Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
05-11-2010, 05:39 AM   #16
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
warning, Math Involved

QuoteOriginally posted by dadipentak Quote
I have a 1000mm lens and 1.4x, 1.7x & 2x TCs and there are still things that are out of reach! Save your money & get close.
even when you stack them all together, the moon is still 250,000 miles away

But you do raise a point

Image size = subject size x focal length / distance

getting closer is the best approach and also the cheapest,

When you consider some of the shots I posted/linked earlier, all but the whooping crane (big white bird) are full frame shots, where I was close enough to fill the entire sensor, or almost do so, with the subject (in each case the whole bird). The whooping crane is an exception, it is 10% of the area cropped out of my K10D somewhat proving your point that things can be out of reach regardless of focal length attached.

05-11-2010, 07:24 AM   #17
Loyal Site Supporter
dadipentak's Avatar

Join Date: Jul 2008
Location: Baltimore, Maryland
Photos: Gallery
Posts: 10,404
QuoteOriginally posted by Lowell Goudge Quote
getting closer is the best approach and also the cheapest,
To some extent it's a "Do as I say not as I do" sort of thing, I'm afraid but all of my good shots have been those where cropping was minimal. If I've learned one thing it's that filling the frame is essential to getting all the resolution your gear can deliver.
05-11-2010, 08:14 AM   #18
Loyal Site Supporter
imtheguy's Avatar

Join Date: Mar 2009
Location: Virginia Beach
Photos: Gallery | Albums
Posts: 2,950
QuoteOriginally posted by Skog Quote
Thank you for all your answers

The DA * 300 + 1,7 TC seems the best choise so far. That would give me a 510mm f7,1 right? Good for some really good light situations I guess. But I can just use the 300mm alone in those days, and just accept that some will be out of reach
Close, the camera actually reads f/6.7 when the TC is mounted.

And I certainly agree with Lowell that this does not make it a bright light only combo. Heck the Bigma at 500mm wide open is f/6.3 and requires a little stopping down for best IQ.

  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
da, fa, k-mount, pentax lens, sharpness, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Pentax SMC 500mm/f4.5 Telephoto Lens, Pentax Rear Converter A 2X-L. David I. Sold Items 11 09-16-2009 07:11 AM
Telephoto willessean Pentax SLR Lens Discussion 1 09-11-2009 04:50 AM
need telephoto help button Pentax SLR Lens Discussion 21 04-23-2007 02:34 AM
Which Telephoto to Buy? kpfeifle Pentax SLR Lens Discussion 5 03-11-2007 12:46 PM

All times are GMT -7. The time now is 12:53 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]