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mxfun
04-08-2007, 16:58
hi ,just wondered if anyone could point me in the right direction ,not long bought a Pentax K100D with the standard kit lens..ie 18-55 mm ,i'm really keen to get into macro photography ,so,i bought an extension tube to fit on the kit lens to experiment the damn thing don't work...help!!! anyone:shrug:

namllihs
04-08-2007, 17:04
not working how?

RobertP
04-08-2007, 21:48
The difference in how close you get to the subject can be quite dramatic. You might find things are in focus an inch from the front of the lens with the spacer!

They do work better with longer focal lengths. i used to use them with a 70-200. If you only have the one lens try at the 55mm end. Forget about autofocus even if it works. Focus by moving towards or away from your subject.

I don't know the pentax kit at all but we might be able to guess our way round your problems if you still have them. Let us know how you get on.

mxfun
05-08-2007, 10:49
not working how?

when it's fitted the view is very dark and hazy even when i'm close up to whatever i'm trying to take a shot of ,prob a simple solution to solve it and i haven't spotted the obvious :help:

RobertP
05-08-2007, 13:54
Are these simple spacer tubes or 'auto' ones with connections that allow the AF to work?

mxfun
05-08-2007, 15:11
Are these simple spacer tubes or 'auto' ones with connections that allow the AF to work?

eh... nope...:bonk:

mxfun
05-08-2007, 15:15
Are these simple spacer tubes or 'auto' ones with connections that allow the AF to work?

sorry bit quick with my reply ,yes they're the plain tubes.I'm sure i read somewhere that they would work on ma K100D:shrug:

namllihs
05-08-2007, 15:17
As Robert says, you will need to be almost on top of the subject to focus and DOF will be very narrow.

RobertP
05-08-2007, 16:15
Next step then... is the iris (aperture) open wide on the lens or shut right down? With the lens off the camera can you see through it or is there just a dot of light in the middle?

If it is closed right down that will be why it is so dark and might be an insurmountable problem. You need an aperture in the f8 to f13 sort of range for macro. Answer then would be a cheap manual lens from ebay and use that for macro as you can set the aperture on the lens itself.