Working DIY adapter

Dmitriy Uchakin · December 24th, 2005, 08:32 PM

Ben, thank you for clarifying. I myself have 50/2.0 lense and am torn between using the optosigma+condenser or Nikon D screen. The latter is ofcourse a cheaper solution as it already includes the condenser. Ben, do you think Nikon D is better in terms of performance per dollar in my case?

Ben Winter · December 24th, 2005, 09:44 PM

I think so, although there was someone else (can't remember who) who said they couldn't stand the grain on the Nikon D. To me, it's virtually grainless, which makes sense since that's how it was designed, as a focusing screen for astrophotography. Go figure.

Dmitriy Uchakin · December 25th, 2005, 02:15 AM

Thanks Ben.

Optosigma:5 ------Nikon:6

Its funny how each night you leave this forum convinced that you figured this whole apparatus and have an exact list of parts.
But then.....
.....you wake up and read that someone has tested your design and concluded that it was junk. Back to the drawing board. And its like that every night...Brutal.

Jimmy Herdberg · December 25th, 2005, 02:23 PM

Ok, I have done some more test now and its getting better! I have a new f-mount which is perfect and I moved the planoconvex lens from the gg about 16mm and it gaved me a more straight picture and I have to zoom in less than before.

New Parts:
Nikon BR-3 Adapterring
Thorlabs Coupler ring SM2T2

I tried with two planoconvex lenses but I don't like to have any extra lenses between the lens and the gg because it change the focallength of the 35mm lens.

> I noticed that you used a condenser with an FL of 70mm.

I haven't tried any other FL of the lens but I think a short FL requires less length of the adapter. That gives less loss of light and a smaller adapter. I don't have any abberation problems with it.

I will try to post some pictures on thursday!

DJ Lewis · December 29th, 2005, 02:38 PM

With the Nikon BR-3, how much did it off set your the distance of your gg?

Jimmy Herdberg · December 30th, 2005, 10:36 AM

The nikon BR-3 adapter adds 16mm and then I have a coupler ring between the adapter and the tube which adds between 5-15mm. I can adjust the coupler ring to easier set the right distance between the groundglass and the lens. It's a lot easier to adjust the distance now instead of moving the groundglass. I used the extra space to move the planoconvex lens 16mm from the groundglass which gave me a much better image. I also got my Century Optics +7 diopter today and I'm going to do some new tests after newyear, posting new images then!

Marco Polimeni · January 10th, 2006, 07:28 PM

Jimmy, I got the Nikon BR-3 on eBay for just 10 Euro (plus 6 euros S/H from France).
I've a problem with the Thorlab tube + the 2 rings (50 USD) because the shipping cost from US to Italy, where I am, is more then 67 USD.
Please, where do you get them.

Rene Hinojosa · January 10th, 2006, 08:27 PM

What is the exact item number for the Nikon D diffusion screen, I keep getting all sorts of results on Ebay, like type E and other selections; would an F3 of F6 be recommended as the ground glass? i'm a little confused.....

Dmitriy Uchakin · January 10th, 2006, 08:45 PM

Rene,
The one that you are looking for is F3 Type D Focusing screen. Thats the one without markers. I was not able to find any online for under 50 bucks though. I did see F6 one and they are supposedly better in terms of brightness but they are also a little larger so I dont think they will fit into a thorlabs tube. If you are not using the thorlabs, F6 screen should be a good choice but I think their marking types are different so the Type D for F6 is NOT clear. I think Type B is clear for F6's but I am not 100% sure. Here are some links.

http://www.mir.com.my/rb/photography...3ver2/screens/
http://www.mir.com.my/rb/photography...eens/index.htm
http://www.astropix.com/HTML/I_ASTRO...0301/I0301.HTM

Rene Hinojosa · January 10th, 2006, 08:53 PM

Thanks, Dmitriy! I am using a 55mm ring and spacers so I think I will be using the bigger screen. Thanks again!

Marco Polimeni · January 11th, 2006, 04:41 AM

Nikon focusing screens Type-D are projected for astronomic photography so they are very bright , the grain is very fine and has no telemeter inside (because in astronomy the subject is allways on infinite and nothing must hide it).
I never tested a D screen but, from a Nikon F manual, I know that using lenses shorter then 135mm the edges of the frame starts to became darker and darker so more the lenses are shorter.
I don't know if this happens only when you use the D screen inside a Nikon viewfinder or also when you use it naked, where you have the choice to increase the distance between the screen and your eye (or your camcorder).
About this I'd like to know more from somebody who has a direct experience.

Jimmy Herdberg · January 11th, 2006, 11:16 AM

You can order it from europe germany or sweden, it should be a better choice, you have the address here: http://thorlabs.com/Distributors.cfm?PageRef=7

Marco Polimeni · January 11th, 2006, 11:25 AM

Thanks Jimmy, I've done it this morning.

What about your test ?

Jimmy Herdberg · January 11th, 2006, 04:24 PM

I will try as fast I can, it's getting dark up here really fast these days so I have to do it on daytime. Maybe tomorrow!

Jimmy Herdberg · January 25th, 2006, 05:49 PM

Now I have complete my 35mm adapter, check the latest clip at www.kokokaka.com/35mm. The shoot is at night just with a 60w lamp (the version 3 clip)! It cost me about $250 and you can screw all the parts together without any tools or glue. If you seen a better result than this please tell me! If you like this I will put up a tutorial on how to build one.

December 24th, 2005, 09:44 PM	#32
Ben Winter Trustee Join Date: Jun 2005 Location: Hollywood, CA Posts: 1,675 Images: 1	I think so, although there was someone else (can't remember who) who said they couldn't stand the grain on the Nikon D. To me, it's virtually grainless, which makes sense since that's how it was designed, as a focusing screen for astrophotography. Go figure. __________________ BenWinter.com

December 24th, 2005, 08:32 PM	#31
Dmitriy Uchakin Regular Crew Join Date: Dec 2005 Posts: 48	Ben, thank you for clarifying. I myself have 50/2.0 lense and am torn between using the optosigma+condenser or Nikon D screen. The latter is ofcourse a cheaper solution as it already includes the condenser. Ben, do you think Nikon D is better in terms of performance per dollar in my case?

December 25th, 2005, 02:15 AM	#33
Dmitriy Uchakin Regular Crew Join Date: Dec 2005 Posts: 48	Thanks Ben. Optosigma:5 ------Nikon:6 Its funny how each night you leave this forum convinced that you figured this whole apparatus and have an exact list of parts. But then..... .....you wake up and read that someone has tested your design and concluded that it was junk. Back to the drawing board. And its like that every night...Brutal.

December 25th, 2005, 02:23 PM	#34
Jimmy Herdberg New Boot Join Date: Oct 2005 Posts: 22	Ok, I have done some more test now and its getting better! I have a new f-mount which is perfect and I moved the planoconvex lens from the gg about 16mm and it gaved me a more straight picture and I have to zoom in less than before. New Parts: Nikon BR-3 Adapterring Thorlabs Coupler ring SM2T2 I tried with two planoconvex lenses but I don't like to have any extra lenses between the lens and the gg because it change the focallength of the 35mm lens. > I noticed that you used a condenser with an FL of 70mm. I haven't tried any other FL of the lens but I think a short FL requires less length of the adapter. That gives less loss of light and a smaller adapter. I don't have any abberation problems with it. I will try to post some pictures on thursday!

December 29th, 2005, 02:38 PM	#35
DJ Lewis Regular Crew Join Date: Dec 2005 Posts: 97	With the Nikon BR-3, how much did it off set your the distance of your gg?

December 30th, 2005, 10:36 AM	#36
Jimmy Herdberg New Boot Join Date: Oct 2005 Posts: 22	The nikon BR-3 adapter adds 16mm and then I have a coupler ring between the adapter and the tube which adds between 5-15mm. I can adjust the coupler ring to easier set the right distance between the groundglass and the lens. It's a lot easier to adjust the distance now instead of moving the groundglass. I used the extra space to move the planoconvex lens 16mm from the groundglass which gave me a much better image. I also got my Century Optics +7 diopter today and I'm going to do some new tests after newyear, posting new images then!

January 10th, 2006, 07:28 PM	#37
Marco Polimeni New Boot Join Date: Nov 2005 Posts: 21	Jimmy, I got the Nikon BR-3 on eBay for just 10 Euro (plus 6 euros S/H from France). I've a problem with the Thorlab tube + the 2 rings (50 USD) because the shipping cost from US to Italy, where I am, is more then 67 USD. Please, where do you get them.

January 10th, 2006, 08:27 PM	#38
Rene Hinojosa Regular Crew Join Date: May 2005 Posts: 37	What is the exact item number for the Nikon D diffusion screen, I keep getting all sorts of results on Ebay, like type E and other selections; would an F3 of F6 be recommended as the ground glass? i'm a little confused.....

January 10th, 2006, 08:45 PM	#39
Dmitriy Uchakin Regular Crew Join Date: Dec 2005 Posts: 48	Rene, The one that you are looking for is F3 Type D Focusing screen. Thats the one without markers. I was not able to find any online for under 50 bucks though. I did see F6 one and they are supposedly better in terms of brightness but they are also a little larger so I dont think they will fit into a thorlabs tube. If you are not using the thorlabs, F6 screen should be a good choice but I think their marking types are different so the Type D for F6 is NOT clear. I think Type B is clear for F6's but I am not 100% sure. Here are some links. http://www.mir.com.my/rb/photography...3ver2/screens/ http://www.mir.com.my/rb/photography...eens/index.htm http://www.astropix.com/HTML/I_ASTRO...0301/I0301.HTM

January 10th, 2006, 08:53 PM	#40
Rene Hinojosa Regular Crew Join Date: May 2005 Posts: 37	Thanks, Dmitriy! I am using a 55mm ring and spacers so I think I will be using the bigger screen. Thanks again!

January 11th, 2006, 04:41 AM	#41
Marco Polimeni New Boot Join Date: Nov 2005 Posts: 21	Nikon focusing screens Type-D are projected for astronomic photography so they are very bright , the grain is very fine and has no telemeter inside (because in astronomy the subject is allways on infinite and nothing must hide it). I never tested a D screen but, from a Nikon F manual, I know that using lenses shorter then 135mm the edges of the frame starts to became darker and darker so more the lenses are shorter. I don't know if this happens only when you use the D screen inside a Nikon viewfinder or also when you use it naked, where you have the choice to increase the distance between the screen and your eye (or your camcorder). About this I'd like to know more from somebody who has a direct experience.

January 11th, 2006, 11:16 AM	#42
Jimmy Herdberg New Boot Join Date: Oct 2005 Posts: 22	You can order it from europe germany or sweden, it should be a better choice, you have the address here: http://thorlabs.com/Distributors.cfm?PageRef=7

January 11th, 2006, 11:25 AM	#43
Marco Polimeni New Boot Join Date: Nov 2005 Posts: 21	Thanks Jimmy, I've done it this morning. What about your test ?

January 11th, 2006, 04:24 PM	#44
Jimmy Herdberg New Boot Join Date: Oct 2005 Posts: 22	I will try as fast I can, it's getting dark up here really fast these days so I have to do it on daytime. Maybe tomorrow!

January 25th, 2006, 05:49 PM	#45
Jimmy Herdberg New Boot Join Date: Oct 2005 Posts: 22	Now I have complete my 35mm adapter, check the latest clip at www.kokokaka.com/35mm. The shoot is at night just with a 60w lamp (the version 3 clip)! It cost me about $250 and you can screw all the parts together without any tools or glue. If you seen a better result than this please tell me! If you like this I will put up a tutorial on how to build one.