Go Back   IceInSpace > Equipment > Astrophotography and Imaging Equipment and Discussions

Reply
 
Thread Tools Rate Thread
  #1  
Old 16-08-2019, 10:44 AM
OICURMT's Avatar
OICURMT
Oh, I See You Are Empty!

OICURMT is offline
 
Join Date: Apr 2010
Location: Laramie, WY - United States of America
Posts: 1,438
Question My wife's new toy... I'd like to use it as well :)

My missus has wanted to get "closer" to wildlife and has been a little frustrated with her camera setup. So, I purchased her a Minolta High Speed AF Apo Tele 600mm f/4 G telephoto for her to be able to get much closer than the 200mm she has.

She shoots with a Sony camera (an old a350, a-mount). The len I bought was basically in mint condition (photos attached). Only a scratch on the case itself, lens was in perfect condition, including exterior paint. the 1.4x teleconverter (giving her 800mm f/5.6) and all filters were even included. I got it for a great price... and the missus is happy, so you know... "happy wife, happy life".


I'd like to be able to get my QHY and/or ZWO onto it, but as Steve Mogg is out of business, I was wondering if anyone knew of a source on where to get an A-mount lens to T2 (T-thread). I'd prefer not to go to Precise Parts because let's face it, that's an expensive route for me just wanting to test the telephoto on the night sky.


Advice sought...
OIC!
P.S. For those who are interested, I bought it on eBay from Japan. Arrived in five days.
Attached Thumbnails
Click for full-size image (1.jpg)
115.7 KB43 views
Click for full-size image (2.jpg)
146.1 KB40 views
Click for full-size image (3.jpg)
146.8 KB33 views
Click for full-size image (4.jpg)
105.3 KB39 views
Click for full-size image (5.jpg)
117.4 KB34 views
Click for full-size image (6.jpg)
87.5 KB43 views
Click for full-size image (7.jpg)
67.1 KB40 views
Click for full-size image (8.jpg)
65.2 KB32 views
Reply With Quote
  #2  
Old 16-08-2019, 10:53 AM
bojan's Avatar
bojan
amateur

bojan is offline
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,885
I think she will make a big mistake if she let you try it....
Reply With Quote
  #3  
Old 16-08-2019, 11:02 AM
strongmanmike's Avatar
strongmanmike (Michael)
Woohoo it's clear

strongmanmike is offline
 
Join Date: May 2006
Location: Canberra
Posts: 14,657
Wow! a 6" F4 APO...nice

Good luck with getting the adapter.

Mike
Reply With Quote
  #4  
Old 16-08-2019, 12:21 PM
JA
.....

JA is offline
 
Join Date: Oct 2016
Location: Melbourne, Australia
Posts: 1,436
Nice pickup OIC.

As for the adapter, you've probably already searched and gathered that they're the wrong way around for your use. You need
Female Minolta A Bayonet to an M42x0.75 MALE thread to screw in to the QHY10's M42x0.75 FEMALE thread.

The flange focal distance for a Minolta A mount/ Sony A is supposed to be 44.5mm and the QHY10's sensor is set back 20mm from the front (although from exactly where isn't clear in any diagrams I could find). Take it as the front surface where the M42x0.75 FEMALE thread starts.

Using those "FACTS" (???) you could use an M42 focusing helicoid of appropriate length and some how attach a Minolta female bayonet to its front surface. You probably could use an M42 to M52 focusing helicoid to reduce chances of vignetting and providing space for the female bayonet mount, which you could obtain from a Minolta A mount photographic extension tube. A bit of skill and join the two and hey presto done for probably $80 or less, with the added advantage that since you've used a focusing helicoid instead of fixed extensions, then you can fine tune the distance.

It certainly would be an easy-ish way to get a look at your camera on the new lens, which brings me to the easiest way, but you need a machinist friend or skill: A cylindrical collar that neatly, snuggly and with minimal play slips over the outer body of the camera on one end and the circa 70mm cylindrical lens body at the other end. Boring/machining it on a lathe will provide enough concentricity for the purposes of a lens test.

I will post an couple of images to clarify later.

For the helicoid focuser shown in the first image below the link is: https://www.ebay.com.au/itm/Brass-M5...wAAOSw1QpaBZGl
This is probably the correct adjustment range (25 to 55mm in length) to use (although longer is available) and it uses a brass helicoid rather than aluminium which has a tendency to sometimes stick.

SO it connects directly to your camera at one end (VERIFY: helicoid is actually M42 x 0.75PITCH) and at the larger (M52) end screw or somehow attach a Minolta Female A mount bayonet from a photographic extension tube of the type shown in the 2nd attached image. You could remove the bayonet flange and screw it to the face of the large (M52) end of the focusing helicoid or "jimmy" something up.

I hope it works out one way or another. Of course if you had a CaNikon then QHY already make said adapters.

Best
JA
Attached Thumbnails
Click for full-size image (M42 to M52 Helicoid Focuser.jpg)
126.8 KB7 views
Click for full-size image (Minolta-Sony A Mount Extension Tube.jpg)
56.9 KB7 views

Last edited by JA; 16-08-2019 at 12:56 PM.
Reply With Quote
  #5  
Old 16-08-2019, 02:10 PM
leon's Avatar
leon
Registered User

leon is offline
 
Join Date: Apr 2006
Location: ballarat
Posts: 10,804
Wow she is a lucky lady indeed, yea as said you keep you hands off it.

Leon
Reply With Quote
  #6  
Old 16-08-2019, 03:30 PM
FlashDrive's Avatar
FlashDrive (Col)
Senior Citizen

FlashDrive is offline
 
Join Date: Apr 2008
Location: Brisbane North
Posts: 4,122
Gee ....that's a NICE Lens
Reply With Quote
  #7  
Old 16-08-2019, 05:08 PM
gbeal
Registered User

gbeal is offline
 
Join Date: Oct 2004
Location: New Zealand
Posts: 4,299
OIC,

Fortuitously (or not) I "might" have what you seek.

Sent you a PM.

Gary
Reply With Quote
  #8  
Old 16-08-2019, 11:27 PM
OICURMT's Avatar
OICURMT
Oh, I See You Are Empty!

OICURMT is offline
 
Join Date: Apr 2010
Location: Laramie, WY - United States of America
Posts: 1,438
Quote:
Originally Posted by JA View Post
Nice pickup OIC.

As for the adapter, you've probably already searched and gathered that they're the wrong way around for your use. You need
Female Minolta A Bayonet to an M42x0.75 MALE thread to screw in to the QHY10's M42x0.75 FEMALE thread.

Best
JA
Quote:
Originally Posted by gbeal View Post
OIC,

Fortuitously (or not) I "might" have what you seek.

Sent you a PM.

Gary
Best part about IIS... everything (ok, maybe not the poli-discussions )... Great advice, knowledgable and helpful people.

Sent Gary a PM.


JA, thanks, I'm on it... I found an A-mount macro extension tube on eBay, messaged the vendor to get a thread size and pitch... maybe I'll get lucky. https://www.ebay.com/itm/123856710771
You are correct regarding the 20mm. I remember having a discussion with Mogg when I purchased an adapter for my Canon FD lenses.

Thanks again everyone and to be clear, the missus is nervous about me "taking over the lens" and has told me she may lock the case!
Attached Thumbnails
Click for full-size image (20180126084529693.jpg)
42.8 KB6 views

Last edited by OICURMT; 17-08-2019 at 12:05 AM.
Reply With Quote
  #9  
Old 17-08-2019, 04:57 AM
bojan's Avatar
bojan
amateur

bojan is offline
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,885
All you really need is a friend with machine shop.. and a courage... to modify the lens (because procedure is potentially irreversible).
Reply With Quote
  #10  
Old 17-08-2019, 07:28 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 18,138
I thought I scored big time when making a "deal" by relocating the clothes line in my backyard and using "left over" quickset concrete to erect a pier but getting your wife lenses for wildlife that you can use for astro later, man... that's next level! Respect.
Reply With Quote
  #11  
Old 17-08-2019, 07:52 AM
gbeal
Registered User

gbeal is offline
 
Join Date: Oct 2004
Location: New Zealand
Posts: 4,299
The saying goes, "picture is worth a thousand words".
Gary
Attached Thumbnails
Click for full-size image (A-T_Bayonet-Inside.jpg)
172.9 KB6 views
Click for full-size image (A-T_Bayonet.jpg)
194.3 KB7 views
Click for full-size image (A-T_Side_Rule.jpg)
152.3 KB7 views
Click for full-size image (A-T_T-Thread.jpg)
150.4 KB8 views
Reply With Quote
  #12  
Old 17-08-2019, 08:29 AM
OICURMT's Avatar
OICURMT
Oh, I See You Are Empty!

OICURMT is offline
 
Join Date: Apr 2010
Location: Laramie, WY - United States of America
Posts: 1,438
Quote:
Originally Posted by bojan View Post
All you really need is a friend with machine shop.. and a courage... to modify the lens (because procedure is potentially irreversible).
Well, I have access to a complete lathe setup, problem is that I haven't lathed since I was in High School and even then I was bad at it.

Guess I could ask at the University...


Quote:
Originally Posted by multiweb View Post
that's next level! Respect.
Missus has suggested she'll take me to the next level if I hoard her kit...

Quote:
Originally Posted by gbeal View Post
The saying goes, "picture is worth a thousand words".
Gary
Wow... that's the ticket. Going to try to replicate it... if not... "How much is shipping to the USA?"

Last edited by OICURMT; 17-08-2019 at 08:52 AM.
Reply With Quote
  #13  
Old 17-08-2019, 12:36 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 18,138
Quote:
Originally Posted by OICURMT View Post

Missus has suggested she'll take me to the next level if I hoard her kit.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 02:22 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
NexDome Observatories
Advertisement
Bintel
Advertisement
OzScopes Authorised Dealer
Advertisement
Lunatico Astronomical
Advertisement
Celestron Australia
Advertisement
Meade Australia
Advertisement
SkyWatcher Australia
Advertisement
Astronomy and Electronics Centre
Advertisement