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02-22-2009, 09:37 AM   #1
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need help with new lens :(

Hi all,
It was my birthday yesterday and my gf bought me a new lens
As thrilled as I were, I seemed to have trouble trying to get one of the functions to work.

This is the lens she got me:
Sigma - Lenses
70-300mm F4-5.6 APO DG MACRO


I tried to use the macro function but couldn't get it to work. I kept on getting blurry views that can't be focused properly when I push up the macro button.
I couldn't make much out of the tiny supplied manual so I decided to look it up on the net. But unfortunately I couldn't find any how-to's on this, or similar lens.

I'm trying to use it with a pentax k100D super btw.

I'm really a noob on these things so any help much appreciated!

Thanks and regards.

02-22-2009, 10:08 AM   #2
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Perhaps a silly question, but did you try backing up? The min focus distance is 95cm (about 3ft).
02-22-2009, 10:19 AM   #3
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^
Yep, tried that already.
Same thing unfortunately.
02-22-2009, 11:39 AM   #4
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I don't have this lens so I'm going to make general suggestions which may be more stuff you've tried. For this type of photo, you'll need a lot of light. Noon at the height of summer in a tropical location is a good start. The light is needed so you can have a good shutter speed, like 1/125s or 1/250, and a small aperture like f11 or f16. You'll probably also need to go to ISO 400 or more. Those settings sound extreme for regular photography, but for macro photography you need them for decent depth of field and to reduce the possibility of camera shake or subject movement. With high magnification at close distances, your depth of field at f5.6 or f8 will be way too small.

If you don't have that much light, a tripod can help. Sometimes it is tricky getting a tripod to hold the camera in the right place for your subject, but the extra stability is very useful. Remember to turn SR off on a tripod. It can be much easier to move the camera than refocus. Autofocus might not be able to get the exact point of focus you want, so you might try manual focus. Wind can easily ruin a macro shot by moving the subject, causing both motion blur and changing where your point of focus is. So make sure it's a calm day at noon in the summer in the tropics.

It will probably take some experimental pictures to figure out your problem. Check your settings first, and try my settings above to see if they work better. Then if you can post a photo with your settings and details, we can help more.

02-22-2009, 12:06 PM   #5
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Do you understand that the Macro function only works at 200mm or more?
02-22-2009, 12:13 PM   #6
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QuoteOriginally posted by wildman Quote
Do you understand that the Macro function only works at 200mm or more?
Text from Sigma website description

"Macro shooting with maximum magnification 1:2


High optical performance is demonstrated throughout the entire zoom range. It also has a switch that converts the lens to macro photography at focal lengths between 200mm and 300mm with a minimum focusing distance of 95cm (37.4 inches). In normal mode the minimum focusing distance is 150cm (59.1 inches) at all zoom settings. Maximum magnification between 200mm and 300mm is 1:2.9 to 1:2."
02-22-2009, 12:18 PM   #7
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QuoteOriginally posted by wildman Quote
Do you understand that the Macro function only works at 200mm or more?
Yes I do actually. But that's the thing. When it's set to 200-300mm it gets REALLY blurry and manual or automatic focusing does just about nothing.

02-22-2009, 12:33 PM   #8
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QuoteOriginally posted by wingk1314 Quote
This is the lens she got me:
Sigma - Lenses
70-300mm F4-5.6 APO DG MACRO

......

I'm trying to use it with a pentax k100D super btw.
As I had the older quantaray branded version of this lens my first question is to ask if you are trying to do Macro while handholding the camera? You may have made a slight movement forward or backward to cause the image to go out of focus. Second question would be what are you taking pictures of? If your subject moves away or towards the camera in the slightest while taking the picture the captured image my be out of focus. Shake reduction cannot work miracles for you. Post a picture and we might be able to get a better indication of what is actually happening.
02-22-2009, 01:17 PM   #9
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Do you get any decent pics at any setting?

Just went out to where the cats are sleeping and took a few quick and dirty shots with your lens just to show what it should be able to do. Hand held full frame.
first normal and the second macro

Last edited by wildman; 02-23-2009 at 05:02 AM.
02-22-2009, 11:22 PM   #10
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QuoteOriginally posted by wingk1314 Quote
I tried to use the macro function but couldn't get it to work. I kept on getting blurry views
Well, what shutter speed were you using? What aperture? Are you aware the DOF can be *extremely* shallow when doing macro photography? There might only be one millimeter in focus. The way to get greater DOF is to stop down the aperture, but that means slower shutter speeds, which means camera shake, which means blur.

Could you post some pictures you weren't happy with and say what aperture and shutter speed they were at?
02-22-2009, 11:55 PM   #11
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Happy Birthday!

I just glanced through the replies here so if I'm being repetitive I apologize.

How far away are you from the subject you are trying to take a macro shot of?

Because, just as there is a minimum focusing distance, meaning how close you can get to the subject and be able to focus...

...There is probably also a maximum focusing distance in the macro mode. In other words, you may not be able to focus on something say 20ft away in macro mode. You may only be able to be able to focus between 3 and 7ft.

It would be the same as using extension rings, where you gain the ability to focus closer but lose the ability to focus on distant objects.

Hopefully that makes sense.

Regards,
Mike
QuoteOriginally posted by wingk1314 Quote

I tried to use the macro function but couldn't get it to work. I kept on getting blurry views that can't be focused properly when I push up the macro button.
02-23-2009, 01:45 AM   #12
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As said above, your distance from the subject should not be too close. Try it outdoors in daylight. I've got the same lens and the macro works fine but too close will be mush. Good natural light should get you shutter speeds that won't blur on you. It's also not truly macro but close up anyway. An example of a macro picture with the lens
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