Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
06-01-2015, 07:52 AM   #1
New Member
premy2u's Avatar

Join Date: Jul 2014
Posts: 4
Pentax 645 iso 400 vs Spotmatic iso 25

Can I say "I don't need to get a Pentax 645 to get nice 11x14 enlargements. I can use very fine grain film like Rollei-25 with a 35mm Spotmatic and get about the same results as a Pentax 645 with iso 400 film." ?
Am I missing something?

06-01-2015, 08:13 AM   #2
Dark Underlord
Loyal Site Supporter
AquaDome's Avatar

Join Date: Jan 2014
Location: New Carlisle, IN
Photos: Gallery | Albums
Posts: 1,475
Enlarging to 11x14 inches from a 24x36mm negative is stretching less image data over a large area than it would be with a 56x41mm negative. No matter what you do in 135 format, if you do the same in 645, you get more. But, if enlarging to 11x14 inches from your high-quality 24x36 negative produces the results you are seeking, you probably don't need the "more".
06-01-2015, 09:36 AM   #3

Join Date: Feb 2009
Location: Arizona
Posts: 1,007
You could rationalize not getting a 645 for that reason but you can get fine grain film for the 645 like Ektar 100 or Velvia 50. In those cases, there is going to be a noticeable difference in favor of the 645.
06-01-2015, 12:41 PM - 1 Like   #4
Senior Member

Join Date: Mar 2015
Posts: 160
Keep the spotmatic and stop trolling.

06-01-2015, 01:13 PM   #5

Join Date: Jul 2010
Location: Oregon
Photos: Albums
Posts: 1,419
Digital systems caught up to the Pentax 6X7 many years ago. Since then, the gap has widened a lot. I can do bigger prints with my k-5 than I did with my 6X7. Also, I have several stops more dynamic range available with digital. There is some tonal advantage still with B&W film, but otherwise, digital wins.
06-01-2015, 04:00 PM   #6

Join Date: Feb 2009
Location: Arizona
Posts: 1,007
Civiletti- The question had nothing to do with digital.
06-01-2015, 11:52 PM   #7

Join Date: Jul 2010
Location: Oregon
Photos: Albums
Posts: 1,419
Oops. As Emily Litella would say, "Nevermind".

  • 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!
645d, 645z, camera, iso, iso 400 vs, medium format, pentax, pentax 645 iso, pentax-645, spotmatic, vs spotmatic iso
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
GR auto ISO @ 400 MBike74 Ricoh GR 5 01-26-2015 07:38 AM
Kr lowest ISO is 400 Tim A Pentax K-30 & K-50 3 01-17-2014 05:31 PM
ISO 80 vs ISO 100 shaolen Pentax K-5 30 12-05-2013 11:05 AM
Kentmere 400 ISO, Pentax Spotmatic 500, Takumur 55 f2.0 jeztastic Film Processing, Scanning, and Darkroom 9 09-30-2013 05:07 AM
Default ISO 200 vs ISO 100 joodiespost Troubleshooting and Beginner Help 6 01-09-2010 05:50 PM

All times are GMT -7. The time now is 04:56 AM. | 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]