0.7x Super Reducer – 3

This shows a new reducer’s performance for birding application. As described below, this configuration includes 1.7x Pentax AF adapter. Generally this AF adapter is not effective in image quality. But see this resolving power with 71FL and a new reducer.

71FL+M75 Iris+0.7x reducer+1.7x Pentax AF adapter+Pentax K5

BTW, I found out 7923(adapter which allows DSLR adapter to connect M57 directly) has M52 filter thread. It is also possible for M48 filter with a stepping ring. If someone are looking for the solution to set 2″ filter in front of camera, this might be good idea. Especially 1.08x field flattener – 7108 doesn’t have filter thread. So you may set LPS filter here.



~ by tedishikawa on August 30, 2011.

5 Responses to “0.7x Super Reducer – 3”

  1. Hey Ted,

    That’s some setup, especially to be hanging from what appears to be a gate.

    I’m confused, again!

    You mention a 7923 adapter, but the picture shows a 5005.

    Is the 7923 hidden between the 5005 and the filter, or what?



  2. Why use a reducer AND an extender in the same setup? Is this just to get to a desired focal length?

  3. Perry,

    You can see the theaded section between 5005 and a filter.
    That’s 7923. If you have 5005 in your hand, you will see. 5005 has
    M49.8 female. Not male thread.


  4. Josh,

    Do you ask about Pentax 1.7x AF adapter? If so, this is auto-focus adapter, which lets BORG scopes have AF capability. Pentax has only one teleconverter. As long as I know, this is only one AF adapter commercially available in the market. So no other choice. Why reducer is used? The scope needs to be fast speed for AF function.


  5. Ted,

    Two things.

    OK, the 7923 is “hidden” between the 5005 and the filter. I thought that must be the case. There are 3 separate pieces there, not 2.

    Regarding the Pentax 1.7x AF adapter – I’m really unsure how this works in autofocusing (AF) BORG scopes. I can see how it might function on manual focus with a “beep” like the Canons can do with an appropriately “chipped” adapter.

    But to truly autofocus a Borg scope using a DSLR in autofocus mode Is a development I have not seen from any other scope manufacturer.

    I don’t see how I could do that with my Borg 100ED or my 125ED. I don’t see any means for them to “talk back” to a camera, of any sort, via a “chipped” adapter so as to do AF.

    As mentioned, I can do manual focus (MF) of third party lens and scopes using a “chipped” adapter on my Canon 60D, which “beeps” when that optic is in focus.

    Am I missing something here?? Again!!!

    And thanks!


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: