to adjust one or both of the other variables.


Quote:

Originally Posted by gman1987 (Post 1039386)
So its the aperture that determines the dof? The wider the aperture (lower number) the shallower the dof and the more narrow the aperture (higher number) the deeper he dof is that correct?

Yes if you don't change other criteria. There are two other main variables which are focal length and distance to subject.

Take a look at http://www.dofmaster.com/dofjs.html and play with the settings to see the changes.

JohnG Jan 14, 2010 7:59 AM

Quote:

Originally Posted by gman1987 (Post 1039386)
So its the aperture that determines the dof?...So to shoot a pic with the subject and background in clear focus you need to have a smaller aperture...

That's part of it. Focal length also makes a difference as does distance from you to the focal point (i.e. the point in space you're focusing on). For example, 400mm f5.6 at 20 feet has shallower dof than 35mm f2.0 at 20 feet - even though the 35mm shot was taken at a wider aperture.
In addition to mark's link, here's a calculater you can play with to see how DOF changes when you vary focal length, distance, aperture:
http://www.dofmaster.com/dofjs.html


Also - another important point - you talked about your subject and background both being in focus. That also depends on how close your subject is to the background. If your subject is in front of a wall and the wall is 5 feet behind them they're both in decent focus even with only a few feet of DOF. Now, if your subject is 40 feet in front of the wall, even with the same DOF value suddenly the background is no longer in focus. So whether the background is in focus or not is partly controlled by DOF but also controlled by how close the subject and background are to each other.

JohnG Jan 14, 2010 8:00 AM

OK I stop typing for a minute and Mark beats me to it :)

Mark1616 Jan 14, 2010 8:09 AM

Quote:

Originally Posted by JohnG (Post 1039395)
OK I stop typing for a minute and Mark beats me to it :)

I hate it when that happens LOL.

Mark1616 Jan 14, 2010 8:10 AM

And that must have been nearer 15 minutes :p

gman1987 Jan 14, 2010 11:37 AM

My brain hurts and I'm just getting started.

Mark1616 Jan 14, 2010 11:42 AM

Don't try to do too much at once, also when you start playing and tyring things out it will make more sense.

gman1987 Jan 14, 2010 1:41 PM

I've been doing more reading than taking pics because by the time I get home I would have to use a flash and I don't know but I suspect that just complicates things more. How much will using a flash change what we are talking about her?

JohnG Jan 14, 2010 1:45 PM

Flash does not affect depth of field or subject isolation. BUT, it is another variable and when playing around with flash you can get inconsistent results (sometimes under exposed, sometimes overexposed) which can be somewhat frustrating.

gman1987 Jan 19, 2010 3:05 PM

How much does the lens effect the depth of field? Using my kit lens will I be able to manipulate the dof like a higher end lens? I took a few pictures this weekend but didn't see a lot of differenc in the dof from the lowest f# to the higher numbers I used. Is this because my lens only goes to F/3.5?

Hards80 Jan 19, 2010 3:08 PM

also, i am assuming since you said 3.5, you are shooting it at its lowest focal length (18mm). and a short focal length will have a larger dof anyways, especially on a crop body (more dof from smaller sensor), so at 18mm you are not going to have any shallow dof really at 18mm at 3.5 anyways, especially if you are any measurable distance away.

the amount of depth of field will be influence not only by the aperture, but also the focal length, distance from subject, and sensor size.

gman1987 Jan 19, 2010 3:16 PM

Quote:

Originally Posted by Hards80 (Post 1041937)
also, i am assuming since you said 3.5, you are shooting it at its lowest focal length (18mm). and a short focal length will have a larger dof anyways, especially on a crop body (more dof from smaller sensor), so at 18mm you are not going to have any shallow dof really at 18mm at 3.5 anyways, especially if you are any measurable distance away.

the amount of depth of field will be influence not only by the aperture, but also the focal length, distance from subject, and sensor size.


Let me get this right. the 3.5 is only achieved at the 18mm focal length? Does that mean the 5.6 is the widest aperture at 55mm?

shoturtle Jan 19, 2010 3:18 PM

yes on the kit lens 5.6 is the widest it gets at 55mm

gman1987 Jan 24, 2010 6:35 PM

I was looking around craigslist and found a Canon 50mm 1.8 (11) for sale for $50. A few questions. Is this what is considered a prime lens? What would you use this for? Even though I haven't figured out how to use the lens I have, would this lens at this price be a good idea anyway? I'm just thinking that if it is something I will eventually use maybe I should jump on it. Thoughts?

shoturtle Jan 24, 2010 6:55 PM

Yes it is a prime lens, and the plastic fantastic is a very good one, ant 50 bucks is pretty good for it. I sells for about 100 new. You can use it for portraits, low light, and even macro shooting if you set it to mf. This lens will be able to give you a nice bokem effect when you set it to the wider apertures. It is a great little lens.


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