Extension tubes question

creampuff · 05-08-2009, 06:16 PM

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Aside from extension tubes, you can also:
- use a bellows
- reverse a lens (using a wider focal length lens will give higher magnification)
- stack another lens (requires DIY modifications)
- use a supplementary lens in front of the lens (poor edge sharpness, limited magnification)
- buy a Canon camera and the Canon's MP-E 65mm Macro lens (gives 1x to 5x magnification)

jem · 05-08-2009, 06:31 PM

Peter Zack has written a very nice set of articles on Macro Photograpy that he published on his blog starting here: Shooting Macros.
There are 3 parts in total. They might help answer some of your questions about equipment and technique.

yeatzee · 05-08-2009, 06:36 PM

believe me, I've been envying that MP-E65 in canon's camp....and their MT-24EX! Wish pentax would make something similar because I like them much more than canon.

yeatzee · 05-08-2009, 06:46 PM

I still need to know, will the bellows on ebay which say K-PK mount work with my sigma lens?

Edit: Lens Macro Fold Bellows for Pentax K-PK (D)SLR Camera - eBay (item 160332903646 end time May-11-09 03:09:18 PDT)

does it mean K mount through PK mount? Im confused

jem · 05-08-2009, 07:08 PM

Originally posted by yeatzee

I still need to know, will the bellows on ebay which say K-PK mount work with my sigma lens?

Edit: Lens Macro Fold Bellows for Pentax K-PK (D)SLR Camera - eBay (item 160332903646 end time May-11-09 03:09:18 PDT)

does it mean K mount through PK mount? Im confused

Yes that bellows should work with your Sigma. You will probably have to treat it as a manual lens, use your aperture ring and use the green button to set exposure though.

I believe K & PK mean the same thing in this instance.

yeatzee · 05-08-2009, 07:57 PM

Thanks, according to my calculations a decent 28mm lens + the bellows will give me a wopping 5:1! Now off to bid on a M 28mm F2.8

SOldBear · 05-08-2009, 09:01 PM

Originally posted by yeatzee

Thanks, according to my calculations a decent 28mm lens + the bellows will give me a wopping 5:1! Now off to bid on a M 28mm F2.8

Have you calculated as how far (or rather, how close) the subject has to be to get to 5:1?

I don't have the number in my head, but I'm not surprised if the subject has to be inside the bellow, between the body and the lens.

newarts · 05-09-2009, 07:41 AM

Originally posted by yeatzee

Thanks, according to my calculations a decent 28mm lens + the bellows will give me a wopping 5:1! Now off to bid on a M 28mm F2.8

I recommend starting with your sigma 105: with a typical bellows you might get as much as 2.5:1.

You will discover that that 2.5:1 is a LOT of magnification and you will have difficulty in making things stable enough, lighting properly, focusing, etc.

With a shorter lens, the magnification will be higher but you'll have less distance in front of the lens to work with (working distance.)

For magnifications of 5:1 or more you might be better off adapting your camera to a microscope.

Iowa Dave

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05-08-2009, 06:16 PM	#16
creampuff Veteran Member Join Date: May 2007 Location: Singapore Photos: Gallery Posts: 3,953	Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here. Aside from extension tubes, you can also: - use a bellows - reverse a lens (using a wider focal length lens will give higher magnification) - stack another lens (requires DIY modifications) - use a supplementary lens in front of the lens (poor edge sharpness, limited magnification) - buy a Canon camera and the Canon's MP-E 65mm Macro lens (gives 1x to 5x magnification)

05-08-2009, 06:31 PM	#17
jem Senior Member Join Date: Feb 2009 Posts: 217	Peter Zack has written a very nice set of articles on Macro Photograpy that he published on his blog starting here: Shooting Macros. There are 3 parts in total. They might help answer some of your questions about equipment and technique.

05-08-2009, 06:36 PM	#18
yeatzee Veteran Member Join Date: Feb 2009 Location: Temecula Photos: Gallery \| Albums Posts: 3,675 Original Poster	believe me, I've been envying that MP-E65 in canon's camp....and their MT-24EX! Wish pentax would make something similar because I like them much more than canon.

05-08-2009, 06:46 PM	#19
yeatzee Veteran Member Join Date: Feb 2009 Location: Temecula Photos: Gallery \| Albums Posts: 3,675 Original Poster	I still need to know, will the bellows on ebay which say K-PK mount work with my sigma lens? Edit: Lens Macro Fold Bellows for Pentax K-PK (D)SLR Camera - eBay (item 160332903646 end time May-11-09 03:09:18 PDT) does it mean K mount through PK mount? Im confused

05-08-2009, 07:08 PM	#20
jem Senior Member Join Date: Feb 2009 Posts: 217	Originally posted by yeatzee I still need to know, will the bellows on ebay which say K-PK mount work with my sigma lens? Edit: Lens Macro Fold Bellows for Pentax K-PK (D)SLR Camera - eBay (item 160332903646 end time May-11-09 03:09:18 PDT) does it mean K mount through PK mount? Im confused Yes that bellows should work with your Sigma. You will probably have to treat it as a manual lens, use your aperture ring and use the green button to set exposure though. I believe K & PK mean the same thing in this instance.

05-08-2009, 07:57 PM	#21
yeatzee Veteran Member Join Date: Feb 2009 Location: Temecula Photos: Gallery \| Albums Posts: 3,675 Original Poster	Thanks, according to my calculations a decent 28mm lens + the bellows will give me a wopping 5:1! Now off to bid on a M 28mm F2.8

05-08-2009, 09:01 PM	#22
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by yeatzee Thanks, according to my calculations a decent 28mm lens + the bellows will give me a wopping 5:1! Now off to bid on a M 28mm F2.8 Have you calculated as how far (or rather, how close) the subject has to be to get to 5:1? I don't have the number in my head, but I'm not surprised if the subject has to be inside the bellow, between the body and the lens.

05-09-2009, 07:41 AM	#23
newarts Inactive Account Join Date: Dec 2008 Location: Ames, Iowa, USA Photos: Albums Posts: 2,965	Originally posted by yeatzee Thanks, according to my calculations a decent 28mm lens + the bellows will give me a wopping 5:1! Now off to bid on a M 28mm F2.8 I recommend starting with your sigma 105: with a typical bellows you might get as much as 2.5:1. You will discover that that 2.5:1 is a LOT of magnification and you will have difficulty in making things stable enough, lighting properly, focusing, etc. With a shorter lens, the magnification will be higher but you'll have less distance in front of the lens to work with (working distance.) For magnifications of 5:1 or more you might be better off adapting your camera to a microscope. Iowa Dave