Search found 2648 matches
- Mon Feb 26, 2024 1:49 pm
- Forum: Equipment Discussions
- Topic: Componon 28mm f/4 /w RF 100mm
- Replies: 5
- Views: 350
Re: Componon 28mm f/4 /w RF 100mm
I am new to this forum and would love to explore Componon 28mm f/4 after seeing RobertOToole's website. Would it be a possible to stack with RF 100mm macro lens? I understand I will need a coupling ring. Would I need anything else? My current setup is EOS R with RF 100mm f/2.8L and Laowa 25mm 2.5-5...
- Mon Feb 19, 2024 10:19 am
- Forum: Equipment Discussions
- Topic: Resolving power / NA / diffraction limit / sensor resolution
- Replies: 4
- Views: 336
Re: Resolving power / NA / diffraction limit / sensor resolution
I've been searching for links on this topic for an article on my website, and this is a very good source:
How to decide outresolving?
viewtopic.php?p=236522
Take a look, lots of good material!
How to decide outresolving?
viewtopic.php?p=236522
Take a look, lots of good material!
- Mon Feb 19, 2024 9:44 am
- Forum: Equipment Discussions
- Topic: Resolving power / NA / diffraction limit / sensor resolution
- Replies: 4
- Views: 336
Re: Resolving power / NA / diffraction limit / sensor resolution
How does one calculate what the effective resolution of a lens is (in megapixels)? In other words: when does it no longer make sense to add more pixels? How does the resolving power (in micrometers) correlate to the sensor resolution that can resolve that power? For example, the Mitutoyo HR 10x NA ...
- Mon Feb 19, 2024 9:36 am
- Forum: Equipment Discussions
- Topic: Anybody willing to test Mitutoyo 5x and 10x
- Replies: 5
- Views: 414
Re: Anybody willing to test Mitutoyo 5x and 10x
Thanks for the offer but I think I'll wait for another copy, which will be a little bit of a gamble to get good IQ, I'll post a request at some point.Scarodactyl wrote: ↑Sun Feb 18, 2024 10:34 pmI have a spare motic, but it's not quite as good as my last motic or my mitutoyo 10x with a touch of visible axial ca.
- Sun Feb 18, 2024 10:25 pm
- Forum: Equipment Discussions
- Topic: Anybody willing to test Mitutoyo 5x and 10x
- Replies: 5
- Views: 414
Re: Anybody willing to test Mitutoyo 5x and 10x
I'm really glad Robert offered to help! I test objectives fairly often for forum members, but will be traveling soon, and would find it ticklish to get someone else's objectives tested and out the door in time. Your objectives will be in excellent hands with Robert. :D --Chris S. I'm glad to help. ...
- Sun Feb 18, 2024 6:31 pm
- Forum: Equipment Discussions
- Topic: Anybody willing to test Mitutoyo 5x and 10x
- Replies: 5
- Views: 414
Re: Anybody willing to test Mitutoyo 5x and 10x
Some US seller got his hands on few objectives (2x, 5x, 10x, 20x 80x) and I bought 2 of them - the 5x and 10x... According him they are in great condition, but I saw some posts in this forum of underperforms... I would like to test them and if necessary - use the 14 days return window. Unfortunatel...
- Fri Feb 16, 2024 1:23 pm
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
Of-course good general sharpness of a lens benefit when using HR pixelshift mode. But do realise that the most benefit of using HR pixelshift mode, is a matter of "getting away" by the negative impact from interpolation algorithm for de-mosaicking the RGB Bayer pattern. Getting a much more “clean” ...
- Fri Feb 16, 2024 9:33 am
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
Pretty sure all Canon and Nikon AF systems stop down a bit to f/8 or so to AF and don't focus wide open. I tested just now, shining a flashlight down the barrel to watch the innards of Canon EF Macro 100mm f/2.8 L IS USM mounted on Canon R7 body with EF-EOS R adapter, manual mode set on f/11. It au...
- Fri Feb 16, 2024 12:17 am
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
Adding to Chris's excellent information... Lenses at 1:1 often have some uncorrected spherical aberration that causes focus to shift when the lens is stopped down. If you focus with aperture open, this can affect manual focusing as well as automatic. --Rik Just a note or two, Nikon's AF-fine tune a...
- Thu Feb 15, 2024 5:23 pm
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
Hello Robert, Wauw, you wrote very comprehensive and detailed answers. I do appreciate very much. Thank you. - Glad I could help. One common mistake people make, and I find the fact to be to my advantage quite often is they write off older lenses due to a spec like the designed resolution being too...
- Wed Feb 14, 2024 11:47 am
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
Just checked 1:2 is in the optimized "range" of the 4/105 APO-Rodagon but in my experience since its designed for 1:6, the results aren't going to be pretty at all.
The APO-Rodagon D 120 which I am told is a re-labled Rodenstock APO Macro Sironar, should be much better at 1:2.
Robert
The APO-Rodagon D 120 which I am told is a re-labled Rodenstock APO Macro Sironar, should be much better at 1:2.
Robert
- Wed Feb 14, 2024 11:40 am
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
Hallo Robert, I have read your tests as for Laowa 100mm and Sigma 105mm Art with great interest. As all of your tests. By the clear and precise test procedures. (Like using a chip Wafer to have a full flat high detailed subject). Thank you. I appreciate that, I am always glad to hear feedback, posi...
- Wed Feb 14, 2024 10:54 am
- Forum: Macro and Micro Technique and Technical Discussions
- Topic: Reversed lenses--usefulness of electrical contacts to control aperture?
- Replies: 11
- Views: 626
Reversed lenses--usefulness of electrical contacts to control aperture?
When experimenting with reverse lens macro (on bellows) can something be gained by getting electrical contact with the reversed lens to control aperture? I'm using Canon EF 50/1.8 and 50/1.4 on a R6 to start with. Ideas and materials for a solution is there but is it worth the effort? In theory yes...
- Tue Feb 13, 2024 9:02 pm
- Forum: Equipment Discussions
- Topic: Sharpest aperture for a given macro lens
- Replies: 35
- Views: 1490
Re: Sharpest aperture for a given macro lens
It really depends on the lens, there is no "golden rule" when it comes to special applications. Some macro lenses are great at 1x, others only mediocre or perhaps even bad - regardless of the aperture. Others start off really bad but get better once stopped down. A few precious (and expensive) ones...
- Mon Feb 12, 2024 11:04 am
- Forum: Equipment Discussions
- Topic: Bellows for Fuji GFXs ii
- Replies: 78
- Views: 14769
Re: Bellows for Fuji GFXs ii
(...)I did notice they finally went to a lead-screw focus rack (CASTEL-M) at least, after decades of rack and pinion drive(...) . by Robert Sorry for the technical ignorance but why is one system better than the other? Thanks. Hi Cunha, Rack in pinion drive is only safe horizontally. Any tilt verti...