Search found 157 matches

by JKT
Fri Sep 18, 2020 4:51 am
Forum: Equipment Discussions
Topic: Schneider macro varon 85/4.5 CAS @1x &2x
Replies: 20
Views: 2345

Re: Schneider macro varon 85/4.5 CAS @1x &2x

I wasn't too impressed by the tripod mount, though. 8)
by JKT
Fri Sep 18, 2020 4:41 am
Forum: Equipment Exchange
Topic: Heads-up: M52x0.75 extension tubes
Replies: 3
Views: 87

Re: Heads-up: M52x0.75 extension tubes

Those are indeed nice - especially if you want an exact length. I wish I had noticed that size earlier. The price/mm in https://www.aliexpress.com/item/522387973.html is unmatched, though.
by JKT
Thu Sep 17, 2020 2:20 pm
Forum: Equipment Exchange
Topic: Heads-up: M52x0.75 extension tubes
Replies: 3
Views: 87

Heads-up: M52x0.75 extension tubes

If you are looking for M52x0.75 extension tubes for cheap, it would seem that FOTGA extension tube systems are on sale on Aliexpress. Those include camera adapter to the tube thread and another adapter from the thread to lens, but in-between there are three extension tubes. Depending on camera make ...
by JKT
Fri Sep 11, 2020 2:11 pm
Forum: Equipment Discussions
Topic: Lomo 3.7x with DCR250, DCR150 & Canon 250D
Replies: 0
Views: 184

Lomo 3.7x with DCR250, DCR150 & Canon 250D

Here are a few more performance points for those on budget. LOMO 3.7 was used as infinite objective with cheap tube lenses on full frame 26 MP camera. The small images on each line are 1:1 crops from center to corner. No sharpening was applied. The rows in the first image are for DCR-250 and DCR-150...
by JKT
Tue Sep 08, 2020 7:21 am
Forum: Equipment Discussions
Topic: Question
Replies: 14
Views: 599

Re: Question

There are reversing rings that have 72mm on one side and something smaller on the other side. Then just Step-Up from the 37mm to the other side of the reversing ring.
by JKT
Mon Sep 07, 2020 2:24 pm
Forum: Equipment Discussions
Topic: Question
Replies: 14
Views: 599

Re: Question

That's three filters. On Aliexpress there are plenty of choices to reverse down from 72 mm. The smallest was 42mm IIRC. Then step-up from 37mm to the one you chose. I'd probably use something between 49mm and 58mm to keep the hole definitely large enough. All size combination may not be available, t...
by JKT
Mon Sep 07, 2020 10:21 am
Forum: Equipment Discussions
Topic: Question
Replies: 14
Views: 599

Re: Question

With such a big difference in size it is sometimes also possible to put one or two rings in reverse position. The dimensions have to be right and the female thread has to be through thickness, so it is touch and go. You also need to be aware, that once this is utilized, the tightening is a bit trick...
by JKT
Wed Sep 02, 2020 9:45 pm
Forum: Equipment Discussions
Topic: Thorlabs ITL200 adapters help needed
Replies: 45
Views: 1083

Re: Thorlabs ITL200 adapters help needed

I don't think they do. The RAF adapter EF->SM2 has the same length as going from EF->M42->SM2 with Thorlabs SM2A25. There is also RAF adapter that goes from EF to both M49x0.75 and M58x0.75. The length for M49x0.75 is the same as EF->M42. Corresponding Thorlabs adapter is SM2A26, which has the same ...
by JKT
Tue Sep 01, 2020 11:18 pm
Forum: Equipment Discussions
Topic: Thorlabs ITL200 adapters help needed
Replies: 45
Views: 1083

Re: Thorlabs ITL200 adapters help needed

No problems with shipping to Finland. Netherlands might well be same ... or not. Difficult to say.
by JKT
Tue Sep 01, 2020 2:53 pm
Forum: Equipment Discussions
Topic: Thorlabs ITL200 adapters help needed
Replies: 45
Views: 1083

Re: Thorlabs ITL200 adapters help needed

I think there are two issues here. First is that the ring collars have to match the tubes pretty much exactly. So you need to get them from the same source as the tube. There likely are other sources, but I ended up with Thorlabs as well. The other problems is the ITL200 and its fixing. With most le...
by JKT
Thu Aug 27, 2020 9:11 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Questions for the experts.
Replies: 12
Views: 519

Re: Questions for the experts.

In this case Raynox DCR-150 might not be such a bad idea - then again it rarely is. 8)

The downside is getting the required adapters.
by JKT
Thu Aug 27, 2020 3:02 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Questions for the experts.
Replies: 12
Views: 519

Re: Questions for the experts.

Even when currant lens is fully extended ,I'm getting vignetting in the corners, so finding infinity is out of the question as I understand that is just before the 200 mm is reached. There seems to be something odd in the above statement. Finding infinity focus is separate issue from choosing the f...
by JKT
Thu Aug 27, 2020 2:51 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Nikon 10x halos.
Replies: 8
Views: 301

Re: Nikon 10x halos.

The vignetting should not be related to halos and it could be either due to the microscope objective, your tube lens [objective] or the distance between the two ... though technically it would then be due to the latter. A picture would make estimation easier.
by JKT
Sun Aug 23, 2020 2:19 am
Forum: Equipment Discussions
Topic: Willfull misuse of some finite objectives
Replies: 2
Views: 277

Re: Willfull misuse of some finite objectives

I am not too happy about the corners either. It is hard to say whether that is due to the Mitutoyo or the tube lenses. After all, the long ones are almost 60 years old and I have only those and the two Raynoxes. Canon 250D doesn't really count.

Camera shake shouldn't be an issue with flash.
by JKT
Sun Aug 23, 2020 12:45 am
Forum: Equipment Discussions
Topic: Willfull misuse of some finite objectives
Replies: 2
Views: 277

Willfull misuse of some finite objectives

I had some spare time, so I did some testing. Namely I tested four finite objectives with infinite setup with four different tube lenses. The used tube lenses were all Schneider-Kreuznachs: Componon-S 135/5.6, Componon 150/5.6, Componon 180/5.6 and Componon 210/5.6. The first was metal construction ...