Lens?

dream rider

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Hello,

I have a Pentax K1000 with a K-mount lens mount, and i was wondering if anyone could recomend a lens that i can get close to the subject with, and also have lots of DOF, please help me, im very new to the photography world, thanks!


Jeff
 
Sounds like you want a fast macro lens. Macro lenses allow your to get high reproduction ratios. All you'll need to do to get a high DOF is stop it down and light your subject well. I'm sure if you do a ebay search or check out bhaudiovideo or adorama you could find a grip of lenses that fit the bill for a variety of price ranges.
 
With an older style mount like the K1000, you'll prolly have better luck finding some exstension tubes to use with your existing lenses. Macros will be harder (and way more exspensive) to find. That's the route I'd go anyway.........

edit: and with any type of macro, lots of DOF is hard to come by
 
For the K-mount, there are two very popular macro lenses available. I have the 100mm pentax-M macro f/4. It was purchased at a local camera swap for $100. I've only shot a couple pictures but so far I am satisfied. Pictures could be better if I had a ring light. Lighting always seems so difficult with macro shots. The other macro lens is a 50mm macro. This lens was just slightly more expensive ( 10bucks or so ) then the 100mm macro. sorry no experience with it.

With the 100mm and 50mm macro lenses, your going to have a pretty shallow DOF. Depending on how close ( or the magnification ) of the subject, you might get away with a wide angle lens that has a very short minimum focal distance ( some post production cropping might be necessary ). This should give you more DOF than either 100mm or 50mm macros even at very small aperatures.

Another option that was already brought up was the use of extension tubes with some fast primary lens. Many don't really like using extension tubes but its a lot of bang for buck. I personally had a great time experimenting with a bellows unit acquired for my m42 screwmount system paired with the takumar 50mm f1.4. Allows for infinite adjustment and was purchased for under 30 bucks... Very flexible setup although can be a pain to get just right.

Either way, you should not spend a lot of money. There are numerous K-mount lenses available out there... if you are willing to use an Kmount to m42 screwmount adapter the choices are even more mind boggling...
 
do wider angled lenses allow you to get closer? if i had a 50mm would a 28mm allow me to get even closer than the 50? im not looking to get to amazingly closer, also would a 28mm have more DOP than a 50? Im really new so im not looking to go to high tech or anything. thanks!

P.S. im on a budget, i know of Henrys.com, so ill probably be buying used from there.


Jeff
 
Jeff:

There's a very, very nice Pentax 100mm F/4.0 Macro lens on sale at Ebay. Do a search on item number and you'll set it. As is, this lens will get you down to a reproduction range of 1:2 - see below for an explanation. The price is about right, but may not be "right" for your budget. So save your money or borrow it from someone - not me - ;>) - and pay them back.7538692566
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FYI - all lens will exhibit the same depth of field IF (1) they are used at the same aperature and (2) at the same ratio of reproduction - area covered by the film to the area covered. Therefore, a ratio of reproduction of 1:3 would indicate that the are covered by the lens is three times the area of the film.

For confirmation, check the tables in the back of some of the older, and still excellent books, such as The Pentax Way by Keppler. Used books in various conditions and prices can be found at either alibris.com or at abe.com

I wouldn't waste my time or money on extension tubes or close up lenses - for one the image quality will not be as good and you won't have continous focusing from infinity down to a ration of reproduction of 1:2. The appropriate extension tube - used in conjunction with the lens referred to above will get you down to 1:1.

Hope this information is useful.

Bill
 
yup.. the macro on ebay is the same lens I have; Pentax 100mm f4 macro. There's an online calculator that you can play around with; http://www.dofmaster.com/dofjs.html
Play around with the input variables and see how it affects the DOF etc... Compare the total depth of field's between wide, normal and telephoto lenses at varying distances but at a constant aperature.
 

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