new camera from beach; need help with add'l lens purchase

[southgal]

Just received pentax dl with kit lens from Beach Camera and am trying to decide which of the following options would be best. Experience with Beach was great - fast shipping, no high-pressure phone calls, and great price.

Option 1: buy pentax 50-200 zoom with tamron 1.4x converter
Option 2: buy tamron/sigma 28-300 zoom
Option 3: sell kit lens and buy sigma 18-125 and sigma/tamron 70-300
Option 4: sell kit lens and buy sigma/tamron 18-200 with tamron 1.4x converter

Regardless of which option is chosen, I will be buying a fast prime and a macro lens in the future. I'm betting most of y'all will go for option 3 based upon my lurking on this forum for the past 6 months, but I'd still appreciate a specific recommendation. I am a dslr-newbie and am upgrading from a canon s1is. I will use this for disney once a year, beach/mountains once a year, but want to use more for photography rather than snapshots. Thanks for your previous help while lurking, and thanks in advance for specific help now.

Robert (southgal's dh)

 

[Kelly Grannell]

never buy a converter if your lens is worse than f/4. You don't only magnify, but you only reduce the aperture by the same factor. The 18-200, for example, is f/6.3. With the TC, it'll be about f/8 which means the sweet-spot of the lens have turned into around f/11, completely useless for indoor shooting.

The best if option 3 although I don't know who's going to buy a kit lens (not because it's bad, but because there are so many out there.)

 

[southgal]

never buy a converter if your lens is worse than f/4. You don't only magnify, but you only reduce the aperture by the same factor. The 18-200, for example, is f/6.3. With the TC, it'll be about f/8 which means the sweet-spot of the lens have turned into around f/11, completely useless for indoor shooting.

The best if option 3 although I don't know who's going to buy a kit lens (not because it's bad, but because there are so many out there.)

Thanks for the quick response! Thankfully, option 3 is not contingent upon the kit lens selling -- if it does, great; if not, that's ok, too. Kelly, you are a wonderful resource for this forum and I enjoyed your blog. Thanks again.

Robert

 

[0bli0]

if you do buy a teleconverter, i highly recommend the Tamron SP version (the white one). it is much sharper than the standard Tamron (black one) and you ill have less AF problems. it ill also report the correct aperture and record the correct focal length (where supported by the lens). note the Kenko Pro is the same as the Tamron SP. i'd avoid any of the 2x teleconverters.

-teleconverters tend to reduce lens drive speed considerably to aid in AF. use single AF spot for focus.

-Canon teleconverters will only work with a select few Canon lenses.
-teleconverter springs are often not as strong as the normal body mount springs. be careful with heavier lenses. also be careful with tripod/monopod mounted lenses due to the leverage applied to the body by your hand.