Question about Canon 75-300mm f/4-5.6 III USM EF Lens

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Stableizer On or Off

How do I know the Stablizer is on when I'm shooting?
Where should the Switch be on the Lens

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Re: Stableizer On or Off

Should be on the left side, near where it mounts on the camera.

Posted on Dec 06, 2007

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My 100-400 mm EF canon takes too long to auto focus.I like to take pictures of flying birds and i get alot of blurred pictures even at a shutter speed of 1/3200sec. I use the #2 position on the stabilzer...

Manually pre-focus to the distance you'd expect then the auto focus won't have far to move/lock on. Only turn the IS off if you are using a tripod. The auto focus works by detecting a difference in contrast so if the conditions are not compatible i.e a BG the same as the subject it will 'hunt and peck'.

Jan 26, 2014 | Canon EF 100-400mm f/4.5-5.6 IS USM Lens

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Sigma 18-250mm F3.5-6.3 DC (OS)* MACRO HSM is shooting grainy pictures on Nikon D5000

My guess is the camera tries to go to a high ISO. Easy to check in NXview. Switch of the OS, put the camera on a tripod and use a low iso, to see if you can make pictures without grain (digital noise)
I know that is not an option for you in the field, but just to see the lens and your camera can make beautiful pictures.
Newer camera's can work with higher ISO, without seeing digital noise. Buy a second hand (new in the Xmas sales) D7000. You can easy shoot till ISO 3200 and hardly see any noise.

Nov 08, 2013 | Sigma Camera Lenses

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I did not get any instructions with my Opteka. Have tried to take photos with it. But they came out all blank. I used a tripod. Would like to know where I can down load instructions. Certainly not as good...

You did not provide enough information to determine what your problem is. For example, were the pictures all light or all dark. Knowing this lens, I will assume that they were all dark. So...

1) This is a very, very slow manual-focus lens. It will not auto focus. It must be manually focused very precisely because it has virtually no depth of field.
2) Depending on your camera, your internal light meter may not work. On my camera (Nikon D-90), it does. If it does not on yours and I suspect that may be your problem, you're going to have to shoot everything manually, i.e. setting the shutter speed and lens opening yourself. You can use your internal light meter to help you get started by taking your light reading before you install the lens...preferably using the aperture only setting where you set the aperture at f8 which I think is the speed of the Opteka and let the camera set the shutter speed. Make a note of the shutter speed then attach the Opteka to the camera and mount the lens on a tripod with the camera attached.
Then set your camera mode to manual and set the aperture to match the lens (f8, I think). Set the shutter speed at the speed you noted earlier. Shoot a picture using a remote shutter release or the self timer. This lens is so slow that unless you're in exceptionally bright conditions you will get fuzzy pictures due to camera movement at full zoom of 1200m and above if you're using the 2X doubler. I would start shooting at minimum zoom of 650 without the 2X doubler. Shoot a picture. and check the result.

You should have an image but it may be too light or too dark.

If its too light you'll need to increase the shutter speed or stop down the aperture to, say, f11...or both. Make the adjustment and shoot another picture. Remember that if you increase the aperture, you increase your depth of field, making focus less critical. If you increase the shutter speed you make camera or subject movement less critical.

If it's too dark, you can only increase the shutter speed because you can't open the lens any wider than f8. Make the adjustment and shoot the picture.

Keep doing this until the pictures are the way you want them.

This is a decent lens for the price and worth the little money they cost if you can't afford $10,000 plus for a high quality telephoto lens of this size. I would forget about the 2X doubler because as others have said, it further reduces the speed of an already very slow lens with such a high rate of magnification that a knat landing on the lens could cause the picture to blur from movement.

Jun 26, 2011 | Opteka 650-2600mm High Definition...

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What are the best settings to use the Opteka 500MM Mirror Lens with a Pentax K-7. Also when you you add the 2.0X teleconverter with this lens?

These big lenses are very slow and cannot deliver much light to your camera. Obviously, you can't open the aperture any wider than f8 as specified by the lens itself. In the old days, most inexpensive cameras were fixed focus at f8 with a shutter speed of 1/100 sec. That's a good place to start with this lens without the doubler.

If the pictures are too dark, you can't open the lens any wider so your only option is to reduce the shutter speed.

That means that motion of the shooter or the subject will be more inclined to cause blurring so you need to be shooting from a tripod with a remote shutter release and/or a delayed shutter release setting.

If the test picture is too light, I would first reduce the lens opening to the next stop, f9 or f11, then shoot another test shot. You could also increase shutter speed, or both o reduce the light reaching the camera sensor. Keep shooting test shots until you get the exposure you want.

Once you add the doubler, you compound this situation because it will further reduce the lens speed by about 2 f-stops, meaning that you have to start your tests at f-11 at 1/100 sec. or f-11 at 1/50 sec. This gives you far less flexibility to properly adjust exposure.

Further, you will have increased the magnification so much that a slight breeze or a fly landing on the lens can cause vibration and blur the picture.

Before you shoot any serious pictures, you need to experiment with this lens so that you know exactly what its capability is.

Jun 23, 2011 | Opteka 500mm f8 for Pentax K

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I have a weird problem. When i put the 50mm 1.8 on my D90 it continues to autofocus even when I switch the camera body to M mode instead of AF with the switch. I would like to be able to manually focus...

You probably have a problem with the A/M switch on the body-- flipping that switch should extend or contract the autofocus pin that drives the lens. This particular lens doesn't have its own focus motor, so there's no way that it could be focusing on its own without the pin from the body driving it.

Try taking the lens off of the camera and looking at the autofocus pin as you flip the switch from auto to manual focus.

Mar 10, 2011 | Nikon Normal AF Nikkor 50mm f/1.8D...

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How do I adjust my Canon EF 100-400mm infinity setting on the lent. 300 to 400mm is out of focus.

I don't know your photography background and skill, so these tips may seem overly basic.

Have you tested this on a tripod? Not using a tripod can add a lot of blur, even while using the IS.
I would also try the lens at f/8 and see if you have the same focus issues. If not, it may just be related to shooting the lens wide open, where it's not the sharpest.
I hope this helps. It's just a few things to try.
Send a comment if you'd like some other possibilities.
Happy shooting with a great lens!

Mar 06, 2011 | Canon EF 100-400mm f/4.5-5.6 IS USM Lens

1 Answer

My Nikon 55-200mm will not function in autofocus mode. works just fine in manual. Switch is on autofocus on the lens. I hear a small click from the body when i try to AF, but get nothing from the lens.

hi there,

i`ve once experienced the same problem as your,
the reason was the motor in the lens. it couldn`t work normally
to trouble shoot this, you should contact a professional service technician,
and i hope the lens is still in warranty condition


Jan 16, 2011 | Nikon Nikkor 55-200mm f/4.5-5.6 G AF-S...

1 Answer

When I attach my Lensbaby, I get a message saying "No lens". I know I'm attaching it correctly.

The Lensbaby does not incorporate any electronic circuitry. Without any, the lens cannot communicate with the camera. That is what the F-- message indicates. Without the communications, the camera cannot meter the exposure since it doesn't know what aperture the lens is set to.

Your lens is on properly. You just can't meter through it. You can use a separate light meter, meter through a different lens, or simply shoot and adjust the exposure by looking at the result and the histogram.

Sep 08, 2010 | Lensbabies Composer LB3N f?r Nikon Lens

1 Answer

What is the purpose of the limit/full switch

It limits the focus range. In full, the camera will hunt from one end of the focus range to the other as it seeks to autofocus. You can limit the hunting to one end or the other if you know what you're shooting. This saves time (and battery power) by not hunting focus all over the place.

Jun 10, 2010 | Canon Sigma 105MMF2.8 EX Macro AF Lens for...

3 Answers

Nikon d200

I would recommend the 17-35mm f2.8D ED-IF rather than the G series

Feb 23, 2008 | Nikon 18-70mm f/3.5-4.5G ED-IF AF-S DX...

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