Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Canon EOS dSLR

Reply
 
Thread Tools Search this Thread
Old Sep 10, 2007, 2:10 PM   #41
Member
 
Join Date: Jun 2004
Posts: 99
Default

I'm almost sorry that I started this. But I was "scared" into purchasing filers by an Adorama rep that called me after I ordered two lenses from their site. I agreed and they added the filters to my order. I used them religiously and they did cause me problems.

I just wanted to make the OP aware that there are pros and cons to filters, and just about everything, and that he should do his homework based on his shooting conditions.

Some filters are very advantageous,others not so much.
Proxes is offline   Reply With Quote
Old Sep 10, 2007, 2:37 PM   #42
Moderator
 
Join Date: Aug 2004
Posts: 8,529
Default

As I said earlier, whether or not to use a UV filter is an on-going debate. I doubt very much either side is going to convert someone to their way of thinking.

Some people never use them and experience no problems and don't lose sleep over not having them.

Others use them and experience no problems with reduction in image quality.

I've gone both routes. When I used the filters I used high quality filters (Hoya Pro in my case, but B&W are also highly recommended). And I could not detect any image degradation.

But I will also say I have some 4 year old lenses and I've had no problems with lens coatings being destroyed by my occasional cleanings. I regularly shoot sports on soccer fields and baseball diamonds and have experienced no lens damage from those conditions and no filter. The lens hoods keep the majority of dust from the lens and a rocket blower takes care of the rest. I've gone through about 50,000 shots in the last 4 years and probably clean a given lens with solution about 2 times a year. But I'm also not on a beach a lot like aladyforty - if I was I would probably still use filters.

So, either way will work, IMO. If you are going to use them though it absolutely makes sense to use high quality filters - which means you're going to pay a pretty penny. It makes no sense to have a nice lens and put a $10 piece of glass on the front end.

In the end I wouldn't stress over this tidbit. It's been blown up much more than it needs to be.
JohnG is offline   Reply With Quote
Old Sep 10, 2007, 3:12 PM   #43
Senior Member
 
Cyberf828's Avatar
 
Join Date: Sep 2006
Posts: 659
Default

Okay what round are we on?


Cyberf828 is offline   Reply With Quote
Old Sep 10, 2007, 5:41 PM   #44
Senior Member
 
nickphoto123's Avatar
 
Join Date: Aug 2004
Posts: 1,356
Default

Round?? I have square filters too!!!

I find this thread very interesting and educational.

Putting aside someone's " :blah:" to me, and his calling my statements 'rubbish', and 'silly Hype' ( all from the same poster ) we at Steve's Digicams are most civil indeed.

A vignetting UV filter is the wrong UV filter to buy.Apoor buying decision.

Refering to DXO's distortion correction, I am talking about subject lines and not vignetting.

I believe we can all agree that this discussion will lead ALL of us to be more careful when handlinga lens, especially asit relates to its coating.

Nicholas
nickphoto123 is offline   Reply With Quote
Old Sep 10, 2007, 8:26 PM   #45
Member
 
Join Date: Sep 2007
Posts: 31
Default

More on topic, I assume this is right: when in low-light conditions, a too-fast shutter speed will result in a completely black picture, correct? This is as a result of not letting enough light in quickly enough?
WilliamG is offline   Reply With Quote
Old Sep 10, 2007, 10:29 PM   #46
Senior Member
 
nickphoto123's Avatar
 
Join Date: Aug 2004
Posts: 1,356
Default

More on topic?? Now, that's funny.

Nicholas
nickphoto123 is offline   Reply With Quote
Old Sep 10, 2007, 10:54 PM   #47
Member
 
Join Date: Sep 2007
Posts: 31
Default

nickphoto123 wrote:
Quote:
More on topic?? Now, that's funny.

Nicholas
Good....grief.

Thanks for the helpful reply...:O
WilliamG is offline   Reply With Quote
Old Sep 11, 2007, 12:26 AM   #48
Member
 
Join Date: Jun 2004
Posts: 99
Default

WilliamG wrote:
Quote:
More on topic, I assume this is right: when in low-light conditions, a too-fast shutter speed will result in a completely black picture, correct? This is as a result of not letting enough light in quickly enough?
Correct; but it's the result of not letting enough light in *long enough*. The faster the shutter the less time it's open to let light hit the sensor.

There's two main things that you can use on your camera to control the amount of light that it lets in. First is the shutter. The shutter controls the amount of time the light hits the sensor or film. Second is the aperture. Aperture is a number that represents the diameter entrance pupil. The smaller the number the wider the pupil or hole, so it lets more light in. The larger the number the smaller the hole and the less light it lets in. It might seem backwards but that's the way it work.

The other thing that affects exposure is the ISO setting. The higher the ISO the more sensitive the sensor or film is to light. That is to say less light is needed to get the proper exposure, but at the cost of more noise in the image.

So if you're shooting in very low light use a higher ISO, like 800 or 1600 if you need. You don't want to hand hold a camera below a shutter speed of 1/60, the images will be blurry. Also open up your aperture to the smallest number and that will letas much light in as possible. How wide the aperture can go depends on the lens. The better the lens the lower the number, e.g., 1.4, 2.8, etc.

Use the exposure level indicator in your view finder to help meter out the proper exposure.


Proxes is offline   Reply With Quote
Old Sep 11, 2007, 5:52 AM   #49
Senior Member
 
nickphoto123's Avatar
 
Join Date: Aug 2004
Posts: 1,356
Default

WilliamG wrote:
Quote:
nickphoto123 wrote:
Quote:
More on topic?? Now, that's funny.

Nicholas
Good....grief.

Thanks for the helpful reply...:O
I already gave my answer your question previously in this thread:

"3) Shoot only on Aperture priority and/or Shutter priority for the same month as in #1. This will teach you how to control the particular amount of light hitting your sensor, and controllingthe amount of time the sensor is exposed to light. This is your 'Light Paint Bucket'. You capture images by painting them with light. This will teach you how to handle the paint bucket and the brush. I am stressing controlling the light as it hits your sensor at this point, not the 'Quality' of it.

During this time you will note your exposures, mm, etc. ( much easier than EXIF info on an image by image basis ) via pen & paper. Do not erase images in camera. ReviewALL your images, with your notes in hand,on your CRT/LCD and observe the effects your settings have on your images.

Do this for a month and you will be in good position to move wisely forward in the fantastic endeavor known as photography".
-----------------------------------

Not "Good grief"...but... Good Answer, IMHO.

-----------------------------------

WilliamG wrote:

"More on topic, I assume this is right: when in low-light conditions, a too-fast shutter speed will result in a completely black picture, correct? This is as a result of not letting enough light in quickly enough?"

No.....Your assumptionis not correct.

Pictures that appear 'completely dark' actually have alot of image data, most times the image is useless, but it is amazing how much Digital Capture can record, even with an incorrect exposure. Images are 'completely black' when shot with the lens cap on ( usually ).

"A too-fast shutter speed" has no meaning unless you also mention the Aperture and ISO rating as Proxes pointed out.

That is why I suggested a good way to learn is my "#3" above.

As a student, you should not 'assume' anything. You should start the learning process. When you 'assume' at this stage of learning you are also 'assuming' you know which questions to ask for clarification of a topic.

Regards,

Nicholas
nickphoto123 is offline   Reply With Quote
Old Sep 11, 2007, 7:58 AM   #50
Moderator
 
Join Date: Aug 2004
Posts: 8,529
Default

William,

Ashas been mentionedyour photo is dark because it is way under exposed. Aperture (controls how much light gets in), shutter speed (controls how long light is let in)and ISO (how sensitive the medium is to light)all work together to determine exposure. Here is some info:

ISO stops: 100, 200, 400, 800, 1600, 3200

F-stops (indication of aperture - not technically but it's how we speak about aperture: 1.0, 1.4, 2.0, 2.8, 4.0, 5.6, 8.0,11.0, 16.0, 22.0, 32.0

Shutter speeds (each stop is a doubling of speed): 1/15, 1/30, 1/60, 1/125, 1/250, 1/500, 1/1000, 1/2000, 1/4000

The same exposre can be obtained by many combinations of these three.

Let's say an image is properly exposed at f8, 1/500 and ISO 400

F5.6, 1/1000 ISO 400 is the same exposure

f11, 1/250 ISO 400 is the same exposure

f8, 1/1000, ISO 800 is the same exposure

f8 1/125, ISO 100 is the same exposure

f5.6, 1/2000, ISO 800 is the same exposure

So, you can correct underexposure by changing any or all 3 of the above. But each has it's downside: increasing aperture (lower f-stop) leads to shallower depth of field, higher ISOs lead to more 'noise' in the photo and slower shutter speeds lead to camera shake or motion blur.

Alsothere are limitations: a lens with a max aperture of 5.6 can't open up to 2.8 (which is a reason why TV mode is a dangerous mode to use in low light situations - it can more easily lead to underexposed images if you don't recognize you've maxed out the aperture and still don't have proper exposure). A camera capable of only ISO 1600 can't go to 6400.

And, of course, there is another solution to underexposure - add more light (flash, strobes, sunlight, lamp, etc).


JohnG is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 7:32 AM.